Mehdi Naghizadeh; Rozita Kabiri
Abstract
Introduction Drought stress is one of the most important environmental factors that regulate plant growth and development, and limit plant production. Salicylic acid is a growth regulation which its role was investigated in plants tolerance to environmental stresses such as drought stress. Therefore, ...
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Introduction Drought stress is one of the most important environmental factors that regulate plant growth and development, and limit plant production. Salicylic acid is a growth regulation which its role was investigated in plants tolerance to environmental stresses such as drought stress. Therefore, the objective of present research was to evaluate the effect of foliar application of salicylic acid on response to drought stress in maize. Materials and methods In order to evaluate some physiological and biochemical responses of maize hybrid SC704 to foliar application of salicylic acid under drought stress conditions, this field experiment was carried out at the green house of College of Agriculture, University of Shahid Bahonar, in 2013 in a factorial using completely randomized block design with six replications. Experimental treatments were salicylic acid (0 and 1 mM) and drought stress. Evaluated traits were including plant height, plant fresh weight, plant leaf area, electrolyte leakage, relative water content, photosynthetic pigments and antioxidant enzymes (including ascorbate peroxidase, catalase, peroxidase). Results The results showed that drought stress (70 and 50% F.C.) significantly reduced relative water content, chlorophyll a, b and total chlorophyll, fresh weight, length and leaf area of maize. However, the effect of 50% F.C. was more pronounced. Furthermore, results of this experiment also showed that drought stress increased electrolyte leakage as well as antioxidant enzymes such as catalase, peroxides and ascorbate peroxides of maize leaf. In contrast, foliar application of salicylic acid significantly increased relative water content, chlorophyll a, b and Total chlorophyll, fresh weight, length and leaf area of maize as well as catalase, peroxides and ascorbate peroxides and also reduced electrolyte leakage. Furthermore, salicylic acid caused the reduction of 20 percent in electrolyte leakage at the highest level of drought stress. Conclusion Salicylic acid with the maize plant protection against drought stress caused growth improvement and increasing of tolerance to stress and finally, with regard to the cost and availability of salicylic acid, the application of this exogenous protection compound can be a method to cultivate maize plant in drought stress regions.
Esmaeil Rezaei-Chiyaneh; Alireza Pirzad; Bahman Hosseini; Seyed Hadi Madani
Abstract
Introduction Ajowan (Carum copticum L.) is an annual plant and herbaceous belonging to the Apiaceae family (Majnoon Hosseini and Davazdah emami, 2007). The main component of ajowan essential oil is Thymol. Other main components of seed oil include α-pinene, β-pinene, p-cymene, γ-terpinene, ...
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Introduction Ajowan (Carum copticum L.) is an annual plant and herbaceous belonging to the Apiaceae family (Majnoon Hosseini and Davazdah emami, 2007). The main component of ajowan essential oil is Thymol. Other main components of seed oil include α-pinene, β-pinene, p-cymene, γ-terpinene, p-cymine and limonene (Majnoon Hosseini and Davazdah emami, 2007). Irrigation scheduling based on developmental stage or deficit irrigation is the technique of applying water on a timely and accurate basis to the crop, and is the key to conserving water and improving irrigation performance and sustainability of irrigated agriculture (Omidbaigi, 2009). Water stress substantially alters plant metabolism, decreasing plant growth, yield and photosynthesis but in some medicinal plants increase active substances such as essential oil (Bettaieb et al., 2009; Rebey, 2012). Heidari et al (2012) indicated that seed yield and essential oil yield affected by water stress and during maturation stages and found great differences in the essential oil percentage. Rezaei- Chiyaneh (2011) reported that number of umbels per plant, number of seeds per umbels, 1000-seed weight, biological yield, seed yield and essential oil yield significantly decreased with increasing irrigation intervals, but essential oil percentage increased. Despite considerable studies on the effect of drought stress on field crops the information on the behavior of the aromatic and medicinal plants has not been well investigated under water deficiency. Therefore, the main objective of the present study was to find out the effect of water deficit and harvesting time on the performance of plant and change in oil Ajowan in during stage of maturity. And so, it can be determine the optimal irrigation level and harvest time to maximize the seed yield and essential oil content. Materials and methods Field experiment was conducted at the farm located in West Azerbaijan province- city Nagadeh, Iran (latitude of 36, 57' and longitude of 45, 24’ at an altitude of 1328 m above mean sea level) during growing reason of 2010-2011. Treatments included irrigation (Irrigation after 60, 90, 120, 150 and 180 mm evaporation from class A pan) as main plots and harvesting time (milky, dough and maturity stages) as subplots were arranged as split plot based on randomized complete block design with three replications. Mean annual temperature and rainfall were 12.40 ˚C and 323 mm, respectively. The soil was clay- loam. Each plot size was 3.2 m× 4m involving 8 rows with 40 cm between rows and a distance of 25 cm between plants in the row on April 4, 2011. Basic fertilization was applied at the time of soil preparation at rates of 100 kg/ha N and 150 kg/ha p2o5. Weed control was performed manually. Also a block distance the main plot 1.5 meter and three-meter distance between the two blocks were considered to have an effect on both the moisture adjacent plots. The essential oil was isolated from 3o g of the fruits by conventional hydro-distillation for 3 h according to the method described in British Pharmacopeia. The essential oil content was calculated as a percentage. SPSS software was used for statistical analysis. To compare the means of Duncan's multiple range test at 5% probability level was used. Result and discussion Results of ANOVA showed the significant effect of irrigation on the plant height, number of umbels per plant, number of seeds per umbels, 1000-seed weight, biological yield, seed yield, essential oil percentage and essential oil yield. All the mentioned traits significantly decreased with increasing irrigation intervals from 60 to 180 mm evaporation. The highest yield of seed (1074 kg.ha-1) and essential oil yield (39.63 kg.ha-1) were achieved by irrigation after 60 mm evaporation. The effects of harvest date on the number of umbrella per plant, 1000-seed weight, biological yield, grain yield, essential oil percentage and essential oil yield were significant. The highest seed yield (931 kg.ha-1), essential oil percentage (4.35%) and essential oil yield (40.13 kg.ha-1) were obtained in dough stage. Telci et al (2009) compared the variation of fennel fruit essential oil composition during maturation stages and found great differences in the oil composition. Conclusion Increasing irrigation intervals from 60 to 180 mm evaporation resulted in decreasing plant height, umbels per plant, seeds perumbel, seeds per umbelet, 1000-seed weight, biological yield, seed yield and essential oil yield. Since irrigation after 90 mm evaporation of the irrigation after 60 mm evaporation of grain produced no significant difference and stage of dough showed higher performance. Therefore, it is recommended that to maximize essential oil production and achieve acceptable performance of Ajowan plant, it would be grown under moderate water deficit stress and be harvested at hard dough stage.
Ahmad Nemati; Mohammad Rafieiolhossaini; Abdolrazzagh Danesh-shahraki
Abstract
Introduction Grain of legumes, by having high protein percentage, is quality complementary of cereals grain. Among environmental stresses, water deficit is the most important factor which cause limitation of planting and yield loss of food crops. Organic fertilizers, in addition to the nutritional properties, ...
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Introduction Grain of legumes, by having high protein percentage, is quality complementary of cereals grain. Among environmental stresses, water deficit is the most important factor which cause limitation of planting and yield loss of food crops. Organic fertilizers, in addition to the nutritional properties, are effective in improving the physical and biological properties of soil. According to the positive outcomes of using rhizobim inoculants including, increasing the quantity and quality of the crop, improving growth indices, reducing nitrate concentration in agricultural products and groundwater and environmental protection, this research was designed and conducted to investigate the effect of bacterial inoculation and cow manure on characteristics of chickpea (Hashem variety) under drought stress conditions, and promotion of environmentally friendly fertilizers. Materials and methods The experiment was done during 2012-2013 growing season at the research field of the faculty of agricultural, Shahrekord University as split factorial in a Randomized Complete Block Design (RCBD) with 3 replications. Levels of drought stress including: 80, 100 and 120 mm evaporation from class A pan, were used as main plot factor while factorial combination of cow manure at three levels 0, 50 and 100% of plant complete need (20 ton/ha) and two levels of seed bacterial inoculation (Mesorhizobium) (inoculation and non-inoculation) were used as sub-plots. To determine the time of irrigation, the daily evaporation from evaporation pan was measured every evening and after reaching the desired level, irrigation was performed using flushing procedure. Results and discussion The results showed that by increasing drought stress intensity, the rate of crop growth rate and leaf area index was decreased. CGR and LAI significantly increased in inoculation treatment compared to non-inoculated. Means comparison showed that with increasing stress intensity, all of the yield components significantly decreased but grain protein percentage increased. Increasing consumption of cow manure and inoculation of bacteria caused increasing of grain yield components and its protein. Means comparison of the dual effects of drought stress × bacteria inoculation showed that bacterial inoculation significantly increased the number of pods per plant at all drought stress levels. Means comparison of the dual effects of cow manure × bacteria inoculation showed that inoculation caused increasing the number of pods per plant at all cow manure levels. The maximum hundred seed weight achieved at 20 tons/ha of cow manure treatment and bacterium inoculation. The results of the triple effects showed that the maximum hundred seed weight achieved at control × 20 tons/ha of cow manure × bacterium inoculation. With increasing severity of drought stress, grain yield and biological yield significantly decreased. The maximum and minimum grain and biological yield on the consumption of cow manure obtained in 20 tons of cow manure per hectare and no use of cow manure, respectively. Bacterial inoculation was significantly increased grain and biological yield. The results of the dual effects of cow manure × bacterium inoculation on grain yield, biological yield and harvest index showed that the maximum mean of grain and biological yield obtained at no use of cow manure × bacterium inoculation. The results of the triple effects on grain yield showed that the maximum grain yield achieved at bacterium inoculation × no use of cow manure × control. Conclusion Generally in this study it can be stated that the treatment of drought stress and bacterium inoculation have more effect on physiological indices, yield and grain yield components of chickpea. Drought stress causing reduction of photosynthetic sources and limitation of assimilate and thus leads to reducing hundred grain weight and leaf area and thus slow down the crop growth rate. In this experiment, it was found that the use of bacteria in drought stress conditions cause adjusting the effects of stress, therefore it is suggested that in areas where there is a likelihood of drought stress, the inoculated seeds should be used.
Ali Nakhzari Moghaddam; Ahmad Gholami
Abstract
Introduction Raey et al. (2008) reported that irrigation was affected on traits such as number of pods per plant, 1000-seed weight, seed yield and harvest index. Nayer et al. (2006) believed that flowering and pod setting are sensitive stages to water stress in chickpea (Cicer arietinum L.). water stress ...
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Introduction Raey et al. (2008) reported that irrigation was affected on traits such as number of pods per plant, 1000-seed weight, seed yield and harvest index. Nayer et al. (2006) believed that flowering and pod setting are sensitive stages to water stress in chickpea (Cicer arietinum L.). water stress in pollination stage reduced severity yield and phosphorous concentration of chickpea seed relative to vegetative stage (Gunes et al., 2006). Yazdani et al. (2009) studied effect of phosphate solubilisation microorganisms and plant growth promoting rhizobacteria on corn plant and reported that application of PSM and PGPR were increased yield of corn and phosphorous needs to 50%. The aim of this study was to determine the effect of inoculation with various mycorrhiza fungi and irrigation management on quantity and quality characteristics of chickpea (Cicer arietinum L.). Matherials and Methods In order to study the response of chickpea inoculated with different mycorrhizal fungi under different irrigation management, a split plot experiment based on Randomized Complete Block Design carried out with four replications on farm research of Industrial University of Shahroud in Bastam (36° 30′ N, 55°00′ E, and 1380 m above sea level) during 2011. Four levels of irrigation management (as main plots) was complete irrigation, non irrigation in flowering stage, non irrigation in pod setting stage and non irrigation in seed filling stage. Three levels of inoculation (as sub plots) was inoculation with Glumos mosseae, inoculation with G. intraradices and non inoculation. Planting of the seeds was done during the 2nd week of April 2011. Sowing was performed manually. Row spacing was 30 and within rows was 10 cm (333000 plants/ha). The experimental plots were 6 rows. Weed control was performed manually. Seed yield was determined by harvesting of each crop from 4 middle rows after removing of two border rows and 0.5 meter from two sides of remains rows in 2nd week of July 2011. Data were analyzed using the SAS Ver. 9.1 computer software program and treatment mean differences were separated by the least significant difference (LSD) test at the 0.05 probability level. Results and Discussion The results showed that the effect of irrigation management on number of pods per plant, number of seeds per plant, 100-seed weight, Grain yield, harvest index, protein percentage, protein yield, phosphorus concentration and phosphorus yield were significant so that the most of the traits except protein was obtained from complete irrigation treatment. Differences between complete irrigation and non irrigation at seed filling stage in terms of number of pods per plant and number of seeds per plant was not significant. The effects of inoculated with mycorrhiza on all traits except number of pods per plant, number of seeds per plant and protein percentage of seed was significant and the most amounts of the traitss was obtained from inoculation with G. mosseae and the lowest belonged to non-inoculation treatment. Differences between two inoculated treatment of G. mosseae and G. intraradices in terms of 1000-seed weight was not significant. The interaction of water stress × inoculation with mycorrhiza was not significant. Seed and protein yield in complete irrigation was 2651 and 557.3 kg/ha and in non irrigation in flowering stage was 1472 and 337.3 kg/ha, respectively. Seed and protein yield in inoculation with Glumos mosseae was 2124 and 495.2 kg/ha and in non inoculation treatment was 1677 and 391.9 kg/ha, respectively. Conclusion Vegetative, Reproductive and quality traits was affected by irrigation management. water stress decreased all traits and earlier water stress had more effec on yield. Effect of inoculation was less than water stress and inoculation with G. mosseae had more effect than G. intraradices on traits.
Ghazaleh Biriyay; Khodadad Mostafavi; Manoochehr Khodarahmi
Abstract
Introduction Diallel crosses can be used to study the gene action and heterotic grouping and patterns. In the recent decade, use of graphical approach or GGE biplot in the investigation of genotype × environment has become more common in breeding programs. In this method, the effect of genotype ...
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Introduction Diallel crosses can be used to study the gene action and heterotic grouping and patterns. In the recent decade, use of graphical approach or GGE biplot in the investigation of genotype × environment has become more common in breeding programs. In this method, the effect of genotype and genotype and environment interaction are broken and stable cultivar selection is done basis of both effects. When GGE biplot was used for diallel data, each genotype reviled as both line and tester. Also in this case, average performance and stability of genotypes equivalent with the parent GCA and SCA respectively. Biplot method very useful tool for visual assessment and interpretation of the parent’s pattern, the environment and their interaction. The aim of this study provides the following information for wheat base graphical methods: (1) Set parental general combining ability, (2) Estimates specific combining ability for hybrids, (3) Determine the adequate testers for future research, (4) Determine the best hybrids, (5) Determine of heterotic group and patterns among genotypes. Materials and Methods In this study, seven varieties of wheat including Alamut, C-84-12, Gaspard, Ghods, Moghan 1 and Afshar (as parents) were used. These varieties with 21 genotypes of F1 generation of them base half diallel (without reciprocal crosses) in 2012-2013 crop year on research farm of Agriculture and Natural Resources, Islamic Azad University of Karaj, in drought stress condition were cultivated. A randomized complete block design with three replications was used. To analysis of variance SAS software and for Diallel analysis D2 software were used. Graphical analysis according to Yan and Hunt method done with GGE biplot software. In order to evaluate the diallel results in bread wheat, biplot method was used. In this study, 12 agronomic traits, including Grain yield, Plant height, Spike length, Spike Weight, Stem diameter length, Awn length of the second internodes, Peduncle length, Extrusion peduncle, Seed length, Seed size and 1000 Seedweight were examined. Results and discussion Analysis of variance showed significant differences for most of the traits. General combining ability mean squares for all the traits except plant height, length of the second internodes and stem diameter was significant. Specific combining ability mean squares for all traits except stem diameter was significant at the one percent probability level. The highest and lowest average grain yield for parents was observed for Hamoon and Afshar cultivars and for hybrids observed for crosses the Hamoon × Ghods and C-84-12 × Gaspard. The most significant positive GCA for grain yield, was reviled for Hamoon variety. The most significant SCA for grain yield per square meter, observed for Hamoon × Ghods and C-84-12 × Moghan1. For spike weight, the highest and significant SCA values observed for Afshar × C-84-12 and Alamut × Gaspard. For grain weight the highest SCA observed for Alamoot × Ghods and Afshar × C-84-12. For spike length, Alamoot × C-84-12, Ghods × C-84-12, Afshar × Gaspard and Ghods × Moghan1 had a positive and significant SCA. Based on the results of diallel analysis biplot for grain yield of the lines, Cultivars Alamut and Afshar respectively, have a highest and lowest general combining abillity. Cultivars C-84-12, Ghods, and Gaspard has a specific combining ability were higher than other lines. Cultivars were divided into two groups. The first group includes Cultivars Gaspard, C-84-12 and Hamun, second group includes Alamut, Ghods, Moghan1 and Afshar. Testers Ghods, Alamut, C-84-12 and Gaspard similarities and relationships more than other tester for grain yield. Cultivars Ghods, C-84-12 and Alamut had more discriminating effect than other varieties. Conclusions In total, there were significant genetics diversity between cultivars that cause of the additive and non-additive effects in the studied traits such as yield. Comparing the results of numerical analyzes with graphical results represents the good conformity between of these two methods. Due to preferable of graphical methods in terms of faster and simpler interpretation for results, the use of these methods, to facilitate the investigation, recommended.
Abolfazl Zabihi; Abdollah Darzi-Nafchali; Mojtaba Khoshravesh
Abstract
Introduction Proper water management is the most important operation in paddy fields which plays a fundamental role in the usefulness of other inputs in rice cultivation. Mid-season and end-season drainages are two major water management practices in paddy fields so that, the former increases crop yield ...
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Introduction Proper water management is the most important operation in paddy fields which plays a fundamental role in the usefulness of other inputs in rice cultivation. Mid-season and end-season drainages are two major water management practices in paddy fields so that, the former increases crop yield and the latter provides more suitable conditions for rice harvest. Providing better condition for winter cropping in the fields, subsurface drainage can also facilitate such management practices during rice growing season. Field experiments should be done to quantify the effects of different water management strategies. However, with regard to the high cost- time consuming field experiments, simulation models are suitable alternative tools for analyzing the effects of different water management options. Among various simulation models, the AquaCrop model is a newly developed model for simulating the effects of irrigation management. This model is accurate, robust and requires fewer input data compared with the other models. AquaCrop has a water-driven growth engine for field crops with a growth module that relies on the conservative behavior of biomass (B) per unit transpiration (Tr) relationship. Another distinctive feature of the model is the expression of canopy development as canopy cover rather than leaf area index (LAI). Farahani et al. (2009) investigated full and deficit irrigation regimes on cotton using AquaCrop model in Syria and Spain. They showed that, for calibration, the key parameters such as normalized water productivity, canopy cover and total biomass, must be tested under different climate, soil, cultivars, irrigation methods and field management. In Italy, sunflower was studied using AquaCrop, CropSyst, and WOFOST models. There was less variation between observed and simulated grain yields by AquaCrop model than that of the other two models. Materials and methods In this research, using AquaCrop model, the effects of drought stress were investigated in surface- subsurface drained paddy fields. Required data were obtained from subsurface drainage pilot of paddy fields of Sari Agricultural Sciences and Natural Resources University during 2011 and 2012 rice growing seasons. The ETo was accounted with the use of ETo calculator 3.1. The inputs values for daily weather parameters were maximum air temperature (Tmax), minimum air temperature (Tmin), maximum relative humidity (RHmax), minimum relative humidity (RHmin), sunshine hours (n/N) and wind speed at a height of 2 m (u2) based on weather station data and the ETo Calculator was based on FAO website. Drainage treatments were: three conventional subsurface drainage systems including drainage system with drain depth of 0.9 m and drain spacing of 30 m (D0.9L30), drain depth of 0.65 m and drain spacing of 30 m (D0.65L30), and drain depth of 0.65 m and drain spacing of 15 m (D0.65L15); a bi-level subsurface drainage system with drain spacing of 15 m and drain depths of 0.65 and 0.9 m as alternate depths (Bilevel), and surface drainage system (Control). Calibration and validation of the model was performed using field measurements. Using the calibrated model, the effect of full irrigation (I1) and drought stress during 16-22 (I2), 23-29 (I3), 30-36 (I4), 37-43 (I5) and 44-50 (I6) days after rice planting on yield and water use efficiency of rice and root zone salinity was investigated. Results and discussion Drought stress in I2, I5 and I6 periods caused considerable decrease in rice yield and biomass compared to I1. The stress at the stages close to the heading, resulted in more reduction in rice yield so that the average rice grain yield loss due to drought stress in the I2 to I4 periods was 5% while, it was 15% due to stress in I5 and I6 periods. Drought stress in I2 period increased water use efficiency of surface and subsurface drainage treatments. In Bilevel subsurface drainage system (drain spacing of 15 m and and drain depths of 0.65 and 0.9 m), the applied water and water use efficiency were, respectively, 620.4 mm and 0.65 kg m-3 under full irrigation and 529 mm and 0.71 kg m-3 under drought stress during I3 period. Drought stress caused further increases in the root zone salinity in surface drainage system compared with subsurface drainage systems. Conclusion Based on the results, AquaCrop model could be used to determine the most appropriate water management system for rice cropping in terms of yield, water use efficiency and root zone salinity.
Zahra Majidi; Gholam Ali Ranjbar; Nadali Babaeian Jelodar; Nadali Bagheri
Abstract
Breeding of rice varieties tolerant to salinity is a solution for better exploitation of saline soils. Using mutation breeding methodology with potential of providing high genetic diversity can helps to improve a number of important economic traits. For such purpose rice cultivar Tarrom mahali was treated ...
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Breeding of rice varieties tolerant to salinity is a solution for better exploitation of saline soils. Using mutation breeding methodology with potential of providing high genetic diversity can helps to improve a number of important economic traits. For such purpose rice cultivar Tarrom mahali was treated by two chemical mutagens namely Ethyl Methane Sulfonate (EMS) and mix of Nitrous Urea Methyl + Sodium Azide (NUM+AZ). In second generation plants with desirable economically important traits were chosen and put under salt stress treatments in the third generation. In order to evaluate response of mutant lines to salinity in seedling stage a factorial experiment was conducted based on completely randomized design with 3 replications using a hydroponic medium with zero and 12 dsm-1. According to results two EMS treated mutant lines having high biomass and low Na/K ratio together with Nunabukra variety were stayed at tolerant group, in which, in comparison with non-mutant cultivar Tarrom mahali showed better performance in salt stress conditions and two salt susceptible lines were also obtained under this. While most of mutant lines in Nitrous Urea Methyl + Sodium Azide treatment were sensitive to salinity stress.
Nasibeh Abdolahzadeh; Reza Fotovat; Farid Shekari; Seyed Mohammad Alavi Siney
Abstract
Salinity is a major abiotic stress affecting agricultural production. Barley is one of the most tolerant species among glycophyte plants to salt stress. High tolerance of barley to salinity stress is related to its rapid phonological growth and development. Understanding of growth and development of ...
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Salinity is a major abiotic stress affecting agricultural production. Barley is one of the most tolerant species among glycophyte plants to salt stress. High tolerance of barley to salinity stress is related to its rapid phonological growth and development. Understanding of growth and development of different organs of plant, especially root, is important for optimal management of halophytes (Chen et al., 2008). Root systems can exhibit enormous plasticity on the level of biomass, morphology, and or physiology in response to different environmental parameters such as water and nutrient availability. Because root system traits, such as water uptake rates per surface area, are defined by the properties of individual root segments detailed studies about the abundance, morphology, anatomy, and physiology of individual roots are needed (Rewald et al., 2012). Root length can be the most important characteristics because many researchers believe that the root length per unit volume of soil is the best feature to calculate water uptake by the plant (White and Kirkegaard, 2010). The root diameter reduces in salt stress conditions. It varies in different species (Eshel and Beeckman, 2013). Grouping of accessions by multivariate methods in would be of practical value to wheat breeders in that representative accessions may be chosen from different clusters for breeding purpose and it also helps to define strategies for further collection of germ plasm (Alavi siney et al., 2013). The objectives of this study were to evaluate effect of NaCl salinity on seedling root traits in doubled haploid barley, grouping, ranking and selecting of superior genotypes based on studied traits. Materials and methods: In order to investigate the effect of NaCl salinity on seedling root traits in doubled haploid barley, a study was carried out as a factorial experiment based on completely randomized design with three replications in the green house of Zanjan University in 2012. Fifty doubled haploid lines were studied in zero (control) and 150 mM salinity levels. Traits of the root area, root angle, cumulative root length, length of the longest root, diameter root were measured with daily imaging of the seedling. Data were analyzed by the analysis of variance (ANOVA) with using SPSS (21). Cluster analysis and Aronachalam and Bandyopadhyay(1984) were used for grouping and ranking the doubled haploid lines respectively. Results and Discussion The results of the variance analysis showed significant differences between lines and interaction of line × salinity for all of traits. The significant differences among lines for the studied traits refer to the presence of considerable variation among lines and give a chance to plant breeders for betterment of these characters through breeding. The significant interaction between lines and Salinity shows a lines specific adaptation to different salinity. Therefore, this diversity can successfully be used for improvement of barley yield. However, the correct selection of doubled haploid lines can be considered as one of the crucial factors in farm management and economic barley production. Generally, salinity was decreased root length and cumulative root length. In four lines did not decrease the root length under salt stress and in three lines didn’t show reduced cumulative root length under salt stress. The root angle, in all lines except the six lines, under Stress-free conditions was greater than the stress condition. Root area showed a downtrend in stress conditions than under normal condition those five lines are not obeyed of the law. The effect of salinity on root diameter did not show similar results among the lines. Using cluster analysis and Arunachalam and Bandyopadhyay (1984) method, barley doubled haploid lines were divided two groups based on studied traits both normal and salinity conditions. Genotypes with 2, 29 and 69 code were selected as superior genotypes in both of conditions. Conclusion The results of experiment showed that the root traits are affected by salt stress. Since, it is necessary, we know about the relationship between root traits such as, area and length of root and their relationship with salt stress. Salt stress decreased amount of root area, cumulative length, length of longest root and root angle. Tolerance to salinity is related to all of traits involved in salt tolerance. The root absorbs water and nutrients to the extensive role that it can play a major role in salinity tolerance. Cluster analysis based on the studied traits in both conditions (normal and stress) divided genotypes in two groups and multivariate analysis of variance confirmed these results. Arunachalam and Bandyopadhyay showed genotypes number 2, 29 and 62 were superior genotypes in both conditions. Therefore, these genotypes can be used in both of condition.
Hasan Nouriyani
Abstract
Introduction Hormones are the most important crop plant growth regulators in response to genetic and environmental conditions. Paclobutrazol (PBZ) is a triazole plant growth regulators of the categories used in the early 1980s. According to some researchers, paclobutrazol reduced plant height (Yang et ...
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Introduction Hormones are the most important crop plant growth regulators in response to genetic and environmental conditions. Paclobutrazol (PBZ) is a triazole plant growth regulators of the categories used in the early 1980s. According to some researchers, paclobutrazol reduced plant height (Yang et al., 2001), increasing the number of tillers per plant and increasing the number of grains per spike (Bayat et al., 2010), increased tolerance to environmental stresses and non-environmental (Berova et al., 2002). Heat stress is one of the major limiting factors of environmental in wheat production and wheat germ stage is the most sensitive periods of high temperatures (Pradhan et al., 2012). The aim of this study was to evaluate the physiological characteristics of wheat grain growth and yield than using different concentrations of paclobutrazol foliar application is in optimal conditions and heat stress. Materials and Methods This study in two independent experiments were conducted each split plot in a randomized complete block design with four replications carried out in Dezful area, Iran in 2013-2014. The first experiments on the cultivation of crop varieties recommended (November) and in order to phenological stages of plant growth to coincide with heat stress after pollination season, planting dates in other experiments the first was in February. In each experiment, four levels of paclobutrazol (0, 50, 100 and 150 mg per liter) at the beginning of stem elongation sprayed on to Shoot applied, As main plots and three cultivars of wheat (Star, Vee/Nac and Chamran) were considered as sub plots. Results and Discussion The results showed that in both optimum conditions and heat stress season, consumption growth regulator paclobutrazol significantly increased the effective grain filling period, 1000-grain weight and grain yield, but the effect of this treatment on the grain growth rate was not significant. Results of stepwise regression analysis showed that the duration of grain filling was the most important attribute of variations grain weight (R2=0.59) and then grain growth rate much of the rest of the changes are determined. Conclusions The yield of the late Star because of the late Star pollination and subsequent exposure to heat stress than in the final stages of the early Vee/Nac and middle Chamran, the gradient of the effective grain filling period, grain weight and higher grain yield under heat stress end of the season was compared to optimum conditions. Overall results showed that the effect of growth regulator paclobutrazol on characteristics of grain growth and yield were positive, therefore can be with the proper use from the damage resulted from heat stress, especially at critical stages of plant growth can be prevented.
Akhtar Auobi; Fatemeh Rahmani
Abstract
Introduction Plants continuously face several environmental and stressing factors. Among these factors, salinity, drought are the major environmental stimuli that can greatly influence plant growth and productivity. Plant water relations are disturbed by drought or high salinity due to the lowered water ...
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Introduction Plants continuously face several environmental and stressing factors. Among these factors, salinity, drought are the major environmental stimuli that can greatly influence plant growth and productivity. Plant water relations are disturbed by drought or high salinity due to the lowered water potential in the environment hampering water uptake or favouring loss of water from plants. These stresses impose osmotic stress on plants, causing a series of morphological, physiological, biochemical and molecular changes in plants. To survive these stresses, plants have evolved complex mechanisms to perceive external signals and to manifest adaptive responses with proper physiological, morphological and molecular changes (Zhu, 2002). In addition to, Closing of stomata reduces transpirational losses of water from leaves. The uptake and the biosynthesis of compatible solutes and the regulation of membrane permeability and transport are further measures that either hold back water within the plant or facilitate further uptake of water (Zhu, 2001; Sharp et al., 2004). AQPs are present in the tonoplast, the plasma membrane, and possibly in other internal membranes. In addition to water, individual MIP members may mediate the movement of small non-charged molecules, for example glycerol,urea, CO2, or formaldehyde(Tyerman et al., 2002; Gaspar et al., 2003; Uehlein et al., 2003). Furthermore, a role as osmotic or turgor sensors has been suggested for MIPs (Hill et al., 2004). Materials and methods Seeds of maize (Zea mays L. cv. SC. 704) were obtained from Urmia Agriculture Research Centre. Seeds were graded and the big uniform shaped ones selected. Seeds were surface sterilized with 2% sodium hypochlorite for 10 min then washed with sterile distilled water three times. Following vernalization, seeds were placed in growth chamber and transferred to the plastic pot containing a soil mixture of sand (30%) and compost (70%). Plant experienced the following growth conditions for 21 days: the light regime of 16/8 h light/dark with 80% humidity and 22°C temperature. After 21 days of culture, began treatment plants, were applied For short (4 days) and long (8 days) period treatment for three salinity stress NaCl(200mM), CaCl2(40mM) and drought PEG6000(10%). 21 day-old-maize plants were divided into 8 groups and undergone following treatment for wounding and 4 and 8 days. Results and discussion The RT-PCR result of all stressed leaves indicated no significant difference in PEG6000(10%) treatment in comparison to the others treatment. ZmPIP1,2 expression had been increased in NaCl-4 , NaCl-8, CaCl2-4 and especially CaCl2-8 plants compared to control plants. This indication showed the effect of salinity stresses (NaCl and CaCl2) on the ZmPIP1,2 suppression. Semi-quantitative RT-PCR analysis of ZmPIP1,5 gene expression showed significant reduction in NaCl-8 plants while undergoing treatment of plants with CaCl2-4, PEG-4 and PEG-8 increase in gene expression observed. Other treated plants did not show significant changes in gene expression. Our results propose these genes are necessary for efficient sensing of environmental changes. Plasma membrane intrinsic proteins belonging to the aquaporin family have been reported to function in water transport in many plant species (Katsuhara et al., 2002; Chaumont et al., 2001; Tester and Bacic, 2005). Conclusions From the results of this experiment, it can be concluded that Semi-quantitative RT-PCR analysis of ZmPIPs genes expression in maize showed differential response and significant down or up regulation under applied adverse conditions. Further studies must be carried out to investigate the mechanism by which plant gene expression is controlled by abiotic stresses.
Hamid Sodaiizadeh; Maryam Shamsaie; Mahdieh Tajamoliyan; Seyed Ali Mohammad Mirmohammady Maibody; Mohammad Ali Hakimzadeh
Abstract
Introduction Water is the most basic ecological factors in arid and semiarid environments which determine the rate of plant growth and development. Therefore, the effective use of water resources for optimum growth should always be considered. Abiotic environmental stresses such as drought stress are ...
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Introduction Water is the most basic ecological factors in arid and semiarid environments which determine the rate of plant growth and development. Therefore, the effective use of water resources for optimum growth should always be considered. Abiotic environmental stresses such as drought stress are the most important problems in these areas that have a negative impact on growth and development of the plants. Water stress, permanently or temporarily, is the most limitative environmental factors in the development and distribution of natural vegetation. Drought stress occurs in plants when the received water is less than the casualties. Given the importance of medicinal plants, especially in the pharmaceutical industry, and deficiencies in various aspects of agricultural nature of this plant is very important. Given the importance of medicinal plants, especially in the pharmaceutical industry and their rarity in the nature, investigating on various aspects of these types of plants is recommended. Diversity and abundance of the plants in different parts of the earth, more than any other environmental factor, depends on the amount of water available to the plants. Drought stress is the most important abiotic plays an important role in reducing the production of the plants’ crops in the world. Materials and methods In order to determine the evaluate the effects ofdifferent levels of drought stress on some physiological characteristics of Thymus fedtschenkoi a complete randomized block design is carried out in the greenhouse of the University of Yazd in 2014. For seeding cultivation,the pots with a height of 21 cm and the diameter of 20 cm including drains are used. In order to reduce the heat exchange between the soil inside and the outside surface, the pots are isolated perfectly.Using some gravel at the bottom of the pots and placing some dishes under them to egress the extra water was recommended in order to improve drainage. To fill the pots, a mixture of the sandy soil and leaf soil was used.The treatment of drought stress includes 100, 75, 50 and 25% of field capacity (fc)for which the number of four replication are applied. Results and discussion The results showed that chlorophyll a and total chlorophyll contents were affected by water deficit at 1% level of probability where chlorophyll b, proline contents and relative water content (RWC) significantly were affected at 5% level of probability. The results also showed that water stress had not a significant effect on soluble sugars content. Drought stress significantly affected the amount of prolines, so that, minimum amount of this factor was observed in 100% Field capacity (FC). Maximum a, b and total chlorophyll contents of Thymus fedtschenko (by 0.48, 0.167 and 0.633 mg/g, respectively) were obtained, at 25% of field capacity whereas the minimum amounts of these factor were obtained at 100% of field capacity. Overall, results indicate that increasing of prolin accumulation as well as chlorophyll contents are primary strategies of Thymus fedtschenkoagainst drought stress. The maximum level of proline is related to the Thymus fedtschenko of 25%, 50% and 75%. However, the minimum quantity is observed in the Thymus fedtschenko of 100%.
Volume 9, Issue 4 , January 2017, Pages 428-428
