Study on the leaf trait variation ‌‌of Michelia chapensis clones

The morphological traits including leaf area, circumference, length, width, length to width ratio, roundness, rectangularity, and chlorophyll content on mature leaves of 109 Michelia chapensis clones grafted and preserved which from 20 districts in 5 provinces including Guangdong, Guangxi, Hunan, Jiangxi, and Guizhou, were measured and analyzed. The results showed that there were abundant variations in leaf traits of M. chapensis clones, and the coefficient of variation of these traits ranges from 3.84% to 27.98%, and the repeatability of all traits is higher than 0.70, indicating that the leaf traits of M. chapensis clones were strongly regulated by genetic factors. Additionally, the correlation results of leaf traits indicate that there were a significant correlation between each traits, and there exist a deeply significant positive correlation(p < 0.01) between the four traits of leaf area, circumference, length, and width. In addition, 8 leaf traits were transformed into 3 principal components through principal component analysis, and the cumulative contribution rate of 87.373%, reflecting the vast majority of variation information about leaf traits of M. chapensis clones. Moreover, based on the variation data of leaf traits, cluster analysis was conducted to classify 109 M. chapensis clones into four major groups(Ⅰ-Ⅳ). Furthermore, there were significant differentiation in leaf traits among these four groups, and different characteristics.