陆地棉种质苗期抗旱性鉴定OA

To elucidate the intrinsic relationship between phenotypic traits and drought tolerance at seedling stage,and screen and validate superior drought-tolerant germplasm,13 traits of 200 Gossypium hirsutum cultivars(lines)were evaluated under well-watered(CK)treatment and polyethylene glycol(PEG)induced drought stress(DS).The results showed that 13 traits conformed to normal distributions.Drought stress caused especially changes in leaf-related traits.Compared with CK,DS treatment significantly affected both morphological and physiological indices.Under DS treatment,the root development was tightly coupled with biomass accumulation,and leaf water content showed a highly significant positive correlation with both shoot fresh weight and root fresh weight.Principal component analysis got 5 principal components,which explained 71.37%of the total variance.Based on comprehensive drought-resistance index(D value),200 Gossypium hirsutum cultivars(lines)were classified into 5 groups,and 14 cultivars(lines)with highly drought-resistance were identified,which provided elite resources for breeding drought-resistance cotton and gene discovery.