关键词: 空心菜, 芽期, 盐胁迫, 耐盐鉴定, 主成分分析, 聚类分析

Abstract: In this study, 9 water spinach (Ipomoea aquatica) germplasm resources were selected, and their seeds were treated with 0, 50, 100, 150, 200 mmol·L^-1 NaCl. The germination rate, germination potential, germination index and vigor index were measured. The salt tolerance of water spinach germplasm resources was comprehensively evaluated by principal component analysis and cluster analysis. The results showed that low concentration salt treatment promoted the germination of some varieties, while high concentration salt treatment significantly inhibited the germination of 9 varieties. Principal component analysis divided 11 salt tolerance related indicators into 4 principal components, with a cumulative contribution rate of 89.509%. Combined with cluster analysis, the salt tolerance of 9 water spinach germplasm was divided into 4 types. ‘Sancha’ was a high salt-tolerant variety. ‘Taiguo’ and ‘Baijun’ belonged to medium salt-tolerant varieties; ‘Jieyang’, ‘Gangzhong’ and ‘Taiwang’ belonged to weak salt tolerant varieties. ‘Bailiu’, ‘Qinggeng’ and ‘Taimei’ were salt sensitive varieties.

Key words: Ipomoea aquaticaw, germination stage, salt stress, salt tolerance identification, principal component analysis, cluster analysis