For maturity and percentage of shell with lower heritability,indirect selection correlated with other characters or late generation selection can be utilized.

• 出苗-现蕾、现蕾-开花、开花-成熟、皮壳率等性状的遗传率较低,应根据各性状间相关关系进行间接选择或将选择推迟到晚期世代进行。