棉花抗旱性综合评价及其相关性分析

Comprehensive evaluation and correlation analysis of drought resistance of cotton

为综合评价棉花种质资源的抗旱性,筛选优异抗旱品种(品系),并建立成株期产量抗旱预测模型。对50份棉花种质资源在苗期进行干旱处理,调查其表型性状并测定其生理指标,根据各性状/指标差异的显著性筛选抗旱指标,并计算抗旱系数和抗旱指数,利用主成分分析法和隶属函数法计算综合抗旱系数、综合抗旱指数、综合抗旱隶属函数值、加权抗旱性系数和抗旱性综合度量值,对棉花抗旱性进行综合评价和分级。进一步将苗期评价分级结果与成株期干旱胁迫下产量和纤维品质性状进行比较,以分析苗期抗旱鉴定模型对成株期预测的精度。苗期生理性状在提高抗旱鉴定模型精度上具有重要作用,基于苗期生理指标建立的抗旱鉴定模型能够很好地预测成株期的抗旱性。

To comprehensively evaluate the drought resistance of cotton germplasm resources,select excellent drought resistant varieties(lines),and establish drought resistant prediction model of yield in adult stage,drought treatment was carried out on 50 cotton germplasm resources at seedling stage,and their phenotypic traits and physiological indices were investigated.Drought resistance indices were screened according to the significance of trait differences,and the drought resistance coefficient and drought resistance index were calculated.The comprehensive drought resistance coefficient,comprehensive drought resistance index,comprehensive drought resistance membership function value,weighted drought resistance coefficient and comprehensive drought resistance measurement value were calculated by principal component analysis and membership function method,and the drought resistance of cotton was comprehensively evaluated and graded.The results of seedling evaluation and classification were further compared with the yield and fiber quality traits in adult stage under drought stress to analyze the accuracy of seedling drought resistance identification model in predicting adult plant stage.Physiological traits at seedling stage play important roles in improving the accuracy of drought resistance identification model.The drought resistance identification model based on physiological indices at seedling stage can predict the drought resistance at adult plant stage well.