【摘要】 <正> 在大豆大培上,北京五十年代前是以春作大豆为主的。后来由于冬小麦面积的不断扩大,和一年两熟制在平原水浇地区的发展,因此提出了发展夏播大豆的要求。夏大豆高产,要求相应的品种,种植方式和栽培技术。我们于1982年—1983年,探讨了夏播条件下密度对大豆生长发育的影响,以及影响产量提高的主要因素,现报告如下。更多还原

【Abstract】 Two early maturing varieties of summer-growing soybean were used in a study on planting density in 1982—1983 near Beijing.Crop yield analysis shows yield of summer-growing soybean being the result of integrating performance trait of single plant and the plant population of unit area.Analysis of crop yield formation process reveals a strong posittve correlation between accumulative dry organic matter during pre-flowering stage and leaf area index of pod-filling stage,on the one hand,and crop yield and its components,on the other.80—90 percent of the total pods and seeds were found on the middle and upper nodes of plant and constituted major part of soybean yield.It is concluded that the key factors in increasing crop yield of summer growing soybean are vigorus growth of soybean in vegetative stage and larger leaf surface area in pod-filling stage.Optimal planting for a good soybean stand and careful crop management in middle and late stages of soybean development are essential for a maximum yield of summer-growing soybean.更多还原