蔗糖浸种缓解玉米幼苗铜胁迫及其生理指标的灰色关联分析

为探究蔗糖浸种缓解玉米幼苗铜胁迫的能力,采用浸种法研究了342.3 mg·L^-1蔗糖浸种处理对0、100、200、400 mg·L^-1硫酸铜处理玉米幼苗生理生化指标的影响,并进行生理生化指标与玉米铜胁迫恢复指数的灰色关联分析。结果表明,蔗糖浸种可显著提高一定程度铜胁迫下玉米幼苗的株高、根长、相对根长、相对株高、过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性。生理生化指标与蔗糖处理对铜胁迫恢复指数的灰色关联度排序为:相对根长(0.799)>相对株高(0.775)>根长(0.767)>脯氨酸含量(0.749)>POD活性(0.740)>可溶性蛋白含量(0.699)>可溶性糖含量(0.673)>CAT活性(0.664)>叶绿素含量(0.647)>SOD活性(0.601)>株高(0.579)。综上可知,蔗糖浸种在一定程度上能有效缓解玉米幼苗的铜胁迫,抗性鉴定时选择相对根长、相对株高、根长、脯氨酸含量、POD活性、可溶性蛋白含量、可溶性糖含量、CAT活性等强关联指标可以提高选择效率,这为玉米抗性育种提供了参考。

Alleviation of Copper Stress and Grey Correlation Analysis of Physiological Indexes of Maize Seeding by Soaking With Sucrose

In order to investigate the alleviation of maize seeding by soaking sugar to copper stress, maize was taken as experimental materials to study the effects of 342.3 mg·L^-1 sucrose soaking treatments on the physiological and biochemical indexes of maize seedlings treated with 0, 100, 200, and 400 mg·L^-1 CuSO₄, then Grey Correlation Analysis of between the physiological and biochemical indexes and recovery index of maize under copper stress were carried out. Our results showed that, sugar soaking could significantly improve plant height, relative plant height,root length, relative root length, superoxide dismutase (SOD), peroxidase (POD), and hydrogen peroxide(CAT) of maize seedlings. The ranking of grey relational degree of physiological and biochemical indexes and recovery index of maize under copper stress was: relative root length(0.799)> relative plant height (0.775)> root length(0.767)> proline content(0.749)>POD(0.74)> soluble protein content(0.699)> soluble sugar content(0.673)>CAT(0.664)> chlorophyll content(0.647)>SOD(0.601)> plant height(0.579). Thus, sucrose immersion could effectively relieve copper stress of maize seedlings to some extent. In order to improve the selection efficiency on copper resistance of sucrose soaked maize seed, we should strengthen the selection of strong correlation indexes such as relative root length, relative plant height, root length, proline content, POD, soluble protein content, soluble sugar content, CAT and so on. These results provide references for maize resistance breeding.