Evaluation of 8 Ipomoea batatas cultivars in xerothermic valley of Yuanmou.

The evaluation of 8 introduced Ipomoea batatas cultivars at Yuanmou showed:(i)they all grew well in Yuanmou and is adaptable to xerothermic climate;(ii)the highest yield in fresh is Chaoshu 1,a cultivar introduced from Guangdong Province,which is 62 500.0 kg/hm2,and highest yield in dry is Yusu 303,introduced from Chongqing,which is 15 281.0 kg/hm2 in dry;(iii)the cultivar Nanshu 88 and Sushu 3 were better in tuber shape;(iv)the single tuber weight of Yushu 303 was 319.3 g,which is the highest single tuber weight and most vigorous.