关键词: 油菜素内酯, 黄瓜, 亚适宜温光盐环境, 抗氧化系统, 光合作用

Abstract: In order to reveal the phenotypic variation patterns in the leaf- and fruit traits of naturalLitsea cubeba populations in different distribution areas, an investigation was made on the leaf- and fruit traits of ten natural L. cubeba populations distributed in 7 provinces in the south of Yangtze River. There were significant differences in the leaf- and fruit traits among and within the populations. The mean phenotypic differentiation coefficient (V_st) among the populations was 60.19%, and the variation among the populations was higher than that within the populations, suggesting that the variance among the populations was the main part of the phenotypic variation. The V_st values of fruit shape, leaf shape, fruit weight, and seed weight were 51.27%, 6666%, 54.57% and 72.29%, and the coefficients of variation (CV) for the four phenotypic traits were 6.60%, 16.91%, 19.71% and 13.40%, respectively. Due to the lower V_st and CV of fruit phenotype, the stability of fruit traits was higher than that of other traits. There existed significant correlations among 10 phenotypic traits, but the phenotypic traits had poor correlation with geoclimate factors. The ten L. cubeba populations could be clustered into four groups, but the clustering was not according to the geographic distance because the Mahalanobis distance calculated from all phenotypic traits had no significant correlation with geographic distance, which further revealed that the phenotypic variation of L. cubebaleaf- and fruit traits was spatially discontinuous. These findings provided a foundation for the preservation of L. cubeba germplasm resources and the formulation of related breeding strategies.

Key words: brassinolide, Cucumis sativus, suboptimal temperature, light, and salt environment, antioxidant system, photosynthesis.