Difference Analysis of Boll Weight and Lint Index of Cotton between Chinese and American Varieties

Based on the results of the national cotton regional test check varieties in China and America,this paper utilized analyzing methods including simple correlation analysis,cluster analysis and path analysis for studying the relationship between boll weight and lint index of cotton in a multi-perspective way.The results indicated that lint yield was higher in Chinese varieties which maintained the traits of high lint index and big bolls. The path analysis showed that boll weight and lint index had a relatively greater positive direct effect on lint yield. The effects on lint yield ranked as lint index boll weight in Chinese varieties but the comprehensive and direct effects ranked as boll weight lint index in American varieties. The American varieties also kept higher comprehensive and direct effects than Chinese varieties. The simple correlation analysis also indicated that boll weight had a relatively positive correlation with lint index,and the simple correlation coefficient was 0. 947 and 0. 540 in Chinese and American varieties,respectively.Our results indicated that the contribution rates of boll weight and lint index to the yield were different between two countries' varieties,and the synergetic raise margin of boll weight and lint index was higher in Chinese varieties.