近年来,我们在沙壤土上进行夏甘薯高产栽培试验。1979、1980两年,种植夏甘薯亩产连续超过6000斤。其生长动态及合理指标是:1.叶面积系数。栽蔓后一个月左右叶面积指数上升的快慢与产量的关系很大(见表1)「。由表看出,叶面积指数前期上开,中期平稳,后期缓慢下降,收获前略低于3,这 In recent years, we conducted summer sweet potato high yield cultivation trials on sandy loam soil. In 1979 and 1980, planting sweet potato per mu for more than 6,000 pounds. Its growth dynamics and reasonable indicators are: 1. Leaf area coefficient. The leaf area index rose about a month after planting, and the yield was very much related to the yield (Table 1). "From the table, the leaf area index started up earlier, medium-term and then slowly declined, slightly lower than 3 before harvest ,This