2,4-表芸苔素内酯浸种对干旱胁迫下大麦种子萌发及幼苗生理特性的影响

【目的】研究不同浓度芸苔素内酯溶液对干旱胁迫下大麦种子萌发及幼苗生长的影响，分析芸苔素内酯溶液的最佳浸种浓度。【方法】以新啤6号大麦种子为材料，采用不同浓度(0、5、25、50、100、200μg/L)芸苔素内酯溶液浸种后，在蒸馏水(CK)或23%聚乙二醇溶液中进行纸上发芽试验。统计发芽率、发芽势、发芽指数以及根和芽的干、鲜重，测定分析不同浓度芸苔素内酯溶液浸种对干旱胁迫下大麦芽和根中相对含水量、电导率、丙二醛、脯氨酸、可溶性糖含量以及抗氧化酶活性的影响。【结果】干旱胁迫显著抑制大麦种子的萌发和幼苗生长。与仅干旱胁迫处理相比，5、25μg/L芸苔素内酯溶液处理可使大麦种子发芽率、发芽势和发芽指数分别提高34.23%、65.74%、25.80%和45.45%、31.82%、47.70%。与仅干旱胁迫相比，25μg/L芸苔素内酯处理使根和芽中的可溶性糖含量分别增加7.86%和12.53%,使根和芽中的游离脯氨酸含量分别增加35.06%和20.63%。25μg/L芸苔素内酯处理可使根和芽中的过氧化氢酶、过氧化物酶以及超氧化物歧化酶活性均有所提高。【结论】适宜浓度的芸苔素内酯溶液浸种可提高干旱...

Effects of 2, 4-Epbrassinolide Soaking on Seed Germination and Physiological Characteristics of Barley Seedlings under Drought Stress

【Objective】 In order to study the effects of different concentrations of brassinolide solution on seed germination and seedling growth of barley under drought stress, the optimal concentration of brassinolide solution was determined. 【Methods】 The seeds of Xinpi No.6 barley were soaked in brassinolide of different concentrations (0, 5, 25, 50, 100, 200 μg/L).The paper germination test was carried out in either distilled water (CK) or 23% polyethylene glycol solution.The germination rate, germination potential, germination index and dry and fresh weight of roots and buds were calculated.The effects of brassinolide solution with different concentrations on relative water content, electrical conductivity, contents of malondialdehyde, proline, soluble sugar and antioxidant enzyme activities in buds and roots of barley under drought stress were determined. 【Result】 Drought stress significantly inhibited barley seed germination and seedling growth. Compared with drought stress alone, 5, 25 μg/L brassinolide treatment increased the germination rate, germination potential and germination index of barley seeds by 34.23%, 65.74%, 25.80%, 45.45%, 31.82% and 47.70%, respectively. Compared with drought stress alone, 25μg/L brassinolide treatment increased the soluble sugar content in root and bud by 7.86% and 12.53%, respectively, and the free proline content in root and bud by 35.06% and 20.63%, respectively. Meanwhile, 25 μg/L brassinolide treatment increased the activities of catalase, peroxidase and superoxide dismutase in root and bud. 【Conclusion】 Suitable concentration of brassinolide could increase the content of osmomodulators and antioxidant enzyme activities in barley root and bud under drought stress, promote barley seed germination and seedling growth, and the effect of 25μg/L brassinolide treatment was the most obvious.