中间偃麦草苗期抗旱性综合评价及对干旱胁迫的生理响应OA

Ten accessions of Thinopyrum intermedium were subjected to drought stress simulated by 15%polyethylene glycol(PEG)in hydroponic culture.Plant height,root length,shoot dry weight,root dry weight,and other indices were measured.Correlation analysis,principal component analysis,member-ship function analysis,and cluster analysis were integrated to comprehensively evaluate drought resistance,and the differences in physiological responses among accessions with contrasting drought resistance were analyzed under drought stress.The results showed that all the indices were positively correlated with each other in all accessions under drought stress(P＜0.01).Multivariate statistical analysis was used to calcu-late the comprehensive evaluation values of drought resistance(D value)of ten accessions of Thinopyrum intermedium,and based on D value,cluster analysis classified them into three drought-resistant categories:three highly drought-resistant accessions,five moderate drought-resistant accessions,and two weak drought-resistant accessions.The highly drought-resistant accessions of Thinopyrum intermedium enhanced their drought resistance through increasing antioxidant enzyme activities and osmotic content.In this study,the highly drought-resistant accessions of Thinopyrum intermedium were identified,and their physiological mechanisms of drought resistance was illustrated,thus providing a theoretical basis for the breeding of new drought-resistant varieties.