Mojdeh Sadat Khayat Moghadam; Ahmad Gholami; Amir Hossein Shirani rad; Mahdi BaradaranFiroozabadi; Hamid Abbasdokht
Abstract
In order to study the effects of late-season drought stress and foliar application of potassium silicate on yield and yield components of spring genotypes of canola, a factorial split-plot experiment is conducted in Karaj, Iran in a randomized complete block configuration with three replications for ...
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In order to study the effects of late-season drought stress and foliar application of potassium silicate on yield and yield components of spring genotypes of canola, a factorial split-plot experiment is conducted in Karaj, Iran in a randomized complete block configuration with three replications for two years of cultivation (2016-2018). The irrigation is performed at two levels in this study, including routine irrigation (control) and interruption of irrigation from the pod formation stage. Potassium silicate foliar application at two levels is comprised of 0 and 4 g liter-1 in factorial status in main plots and five Brassica napus L. genotypes including OG×AL, RGS×SLM, DALGAN, RGS003 and RGS×Okapi in subplots. The results show that the measured properties are affected by the applied treatments. Full irrigation with foliar application in OG×AL genotype results in highest seed yield (5620 Kg/ha) and total chlorophyll content (1.71 mg/g.FW) increase stomatal resistance, leaf proline, leaf soluble and carbohydrates, decreasing total chlorophyll content and relative leaf water content. Under drought stress conditions, DALGAN and RGS× SLM genotypes have higher yield, which indicates its better performance under stress conditions. Finally, our research demonstrates Potassium Silicate's beneficial effects in improving the drought tolerance of canola plants, particularly at the end of the season. Our study will act as a foundation for any attempt in new approaches to mitigate drought damage, establishing a functional connection between the position of potassium silicate, physiological response, and drought stress tolerance in canola plants.
Sodabeh Reza Beighi; Ehsan Bijanzadeh
Abstract
In order to study the effect of silicon on biochemical traits, leaf relative water content and yield of two bread and durum wheat cultivars under late season water stress conditions, a split factorial experiment in a randomized complete block design was conducted in three replicates during 2017-2018 ...
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In order to study the effect of silicon on biochemical traits, leaf relative water content and yield of two bread and durum wheat cultivars under late season water stress conditions, a split factorial experiment in a randomized complete block design was conducted in three replicates during 2017-2018 growing season. Treatments included of water stress in two levels included normal irrigation and water stress at the end of flowering, silicon (Si) spraying at 0, 1, 2, and 3 mM and two wheat cultivars consisted of Chamran as bread wheat and Shabrang as durum wheat. The results showed that the main effects of late seasonal water stress, cultivar and silicon on leaf relative water content (RWC), total chlorophyll, carotenoid content and yield were significant. Under water stress conditions, when plants exposed to 3 mM silicon RWC increased 50% compared to no silicon application conditions. Grain protein under water stress conditions and 3 mM silicon was 59.3% higher than no silicon condition. Also, total chlorophyll content and carotenoid content under water stress conditions and application of 3 mM silicon increased 42.5 and 44.9%, respectively. In Chamran cultivar, application of silicon at 3 mM increased total chlorophyll content, carotenoid content, RWC and grain protein 40, 43, 42 and 56.4%, respectively, which caused 19.7% increase in grain yield compared to Shabrang cultivar under water stress conditions. In general, foliar application of 3 mM silicon by improving total chlorophyll content, carotenoid content and RWC can play an important role in increasing yield under water stress conditions.
Zeinab Rafie-rad; Ahmad Golchin; Yahya Tajvar; Javad Fatahi-moghadam
Abstract
Considering the limited water resources in Iran, utilization of modern methods of water conservation and preservation, such as the application of superabsorbent polymers in the soil, is one of the confront approaches of water deficit. For this purpose, in order to investigate the effect of superabsorbent ...
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Considering the limited water resources in Iran, utilization of modern methods of water conservation and preservation, such as the application of superabsorbent polymers in the soil, is one of the confront approaches of water deficit. For this purpose, in order to investigate the effect of superabsorbent on vegetative and reproductive growth of Page Mandarin in drought stress condition, a factorial experiment bases on the completely randomized design with three replications was conducted in 2016 at the Citrus and Subtropical Fruits Research Center of Ramsar. Factors were consisted of three levels of water stress (100, 75 and 50% of field capacity) and superabsorbent (0, 0.25 and 0.5% wt). The results showed that by increasing of water stress, amounts of electrolyte leakage, proline, fruit cracking and titratable acidity were increased. As well as 50% of field capacity level, 0.5% superabsorbent application was caused significantly increase leaf relative water content, total chlorophyll content, leaf water potential 60%, 15%, 23% and 87.5% and decrease electrolyte leakage and total soluble solids 65% and 22% respectively, compared with condition of treatment without applying superabsorbent. So, it seems that superabsorbent can increase the plant tolerance in counteracting moisture stress by maintaining unusable water.
Ali Tadayyon; Hajar Nadeali
Abstract
To evaluate the effect of drought stress on the physiological characteristics of salad burent (Poterium sanguisorba), a field experiment was conducted in split-plot based on randomized complete block design with three replications during 2010 growing season. Four levels of irrigation (20, 40, 60 and ...
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To evaluate the effect of drought stress on the physiological characteristics of salad burent (Poterium sanguisorba), a field experiment was conducted in split-plot based on randomized complete block design with three replications during 2010 growing season. Four levels of irrigation (20, 40, 60 and 80 percentage of available soil moisture) and three different ecotypes of Tehran, Semirom and Fereidon Shahr were used as main and sub plots, respectively at the three harvest stages (82, 112 and 142 days after planting).Water stress significantly affected on the shoot dry weight, leaf relative water content, protein (%), total chlorophyll and chlorophyll a and b, but effect of the ecotypes was only significant on shoot dry weight at all three stages and relative water content at second and third stages. Maximum shoot dry weight obtained in Tehran ecotype under 20 and 40% of available water at each three harvest stage. More relative water content was observed at 40% of available water at each harvest stage.