1944—1980的36年里,大豆产量没有玉米和其它粮食作物增长得快。Sinclair 等应用数学模型论证了大豆产量之所以受到限制是因为本身生物固 N 和根吸收的结合 N 都不能充分满足豆荚生长的需要。Boote 等认为,大豆荚果充实期间,N 素从叶片中转移出去,必然会降低净光合作用。本实验室1980年的资料表明,大豆品种 Lee 能获得种子充实时所需的 N 素,而叶片中的 N 素没有明显降低。Brevedan 等人的 N 素平衡试验证明,在荚果充实初期,并不存在纯碎消耗叶片中的 N 来供给豆荚生长的现象。在荚果充实的中期和后期,豆荚中 N 积 In the 36 years between 1944 and 1980, the output of soybeans did not increase rapidly for corn and other food crops. Sinclair et al. Applied mathematical models to demonstrate that the reason why soybean yield is limited is that the combination of biosynthetic N and root absorption N can not fully meet the needs of pod growth. Boote and other think that during the enrichment of soybean pod, N transferred from the leaves, will inevitably reduce the net photosynthesis. Data from our laboratory in 1980 showed that soybean Soybean Lee was able to obtain the required amount of N for seed enrichment, while the amount of N in the leaves was not significantly reduced. Brevedan et al.’s N-balance assay demonstrated that in the early stages of pod filling, there was no phenomenon in which purely broken kernels consumed N in the leaves to provide pod growth. N pectin in pods during mid and late pod filling