Comprehensive evaluation of salt tolerance at seedling stage of 44 water-melon germplasm resources
Fourty-four watermelon germplasms were used as experimental materials,and 0(CK)and 150 mmol·L-1 Na-Cl was used at two treatment levels,and 15 indexes of different watermelon germplasm seedlings were determined.The salt tolerance coefficient of 15 indicators was used as the basis for salt tolerance evaluation,and multivariate analysis methods such as correlation analysis,principal component analysis,membership function value method and cluster analysis were used for comprehensive evaluation.The 15 individual indicators were converted into 4 independent comprehensive indicators by principal component analysis,and the cumulative contribution rate was 71.10%.The cluster analysis was carried out on the basis of the salt tolerance coefficient,and 10 highly salt-tolerant,21 moderately salt-tolerant and 13 weakly salt-tolerant watermelon germplasm resources were screened out according to the size of the D value.The compre-hensive salt tolerance evaluation value of each germplasm was obtained by the membership function value method,the top 5 were HY-91,DQ-308,W19-15,HY-73 and W19-10,belonging to highly salt-tolerant germplasm.