近年来,在相当一部分黄胶土壤上,尤其在河南省南阳地区东部,种植大豆或绿豆作物生长迟缓,植株瘦小,前中期叶片失绿变黄,导致产量降低,甚至个别地块颗粒未收。增施磷、氮肥以后也无明显效果。经过近3年的田间调查和小面积试验,终于摸清了发病的原因,找出了 In recent years, a considerable part of the yellow soil, especially in the eastern part of Nanyang in Henan Province, planting soybean or mung bean crop growth retardation, thin plants, green leaves turn yellow before and after mid-term, leading to reduced production, and even individual plots did not receive grain. Increased phosphorus, nitrogen fertilizer after no significant effect. After nearly 3 years of field investigation and small area test, finally found out the cause of the disease, find out