Ali Reza Sobhani; Hasan Hamidi
Abstract
In order to study the effect of water deficit and potassium fertilizer on the yield and water use efficiency (economic and biologic) a split block experiment based on RCBD was conducted with three replications using line-source sprinkler irrigation in Khorasan Razavi Agricultural and Natural Resources ...
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In order to study the effect of water deficit and potassium fertilizer on the yield and water use efficiency (economic and biologic) a split block experiment based on RCBD was conducted with three replications using line-source sprinkler irrigation in Khorasan Razavi Agricultural and Natural Resources Research Center. Potassium levels including 0, 90, 180, and 270 kg K2O ha-1 were considered as main plots. Water deficit levels including 0.75m (control), 3.75m (very light), 6.75m (light), 9.75m (severe deficit), and 12.75m (very severe deficit) from the line source were considered as sub plots. These factors were investigated in a special line-source statistical design with three replications (in right and left of line-source), so that the right or left direction of the line source was assigned as the sub-sub plots. Results showed increased tuber yield and biological yield of potato through application of potassium, whereas increasing the distance from the line source decreased these traits. Under very severe stress conditions (12.75m from the line source), the tuber yield was 80% and 62.67% lower than the control at the first and second year of the study, respectively. The highest economical water use efficiency (EWUE), biological water use efficiency (BWUE) and tuber yield resulted from 270 kg K2O ha-1. Interaction effects of potassium and water amounts on yield, EWUE and BWUE were significant in the second year. The greatest yield was obtained from 270 kg K2O ha-1 and control treatment (sufficient water) and the highest BWUE was observed using 270 kg K2O ha-1 and severe deficit.
Mostafa Heidari; Vahid Karami
Abstract
To evaluate the effects of water stress and two kinds of mycorhiza species on grain yield, yield components, chlorophyll content, chlorophyll fluorescence, proline and carbohydrate concentration in sunflower (Helliantus annus Var. Alster), a field experimental as a split plot design was conducted with ...
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To evaluate the effects of water stress and two kinds of mycorhiza species on grain yield, yield components, chlorophyll content, chlorophyll fluorescence, proline and carbohydrate concentration in sunflower (Helliantus annus Var. Alster), a field experimental as a split plot design was conducted with three replications in 2011 at the Research Farm of the University of Zabol. Water stress treatments included 90 (control), 70 and 50 percent of the field capacity as the main plot and two different mycorrhiza species, including Glumus mossea and Glumus etanicatum and also a control or without any inoculation as sub plots. Results showed that water stress significantly decreased grain yield, biological yield and harvest index. The grain yield reduction was about 15.07% at the highest level of water stress in comparison with the control. However application of mycorhiza increased grain yield, biological yield and harvest index, but it had not significant effects on them. Water stress increased soluble carbohydrate and proline content in leaves, whereas significantly reduced head weight, head diameter, grains per head No. and 1000-seed weight. Using strains of mycorhiza in this study only had significant effects on proline content, head diameter, grains per head No. and 1000-seed weight. Interaction between water stress and strains of mycorhiza had only an impact on head weight and number of grains per head. So that, at the highest levels of water stress, the application of Glumus mosseahad hadthe highest influence on sunflower yield and yield components.
Najmeh Moghimi; Yahya Emam
Abstract
In order to evaluate the effect of water stress and nitrogen levels on yield and morpho-physiological traits of two forage sorghum cultivars, a field experiment was conducted at the College of Agriculture, Shiraz University, during spring and summer 2011. The experiment was carried out as a split-split ...
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In order to evaluate the effect of water stress and nitrogen levels on yield and morpho-physiological traits of two forage sorghum cultivars, a field experiment was conducted at the College of Agriculture, Shiraz University, during spring and summer 2011. The experiment was carried out as a split-split plot design based on RCBD with 3 replications. 100, 75 and 50% FC were considered as main plots, whereas nitrogen levels (150, 300 and 450 kg urea.ha-1) and forage cultivars (Pegah and KFS2) were considered as sub- and sub-sub plots. Results showed that water stress significantly reduced crop growth rate (CGR) and leaf area index (LAI) over the growing season, while decreased forage dry weight and yield at harvest time. Nitrogen fertilizer application significantly enhanced the above traits. Two sorghum cultivars showed significant differences in terms of morphological characters and some measured traits. So that Pegah cultivar was found superior as far as CGR, forage dry weight and forage yield were concerned, while, KFS2 cultivar showed higher LAI. Results also indicated that increasing soil moisture and nitrogen levels can have considerable effect on forage yield improvement. In general, Pegah cultivar and the interaction of 300 kg urea per ha. and 100% FC, achieved the greatest forage yield and could be recommended as the best treatment for similar agro-climatic conditions.
Nahid Davoody; Mohammad Javad Seghatoleslami; S. Gholam Reza Mousavi; Ali Azari Nasrabad
Abstract
In order to study the effect of nano- zinc oxide and drought stress on yield, yield components and water use efficiency (WUE) of foxtail millet, a split-plot experiment was done based on RCBD with three replications in 2012 at Research Farm of Islamic Azad University, Birjand branch. Irrigation treatments ...
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In order to study the effect of nano- zinc oxide and drought stress on yield, yield components and water use efficiency (WUE) of foxtail millet, a split-plot experiment was done based on RCBD with three replications in 2012 at Research Farm of Islamic Azad University, Birjand branch. Irrigation treatments including optimal irrigation (%100 of plant water-requirement) and drought stress (%50 plant water-requirement) were considered as main-plots. Zinc foliar application treatment as ZnO with concentration of (3000, 6000 and 12000 ppm) and nano ZnO (250, 500 and 1000 ppm) were considered as sub-plots. Results showed that drought stress declined panicle number per unit area, seed number per panicle, 1000- seed weight, seed yield, harvest index, and water-use efficiency. The greatest seed yield was achieved using optimal irrigation treatment (%100 water-requirement) and zinc oxide fertilizer with the concentration of 6000 ppm. On the other hand, the effect of zinc oxide foliar application (typical and nano) was non-significant on all studied characteristics.
Majid Abdoli; Mohsen Saeidi; Saeed Jalali-Honarmand; Siroos Mansourifar; Mohammad Eghbal-Ghobadi
Abstract
Evaluation of the physiological and biochemical traits can help to identify strategies for selection of resistant cultivars and increased crop yield production under diverse environmental conditions such as drought stress conditions. To this end, an experiment was laid out in a split–plot arranged ...
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Evaluation of the physiological and biochemical traits can help to identify strategies for selection of resistant cultivars and increased crop yield production under diverse environmental conditions such as drought stress conditions. To this end, an experiment was laid out in a split–plot arranged as a randomized complete blocks design with nine cultivars, two levels of water regimes and three replications during 2010-2011 seasons at the Research Farm of Razi University of Kermanshah. The results showed that post-anthesis water deficit significantly decreased grain yield, biomass and grain weight and had not significant effect on other yield components. In well watered and water deficiency stress, Sivand and DN-11 had the greatest grain yield, respectively. Chamran cultivar showed the lowest grain yield under post-anthesis water deficiency stress. Post-anthesis water deficiency stress significantly decreased leaf soluble proteins concentration, chlorophyll a, b and a/b ratio and greenness index. Despite the reduction of photochemical efficiency of photosystem II, relative water content and stem’s soluble sugar concentration under post-anthesis water deficiency stress, these reductions were not significant.
Mina Hagh Bahari; Raouf Seyed Sharifi
Abstract
In order to investigate the influence of seed inoculation with plant growth promoting rhizobacteria (PGPR) on yield, grain filling rate and period of wheat at different levels of soil salinity, a factorial experiment based on randomized complete block design was conducted with three replications at Research ...
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In order to investigate the influence of seed inoculation with plant growth promoting rhizobacteria (PGPR) on yield, grain filling rate and period of wheat at different levels of soil salinity, a factorial experiment based on randomized complete block design was conducted with three replications at Research Greenhouse of Faculty of Agriculture, University of Mohaghegh Ardabili in 2012. Experimental factors included soil salinity using Nacl at four levels (0, 15, 30 and 60 Mm) and seed inoculation with PGPR at four levels (no inoculation as control, seed inoculation with Azotobacter chroococcum strain 5, Azospirillum lipoferum strain OF, Pseudomonas strain 186). Results showed that increasing soil salinity reduced crop yield, maximum kernel weight and grain filling period, whereas opposite results were observed where seeds were inoculated using PGPR. A two part liner model was used to quantify the grain filling indices. Various levels of salinity and seed inoculation with PGPR significantly affected all grain filling parameters. Comparison of the means showed that the maximum grain weight; grain filling period, yield and yield components were obtained where seeds were inoculated with PGPR under no salinity stress, while minimum of these indices were observed at the highest salinity level and no inoculation. It seems that inoculation of wheat seeds with Azospirillum can be suggested as a promising strategy to increase crop yield and grain filling period under saline conditions.
Mohammad Hossein Saberi; Ashkboos Amini; Ali Reza Samadzadeh; Hamid Tajalli
Abstract
To evaluate the salt tolerance characteristics of 17 newly modified wheat lines, a field experiment was conducted as a randomized complete block design at the Research Farm of Birjand Agricultural Faculty from 2009 to 2011, with the EC of irrigation water and soil saturated paste extract of 8.93 and ...
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To evaluate the salt tolerance characteristics of 17 newly modified wheat lines, a field experiment was conducted as a randomized complete block design at the Research Farm of Birjand Agricultural Faculty from 2009 to 2011, with the EC of irrigation water and soil saturated paste extract of 8.93 and 10.81 dS.m-1, respectively. The treatments included the 17 new wheat lines plus three salt tolerant cultivars (Kavir, Arg, Bam) as check treatments with three replications. The treatments were irrigated with low saline water at early stages of growth (2-3 leaves) to provide a better establishment and then were treated using the high saline water (8.93 dS.m-1) till the end of the crop physiological maturity growth stage. Composite analysis of variance showed that cultivars and lines were significantly different (p<0.01) in regard to days to heading (DHE), days to maturity (DMA), plant height (PLH), peduncle length, seed weight and grain yield. Correlation analysis showed significant positive relations between grain yield and thousand kernel weight (TKW) (r = 0.42*) as well as spike length (r = 0.48*), while there was a negative relationship with DHE. Amongst yield components, grain weight showed a higher role in grain yield (YLD) under salinity stress compared with other traits. Cluster analysis classified the genotypes into three categories (tolerant, moderate and sensitive). Under the imposed salinity situation, analysis showed that the lines 8, 9, 16, 17 had the highest yields of 5.27, 5.22, 5.03 and 5.09 tons per hectare, respectively, which were even greater than the performance of tolerant cultivars. Results of this study highlight that under current situation of the study area, the above selected lines are nominated as salt tolerant lines suitable for wheat mass grain production as well as wheat breeding programs.
Abbas Biabani; Hossein Sabouri; Mousi-Aalreza Vafaie-Tabar
Abstract
This study was carried out as a factorial experiment based on CRD using two native (Gil and Domseiah) and two exotic cultivars (IR58443-6B-10-3 and IR54447-3B-10-2) under three salinity stress levels (0= check and 4, 8 and 12 dSm/m NaCl salinity) at Gonbad Kavoos Agriculture Faculty. Seeds were germinated ...
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This study was carried out as a factorial experiment based on CRD using two native (Gil and Domseiah) and two exotic cultivars (IR58443-6B-10-3 and IR54447-3B-10-2) under three salinity stress levels (0= check and 4, 8 and 12 dSm/m NaCl salinity) at Gonbad Kavoos Agriculture Faculty. Seeds were germinated in laboratory and then cultivated in the pot and evaluated for growth reaction to salinity during vegetative stage, according to instructions of IRRI. The recorded traits were comprised of straw weight, whole panicle weight, total plant weight, flag leaf length and width, height and main panicle length. The salinity, cultivar and interaction effects were significant on all measured traits. Among all cultivars, Domsiah was the only cultivar which showed significant difference with check cultivar in view of total panicle weight. The effect of salinity on both traits of straw weight and total panicle weight showed similar trends.
Nazila Khaef; Fatemeh Enjavie Mosavie; Rafat-Alsadat Alsadat Badihie
Abstract
Calotropis procera L. is a perennial shrub adapted to arid regions which is extensively used for deserting recovery operations. Calotropis procera seed shows low germination under natural conditions.Germination and seedling establishment stages are critical phases for plant survival. In order to examine ...
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Calotropis procera L. is a perennial shrub adapted to arid regions which is extensively used for deserting recovery operations. Calotropis procera seed shows low germination under natural conditions.Germination and seedling establishment stages are critical phases for plant survival. In order to examine the salinity effect on Calotropis procera seed germination, a factorial experiment based on randomized complete block design was conducted with four replications. Salinity factor (NaCl and CaCl2 with the ratio of 5 to 1) had five levels: .0, -0.01, -0.05, -0.1, and -0.15 MPa, which were examined as priming or without priming pretretments. Salinity (NaCl) had significant effects on germination percentage. Increasing salinity decreased germination percentage as well as germination rate and seedling length. Calotropis procera seed germination percentage was 99, 80, 55% in salinity levels of 0, -0.01 and -0.05 MPa, respectively, while it became zero with increasing salinity at -0.1 and -0.15 MPa. Priming with NaCl and CaCl2 (-0.1 MPa) for four days had significant effects (P < 0.01) on the germination percentage. Priming improved the seedling characteristics in all samples, especially in -0.05 Mpa, whereas a reduction was observed in all germination traits with decreasing osmotic potential.
