密度对不同类型大豆叶部性状的影响

 以耐密植品种垦丰16和普通品种绥农14为材料，设置不同种植密度小区试验，研究密度对不同耐密性大豆叶部性状的影响。结果表明：耐密植品种垦丰16产量高于普通品种绥农14，特别是在高密度条件下差异达到极显著水平；垦丰16随着密度增加光合速率和水分利用效率下降速度较绥农14慢；在栽培密度变化时叶柄长度变化没有绥农14明显，在高密度条件下冠层更加疏朗，有利于群体通风透光；绥农14随着密度增大，叶色值的峰值提前，而垦丰16的叶色值出现时期没有明显变化，且生育后期耐密品种的叶色值高于普通品种，可见叶色值峰值变化小，后期叶片持绿性强是耐密植品种的一个重要特性；垦丰16的叶形指数在3种密度条件下都高于绥农14，更有利于通风透光。从3种密度条件下产量、光合速率、水分利用效率、叶色值、叶形指数和叶柄长度的变化规律可以看出垦丰16更适于密植栽培。

Effect of density for different types of leaf traits on soybean

 Tow soybean cultivars of different density-tolerance were selected as material in different planting density conditions, and the effect of density for different types of leaf traits were studied. The results showed that: the yield of density-tolerance cultivar Kenfeng 16 was greater than non density-tolerance cultivar Suinong 14 especially in high density condition. The difference reached a significant level. The density-tolerance varieties cultivated kenFeng 16 was slower than non density-tolerance cultivar Suinong 14 on reducing rate of photosynthetic and water use efficiency with the increasing density. The variation of petiole length of density-tolerance varieties kenFeng 16 was not as great as Suinong 14 with the variation of planting density; and in high density canopy, kenFeng 16 had fewer leaves in lower part of the plant which was beneficial to ventilation and light efficiency. Along with the increased density, the peak value of leaf color appeared earlier in non density-tolerant variety Suinong 14, but no significantly change on density-tolerance varieties cultivated Feng 16. The leaf color values of density-tolerant variety was higher than the common varieties at late growth stage. The small changes of leaf color peak value and the staying-green ability of late leaf was an important characteristics of density-tolerance varieties. In three different density conditions, the leaf index of density-tolerance variety Kenfeng 16 was higher than Suinong14, it had better ventilation and light efficiency. In these three density conditions, the results of yield, photosynthetic rate, water efficiency, leaf color, leaf shape index value variation and petiole length all indicated that Ken Feng16 was more suitable for high density planting.