Evaluation of salinity stress on morphophysiological traits of four salin tolarant wheat cultivars

For assessment the effects of salinity on morphophysiological traits of wheat an experiment with four caltivars (Karchia, Sorkh tokhm, Sholeh and Roshan) and one line (1-66-22) in four salt concentrations(0, 60, 120, and 180 mM NaCl), were conducted by factorial analysis in a completely randomized design with three replications. The rate of leaf area were measured in four stages. In booting stage, relative chlorophyll content (SPAD meter), and in pollination phase the rate of Na+ and K+ iones in four leaves(up to down) were assessed and finally stem length and total dry matter were measured. Results showed that salinity reduced leaf area, total dry matter stem length of plants and relative chlorophyll content. With increasing of salinity the rate of Na+ were increased but the rate of K+ iones were decreased. Also the salt exclusion was observed at nodes of stem that of 1-66-22 was spot form

Water stress affect water relations, photosynthesis and oxidative defense mechanism in wheat (Triticum aestivum L.)

Water stress is a major obstacle to agricultural production, significantly impacting both yield and quality. During the 2017–18 crop year in Shahriar region near Tehran, Iran, known for its dry and cold climate, a study was conducted to examine the influence of different irrigation levels on the quantitative and qualitative characteristics of various wheat cultivars. The experiment involved three irrigation levels: normal irrigation (control), withholding irrigation at the flowering stage, and withholding irrigation at the seed-filling stage as primary factors, with 21 different cultivars as secondary factors. The analysis showed that irrigation, cultivar type, and their interactions had a significant effect on grain yield, proline, total chlorophyll, carbohydrate content in the first and second internodes during flowering and ripening, as well as on SOD, CAT, GPX, MDA, DT, and D-OH-dG levels at a one percent significance level. Withholding irrigation at the flowering stage had a more severe impact compared to the seed-filling stage. The Rakhshan and Sivand cultivars yielded the highest and lowest grain yields under normal irrigation conditions, while the drought-tolerant Ofogh cultivar showed lower yields when irrigation was withheld at the flowering stage. Water stress led to increased proline levels and higher levels of SOD, CAT, MDA, DT, and D-OH-dG in wheat cultivars. The Rakhshan and Sivand cultivars were identified as drought-tolerant in this region

Water stress affect water relations, photosynthesis and oxidative defense mechanism in wheat (Triticum aestivum L.)

Water stress is a major obstacle to agricultural production, significantly impacting both yield and quality. During the 2017–18 crop year in Shahriar region near Tehran, Iran, known for its dry and cold climate, a study was conducted to examine the influence of different irrigation levels on the quantitative and qualitative characteristics of various wheat cultivars. The experiment involved three irrigation levels: normal irrigation (control), withholding irrigation at the flowering stage, and withholding irrigation at the seed-filling stage as primary factors, with 21 different cultivars as secondary factors. The analysis showed that irrigation, cultivar type, and their interactions had a significant effect on grain yield, proline, total chlorophyll, carbohydrate content in the first and second internodes during flowering and ripening, as well as on SOD, CAT, GPX, MDA, DT, and D-OH-dG levels at a one percent significance level. Withholding irrigation at the flowering stage had a more severe impact compared to the seed-filling stage. The Rakhshan and Sivand cultivars yielded the highest and lowest grain yields under normal irrigation conditions, while the drought-tolerant Ofogh cultivar showed lower yields when irrigation was withheld at the flowering stage. Water stress led to increased proline levels and higher levels of SOD, CAT, MDA, DT, and D-OH-dG in wheat cultivars. The Rakhshan and Sivand cultivars were identified as drought-tolerant in this region

Effect of drought stress on leaf soluble sugar content, leaf rolling index and relative water content of proso millet (Panicum miliaceum L.) genotypes

With respect to water shortage in arid and semi- arid regions, the study about drought stress effects on crop plants and selection of resistance cultivars, are among the most important goals in the agricultural researches. In order to examine drought stress effects on millet, an experiment was conducted in Birjand and Sarbisheh, simultaneously. In this experiment, five irrigation treatments (well-watered, drought stress in vegetative stage, in ear emergence stage, in seed filling stage and in vegetative and seed filling stage) and five proso millet genotypes (Native, K-C-M.2, K-C-M.4, K-C-M.6 and K-C-M.9) were compared in a split plot design along with three replications. Drought stress increased grain protein content, leaf rolling index and soluble sugars concentration and decreased seed germination and leaf RWC. Although seed protein content and germination percentage of genotypes were not significantly different, there were some differences among leaf rolling index, RWC and soluble sugar content of these genotypes. The results of this study indicated that leaf sugar content, RWC and leaf rolling index can not be considered as the only parameters for selection of high yield genotypes. Therefore, it is recommended that some other factors should also be used apart from the above mentioned ones