Mahsa Rafati Alashti; Shahryar Kazemi; Mojdeh Sadat Khayat Moghadam
Abstract
Drought stress is one of the most important factors in reducing yield and seed quality of rapeseed. The present study chiefly tries to evaluate the effect of application of brassinosteroid on seed yield, oil content, oil yield, and fatty acids profile of rapeseed genotypes under late-season water deficit ...
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Drought stress is one of the most important factors in reducing yield and seed quality of rapeseed. The present study chiefly tries to evaluate the effect of application of brassinosteroid on seed yield, oil content, oil yield, and fatty acids profile of rapeseed genotypes under late-season water deficit stresseen considered. A factorial split-plot test has been conducted in a randomized complete blocks design for two cultivation years (2017-2019) in Karaj, Iran. Experimental treatments include two levels of brassinosteroid (i.e., 0 (control) and 0.1μmol) and two levels of irrigation (full irrigation (control) and withholding irrigation from flowering stage) as factorial in the main plots, and rapeseed genotypes (Nafis, Ahmadi, Okapi, Nima, and Niloufar) as subplots. The levels of oleic acid and linoleic acid in the conditions of application of brassinosteroids have been 0.7% and 11% in full irrigation conditions and 1.1% and 6.4% in withholding irrigation conditions, respectively, compared to the control on the other hand, the use of brassinosteroids in withholding irrigation conditions reduce palmitic acid by 14% compared to the control. Okapi genotype has had the highest and lowest erucic acid and grain yield in irrigation conditions, respectively. Under drought stress conditions, the highest seed yield (3112.3 kg/ha) and the lowest amount of erucic acid (0.26%) belonged to Niloufar genotype. The use of brassinosteroids in both irrigation treatments improve the quality of fatty acids and Niloufar cultivar is recommended in both irrigation conditions
Ghorban Khodabin; Mojdeh Sadat Khayat Moghadam; Shahryar kazemi; mahsa rafati alashti
Abstract
This study investigates the effects of different tillage systems (no-tillage, minimum and conventional), fertilizers (no fertilizer, vermicompost (V), urea (U) and combined urea and vermicompost (VU) and irrigation regimes on various quantitative and qualitative traits of rapeseed, as well as soil nitrate ...
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This study investigates the effects of different tillage systems (no-tillage, minimum and conventional), fertilizers (no fertilizer, vermicompost (V), urea (U) and combined urea and vermicompost (VU) and irrigation regimes on various quantitative and qualitative traits of rapeseed, as well as soil nitrate leaching (NL). Field trials have been conducted between 2017 and 2019 in the Research Institute of Forests and Rangelands with no significant difference observed for seed and oil yield between the minimum and conventional till systems. However, the no-till system vs. minimum and conventional till decrease these traits by 22% and 21.5%. The combined application of vermicompost and urea under optimal irrigation conditions boosts oil yield by 24%, compared to the control) of rapeseed. Furthermore, across all tillage types, the highest NL is observed where urea was applied. When compared with urea, V and UV treatments decrease the NL by 67% and 50% in no-till plots, 50% and 36% in minimum till plots, and 49% and 34% in conventional till plots, respectively. Deficit irrigation also reduces linoleic acid by 7.6%. In addition, the highest levels of oleic acid (63.9%) and linoleic acid (20.7%) are observed under residual tillage system with combined fertilizer application and the residual tillage system with vermicompost application, respectively The findings indicate that minimum till in combination with VU treatments supports reduced NL over conventional till and urea fertilization practices, while improving rapeseed quantitative and qualitative traits.
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.