从四年桑田配施磷钾肥肥效试验中,基本得出混合配施磷钾肥不仅能增加桑叶产量11.31～14.10%,而且能提高桑叶中氮磷钾三元素的含量,钾肥比磷肥提高三元素含量的作用更明显,为了探索合理配施氮磷钾肥,提高肥料利用率,83年开始我们从桑树吸收养份与施肥量的关系试验,84年进一步从桑树吸收三元素比例与施肥量,对土壤 From the experiment of applying P and K fertilizer in mulberry fields for four years, it was basically concluded that the mixed application of P and K fertilizer could not only increase the yield of mulberry leaves by 11.31-14.14%, but also increase the contents of N, P and K in mulberry leaves, In order to explore the rational application of nitrogen, phosphorus and potassium fertilizers and improve the utilization of fertilizers, we began to test the relationship between nutrient absorption and fertilizer application rate from mulberry trees in 83 years. In the experiment of 84 years, On the soil