Relationship between lint yield and main agronomic characters in F2 generation of upland cotton.

The results from analyzing the relationship between lint yield and main agronomic characters in F2 generation of two upland cotton cross combinations(Baimian 1×TM-1 and Baimian 1×Zhongmiansuo 12) showed that there were significant or very significant positive correlation between lint yield and main agronomic characters except for stem internodal length,the correlation coefficient,partial correlation coefficient and direct path coefficient between plant height,total fruit nodes,effective fruit branches,bolls per plant,boll weight,lint percentage and lint yield were all positive,which indicated that the direct selection of these characters was effective.The partial correlation coefficient and direct path coefficient of total fruit braches,stem internodal length and lint yield both were negative but total fruit braches had the promoting effect on lint yield by means of bolls per branch,and stem internodal length had the promoting effect on lint yield by means of bolls per plant and plant height.The regression analysis showed that the bolls per plant,boll weight and lint percentage all had significant positive effect on lint yield in two cross combinations,and there were difference in the positive effect of stem internodal length,total fruit nodes and total fruit branches on lint yield between two cross combinations.The experiment result can provide reference for yield breeding of cotton.