Sanaz Ghaffar Moghaddam; Hossein Sabouri; Abdollatif Gholizadeh; Hossein Ali Fallahi
Abstract
Introduction Hordeum vulgare L. is one of the earliest products used by humans. Estimates of cereal consumption in the 2017-2018 crop season also increased and grew by 1.4% compared to the 2017-2016 season (FAO., 2017). The compared to other crops, barley has a distinct ecological adaptation and can ...
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Introduction Hordeum vulgare L. is one of the earliest products used by humans. Estimates of cereal consumption in the 2017-2018 crop season also increased and grew by 1.4% compared to the 2017-2016 season (FAO., 2017). The compared to other crops, barley has a distinct ecological adaptation and can be cultivated in a variety of climatic conditions (Samarah, 2005). Drought stress increases when the degree of evaporation of leaves exceeds the capacity and the ability of the roots to absorb water from the soil (Naghavi et al., 2016). Plants use different mechanisms for drought resistance, including these methods of escape or drought. Dam farming is dependent on the heavens and Iran is located on the world's dryland belt. By passing from spring to summer, rainfall levels are significantly reduced, and rain, crops grow late in the growing season, reaching and filling with dry land They encounter Joe is one of the major crops grown in rain-fed areas with moderate yields. Therefore, studies are conducted to select drought tolerant cultivars or genotypes in order to increase the yield of barley due to its cultivar and the increasing global dryness (Cattivelli et al., 2008). The purpose of the present study was to provide map of continuity of SSR, iPBS and ISSR markers, drought tolerance evaluation in the studied genotypes, identification of traits related to drought tolerance and location, and determination of continuous molecular markers for QTLs controlling barley agro-morphological traits under drought stress in The vegetative and reproductive stage in the F3 population was the result of a cross between Badia × Kumino cultivars. Materials and methods In order to locate the controlling genes associated with agromorphological traits in barley grower under normal conditions and drought stress, 100 F3 families from the cross between two cultivars Badia × Comino were evaluated in a completely randomized design with three replications. This research was carried out in the greenhouse of the University of Gonbad-e-Kavos in the years 2016-2017. Among the superior attributes of parent Badia, a higher performance, stress tolerance and lower cumulative parent stress tolerance and stress tolerance were noted. The continuity map was prepared using 49 pairs of SSR microsatellite markers, 10 ISSR alleles and 90 IPBS alleles. Results In this study, the intervals between the iPBS2077-4-iPBS2074-1 and iPBS2231-1-iPBS2274-5 markers on chromosomes number 5 and 7, due to having the highest number of controlling QTLs, were observed in the reproductive and reproductive stages as the most important genomic regions have been identified and their use in breeding programs will be effective as important issues. Discussion The results of analysis of variance showed that all traits evaluated at vegetative and reproductive stage had a significant difference in probability level of 1%. Therefore, it can be noted that there is a good genetic variation among the genotypes. A comparison of the mean of traits in Badia × Kumino parents showed that for all traits evaluated in vegetative and reproductive stage, values greater than the parent had the highest trait and less than the minimum trait parent, indicating an trangressive segregation for the studied traits.
Mohammad Ali Delarampoor; Leila Fahmideh; Ziba Fooladvand
Abstract
Introduction Plant growth is severely influenced by environmental stresses such as drought, high salinity and extreme temperatures. Environmental stresses trigger a wide range of plant responses, like change in the gene expression to variability in cellular metabolism and growth. In the past years investigation ...
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Introduction Plant growth is severely influenced by environmental stresses such as drought, high salinity and extreme temperatures. Environmental stresses trigger a wide range of plant responses, like change in the gene expression to variability in cellular metabolism and growth. In the past years investigation on abiotic stresses, especially drought stress, has focused on plant resistance genes and their mechanism of function. This research revealed that a majority of the genes that have important roles in the biotic and abiotic stresses resistance encode transcription factors. Hence, the identification of genes especially regulatory ones whose expression enables plants to adapt to or to tolerate these abiotic stresses, is very essential. The NAC gene family is one of the types of genes related to transcription factors that is expressed in different tissues and growth stages. In a number of transcription factors effective in aging of the leaf has been identified. The transcription factors of this family are more associated with aging related genes and growth and development processes in response to stresses in many crops. The objective of this study was to investigate the tolerate of five wheat cultivars (Hamoon, Hirmand, Kavir, Boulani and Boulani Cross) under drought stress conditions (5, 10, 15, 20 and 25% Field Capacity) based on ratio of NAC gene relative expression and osmotic regulators modifications. Materials and methods A factorial experiment was carried out using a randomized complete block design (RCBD) with three replications during the 2017–2018 at Biotechnology Research Institute of Zabol University, Zabol, Sistan and Baluchestan Province, Iran. The experimental treatments included bread wheat cultivars (Hamoon, Hirmand, Kavir, Boulani and Boulani Cross) and drought stress levels (5, 10, 15, 20 and 25% Field capacity). The bread wheat cultivars were planted in pot. Drought stress was applied at seedling stage (four to five leaves). Physiological traits (such as Polyphenol oxidase and Proline) and the level of expression of the TaNAC67 gene were estimated in this experiment. Data analysis was performed using Ratio =2 -ΔΔCT and SAS software version 9.1. Results The results of analysis of variance (ANOVA) showed that, the effect of cultivar, drought stress and interaction of drought stress × cultivar on the relative expression of NAC gene and osmotic regulators at drought stress levels (20, 15, and 5% Field capacity) compared to normal levels (25% Field capacity) was significant. Based on the obtained results, increasing of drought stress severity increased studied traits. The results of simple effects of drought stress levels showed that increasing the levels of drought stress, the traits were increased, so that The highest TaNAC gene expression, Polyphenol oxidase and Proline of leaf was obtained in plants treated with drought stress 5% crop capacity. The results of this experiment showed that increasing the levels of drought stress with 20, 15, 10, 5% of the field capacity compared to the normal level of 25% of field capacity, among the five cultivars of bread wheat, the relative expression of NAC gene increased. In addition to increasing the relative expression of NAC gene in the seedling stage, Polyphenol Oxidase and proline accumulation increased in Hirmand cultivar and then Boulani Cross cultivar. Conclusion According to the findings of this experiment through the five Sistan region bread wheat cultivars, the Hirmand and then Boulani Cross cultivars indicated better response than other genotypes to drought stress. As a result, due to the coherence of the molecular results and studied traits, Hirmand cultivar had the best response under drought stress conditions. Performing more complementary experiments is mandatory to confirm the obtained results from Hirmand cultivar in this work.
Behnam Tahmasebpour; Soudabeh Jahanbakhsh; Ali Reza Tarinejad; Hamid Mohammadi
Abstract
]Introduction Today, wheat is grown on more land area than any other commercial crop and continues to be the most important food grain source for humans. Its production leads all crops, including rice, maize and potatoes. Wheat is the most widely grown crop in the world and provides 20% of the daily ...
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]Introduction Today, wheat is grown on more land area than any other commercial crop and continues to be the most important food grain source for humans. Its production leads all crops, including rice, maize and potatoes. Wheat is the most widely grown crop in the world and provides 20% of the daily protein and of the food calories for 4.5 billion people. It is the second most important food crop in the developing world after rice. Drought is a major environmental stress threatening wheat productivity worldwide. Global climate models predict changed precipitation patterns with frequent episodes of drought. Although drought impedes wheat performance at all growth stages, it is more critical during the flowering and grain-filling(terminal drought) and results in substantial yield losses. So drought stress is one of the most common environmental stresses that makes production limitation in wheat. According to the FAO, 90 percent of Iran is located in dry and semi-arid areas. Iran, with an average rainfall of about 250 mm, has an average of about one-third of the world's rainfall. At present, the population of Iran is about 80 million and according to forecasts, the Iranian population will pass 120 million by 2020, based on a growth rate of 2% in 1400. Therefore, increased wheat production is inevitable. Materials and methods In order to identify drought stress tolerant wheat genotypes in greenhouse and field, 30 genotypes were studied as a sub factor in split plot experiment in a completely randomized design with randomized complete block design with three replications under normal and drought stress conditions in 2016-17. Results and discussion Analysis of variance showed a significant difference between genotypes in terms of grain yield under stress and non-stress conditions. In terms of seed yield in the field, genotypes cd-1, c-93-10 and Mihan with mean of 290.535, 282.835, 311.229 g/m2 were the most tolerant and in the greenhouse, Urom and C-93-8 genotypes with an average of 5.769 and 5.236 g in 5 plants per plant were identified as the most susceptible genotype for drought stress. Also, based on the genotypic groupings based on the stress tolerance indices in field and greenhouse experiments, genotypes were located in four clusters and genotypes of cd-7, c-94-4, cd-2, c-93-5, c-93-9, cd-10, cd-11, cd-5, c- 94-6, c-94-8, cd-9, c-94-7, cd-1, c-93-3, c-93-10, and Urom were known as the most susceptible which were suitable for crosses or introductions for farmers in the target area. Considering that the use of an index is not effective for introducing the most tolerant figure and based on this principle, the results of genotypic grouping based on all indices, showed that the genotype was considered as the most tolerant genotype under greenhouse conditions due to low TOL, SSI and YP, YS, MP, GMP, HMP, STI, YI and YSI. Also, under field conditions, genotypes cd-7, c-94-4, cd-2, c-93-5, c-93-9, cd-10, cd-11, cd-5, c-94-6, c-94-8, cd-9, c-94-7, cd-1, c-93-3 and c-93-10, according to most indices, are most susceptible under field conditions. And are applicable in breeding programs for the production of high tolerance cultivars to end-of-season stress.
Samiye Aghcheli; Ali Rahemi Karizaki; Ebarhim Gholamalipour Alamdari; Abdollatif Gholizadeh; Seydeh Hakimeh Davoodi
Abstract
Introduction Cereals, have particular and important role in consume pattern in any country in the world. Study of the physiological responses of different cereal species to drought stress can be help to identify the mechanisms involved in resistance to drought. Drought stress is considered to be the ...
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Introduction Cereals, have particular and important role in consume pattern in any country in the world. Study of the physiological responses of different cereal species to drought stress can be help to identify the mechanisms involved in resistance to drought. Drought stress is considered to be the major environmental factor limiting crop growth and yield. This stress induces many biochemical, molecular, and physiological changes and responses that influence various cellular and whole plant processes that affect crop yield and quality. Some studies suggest that drought stress influences the thermal tolerance of photosynthesis. The purpose of this study was to investigate the effects of water stress on the growth, chlorophyll, Catalaz, accumulations of proline and carbohydrates of cold cereals. Material and methods Therefore, an experiment was conducted to evaluate the effect of the low irrigation on chlorophyll a, b, total, proline, soluble sugar content, catalase enzyme and grain yield as a factorial experiment based on completely randomized design with three replications in the greenhouse of College of Agriculture and Natural Resources, Gonbad Kavoos University in growing season of 2015. The first factor was different cereal species including Kohdasht bread wheat, durum wheat Seimareh, six-row barley varieties of desert, two-row barley varieties Khorram, and Line 17 of hulless barley, triticale varieties Javanilu and the second factor was different levels of low irrigation including without drought stress (control) , moderate irrigation (5 days water disruption), severe low irrigation (10 days water disruption). In this study low irrigation was applied at flowering stage. Results and discussion Results showed that there was a significant differences between low irrigation levels for chlorophyll a, b and total, proline, soluble sugars and catalase (p < 0.01). The highest chlorophyll a content in moderate irrigation and sereve low irrigation were found in durum wheat and Kuhdasht by 0.33 and 0.21 mg/g, respectively. Maximum content of chlorophyll b and total in moderate irrigation and severe low irrigation conditions was obtained from Kuhdasht wheat. According to our results, maximum and minimum content of proline in under moderate irrigation were observed in Kuhdasht wheat by 98.34, 15.83 mg/g, respectively, while under severe low irrigation, the highest and the lowest content of proline were found in Line 17 of hulless barley by 103.90 and 16.50 mg/g. In this study, the highest soluble sugar content (190.87 mg/g) was recorded in the durum wheat under severe low irrigation conditions. Conclusions According to the results of this study, different levels of drought stress caused a different response among cereal species, which can be attributed to genetic differences and their tolerance levels. As with the duration of irrigation, the amount of chlorophyll a, chlorophyll b and total chlorophyll in grain species decreased compared to the control. However, Kuhdasht cultivar was more resistant to drought stress than other species.
Hamed Derogar; Baratali Fakheri; Nafiseh Mehdinezhad; Rahmat Mohammadi
Abstract
Introduction Wheat is the most widely grown crop in the world, which has the highest crop area.. Ageilops tauschii, Aegilops speltoides, Triticum urartu, are diploids In terms of ploidy level, diploid species (2n=2x=14), from wild relatives of wheat and, respectively, has a DD genome and a genome D agent ...
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Introduction Wheat is the most widely grown crop in the world, which has the highest crop area.. Ageilops tauschii, Aegilops speltoides, Triticum urartu, are diploids In terms of ploidy level, diploid species (2n=2x=14), from wild relatives of wheat and, respectively, has a DD genome and a genome D agent in modern bread wheat, Includes BB genome and AA genome. Drought stress is an abiotic stress that is considered as one of the important factors in decreasing plant growth and crop production in most parts of the world, especially in Iran, and it leads to oxidative stress, Plants have different potent in drought stress in all aspects of development, including physiological, biochemical, morphological and anatomical, so plants use different strategies and protection systems against stress. The most important strategies are the change in antioxidant enzymes activity and increase or decrease in protein-induced proteolysis and changes in the chlorophyll and carotenoid levels. The aim of this study is to investigate the effect of different drought levels stress on some physiological traits in diploid (wild cultivars), tetraploid (durum wheat) and hexaploid (bread wheat) species. Materials and methods In order to investigate the effect of different drought stress levels on some biochemiccal characteristics, a research project was conducted in 2016-2017 in the greenhouse of Zabol Agricultural Faculty as factorial experiment in a completely randomized design with three replices. The first factor was wheat species and cultivars (Tauschii, Speltoides, Urartu, Shabrang, Behrang, Sistan, Argh) and the second factor was drought stress (90, 70, 50 and 30 percent of field capacity). The traits studied in this study were antioxidant activity (including superoxide dismutase, catalase and ascorbate peroxidase), protein, chlorophyll a, chlorophyll b and malondialdehyde activity. Data analysis was performed using SAS software version 9/9, the mean of data was analyzed by Tukey’s test (p≤0.01) and graph charts were drawn by Excel software. Results and discussion The results showed that drought stress had significant effect on the concentrations of protein, chlorophyll a and b, carotenoid, catalase, superoxide dismutase, ascorbate peroxidase and malondialdehyde. That's while with increasing the stress, the amount of ascorbate peroxidase varied, so that initially increased and then decreased. This represents the activation of antioxidant system in different wheat species to increase drought tolerance. With increasing drought stress up to 50 percent of field capacity, protein, chlorophyll and carotenoid amounts increased, but with the higher stress these amounts decreased. So it can be stated that to reduce the damage caused by water shortages in the higher stress, the plant has resisted to drought by increasing proteolysis and decreasing protein amount. Conclusion Due to the fact that plants tolerate some degrees of stress, the studied wheat cultivars were able to tolerate 50 percent of field capacity, and with increasing the stress subsequently to higher levels, they showed a decrease in activity and some biochemical traits. Among all the cultivars, Shabrang showed the highest values. Therefore, in this experiment as it was shown by other researches, the superiority of this cultivar has been determined. Also, the lowest amount was related to Sistan cultivar, which received the lowest values, However, during the process of applying stress, the savage wheat cultivars were superior for these traits. Therefore, further studies are necessary on the wild wheat varieties. Acknowledgements We are thankful to Dr. Kamal ghasemibezdi and members of the Faculty of Agriculture Research Laboratory.
Soghra Emami; Ali Asghari; Hamidreza Mohammaddoust Chamanabad; Ali Rasoulzadeh; Elnaz Ramzi
Abstract
Introduction Wheat is one of the most important and strategic products and is the most valuable food for the people of the world, especially the Third World countries. Wheat farms in arid and semiarid regions in rainfed conditions are generally exposed to drought stress at the germination, emergence ...
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Introduction Wheat is one of the most important and strategic products and is the most valuable food for the people of the world, especially the Third World countries. Wheat farms in arid and semiarid regions in rainfed conditions are generally exposed to drought stress at the germination, emergence and the late stages of the growing season. The effects of PEG simulated osmotic stress on morphological traits, such as root and stem length, fresh and dry weight of root and stem have been studied in a large number of previous studies. This research was conducted to investigate the effect of osmotic stress on morphological characteristics of advanced durum wheat lines and to classify the studied lines in terms of osmotic stress tolerance and to identify the susceptible and tolerant lines. Materials and methods In order to study the effect of osmotic stress in durum wheat lines, 83 lines were evaluated at two levels including zero (control) and -4 bar osmotic potential. The experiment was done in tow condition based on completely randomized design with four replications. Polyethylene glycol 6000 was used to create -4 bar osmotic potential. The lines were cultivated in plastic pots with 10 cm diameter and 50 cm height that filled with sand. Irrigation of all pots until germination of seeds was done by normal water. After germination stage, control pots irrigated with Hogland solution and under stress pots irrigated with Hogland solution contain PEG6000. The Measurement of morphological traits included root and shoot length, fresh and dry weight of root and shoot, root volume and root area was done one month after applying stress and Ti and SIIG indices were calculated based on these traits. After calculating the Ti index for the studied lines and obtaining the highest and lowest tolerance index for each trait, they were used to calculate the distance of each line from the positive ideal genotype (d +) and the ideal negative genotype (-d). In addition to using the SIIG index in this analysis, the grouping of the studied lines was done using cluster analysis using Ward method. This grouping was performed by applying the average of the lines for Ti index and the results of cluster analysis were compared with the results of the SIIG index. Statistical analysis of data was done using SPSS16 software and comparison of averages was done with Duncan's test at a probability level of 1%. Results and discussion The results of variance analysis of Ti showed that the lines had a significant difference in all traits at 1% probability level. Based on the results of the comparison of the average of durum wheat lines in terms of the Ti indices calculated from the traits, in most traits, the lines 9, 26, 34, 40 and 53 the lines had the highest value of Ti index and the lines 22, 29, 51, 77 and 79 were the lines with the lowest value of Ti index. The high level of this index on each line indicates the high tolerance of these lines to osmotic stress. The results of line rating using SIIG method showed that lines 9, 16, 24, 25, 26, 34, 35, 38, 53 and 64 had the highest SIIG in comparison with other lines and these lines were identified as the most tolerated ones to osmotic stress. Lines 22, 29, 30, 51, 52, 61, 73, 77, 79 and 82 were ten lines with the least amount of SIIG and were the most sensitive lines to osmotic stress. Conclusion Based on the indices of Ti, lines 34, 9, 53, 26, 40, 16, 64, 7 have a high average and lines 29, 77, 22, 30, 51, 13, 79 have the low average of the traits . According to the SIIG index, the lines 34.9, 53, 26, 16, 64, 38, 25, 35, 24 were in the high average group and the lines 61, 52, 51, 30, 82, 73, 79, 77, 29, 22 were in the low average group. These results were also obtained in cluster analysis, and the results of this grouping were highly consistent with the results of the lines' ranking using the SIIG index. This shows that the SIIG index helps the researcher to sum up the results of different indices. In general, it can be presented that in this study, the lines 9, 34, 53, 26, 16, 64, 38, 25, 35, 24 were tolerant lines and the lines 61, 52, 51, 30, 82, 73, 79, 77, 29, 22 were susceptible ones to osmotic stress.
Roghayeh Fatemi; Mehrdad Yarnia; Soleiman Mohammadi; Ebrahim Khalil Vand; Bahram Mirashkari
Abstract
Introduction Barley (Hordeum vulgare L.) is a widely cultivated cereal crop in many rainfed areas in the Mediterranean region where drought is considered the main yield-limiting factor. In such marginal lands, yield losses is associated with drought conditions resulted from low and inconsistent precipitation ...
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Introduction Barley (Hordeum vulgare L.) is a widely cultivated cereal crop in many rainfed areas in the Mediterranean region where drought is considered the main yield-limiting factor. In such marginal lands, yield losses is associated with drought conditions resulted from low and inconsistent precipitation during the whole plant growth cycle, either early in the fall or winter (initial drough conditions) or late during spring (terminal drought).Drought stress reduces grain yield of barley through negative affecting the yield components i.e. number of plants per unit area, number of spikes and grains per plant or unit area and single grain weight, which are determined at different stages of plant development. Materials and methods In order to Consistency Study, Grain Yield Potential and Relationship between Traits in Spring Barley Cultivars and Lines, an experiment was done in Agricultural and Natural Resources Research Station of Miandoab in cropping 2016-2017. In this research, 12 lines and variety were evaluated in a randomized complete block design with three replications under complete irrigation and cut irrigation after 50% flowering (Grain filling water stress). In present study Plant Height, spike length, Peduncle length, Spike weight, spike number / m2, Grain number / spike, 1000 grain weight, Biomass, Grain yield and harvest index were measured. Analysis of variance was performed using the SAS9.4 and SPSS programs. Result Results of analysis of variance showed that there was a significant difference between genotypes for all traits, Also, Also, the interaction of genotype in conditions was significant on all traits except spike length and 1000-grain weight. results showed that water deficit redused plant height, peduncle length, grain number per spike, 1000 seed weight, biomass, grain yield and harvest index by 8.39, 2.10, 7.03, 46.63, 37.18, 42.79 and 5.71 percent respectively. Among the studied genotypes, jonoob cultivar, M-88-2 and MD-88-15 by 4.42, 4.43 and 4.93 t/ha under normal condition and 3.44, 3.75 and 3.66 t/ha respectively under water deficit condition produced the highest grain yield compared to other genotypes. In both conditions correlation of grain yield with spike weight, number of grain per spike, biological yield and harvest index was positive and significant. Based on stepwise regression analysis, under normal conditions, number of seeds per spike, spike weight and number of spikes per square meter (with, R2 = 0.76), and under water deficit condition grain number, plant height and 1000 grain weight (with, R2 = 0.62), justified in grain yield variation. Based on the results of path analysis in normal conditions, seeds per spike, spike weight and number of spikes per square meter and in water deficit condition grain number, plant height and 1000 grain weight had a direct positive and significant effect on grain yield. In percent study seed number per spike was identified as the most effective trait for grain yield in both conditions. Cluster analysis classified the cultivars and barley lines under normal condition in two groups and in under water deficit, into three groups, which under normal condition cluster 2 (in cluding lines of Jonoob, M-88-2 and MD-88-15) and in water deficit condition cluster 1 (Jonoob, M-86-5, M-88-2, RIHANE 03 and MD-88-15) were obtained The highest grain yield and yield components. Conclusion According to the results of this study, there were a high genetic variation between barley Cultivars lines both normal and water deficit condition. Also genotypes of Jonoob, M-88-2 and MD-88-15 by achieved the highest grain yield in both conditions were identified as the most suitable genotypes for cultivation in the West Azarbaijan region. Also, grain number per spike in both conditions was recognized as the most effective trait on grain yield.
Ali Azarinasrabad; Seyed Mohsen Mousavinik; Mohammad Galavi; Masoud Khazaei; Seyed Alireza Beheshti; Ali Reza Sirousmehr
Abstract
Introduction The yield of each crop is determined by several factors, which affect the growth and development of the plant. These factors include environmental, managerial, and plant factors. Environmental stresses are one of the most important environmental factors, including the most important stresses ...
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Introduction The yield of each crop is determined by several factors, which affect the growth and development of the plant. These factors include environmental, managerial, and plant factors. Environmental stresses are one of the most important environmental factors, including the most important stresses of drought stress. The aim of this study was to investigate the effects of drought in the vegetative and reproductive growth stages on Yield, its Components and Biochemical traits in grain Sorghum genotypes. Materials and Methods In order to evaluate the effect of water stress on grain yield and its components and Biochemical traits in grain Sorghum genotypes (Sorghum bicolor L.), a field experiment as a split plot design was carried out with 3 replications in 2014 at the research farm of the southern khorassan Agriculture and natural resources research and education center. Water stress treatments including normal irrigation (control), irrigation cut off in vegetative growth stage(emergence of terminal leaf as rolled) and irrigation cut off in generative growth stage(50% of plants in start of flowering) as the main plot and 10 genotypes of sorghum including KGS29, MGS2, Sepideh, KGF27, MGS5, KGF5, KGF17, KGF13 and KGF30 were considered as sub plots. Each plot consists of 4 lines with a length of 6 m and line spacing of 60 cm, between plants on row 10 cm was considered. In addition, between each plot and the adjacent plot a line was considered. To determine the yield components of each plot, half a meter in length was harvested and number of plants, number of panicle, grain yield, 1000 seeds weight and number of seeds per panicle were determined. To determine the yield , after the removal of 2 margin lines and a half meter of beginning and end of each plot, plants were harvested from the surface of 3 square meters. Biochemical parameters including chlorophyll a, chlorophyll b, carotenoids, proline and carbohydrates were measured on the flag leaf after flowering stage in each plot. chlorophyll a content, chlorophyll b, and carotenoid content was done according to Arnon method. Simple correlation coefficients between the characteristics studied under normal conditions and drought stress conditions were calculated using SPSS software version 13. Results and Discussion Results showed that water stress had significantly effect on grain yield, 1000 seed weight, seed number per panicle and caused to decrement of them. Genotypes were significantly different for all traits, indicating high variability among them. The interaction between water stress and genotype did not show a significant difference about 1000 seed weight, other traits which mentioned above showed a significant difference in this aspect. The results of correlations between the studied traits showed that in normal conditions (without stress), plant height, number of seeds per panicle, Brix of stem sugar, free leaf proline content, biological yield and harvest index could be used to improve seed yield. In terms of drought stress, stem sugar, plant height, canopy temperature, free leaf proline content had the highest correlation with yield and its components. Conclusions In general, physiological traits due to their low cost could be used as good indicators in water stress investigations and provide more comprehensive information as compared with morphological traits. Keywords: Free prolin, Generative growth, Irrigation cut off, Sorghum, yield
Hamed Narimani; Raouf Seyed Sharifi; Razieh Khalilzadehrazieh; Golamreza Aminzadeh
Abstract
Water limitation is one of the most important abiotic factors that can limit plant growth and yield particularly in arid and semiarid regions. In order to study the effects of supplementary irrigation and nano iron oxide on chlorophyll content and grain filling components of wheat (Triticum aestivum ...
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Water limitation is one of the most important abiotic factors that can limit plant growth and yield particularly in arid and semiarid regions. In order to study the effects of supplementary irrigation and nano iron oxide on chlorophyll content and grain filling components of wheat (Triticum aestivum L.) under rainfed, a factorial experiment was conducted based on randomized complete block design with three replications in Agricultural Research Station of Ardabil in 2016. Factors were included three levels of irrigation (no irrigation as rain fed, supplementary irrigation at heading and booting stages) and foliar application of nano iron oxide in four levels (without nano iron oxide as control, application of 0.3, 0.6 and 0.9 g L-1). Results showed that supplementary irrigation at booting stage and 0.9 g L-1 nano iron oxide increased grain yield, chlorophyll a, b, total chlorophyll and carotenoeids (16.79, 57.78, 64.32 and 115.21 % respectively) in comparison with rain fed and no application of nano iron oxide. Application of 0.9 g L-1 nano iron oxide and supplementary irrigation at booting stage increased grain filling rate, grain weight, grain filling period, effective grain filling period and grain yield (12.5, 47.36, 16.95, 29.18 and 38.43% respectively) in comparison with no application of nano iron oxide under rainfed condition. Generally, it seems that application of nano iron oxide and supplementary irrigation can be as a proper tool for increasing grain yield and grain filling period under rain fed condition
Fardaneh Osati; Touraj Mir Mahmoodi; Bahman Paseban Eslam; Saman Yazdan Seta; Hasan Monirifar
Abstract
IntroductionThe castor bean (Ricinus communis L.), is an oilseed of relevant economic and social importance. From its seeds is extracted an oil of excellent properties, having wide use as industrial input and several applications. It is cultivated since the times of the ancient civilizations, the castor ...
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IntroductionThe castor bean (Ricinus communis L.), is an oilseed of relevant economic and social importance. From its seeds is extracted an oil of excellent properties, having wide use as industrial input and several applications. It is cultivated since the times of the ancient civilizations, the castor bean is a rustic plant, resistant to drought, belonging to the family of Euphorbiaceae, The purpose of this investigation was study effect of irrigation levels and spraying of chemical fertilizers on some physiological traits and grain yield in castor. Drought stress, in addition to the negative effect on yield, causes or exacerbates other stresses, especially the stress of nutrient deficiencies for the plant. Material and MethodsThis experiment was conducted in East Azarbaijan Agricultural Research and Education Center, Tabriz- Iran at 2017 crop season. Field experiment was carried out by a split plot design based on completely randomized block design with three replications. The first factor included irrigation levels including control (normal irrigation), irrigation after 80 mm and 140 mm evaporation from the pan evaporation in the main plot and eight spraying chemical fertilizers including sulfur, potassium, nitrogen, sulfur + potassium, sulfur + nitrogen, potassium + nitrogen, sulfur + potassium + nitrogen and control as spraying in sub plots. In this study, plant height, chlorophyll index, leaf area index, leaf weight, leaf temperature, water relative content (RWC), relative growth rate (TGR), number of pods, biological yield and grain yield were measured. Also Traits were analyzed by using SAS 9.2 software and means comparison was tested by least significant difference (LSD). Result and DiscussionThe results showed that the effect of irrigation levels on all traits was significant, there was a significant difference between spraying chemical fertilizers in terms of all traits except relative growth rate, furthermore the interaction of two treatments was significant on all traits except chlorophyll index, leaf area index, leaf temperature and leaf relative water content. Mean comparison of irrigation treatments showed that irrigation after 140 mm evaporation decreased the chlorophyll index, leaf area index and leaf relative water content compared to normal irrigation (control) 77.12, 48.86 and 16.85 percent respectively and increased the leaf temperature by 17/33 percent, Also, the increase of chlorophyll index, leaf area index and leaf relative water content in S + N + K fertilizer spraying treatments were 13.48, 38.29 and 73.7%, respectively, and the leaf temperature decreased by 25.25% in comparison with control treatment (non-spraying). In this study, the highest plant height, leaf weight, relative growth, pod number, biological yield, and grain yield by average of 111.67 cm, 13.63 grams, 0.009 grams per day, 79.38 pods, 5 tons per hectare and 53.1 tons per hectare was assigned to normal irrigation and spraying chemical fertilizers of K + S + N . ConclusionAccording to the results of this study, it can be stated that, S + N + K spraying had a positive effect on the increase of yield components and grain yield. Also, this treatment was able to moderate the effects of drought stress on yield and yield components. So S + N + K fertilizer application is recommended for achieving high grain yield in castor
Usef Sohrabi; Amir Ahmadi; Gholam-reza Heidari; Adel Siosemarde
Abstract
Water deficit stress is one of the most important restrictive factors of crop yield. In arid and semi-arid regions of world, the seasonal drought is the most important restrictive factor of development cultivating and corn production. Deficit of nutrients in soil and sufficient inaccessibility to nutrients ...
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Water deficit stress is one of the most important restrictive factors of crop yield. In arid and semi-arid regions of world, the seasonal drought is the most important restrictive factor of development cultivating and corn production. Deficit of nutrients in soil and sufficient inaccessibility to nutrients is from factors that aggravate the drought effects on plant. Therefore, the present experiment was conducted in order to study of the effect of zinc and sulfur fertilizers application levels on physiological characteristics and grain yield of maize under drought stress condition.The results showed that drought stress reduced relative water content of leaf, photosynthesis and grain yield, and with increasing severity of drought stress, amounts of these traits were intensively decreased. The sulfur and zinc fertilizers application increased amount of this traits and decreased percent of cell membrane damage. However, positive effects of zinc on these traits were lesser than sulfur. Sulfur application increased maize grain yield 50% and 45% under full irrigation and severe drought stress, respectively. Results indicated that use of sulfur fertilizer failed to prevent the effect of drought stress on grain yield but largely moderated its effects and thus, sulfur and zinc fertilizers application, especially sulfur can be useful and advisable in full irrigation and deficit irrigation conditions.In order to study of the effect of zinc and sulfur fertilizers application levels on physiological characteristics and grain yield of maize under drought stress condition, an experiment was conducted in research farm of university of Kurdistan in spring of 2009. The experiment was arranged in split-plot factorial based a randomized complete block with four replications. Three irrigation levels, including full irrigation(-2 bar), moderate drought stress(-7 bar) and severe drought stress(-12 bar) was allocated to main plots. Two sulfur application levels, including non-application(control) and application of 30 kg/ha and two zinc application levels as spraying of 1 kg/ha and non-application(control) were considered as sub factors. In order to study of the effect of zinc and sulfur fertilizers application levels on physiological characteristics and grain yield of maize under drought stress condition, an experiment was conducted in research farm of university of Kurdistan in spring of 2009. The experiment was arranged in split-plot factorial based a randomized complete block with four replications. Three irrigation levels, including full irrigation (-2 bar), moderate drought stress (-7 bar) and severe drought stress (-12 bar) was allocated to main plots. Two sulphur application levels, including non-application (control) and application of 30 kg/ha and two zinc application levels as spraying of 1 kg/ha and non-application (control) were considered as sub factors. The results showed that drought stress reduced relative water content of leaf, photosynthesis and grain yield, and with increasing severity of drought stress, amounts of these traits were intensively decreased. The sulphur and zinc fertilizers application increased amount of this traits and decreased percent of cell membrane damage. However, positive effects of zinc on these traits were lesser than sulfur. Sulfur application increased maize grain yield 50% and 45% under full irrigation and severe drought stress, respectively. Results indicated that use of sulfur fertilizer failed to prevent the effect of drought stress on grain yield but largely moderated its effects and thus, sulfur and zinc fertilizers application, especially sulfur can be useful and advisable in full irrigation and deficit irrigation conditions.
Ali Shirkhani; Safar Nasrolahzadeh; Saeid Zehtab Salmasi
Abstract
Introduction The area, production and productivity of maize have increased several-fold over the last five decades. In Asia, maize has recorded the fastest annual growth (around 4%), as compared to other cereals. In 2015 with about five million tons of corn, Iran was world’s fifth largest corn ...
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Introduction The area, production and productivity of maize have increased several-fold over the last five decades. In Asia, maize has recorded the fastest annual growth (around 4%), as compared to other cereals. In 2015 with about five million tons of corn, Iran was world’s fifth largest corn importer. Maize is one of the main crops for poultry and livestock feed in Iran. Maize is the number three crop after wheat and rice in terms of area and production and number two, only after wheat in terms of productivity. The average of area in Kermanshah province in recent years has been more than 45,000 hectares. But in 2015 this amount has decreased by 30 thousand hectares, 15580 hectares, which is the main reason for water scarcity in the region. On the other hand application of chemical fertilizers in conventional agriculture severe environmental problems, increased production costs and negative effects on biological cycles causes. The objective of this study was to determine the effect of biofertilizers and chemical fertilizers on yield and yield components of Maize under normal and deficit irrigation condition in western Iran region and looking for the best biological treatments could be applied to the maize to get a high yield in addition to keep our environment clean and safe. Materials and methods Field experiments were conducted for two years (2014 – 2015) at the agricultural research farm, Agricultural and Natural Resources Research Centre in Kermanshah, Iran. In this research, effects of vermicompost and Azotobacter as a boifertilizers and chemical fertilizers on yield and yield components of Maize under normal and deficit irrigation was investigated in two sites. Sites included normal irrigation and deficient irrigation (65% optimum water requirement) and each site was conducted as the factorial split plot in a randomized complete block design with three replications and three factors. Treatments included Azotobacter in the main plots (non-inoculation and inoculation), vermicompost (consuming 0, 2, 4 and 6 ton/ha) and chemical fertilizers included N,P,K in tree levels (100% recommendation based on soil test, 50% recommendation and no fertilizer) in the sub plots. Irrigations were done at 7 day intervals. Irrigation treatments (deficit and adequate irrigation) in the middle phase of growth stage (approximately V6) began. Beginning on these dates, water was applied at weekly intervals based on the amount of evapotranspiration for the previous week as determined by the on-site weather station using a modified version of the Penman FAO equation. Statistical analysis included analysis of variance to compare mean by least significant difference (LSD) by SAS statistical software and graphs were performed by EXCEL. Results The yield of maize was significantly influenced by deficient irrigation; Results showed that during the both research years, grain yield was decreased from 8.2 ton/ha to 4.4 ton/ha by deficient irrigation. Although, application of vermicompost led to increase in grain yield, the highest grain yield was related to integrated treatments 6 ton/h vermicompost and 100% chemical fertilizers recommendation based on soil test. Results also indicated that the use of 6 ton/ha vermicompost and Azotobacter in soil, 50% of the maize fertilizer supplied. The results showed that combined use of bio-fertilizers with chemical fertilizers increased the grain yield. Therefore the uses of biological fertilizers significantly reduce the consumption of chemical fertilizers and reduce the adverse environmental effects. On the other hand from this experiment, application of vermicompost in combination with chemical fertilizers showed better performance than only chemical fertilizers, even in 100% recommendation based on soil test treatments. It can be stated that the increase in growth parameters of maize are due to greater availability of nitrogen in full organic and integrated treatments. In full chemical treatments most of nitrogen would be leached from the soil profile. In addition, high porosity and water holding capacity of vermicompost that helps in better aeration and drainage. Moreover use of 6 ton/ha vermicompost and Azotobacter in treatments with no chemical fertilizers produced 7 and 4.4 ton/ha grain yield in normal and deficit irrigation respectively.
Sanaz Rajabi Khamse; Abdolrazagh Danesh Shahraki; Mohammad Rafieiolhossaini; Keramatolah Saeidi; Mahdi Ghobadinia
Abstract
Introduction The importance of oilseeds for human and livestock in terms of providing energy, has special value among agricultural products. Due to the shortage of oilseeds cultivation in Iran, billions of dollars spend to import oilseeds and crude oil to the country, annually. Flax (Linum usitatissimum ...
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Introduction The importance of oilseeds for human and livestock in terms of providing energy, has special value among agricultural products. Due to the shortage of oilseeds cultivation in Iran, billions of dollars spend to import oilseeds and crude oil to the country, annually. Flax (Linum usitatissimum L) is used for its oil and fiber in several industries. Flaxseed obtains bioactive compounds and components including linolenic acid, lignans, omega-3, and other essential compounds. In many parts of the world, drought is the main factor which limits flax yield. Reductions in grain yield, physiological traits, oil yield and percentage were reported in many oilseeds crops under drought stress. The use of bacteria as priming, cause plants tolerance to environmental stresses. Plant growth promoting bacteria increase crops yield by regulating hormonal and nutritional levels, resistance to plant pathogens, solubilizing of elements and other mechanisms. Since water deficit is one of the main limiting factors of crops production in Iran, on the other hand, the cultivation and production of oilseeds in Iran is low, therefore, this research was carried out in order to investigating the effect of plant growth promoting bacteria on production of flax under water deficit conditions. Material and Methods This experiment was conducted in the research farm of Shahrekord University in 2013-2014 in split-plot based on randomized complete block design with three replications. The experimental factors were irrigation in three levels (100, 75 and 50 % of plant’s water requirement) and plant growth promoting bacteria in seven levels (No inoculation and inoculation by six bacteria including Bacillus sp strain1, Bacillus sp strain2, Bacillus amyloliquefaciens, Azotobacter Chroococcum, Pseudomonas putida and Azospirillium lipoferum). Before stress applying, flooding irrigation was done one day apart. Stress was applied 14 days after planting date, based on plant's water requirement. Stress was carried out base on 75 and 50% plant’s water requirement. At flowering stage, number of flower heads per plant measured. Plant height, number of capsules per plant, number of seeds per capsule and 1000 grain weight were measured at harvesting stage. After oil extraction, oil percentage was calculated. The results of variance analysis was done by using of SAS software, comparison of means by LSD and the interactions of mean comparison by using slicing method. Results and Discussion Main effects of irrigation levels and bacterial treatments on all traits were significant. Interaction effect of investigated factors on plant height, number of stem and flower heads per plant, number of capsules per plant, 1000 grain weight, biological yield, grain yield and grain oil percentage were significant while its effect on number of grain per capsules was not. The highest grain yield and grain oil percentage was obtained in 100 % of plant’s water requirement. These treatments had increasing of 88% and 28% in comparison with 50 % of plant’s water requirement, respectively. Within each three irrigation levels, the bacterial treatments had the maximum amount of measured traits compare to control treatment. The effect of Bacillus sp strain1, Bacillus amyloliquefaciens and Azotobacter Chroococcum in most of the investigated traits were more pronounced. Bacillus sp strain1 had the highest grain yield and grain oil percentage in three irrigation levels. Conclusions According to the results, , the amount of measured traits decreased by increasing drought stress levels, however, bacterial treatments reduced the effects of stress in comparision with control treatment. Among bacterial treatments, Bacillus sp strain1, Bacillus amyloliquefaciens and Azotobacter were more effective on reduction effects of stress. Also the highest grain yield, biological yield, and oil percentage were found in these bacterial treatments. Probably these microorganisms, especially Bacillus species, have increased plant production due to their phosphate solubilizing ability, IAA, cytokinin and ACC-deaminase enzyme production and better absorption of nutrients.
Majid Ghanbari; Ali Mokhtassi-Bidgoli; Parniyan Talebi-Siah Saran
Abstract
Introduction Oilseeds after grains are the second most important source of energy for human societies and the meal produced from the industrial process of oil production is also considered to be one of the important items in livestock feed, poultry and aquaculture in terms of protein richness. (Yassari ...
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Introduction Oilseeds after grains are the second most important source of energy for human societies and the meal produced from the industrial process of oil production is also considered to be one of the important items in livestock feed, poultry and aquaculture in terms of protein richness. (Yassari et al., 2014). Soybean (Glycine max) is an annual dicotyledonous, from Poaceae family and one of the most important oily seeds that is widely used in agriculture and industry (Yassari et al., 2009). Abiotic stresses affect different aspects of plant growth, such as reduction and delay in germination, decrease in development rate, decrease in plant organs growth, and decrease in plant life duration and finally decrease in dry matter production. Among abiotic stresses, drought stress is considered to be the most influential type of stress in the production of oil seeds in the world and can greatly reduce production on many arable lands. One of the primary effects of drought is the reduction of water content of plant tissues (Ghanbari et al., 2016). Soil microorganisms are effective in fixing nitrogen in air and dissolving insoluble phosphates, as well as synthesizing growth stimulating hormones such as indole acetic acid, gibberellins, cytokinins, as well as the synthesis of vitamins and amino acids, and increases yields (Viscardi et al., 2016). Considering that most of the country's lands are affected by drought stress and soybeans are susceptible to drought stress, as well as due to the use of biofertilizer as a kind of drought stress resistance strategy and its effect on soybean growth and development, this study was carried out to investigate the effect of Azotobacter chroococcum in combination with Pseudomonas putida on yield and yield components of soybean and its hormonal changes. Material and methods The present experiment was conducted to study the effect of Azotobacter nitrogen fixation bacteria in combination with Pseudomonas putida phosphate solubilizing bacteria on reducing the effects of irrigation water shortage on soybean cultivars under field conditions. This research was carried out as a factorial experiment in a randomized complete block design with three replications in Tarbiat Modares University in 2015. Factorial combinations of four irrigation regimes (15% (control), 30% (mild stress), 45% (moderate stress) and 60% (severe stress) of available soil moisture depletion) and four soybean seed inoculation groups (control or without bacteria, inoculum with Azotobacter, inoculation with Pseudomonas putida, and inoculation with both bacteria) were considered. Drip irrigation (T-tape) was applied The row length in each experimental plot was 6 m, 50 cm apart. The distance between the plots and between the repetitions was 1 and 3.5 m, respectively. Plant to plant distance within each row was 8 cm. The irrigation schedules were based on soil moisture discharge of field capacity at the root zone of soybean with a depth of about 30 cm. Results The results of this study showed that main effects of irrigation regimes and biofertilizer were significant for all traits except grain number per pod. The highest pod number per plant, grain yield, phytohormones such as indole acetic acid, gibberellins, cytokinins and ABA were obtained from combined application of Azotobacter and Pseudomonas putida. The highest pod number per plant, grain number per pod, grain yield, phytohormones such as indole acetic acid, gibberellins and cytokinins were observed in non-stressed control, while the highest ABA was found in severe drought stress. Azotobacter alone, Pseudomonas putida alone, and the combined application of both bacteria increased 25%, 30% and 42% seed yield, respectively, in comparison with control. Conclusion In general, it can be concluded that these microorganisms are able to increase yield and yield components, the phytohormones such as indole acetic acid, gibberellins and cytokinins, and plant resistant under water deficit conditions and decrease severe yield losses.
Khalil Karimzadeh- Asl; Abolfazl Baghbani Arani
Abstract
Introduction Since medicinal plants in natural areas spread within the broad geographic limitations and collection and access to them is not cost-effective and on the other hand, the use of natural habitats will not be enough for the pharmacy industry, therefore, it is necessary to grow these plants ...
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Introduction Since medicinal plants in natural areas spread within the broad geographic limitations and collection and access to them is not cost-effective and on the other hand, the use of natural habitats will not be enough for the pharmacy industry, therefore, it is necessary to grow these plants in agricultural areas. In this regard, the choice of the landraces and suitable cultivars and nutrition and irrigation management, play an important role in increasing the quantity and quality of medicinal plants and reduce the negative effects of various environmental stresses on plants. Water deficit stress, permanent or temporary, limits the growth and the distribution of natural vegetation and the performance of cultivated plants more than any other environmental factor. Water stress have altered plants ‘metabolism significantly, thereby attenuating the growth, photosynthesis, and ultimately yield of the plants. Accordingly, it is very important to identify the mechanisms through the plant adapts to various conditions and resists against stresses, and to understand possible ways to address such stresses. In addition, under such conditions, drought management is an essential necessity. Cultivating plants with lower water requirements is a solution for effective management of available water resources. Being largely adaptable to a wide spectrum of various weather conditions, cumin serve as an economically efficient product in terms of water scarcity. Furthermore, in order to effectively manage water consumption in agriculture, adoption of various farming techniques, such as application of organic fertilizers or improving biological conditions of soil may render effective for reducing the impacts of water stress, while less use of chemical fertilizers may add to agricultural sustainability and health of medicinal plant. Materials and methods In order to study the effects of water deficit stress and biofertilization on seed yield, essential oil percentage and essential oil yield of green cumin, a split plot experiment was laid out in a randomized complete block design with three replications in the Alborz research station field in 2015 and 2016. Main factor included of irrigation with 60, 110 and 160 mm evaporation from pan and sub factor consisted of four biological fertilization (control, nitroxin fertilizer, biological phosphorus and nitroxin with biological phosphorus). In this experiment total chlorophyll (chl a+b), chl a and b, relative water content, potassium, phosphorus and nitrogen content of grain, proline, essential oil percentage and essential oil yield and seed yield were measured. Findings The results showed whit increasing severity water deficit stress, decreased total chlorophyll (chl a+b), chl a and b, relative water content and potassium, phosphorus and nitrogen content of grain, while increasing proline and essential oil content. Biofertilizer increased the total chl, chl a and b content, seed yield, essential oil percentage and essential oil yield and potassium, phosphorus and nitrogen content of grain. The highest seed yield were provided by nitroxin with biological phosphorus application (474.22 kg ha-1). Also, the interaction effect of biofertilizer and irrigation regime were significant on total chl, chl a and b, proline, potassium and phosphorus content of grain, so that the highest total chl, chl a and b content and potassium in seed were obtained in irrigation with 60 mm evaporation from pan and nitroxin whit bio- phosphorus application treatment. Conclusion Overall, the results showed that the use of nitroxin and bio- phosphorus fertilizer could improve essential oil percentage and essential oil yield (15.9% and 47%), seed yield (36.9%) and absorption of nitrogen (3.8%), phosphorus (21.9%) and potassium (10.4%) seeds in green cumin. Finally, it can be concluded that water deficet stress whit biofertilizers were suitable strategy for improve drug performance (essential oil percentage and essential oil yield) in green cumin and reducing environmental pollution. Keywords: Drought stress, nitoxin, bio- phosphorus, percentage and essential oil yield.
Mohammad Hadi Hosseinzadeh; Amir Ghalavand; Massoud Mashhadi Akbar Boojar; Seyed Ali Mohammad Modarres-Sanavy; Ali Mokhtassi-Bidgoli
Abstract
Introduction Water and nitrogen are among the key factors determining the yield of agricultural production around the world. Iran is dominated by arid and semiarid climate, with water availability presenting a great problem in many areas across the country. Water stress have altered plants’ metabolism ...
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Introduction Water and nitrogen are among the key factors determining the yield of agricultural production around the world. Iran is dominated by arid and semiarid climate, with water availability presenting a great problem in many areas across the country. Water stress have altered plants’ metabolism significantly, thereby attenuating the growth, photosynthesis, and ultimately yield of the plants. Accordingly, it is very important to identify the mechanisms through the plant adapts to various conditions and resists against stresses, and to understand possible ways to address such stresses. In addition, under such conditions, drought management is an essential necessity. Cultivating plants with lower water requirements is a solution for effective management of available water resources. Being largely adaptable to a wide spectrum of various weather conditions, purslane serve as an economically efficient product (both as vegetable and medicinal plant) in terms of water scarcity. Furthermore, in order to effectively manage water consumption in agriculture, adoption of various farming techniques, such as application of organic fertilizers or improving biological conditions of soil may render effective for reducing the impacts of water stress, while less use of chemical fertilizers may add to agricultural sustainability and health of medicinal plant. Material and methods In order to investigate the effect of combining different sources of nitrogen fertilizer (organic and chemical fertilizers) and mycorrhiza under drought stress on morphological and agronomic properties and also on Essential oil and oil contents of purslane leaves, experiments were performed in Zavariyan Village, Qom Province, Iran during 2015-2016, in the form of, factorial split plot in the base of randomized complete blocks and three replications. Factors include two water deficit stress (I1 without stress: irrigation time is when the amount of available water for plants on farm is 70% FC; I2 stress: irrigation time is when the amount of available water for plants on farm is 50% FC.) and two treatments mycorrhizal M1 inoculated and M2 non-inoculated with the fungus, as treatments the main factor and six sources of fertilizers, mixture of organic fertilizers (sheep and chicken) and chemical fertilizers including: (F1 without the use of organic fertilizers and chemical fertilizer, F2 including 100% organic fertilizers without the use of chemical fertilizers, F3 including 75% organic fertilizers and 25% chemical fertilizers, F4 including 50% organic fertilizers and 50% chemical fertilizers, F5 including 25% organic fertilizers and 75% chemical fertilizers, F6 without the use of organic fertilizers and 100% chemical fertilizers) as the sub factors. Results and discussion Results indicated that, during the first and second years of the experiment, drought stress reduced the height (13.8% and 16.4%), Mycorrhizal colonization (30.3% and 15.3%), phosphorus content of leaves (5.8% and 7.7%), Biological yield (21.3% and 17.7%), grain yield (22.5% and 21.1%), and total antioxidant capacity of the leaves (15.9% and 10.5%) of purslane. At the same time, production of secondary and medicinal metabolites (essential oil (6.2% and 5.4%) and oil concentration (48.7% and 57.9%) on the leaves of purslane increased. Application of mycorrhiza led to an increase in all of the considered properties due to its larger capacity for absorbing water and nutrients (phosphorous, in particular) and attenuating negative impacts of drought stress. The results also indicate that, maximum values of most of the considered properties in the treatments without stress were observed by mycorrhizal application and combined fertilizer (organic and chemical). Conclusions To sum up, it can be concluded that, if the aim of planting purslane is to use its growth and seed parts, the best results can be achieved upon adequately irrigating the plant while applying mycorrhiza and mixed nutrient system (50% organic fertilizers + 50% chemical fertilizers). However, should medicinal and qualitative aspects of the plant are concerned, drought stress treatment with mixed nutrient system (25% organic fertilizers + 75% chemical fertilizers) represent the most suitable treatment for enhancing secondary metabolites under stress conditions, highlighting the role of nitrogen as an essential element in the structure of the plant essential oil.
Marziye Askarnejad; Hamid Sodaeeizadeh; Asghar Mosleh Arani; Rostam Yazdani Biouki; Parizad Mavandi
Abstract
Introduction Abiotic stresses adversely affect agricultural productivity worldwide. In the arid and semi-arid areas, water is one of the most basic ecological units, which determines the growth and development of plants. Therefore, efficient use of water resources should be considered in order to achieve ...
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Introduction Abiotic stresses adversely affect agricultural productivity worldwide. In the arid and semi-arid areas, water is one of the most basic ecological units, which determines the growth and development of plants. Therefore, efficient use of water resources should be considered in order to achieve desirable plant growth. Aside different effective factors, minerals such as silicon are the most essential affecting the growth and development of plants. Silicon has beneficial effects on many crops, especially under biotic and abiotic stresses. Silicon can affect biochemical, physiological, and photosynthetic processes, consequently ameliorates drought stress. However, the effects of silicon on stevia (Stevia rebaudiana L.) plants under drought stress has not well known. Stevia is a branched bushy shrub of the Asteraceae family and originated from South America, and its cultivation has spread worldwide. Stevia is well known for its high content of sweet components. Materials and Methods The purpose of this research was to determine the effects of different silicon concentrations on physiological and morphological characteristics of stevia under drought stress conditions. The treatments were four levels of drought stress including: 25%, 50%, 75%, 100% pot capacity and three levels of silicon concentrations consisted of 0, 1, 1.5 mM, which arranged in a factorial experiment based on completely randomized design with three replications. After the plants establishment, drought treatments were imposed. After 40 days of applying drought treatments, silicon was twice sprayed with 7 dyas interval. The leaves of plants were sampled one week after the last spraying and transferred to the laboratory and the amount of soluble sugars, proline and chlorophyll concentrations were measured. In order to analysis data, analysis two-way ANOVA were used and Duncan test compared means after normality test. Statistical analysis was performed using SPSS software, and Excel software was used for drawing the charts. Results and Discussion Applying experimental treatments had only significant effect (p<0.01) on plant height, shoot fresh weight, canopy diameter, and canopy volume, while had no significant effect on shoot dry weight and number of leaves. The effect of silicon foliar application was significant on plant height, canopy diameter and canopy volume at 1% probability level and on shoot fresh weight and shoot dry weight at 5% probability level. The interaction between stress and silicon only was significant (p<0.01) on shoot dry weight, diameter and volume canopy, but had no significant effect on other traits. The results also showed that in no spraying, 1 and 1.5 mM silicon treatments under 25% FC significantly increased soluble sugars compared to 100% PC, so that the maximum amount of soluble sugars found in 25% FC and 1.5 mM silicon. Since the sugars are made from compatible osmolytes and its accumulation lead to osmotic adjustment, keep the cellular turgor and stability of protein. Thus increasing in soluble sugars such as sucrose, glucose and fructose as a result of environmental stresses, particularly drought are considered as a strategies of plants to tolerate adverse environmental conditions. Increasing drought stress to 25% PC significantly increased proline of stevia by 74% compared to the three levels of 100%, 75% and 50% PC. The results of several studies showed the positive effect of drought stress on proline, so that proline content is greater in drought stress than normal conditions. Increasing proline content in stress conditions might be due to increasing in activity of enzymes are responsible for the synthesis of this material, reducing the proline oxidation to glutamate and/or decreasing in consumption of proline in the process of making proteins. The results of evolution of different treatments of drought stress on chlorophyll content of stevia plant showed that the effect of drought stress was significant (p<0.01) on chlorophyll b, so that the most of chlorophyll b was observed in 75% PC treatment, which had no significant difference to 50% and 25% PC treatments, and the lowest was observed in 100% PC. Increasing inconsiderably chlorophyll b in drought stress conditions showed that chlorophyll pigments are somewhat tolerance to water loss. Conclusions The results of this experiment showed that height, shoot fresh weight of, diameter and volume of canopy, root volume, dry and root fresh weight of, and chlorophyll b were significantly decreased with increasing in drought stress level, however, using of both different silicon concentrations, especially 1 mM modulated damages of drought stress on stevia. Generally, the results of this research revealed the positive role of silicon in decreasing the negative effects of drought stress in stevia.
Ali Jalalvand; Babak Andalibi; Afshen Tavakoli; Parviz Moradi
Abstract
Introduction Drought is one of the most important environmental stresses that affects the morphology, physiology and biochemistry of the plant and it has a major impact on agricultural production. The Moldavian balm is herbaceous that originated in middle Asia and about 66 compound are identified in ...
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Introduction Drought is one of the most important environmental stresses that affects the morphology, physiology and biochemistry of the plant and it has a major impact on agricultural production. The Moldavian balm is herbaceous that originated in middle Asia and about 66 compound are identified in this plant. Application of growth regulator lead to increases of plant resistance against biotic and abiotic stress and is involved as a strategy to prevents adverse effects of environmental stress. According to semi-sensitivity of dragonhead plant to drought condition, its medicinal importance as well as, its industrial widespread use, this study was conducted to evaluate dragonhead essential oil yield and its compound under drought condition and also, to evaluate physiological aspect of drought resistance. Material and methods In order to investigate the effects of salicylic acid and cycocel on the gas exchange on Moldavian balm in drought stress condition research was conducted in the spring of 2014 and 2015 at research farm of agricultural college, Zanjan University. The experiment was laid out in split plot with two factors of moisture levels and growth regulators in a randomized complete block design with four replications. The main factor is the moisture levels at two levels without stress (Complete irrigation until the end of the growth period), drought stress (Complete irrigation before start flowering and discontinuation of irrigation until the end of the growth period). Sub-substrate of different levels of salicylic acid (800 and 1600 μm), cycocel (600 and 1200 μm), and control (dissolve with distilled water), which applied for a single application before start flowering. Findings The results of two-year combined analysis of variance showed that the interactions of the sampling stage in the year in moisture for leaf relative water content, canopy temperature, essential oil percent, essential oil yield, plant fresh weight and plant dry weight was significant at the 1% probability level. Mean interactions of growth regulator in during sampling stage showed the salicylic acid treatment (800 μM) at the end of flowering stage (H3B1) had the highest percentage of essential oil (0.37) and the lowest percentage of essential oil is related to the 600 micro molar (0.16) cycocel treatment at the flowering stage (H1B2). Conclusion The percentage of essential oil in the start flowering stages, flowering and flowering ends is increasing, so that the highest percentage of essential oil is associated with the flowering ends stage. Under stress conditions, the essential oil yield is reduced. Cycocel treatments 1200 micro molar it was caused by increased root growth and increased water absorption from the depths of the soil the plant has more essential oil than other treatments. In drought stress conditions, essential oil yield decreased and essential oil percentage increased. Also, by applying drought stress, the water status of the plant changes significantly and the relative water content of the leaves decreases. According to the results of the experiment, it can be concluded that drought stress reduced the yield and essential oil percentage of the Moldavian balm.The use of salicylic acid in conditions of drought stress compared to cycocel increases the yield and essential oil percentage.
Bahareh Kashefi; Faeze Bahri
Abstract
Introduction Drought stress is one of most common Non-biological tensions that it limits plant growth in arid and semi-arid. In arid and semi-arid regions, water deficiency is one of the factors limiting the growth of plants. Access to cultivars that can grow and develop high crop production under drought ...
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Introduction Drought stress is one of most common Non-biological tensions that it limits plant growth in arid and semi-arid. In arid and semi-arid regions, water deficiency is one of the factors limiting the growth of plants. Access to cultivars that can grow and develop high crop production under drought stress is very important. Hexaconazole in Triazole mixtures are new types of chemicals that with prevention kaoreen oxidase activity and gibberellin biosynthesis leads to vegetative growth reduction and generative growth increase .These compositions also are causes to raising splits numbers and reducing the growth. Malva sylvestris is a valuable medicinal plants, from the Malvasia family, is a one-year, two-year-old or seldom perennial herb. Materials and methods To evaluate Hexaconazole treatment effect on Malva sylvestris growth features under drought stress, an experiment was conducted in a completed randomized design as factorial in 4 replicate in the Neyshabour city. In plant phenological stage, in Four-leaf to five-leaf level water stress in witness and 50% of Field capacity and Hexaconazole treatment was applied in 3 levels with 0, 15 and 25 mg L−1 as leaf spray. The reaction of the plant was studied for about two months, then physiomorphological traits and antioxidant enzymes activity were measured. After performing the project and collecting data, statistical analysis was performed using SAS software. The mean comparison was determined by Duncan's multiple range test at a probability level of 1% and the correlation between traits was determined. Excel was also used to draw charts. Results and discussion the results of analysis of variance showed that the effects of drought stress and hexaconazole treatment had significant differences in most of studied traits at 1% probability level. Treatments causes to reduction stem length, root and leaf area and it increases root ratio to stem and wet and dry weight, density proline and catalase and peroxidase enzymes. It was also observed that the treatments do not effect on the number of leaves, chlorophyll a, b, and total and protein. Drought stress reduces turgor and disrupts division and prolongation of cells. Hexaconazole is an active member of the family of triasol, which has been shown to play a role in regulating plant growth. Hexaconazole has been shown to cause morphological and physiological changes in plants. Physiological effects of triazoles can be attributed to increasing chlorophyll content per unit area, reducing respiratory activity, increasing antioxidant activity and increasing plant resistance to stress. As the results of the study indicated, hexaconazole is effective in modulating the effect of drought stress on Malva sylvestris plant. Conclusion The results of this study showed that hexaconazole treatment decreased with growth leaf area and Number of leaves, increase shoot/ root growth rate, vegetative growth of shoot and root, fresh and dry weight, chlorophyll, soluble sugars, peroxidase and catalase enzymes and proline concentration, the plant's defense mechanism improves to drought stress. Also, It has been determined that plant growth regulator such as hexaconazole can be effective in the development of growth and the improvement of some plant characteristics and reduce plant stress.
Nasrin Heidari; Yaser Alizadeh; Hamzehali Alizadeh
Abstract
IntroductionEnvironmental stresses are considered as the most important limiting factors in agricultural production in the world. About two-thirds of Iran's agricultural lands are located in arid and semi-arid regions and face drought stress. After drying, salinity is one of the most important environmental ...
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IntroductionEnvironmental stresses are considered as the most important limiting factors in agricultural production in the world. About two-thirds of Iran's agricultural lands are located in arid and semi-arid regions and face drought stress. After drying, salinity is one of the most important environmental stresses in the world and in Iran. Environmental stresses have a negative effect on the growth and development of reproductive organs and decrease the economic and biological yeild of the plant. These stresses also affect many physiological processes of the plant and cause changes in plant physiological traits. Studies have shown that the absorption of the most of nutrients in plants under salt and drought stress is reduced. Nitrogen is the first food ingredient that is lacking in saline areas and is an essential nutritious element of the plant. Considering the major contribution of maize in providing human food, livestock and industrial uses, as well as soil conditions of the country, organic matter shortages and climate change, the comprehensive study of the mutual relations of consumption and non-use of fertilizers is essential in the presence and absence of water stresses and salinity, according to optimal management of water and soil resources and fertilizers and finally the achievement of optimal yields. Materials and methodsThe experiment was conducted as split- split plot design in a randomized complete block design with three replications at the Research Farm of the Faculty of Agricultural, University of Ilam in 2017. The treatments consisted of four levels of salinity (S1 =fresh water, S2 = 2, S3 = 4 and S4 = 6 ds / m) from salt rock source as the main factor, three levels of irrigation (I1 = 100, I2 = 80 and I3 = 60 percentage of water requirement of the plant) as a sub factor and three levels of nitrogen fertilizer from urea source (N1 = 0, N2 = 100 and N3 = 150 kg/ha) were considered as the sub- sub factor. Treatments were applied, in the 5_6 leaf stage. Sampling was performed to measure physiological traits at flowering time and yield and yield components at harvest time. Data analysis was performed by SAS.9.2 software and the mean comparison test was performed by LSD test. Charts is drawn by Excel. Results and discussionBased on the results, the highest yield was obtained in non stress conditions and application of 150 kg ha-1 nitrogen. Interaction of stresses among functional traits had the most negative effect in grain yield with a 69% reduction, also, among three physiological traits, electrolyte leakage showed a three-fold increase in the effect of interaction treatments with increasing tensions. The number of seeds per ear, number of rows per ear, number of seeds per row, biological yield and harvest index were decreased by 59%, 40.6%, 40%, 65% and 46%, respectively. Application of nitrogen at all levels of stress also reduced the effects of stresses and increased yield. The relative water content of leaf, chlorophyll a, chlorophyll b, total chlorophyll and carotenoid were also significantly reduced by the dual effects of treatments. It was also observed that all examined traits at the highest level of stress had an almost identical response to N2 and N3 treatments. Therefore, it seems that application of 100 kg ha-1 of nitrogen in maize under stress is appropriate for increasing the plant resistance and reaching maximum yields. ConclusionsThe results indicated that salinity and irrigation stress in all studied traits were significant. Increasing stresses increased ion leakage and decreased other traits. Nitrogen consumption under stress condition improved all traits. There was no significant difference between treatments for consumption of 100 and 150 kg ha-1 nitrogen except for biological yield. As a result, under severe stresses, consumption of 100 kg ha-1 of nitrogen seems to be more optimal.
Hadi Chamhidar; Roozbeh Farhoodi
Abstract
Introduction High salinity in soil or irrigation water is a common environmental problem affecting seed germination and plant growth. Salinity mainly causes hyper-osmotic stress and hyper ionic toxic effects; the consequence can be plant death .Salt and osmotic stresses are responsible for both inhibition ...
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Introduction High salinity in soil or irrigation water is a common environmental problem affecting seed germination and plant growth. Salinity mainly causes hyper-osmotic stress and hyper ionic toxic effects; the consequence can be plant death .Salt and osmotic stresses are responsible for both inhibition or delayed seed germination and reduced seedling establishment. Salt stress decreases germination percentage, shoot length and root length of canola cultivars. The increasing evidences also suggest that high salinity induces oxidative stress which is a key underlying component of most abiotic stresses. Reactive oxygen species (ROS) are generated as by-products of plant cellular metabolism and are also important as signaling molecules. This study aims to investigate the effect of salt stress on seed germination, seedling growth, antioxidants enzymes activities and ion concentration of canola cultivars. Material and methods The present study was conducted to investigate the influence of salinity on seedling growth, ion concentration and antioxidants enzymes activities in two separated experiment. The seeds of canola cultivars were obtained from the oil plant research Institute, Karaj, Iran. The experiment was carried out under a two-factorial (cultivar × salinity level) Sodium chloride was used as a source of salt. Salinity levels were 30, 60 and 90 mM NaCl solution and distilled water served as the control (0 ds/m) and four canola (B. napus L.) cultivars include Hayola 330, Hayola 320, Hayola 401 and sarigol. Ion concentration, antioxidants enzymes activates, seed germination, seedling growth, soluble carbohydrate and proline concentration were assay in this research. Results Salt stress decreased canola seed germination and seedling growth. At 60 mM NaCl treatment, maximum germination percentage obtained in Hayola 330 and Hayola 320 cultivars (76% and 77% respectively) and in 90 mM NaCl n, Hayola 330 had maximum germination percentage. Salt stress decreased seedling weight and in 90 Mm treatment, maximum dry weight obtained in Hayola 330 cultivars (1.72 g). Salt stress increased Na+ concentration and decreased K+ concentration in canola cultivars. Hayola 330 and Hayola 320 showed maximum K/Na ratio compared other canola cultivars in 60 mM and 90Mm NaCl treatments. Hayola 330 and Hayola 320 had higher antioxidant enemies activates, soluble carbohydrate and proline concentration compared Hayola 401 and Sarigol , too. Our results showed that salt tolerant cultivars have higher K+ concentration and K/ Na than salt sensitive cultivars. On the other hand, this study showed composite correlation between increase of K+ and decrease of Na+ with growth of rapeseed seedling. Salt-tolerant cultivars generally show higher activity of antioxidant enzymes and K/Na as compared to salt-sensitive ones This suggests that high antioxidant enzyme activity and ion concentration has a significant role in imparting salt tolerance in plants. Researchers suggested that K+ concentration observed in salt stress tolerant plants were more than that of susceptible cultivars led to decreased Na+ toxicity. Increased Na+ content led to decrease in seed germination level and seedling dry weight in canola cultivars. Proline and soluble carbohydrate are important osmoprotectant in plants. Under salt stress most plant species exhibit a remarkable increase in their proline and soluble carbohydrates content. In our experiments we also observed a similar behavior in the seedling of canola. Conclusion In conclusion, our data indicates that salt-induced oxidative damage occurs in canola cultivars despite concomitant increases in the activities of antioxidant enzymes. Hayola 330 and Hayola 320 were salt stress tolerant cultivars compared other cultivars because under salinity stress condition these cultivars had maximum K/Na, seedling dry weight and antioxidants enzymes activates. In fact, Hayola 330 and Hayola 320 cultivars were most salt tolerant due to maintenance of higher germination and seedling weight under saline conditions with maximum higher antioxidant enemies activates, soluble carbohydrate and proline concentration compared Hayola 401 and Sarigol. Our results indicated that Hayola330 and Hayola 320 cultivars had a higher capacity for the tolerant salinity in comparison with sensitive cultivars.
Masoumeh Salehi; Vali Soltani; Farhad Dehghani
Abstract
Introduction Phenological growth and development is very important for determination of sowing date and agronomic practices in different climate condition. Quinoa has been cultivated in the Bolivian and Peruvian Andean region for 7000 years. Worldwide interest on this crop is increasing because of high ...
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Introduction Phenological growth and development is very important for determination of sowing date and agronomic practices in different climate condition. Quinoa has been cultivated in the Bolivian and Peruvian Andean region for 7000 years. Worldwide interest on this crop is increasing because of high nutritional quality. Quinoa is gluten free peuduo cereal and suitable for celiac patients, and whole grain consumption prevent type 2 diabetes and because of low glycemic index can be replace common cereal in diabetes diet. Of more than 50 000 edible plant species in the world, only a few hundred contribute significantly to food supplies. Just 15 crop plants provide 90 percent of the world's food energy intake, with three rice, maize and wheat - making up two-thirds of this. Quinoa is a facultative halophyte plant species and some varieties are able to complete life cycle at 400 mM salinity. Quinoa growth was stimulated by moderate salinity (10 dS m-1). Quinoa is interest in Iran for high tolerance to abiotic stress and as a new crop for saline area. The aim of this study was selection of the best sowing date for early mature cultivar of quinoa. Material and methods For evaluation of different climate condition on phenological growth stage and seed yield, quinoa (NSRCQ1) was planted in eight sowing date (22 Aug, 6 Sep, 26 Sep, 7 Oct, 24 Oct, 24 Feb, 7 March and 30 March) with 14 dS m-1 saline water in Yazd, Iran. One of the main pests of the quinoa which was feed leaves during vegetative growth stage in all sowing date was Spodoptera exigua. This pest controlled by Avant and Saypermetrin. Growing degree day of different growth stage was calculated by dent-like function. Data was analyzed with randomized complete block model using SAS. Treatment means were compared using least significant difference (LSD) test at P=0.05. Results Results showed that quinoa produced 2.34 t ha-1 at the first sowing date and complete life cycle during 108 days. Frost damage occurred at -4.5 °C in 26 Sep sowing date at flowering stage. In Oct sowing date crop can survive during winter but could not produce the seed. Feb sowing date produced 1.6 t ha-1 and crop cycle complete during 132 days. High temperature (above 32 °C) in Feb and March sowing date and low temperature (13.6 °C) in Sep sowing date during grain filling period reduced seed yield and size. Flowering and seed filling stages were sensitive to photoperiod (based on phenological stage response to growing degree day). Quinoa (NSRC Q1) had a short day quantitative response to photoperiod and photoperiod longer than 12 hours prolonged time to flowering. Among the sowing dates 22th Aug was selected because of shorter growing cycle and higher seed production in Yazd provinces. Conclusion Among the growth stage grain filling period is sensitive to high and low temperature and the best temperature was 20 ºC. Flowering time and grain filling stage is sensitive to photoperiod and day length longer than 12 hours increased GDD requirement. In 22th Aug sowing date 560 mm saline water (14 dS m-1) was applied in Yazd. In spring sowing date growing cycle prolong to 132 days and seed yield and weight were lower than Aug sowing date. Plant produced higher biomass but during seed filling period high temperature reduced seed yield. For Central Plateau of Iran the best sowing date is in the late of Aug. Based on the weather and phenological data and weather data the best sowing date of this genotype for different agroecological zone could be predicted.
Azita Nakhei; Elias Arazmjoo; Mohammad Reza Abasi
Abstract
Introduction Salinity is one of the most important tensions in global agricultural production. About 20% of the irrigated lands are facing salinity problems in arid and semi-arid regions of the world, and salinity in these areas is increasing. In Iran, the salinity is about 44.5 million hectares, which ...
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Introduction Salinity is one of the most important tensions in global agricultural production. About 20% of the irrigated lands are facing salinity problems in arid and semi-arid regions of the world, and salinity in these areas is increasing. In Iran, the salinity is about 44.5 million hectares, which has varying degrees of salinity and alkalinity (Banaei, et al., 2005). Selection of salt tolerant genotypes in farmer conditions is a practical and dealing ways in using saline water and soil. Millet cultivation in Iran has a long history and according to the short growth period, is able to feed forage in conditions where other sources of forage are not available. The cultivated area in Iran is about 10,000 hectares (Aaron, 2006). According to recent studies, it is possible to develop plant cultivation in all regions of the country. The area under cultivation of this plant in the south khorassan province is about 1000 hectares and the cultivation of this plant has long been rooted in the culture of farmers in this area (Bina, 1993). According to the adaptability of this plant to unfavorable environmental conditions, soil poverty and environmental stresses that are characteristic of arid and semi-arid regions such as South Khorasan. One of the easiest ways to identify and selection of resistant genotypes is explosion to stress and selection the genotypes that tolerate these conditions better than the others.Materials and Methods In order to evaluation of salt tolerance in foxtail millet genotypes, two separate experiment with 15 genotypes in saline and none-saline conditions arranged in randomized complete block design with three replications conducted in two years of 2012 and 2013 at the Research and Education Center of Southern Khorasan. Combined analysis of variance showed that salt stress lead to a significant reductions in days to heading, days to maturity, plant height, panicule length, number of panicule per plant and thousand seed weight.In the end, after determining the grain and forage yield in stress and non stress conditions, MP, GMP, TOL, HARM, STI and SSI indices were calculated and using SAS software, correlation between the indices with grain yield and The dry forage was examined and using the SigmaPlot software, the three-dimensional distribution chart of each sample was plotted in A, B, C, and D ranges.Results and discussion Millet seed yield and dry forage yield in saline condition decrease about 40 and 38 percent, respectively. Genotypes number 15-118, 15-24 and 15-120 with averages of 3827.8, 3805.1 and 3803.2 kg/ha had the highest and number 15-80 with 1977.2 kg/ha had the lowest two year averages of yield, respectively. Results of correlation of seed yield and dry forage yield of millet genotypes in saline and none-saline conditions with tolerance and sensitivity indices revealed that STI, MP and GMP are the best indices for selection and recognition of salt tolerance genotypes of foxtail millet. Genotypes numbers of 15-24, 15-76, 15-118 and 15-120 indentified as the most tolerant genotypes to salinity stress on the basis of 3D scattering graph.
Daryush Talei; Abolfazl Reyhani
Abstract
Introduction Nigella sativa is an herbaceous and annual plant in the family of Ranunculaceae, which cultivated in different parts of Europe and Asia, including in Iran (various regions, especially Arak and Isfahan). The plant has small leaves and white flowers with blue margin. Salinity stress is one ...
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Introduction Nigella sativa is an herbaceous and annual plant in the family of Ranunculaceae, which cultivated in different parts of Europe and Asia, including in Iran (various regions, especially Arak and Isfahan). The plant has small leaves and white flowers with blue margin. Salinity stress is one of the major environmental stresses due to low osmotic potential of soil solution (osmotic stress), ionic toxicity (ionic stress) and nutritional disorder, or a combination of these factors in the plant as one of the most important factors limiting growth and development of plants. Materials and methods In order to study the morpho-physiological and biochemical responses of Nigella sativa plant to salicylic acid under salinity stress conditions a split plot experiment with two factors carried out based on completey randomized design with 3 replicates in the greenhouse of the Medicinal plants research center of Shahed University in 1396. The salinity factor with 4 levels (0, 3, 6, 9 dS/m) in main plots and salicylic acid levels in 4 levels (0, 25, 5 0 and 0.75 mM) were investigated in sub plots. Salicylic acid levels were sprayed on plants one week before applying salinity stress (about 4 to 6 leaves) and three weeks after salinity stress conditions. After 21 days of treatment, the effect of salinity stress on growth traits (shoot length, number of branches, number of leaves, root length, fresh and dry weight of shoot, fresh and dry weight of root), physiological traits (chlorophyll a, chlorophyll b and carotenoid, proline, malondialdehyde and catalase and superoxide dismutase were investigated. Results and discussion The results showed that different salinity concentrations had significant effects on morphological and physiological traits. By increasing salinity levels, the growth indices such as number of branches, number of leaves and chlorophyll b and the amount of superoxide dismutase and malondialdehyde decreased, while by increasing the salinity levels the content of proline and catalase in leaf increased. The results showed that applying salicylic acid under salinity stress reduced the growth indices and photosynthetic pigments. The highest number of branches, number of leaves and chlorophyll b was obtained at 3 dS/m salinity and 0.5 mM salicylic acid. Also, by increasing salicylic acid level, the activity of the proline content and leaf cattalase increased, but with increasing the salicylic acid levels, the amount of malondialdehyde and superoxide dismutase enzymes decreased. Based on the results, it can be concluded that the Nigella sativa is a semi-sensitive saline plant. The overall results showed that salicylic acid increased the plant tolerance to salinity stress. However, for a better conclusion on the effect of salicylic acid, the use of this compound is needed in a wider range. For example, in most of the studied physiological and biochemical traits, no significant difference was found between the effects of various salicylic acid concentrations. While positive effect of salicylic acid cannot be ignored in improving the damage caused by stress. Conslusion In general, the use of salicylic acid resulted improving in biochemical parameters and increased plant tolerance to salinity stress. Therefore, it can be concluded that applying the salicylic acid can be a suitable procedure to reduce the harmful effects of salt stress in Nigella sativa.
Sara Parande; Seyed Vahid Eslami; Majid Jami Al-Ahmadi
Abstract
Introduction Light is a vital component for photosynthesis and plays a significant role in the competitive ability of plants. The nitrogen response of competing plants may be affected by radiation availability and maximum potential growth rate, which determine plant N requirements. Shading reduces the ...
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Introduction Light is a vital component for photosynthesis and plays a significant role in the competitive ability of plants. The nitrogen response of competing plants may be affected by radiation availability and maximum potential growth rate, which determine plant N requirements. Shading reduces the light intensity, which leads to changes in the morphology, physiology, biomass, grain yield, and quality of crops. Moreover, shading stress delays flowering and decreases biomass and grain yield. Since photosynthesis results in dry matter accumulation, and reduced light is known to limit carbon accumulation and nitrogen content, understanding these processes in weeds may provide insight as to their effects on crop production, help to predict their occurrence, and ultimately provide the needed information for their management. Materials and Methods In order to evaluate foxtail millet competition with pigweed at different levels of radiation and nitrogen, two separate experiments were conducted in split plot arranged in randomized complete block design with three replications at the Research Farm of Birjand University in 2015. Texturally the soil was loam, with 8.16 pH, 0.03% total N, 12 ppm available P and 250 ppm available K. The experiment was laid out in a split-plot design with three replications having three shade levels (0, 41 and 75% shade) in main plot and three pigweed density (0, 12 and 24 plant per square meter) in subplots in two separate experiments, one under nitrogen application and the other without nitrogen usage. In 0% shade treatment, sunlight was allowed to fall over the millet and pigweed without any barrier. In 41% and 75% treatments, however, the light levels in the form of PAR were reduced using shade nets. At the end of growth stage millet traits including days to panicule emergence, days to maturity, grain filling period, number of grain per panicule, 1000 grain weight, grain yield, forage yield, biomass and harvest index were measured. Data analyses were performed using two-way analysis of variance (ANOVA) with SAS 9.1. Means of treatments were compared between nitrogen, shade treatments and pigweed densities according to protected least significance difference (FLSD) test at the 5% level. Results and Discussion Nitrogen had a significant effect (P < 0.01) on days to panicule emergence, days to maturity at 1% probability level and on grain filling period and grain yield at 5% probability level. Application of 150 kg nitrogen per hectare led to improvement of phenological traits and grain yield of millet. Nitrogen can extend vegetative growth stage period of plants and reduce grain filling rate (Nezamzadeh et al., 2011). Also, nitrogen fertilizer can increase grain formation and grain yield through improvement of photosynthesis ability owing to increases in leaf area index and leaf area duration (Moosavi et al., 2015). Shading had a significant (P < 0.01) influence on millet phenological traits and grain yield and had a significant effect (P < 0.05) on number of grain per panicule. Shading at level of 75% dramatically reduced number of grain per panicule and grain yield of millet while increased days to panicule emergence, days to maturity and grain filling period. Nasrollah-zadeh et al., (2011) also reported that grain filling period of faba bean increased by 3-4 days in shaded plants in comparison with control. With shading stress at its highest level, grain yield was significantly reduced by 61% from 3.70 to 1.44 ton per hectare. The effect of pigweed density on grain yield (P < 0.05) and plant height and stem diameter was significant (P < 0.01). The effect of pigweed density was also significant on forage yield (P < 0.01) and days to panicule emergence and grain yield (P < 0.05). Pigweed density of 24 plants per square meter led to 21% reduction in millet grain yield against control. The interaction between nitrogen and pigweed density on millet traits was limited, and only significantly (P < 0.05) affected grain yield. In competition of crops and weeds, the space required for crop to expand the leaf area decreases, and the competition between the species increases to absorb the active photosynthesis radiation. Under these conditions, less assimilates are transmitted to the reproductive organs, which has a profound effect on reduction in grain yield and further on harvest index (Gholamhoseini et al. 2015). Conclusions The results of this study showed that the grain yield of foxtail millet reduced by 61 percent with increasing of shading intensity contrasting with no shading. This reduction was due to the negative effects of shading on the number of grain per panicule and 1000-grain weight. Harvest index also decreased with increasing shading levels. The reduction in harvest index was due to a greater reduction in grain yield contrasting dry matter production at shading treatments. Also, grain yield at the highest level of pigweed density was 21% lower. These results, considering the importance of weed control, show that proper management of weed control in the field by providing conditions to faster closing canopy in order to reduce the competition of pigweed can be effective in grain yield improvement of foxtail millet.
Shiva Tohidi; Ahmad Gholamalizadeh; Mohamadreza Asgharipour; Hormoz Naghavi
Abstract
Introduction Industrial pollutants entering into the soil leads to the accumulation of excessive heavy metals such as lead, cadmium, copper and zinc in the soil. Phytoremediation is a method to remove heavy metals from the soil. Phytoremediation is one of the most important methods and technologies has ...
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Introduction Industrial pollutants entering into the soil leads to the accumulation of excessive heavy metals such as lead, cadmium, copper and zinc in the soil. Phytoremediation is a method to remove heavy metals from the soil. Phytoremediation is one of the most important methods and technologies has been developed during the last two decades to solve the problem of metal pollution in different countries, Where the cultivated plants to clean, absorb and remove contaminants from the soil is presented. The chemical reaction of metals in soil is one of the key issues in the discussion of phytoremediation of heavy metals so in phytoremediation using chemical and organic substances increase the solubility of contaminants and in this way to improve the efficiency of the refining of pollutants by plants. Add chelating agents can increase the efficiency of metal uptake by plants. Soil application of chelating agents Such as Ethylene diamine tetra-acetic acid, increased the concentration of metals Such as lead in plants through increased solubility of metal and increased transfer it from the roots to stems. Ammonium molybdate has the ability and potential to precipitate Pb and Zn and reduces the toxicity of these metals in the plant. Ammonium molybdate has ability to producing chelate to form more soluble sections with Cd, Cu and Ni, this feature increases the bioavailability of these metals to the plant. The objectives of this study are evaluation of the effects of ammonium molybdate to increase the bioavailability of lead in corn plant and compare it with Ethylene diamine tetra-acetic acid for the removal of contaminants from the soil. Materials and Methods For this experiment was conducted in a completely randomized design with factorial arrangement with three replications in greenhouse of Agriculture and Natural Resources Research Center of Kerman province, Iran. Experimental factors included four levels of lead (zero (Pb0), 150 (Pb1), 300 (Pb2) and 450 (Pb3) milligrams of lead per kilogram of soil from the source of lead chloride) and two types of chelating agents, Ammonium Molybdate (concentration of Mo 10 mg per kg of soil) (AM) and Ethylene diamine tetra-acetic acid (one gram per kilogram of soil) (E) and control. Some of the physical and chemical properties of the soil were measured. In order to contaminated samples of soil, the required value of lead, Ethylene diamine tetra-acetic acid and ammonium molybdate were added to the soils by spray method. After preparing the soil samples, the seed of corn plant (Zea mays L.) was cultivated in soils contaminated by experimental treatments. After harvesting, plant samples transfer to the laboratory, was dried, weighed and milled. Plant samples were digested by dry digestion and were measured the amount of lead in the shoots and roots. Soil samples were transferred to the laboratory for next analysis. Parameters was measured such as dry weight of shoot and root, the concentration of lead in shoot and root, absorption of Pb in shoot and root and availability of Pb in soil by DTPA method. Analysis was performed by using SAS statistical software and figures were drawn in Microsoft Excel. Results and discussion The highest available lead content in soil (extracted by DTPA) is related to Ethylene diamine tetra-acetic acid treatment which it was higher than 29.5% compare to control. The results showed that different levels of lead and form chelates have significant effect (p<0.01) on dry weight of root and shoot, relative concentration of lead in root and shoot and total absorption of lead in root and shoot. Ammonium molybdate was significantly increased dry weight of root and shoot. According to the results of the highest dry weight of root and shoot of corn plant is related to the level of unleaded (Pb0), the chelate of ammonium molybdate. The highest relative concentration and total absorption of lead in root and shoot was obtained Ethylene diamine tetra-acetic acid-treated at 450 mg per kg of lead (Pb3). Ammonium molybdate compared with Ethylene diamine tetra-acetic acid had a less ability to absorption of lead. Conclusion Obtained results of the comparison amounts of lead of roots and shoots of plants under the effect of use of ammonium molybdate and Ethylene diamine tetra-acetic acid, showed that Ethylene diamine tetra-acetic acid was more effective in increasing concentrations of the element in the corn plant.
Volume 12, Issue 3 , October 2019, Pages 988-988
