向日葵种质资源苗期耐盐性鉴定评价OA

In order to screen salt-tolerant germplasm resources of sunflower,171 sunflower germplasm re-sources were subjected to 0.8%salt stress,and seedling emergence and seedling survival were investigated af-ter 7 d and 14 d of treatment,respectively,and 10 seedling salt-tolerance-related traits were measured in sur-viving plants after 40d of treatment.The results showed that 116 sunflower materials in the test material had more than 60%seedling emergence rate and more than 75%seedling survival rate under salt stress.Salt stress significantly reduced plant height,number of leaves,root length,aboveground fresh weight,root fresh weight,total plant fresh weight,aboveground dry weight,root dry weight,total plant dry weight and root-crown ratio in sunflower seedlings.The 10 individual traits were transformed into four comprehensive indexes by principal component analysis,and their affiliation function values and weights were used to calculate the comprehensive salt tolerance evaluation values of different sunflower germplasm,and one highly sensitive,13 sensitive,57 intermediate,42 salt-tolerant and five highly salt-tolerant germplasm resources were identified by cluster analy-sis,respectively.Stepwise regression analysis was used to select five main evaluation indexes,including plant height,number of leaves,root length,total plant fresh weight and root dry weight,which were used in the construction of a comprehensive mathematical evaluation model.The results of this study laid a foundation for the screening of salt-tolerant germplasm resources and breeding of new varieties of sunflower.