Plant Physiology and Biochemistry Section, Department of Botany, Aligarh Muslim University, Aligarh 202 002, India.
Chemosphere. 2011 Nov;85(10):1574-84. doi: 10.1016/j.chemosphere.2011.08.004. Epub 2011 Sep 6.
The objective of this study was to establish relationship between boron induced oxidative stress and antioxidant system in Vigna radiata plants and also to investigate whether brassinosteroids will enhance the level of antioxidant system that could confer tolerance to the plants from the boron induced oxidative stress. The mung bean (V. radiata cv. T-44) plants were administered with 0.50, 1.0 and 2.0 mM boron at 6 d stage for 7 d along with nutrient solution. At 13 d stage, the seedlings were sprayed with deionized water (control) or 10(-8) M of 28-homobrassinolide and plants were harvested at 21 d stage to assess growth, leaf gas-exchange traits and biochemical parameters. The boron treatments diminished growth, water relations and photosynthetic attributes along with nitrate reductase and carbonic anhydrase activity in the concentration dependent manner whereas, it enhanced lipid peroxidation, electrolyte leakage, accumulation of H(2)O(2) as well as proline, and various antioxidant enzymes in the leaves of mung bean which were more pronounced at higher concentrations of boron. However, the follow-up application of 28-homobrassinolide to the boron stressed plants improved growth, water relations and photosynthesis and further enhanced the various antioxidant enzymes viz. catalase, peroxidase and superoxide dismutase and content of proline. The elevated level of antioxidant enzymes as well as proline could have conferred tolerance to the B-stressed plants resulting in improved growth, water relations and photosynthetic attributes.
本研究的目的是建立硼诱导的氧化应激与豇豆植物抗氧化系统之间的关系，并研究油菜素内酯是否会增强抗氧化系统的水平，从而使植物耐受硼诱导的氧化应激。在 6 天龄时，将绿豆（V. radiata cv. T-44）植株用 0.50、1.0 和 2.0 mM 硼处理 7 天，并与营养液一起处理。在 13 天龄时，用去离子水（对照）或 10(-8) M 的 28-高油菜素内酯喷洒幼苗，在 21 天龄时收获植物，以评估生长、叶片气体交换特性和生化参数。硼处理以浓度依赖的方式降低了生长、水分关系和光合作用以及硝酸还原酶和碳酸酐酶活性，而在叶片中增强了脂质过氧化、电解质渗漏、H(2)O(2)和脯氨酸的积累以及各种抗氧化酶，在较高浓度的硼下更为明显。然而，将 28-高油菜素内酯后续应用于硼胁迫植物，改善了生长、水分关系和光合作用，并进一步增强了各种抗氧化酶，如过氧化氢酶、过氧化物酶和超氧化物歧化酶以及脯氨酸的含量。抗氧化酶和脯氨酸水平的升高可能使 B 胁迫植物具有耐受性，从而改善生长、水分关系和光合作用特性。
