Abstract: Root system and canopy of potato are main factors for forming tuber yields. Root pulling resistance had a outstanding positive linear correlation to canopy cover degrees, i. e., the larger root pulling resistance is, the exuberanter canopy and the higher tuber yields is. Canopy cover degrees had a outstanding positive linear correlation to tuber expansive speeds. The canopies increase along with the plant age. Different varieties were various canopies. The tuberization stage were various due to different varieties. Tuber expansive speeds had a raise of straight line from the squaring to maturity. Different varieties had different expansive speeds. Therefore,according to quantitative datum of canopies, we can predict high or low yields of potato tuber, and it can also become an hoportant scientific basis for selection high yields varieties. The results indicated that varieties of good economic characters, strong drought resistance and high yields were Wumeng 851, Xishu 1. They were suitable to planting in the dry areas. But Zihuabai, Bashu 10 etc. infected late blight easily. They can not be spreaded in large areas.

Key words: Potato, Root pulling resistance, Canopy cover degrees, Tuber expansive speed, Tuber yield, Dryland tillage

CLC Number: 

• S532.01