水分胁迫对黔金荞麦1号生理特性的影响

摘要

In order to explore the drought resistance mechanism and accelerate the utilization and extension of bred variety,Using F.dibotrys CV.Qianjin No.1 as experimental materials,the cell injury rate,MDA content,proline content,soluble sugar content,SOD activity,POD activity and CAT activity were investigated under water stress in pool cultivation.The results showed that there was no significant change in all of indexes.With the prolongation of treatment time,the injury rate,MDA content,soluble sugar(SS),the activities of peroxidase(POD)and catalase(CAT)increased.The proline content (Pro), superoxide dismutase(SOD)and water use efficiency increased in the beginning and decreased at last.The net photosynthetic rate,stomatal conductance and transpiration rate decreased.Based on the results, F.dibotrys CV.Qianjin No.1 could endure and adapt to the low-grade and middle-grade water stress through increasing the content of osmotic substances and coordinating the activity of protective enzymes. Under high-grade water stress,the ability of osmotic adjustment and the activity of protective enzymes weakened,the cell membrane injured seriously,the photosynthetic capacity decreased.%为探索黔金荞麦1号（Fagopyrum dibotrys CV．Qianjin No．1）对水分胁迫的适应机制，加快金荞麦育成品种的推广利用，以黔金荞麦1号为试验材料，采用室内盆栽模拟水分胁迫，测定分析了水分胁迫下育成品种主要生理指标的变化情况。结果表明：正常水分条件下，各指标无显著变化。处理组黔金荞麦1号的电导率、丙二醛（MDA）和可溶性糖（SS）含量及过氧化物（POD）和过氧化氢（CAT）酶活性随水分胁迫强度的增加而升高，脯氨酸（Pro）含量、超氧化物歧化（SOD）酶活性和水分利用效率随水分胁迫强度的增加呈先升高后降低的趋势，净光合速率、气孔导度和蒸腾速率呈降低趋势。轻、中度水分胁迫时，黔金荞麦1号能够通过调节自身的渗透调节物质含量和保护酶活性来减轻水分胁迫伤害，维持植株的正常生理代谢功能。重度水分胁迫时，渗透调节能力和保护酶活性减弱，细胞膜受伤害程度增强，光合能力降低。