College of Agriculture, Bahauddin Zakariya University, Bahadur Sub-Campus Layyah, Layyah, Pakistan.
Department of Agronomy, Bahauddin Zakariya University, Multan, Pakistan.
Sci Rep. 2021 Nov 30;11(1):23170. doi: 10.1038/s41598-021-02594-4.
Due to climate change, temperature in late February and early March raised up which cause heat stress at reproductive stage (terminal growth phase of wheat crop) which has become the major causative factor towards low wheat production in arid and semiarid regions. Therefore; strategies need to be adopted for improving terminal heat stress tolerance in wheat. In this study, we assessed whether foliar application of silicon (Si) (2 and 4 mM) at terminal growth phase i.e. heading stage of wheat imposed to heat stress (37 ± 2 °C) under polythene tunnel could improve the performance of wheat. Results of the study revealed that heat stress significantly reduced the photosynthetic pigments (chlorophyll a, b and a + b and carotenoids) leading to a lower grain yield. However, a 4 mM Si application (foliar applied) at heading stage prominently increased the chlorophyll a, b and a + b and carotenoids of flag leaf by improving the activities of enzymatic antioxidants (catalase, peroxidase and superoxide dismutase) and osmoprotectants (soluble sugar protein and proline) under terminal heat stress. Improvements in the performance of wheat (chlorophyll contents, carotenoids, soluble sugar and proteins and proline and yield) with foliar application of Si were also observed under control conditions. Correlation analysis revealed strong association (r > 0.90) of chlorophyll contents and carotenoids with grain and biological yield. Negative correlation (-0.81 < r > -0.63) of physio-biochemical components (antioxidants, proline, soluble sugars and proteins) with yield revealed that under heat stress these components produced in more quantities to alleviate the effects of heat, and Si application also improved these physio biochemical components. In crux, foliar application of Si alleviates the losses in the performance of wheat caused by terminal heat stress by improving the antioxidant mechanism and production of osmoprotectants.
由于气候变化，二月下旬和三月初的气温升高，导致生殖期（小麦作物的终末生长阶段）出现热应激，这已成为干旱和半干旱地区小麦产量低的主要原因。因此；需要采取策略来提高小麦对终末热应激的耐受性。在这项研究中，我们评估了在聚乙烯隧道中的终末生长阶段（小麦抽穗期）叶面喷施硅（Si）（2 和 4 mM）是否可以改善小麦的性能。研究结果表明，热应激显著降低了光合色素（叶绿素 a、b 和 a+b 和类胡萝卜素），导致籽粒产量降低。然而，在抽穗期叶面喷施 4 mM Si （叶面喷施）显著增加了旗叶的叶绿素 a、b 和 a+b 和类胡萝卜素，通过提高酶抗氧化剂（过氧化氢酶、过氧化物酶和超氧化物歧化酶）和渗透调节剂（可溶性糖蛋白和脯氨酸）的活性，提高了终末热应激下的活力。在对照条件下，叶面喷施 Si 也改善了小麦的性能（叶绿素含量、类胡萝卜素、可溶性糖和蛋白质以及脯氨酸和产量）。叶面喷施 Si 与叶绿素含量和类胡萝卜素与粒重和生物产量之间存在很强的相关性（r>0.90）。生理生化成分（抗氧化剂、脯氨酸、可溶性糖和蛋白质）与产量之间的负相关（-0.81
