长期地膜覆盖和施肥条件下玉米生物产量及其构成的变化研究

Studies on Changes of Corn Biomass Yield and Its Components Under the Condition of Long-term Plastic Film-mulching and Fertilization

通过对连续18年的棕壤长期定位试验研究表明:长期地膜覆盖和施肥后使玉米生物产量和经济产量比对照显著增加。地膜覆盖比裸地栽培有更显著的增产作用,但当地膜覆盖到一定年限后生物产量和经济产量开始呈现下降趋势。各肥料处理表现为施有机肥比施氮肥效果要好,有机肥与氮肥搭配(1∶1)施用比单一施用氮肥要好。肥料施用量加倍后多数处理间产量增加显著。长期地膜覆盖和施肥后增加了玉米的茎、叶、穗轴和根的干物重,而覆盖一定年限后根系干物重却开始显著降低,长期地膜覆盖和施肥提高了子粒占全株总生物量的比例,而降低了根系占全株总生物量的比例。

The results of long-term（lg years） brown earth located experiment showed that corn biomass yield and economic yield with long-term plastic film-mulching and fertilization increased obviously comparing with CK. but biomass yield and economic yield began to decrease when soil reached the number of years of certain mulching. The effects of manure, chemical nitrogen fertilizer and manure combined（1：1） application were better than that of single nitrogen application. Yields in more treatments increased significantly after the rates of fertilizer application were doubled. Long-term mulching and fertilization increased dry weight of stem, leaf, axle and root of corn, but dry weight of root was decreased obviously after mulching some years. Long-term mulching and fertilization improved the ratio of seed yield to biomass yield, but the ratio of root yield to biomass yield declined.