干旱胁迫对不同磷效率基因型大豆膜脂过氧化作用的影响

Effect of Drought Stress on Lipid Peroxidation in Soybean Varieties with Different P Efficiency

以不同磷效率基因型大豆黑河27、黑河29为材料,在控制磷素供应水平的条件下,通过控制灌水量的盆栽试验,研究了干旱胁迫对不同磷效率基因型大豆膜脂过氧化作用的影响。结果表明:随土壤干旱强度增加,磷高效基因型大豆叶片丙二醛(MDA)含量、细胞膜透性和O2.-含量递增的幅度明显小于磷低效基因型,超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性及过氧化物酶(POD)活性降低的幅度显著小于磷低效基因型,渗透调节物质可溶性糖(SS)、脯氨酸(Pro)随干旱胁迫强度增大而增加,磷高效基因型大豆的渗透调节能力要明显大于磷低效基因型。表明大豆耐旱性与其抗氧化酶活性相关,渗透调节物质是构成其耐旱性的重要物质基础,磷高效基因型膜脂过氧化程度小于磷低效基因型,并且表现出显著性差异。

Soybean cultivars with high phosphorus efficiency adapt to P stress environment easily. Previous studies have focused on the mechanism of soybean＇ s adaptation to low P stress. But the coupling effect of water and phosphorus on different P efficiency genotypic soybean is less documented. Therefore ,pot experiments were conducted in 2007 year,with P high efficient soybean Heihe 27 and P low efficient soybean Heihe 29 as materials,to determine the influence of water and P coupling on lipid peroxidation characters of different genotypic soybean at seedling stage. Two P（ applied P and without P） and four water（ 100% ,70% ,50% and 30% of the maximum field water holding capability） treatments were designed and endosmosis permeability, O2^- content, malondiaidehyde （MDA） content, relative conductivity, Superoxide dismutase （ SOD）, peroxide enzyme （POD） activity, catalase enzyme （CAT） activity, proiine content, soluble sugar content were determined. As drought stress increased,the MDA, relative conductivity and O2^- content of P high efficient soybean increased and the increasing scope was obviously smaller than that of P low efficient soybean;the decrease scope of SOD, POD and CAT activity of P high efficient soybean was remarkably smaller than that of P low efficient soybean; proline and soluble sugar content of P high efficient soybean increased obviously. The results indicate that antioxidant enzymes are related to drought tolerance and the osmotic adjustment materials are the inherent basis of superior drought tolerance of different phosphorus efficient soybean, and the lipid peroxidation degree of P high efficient soybean is significantly reduced.