【摘要】 用¹⁵N 示踪法进行盆栽试验,研究稻草和稻根对于尿素肥效的作用.结果表明:在水稻和小麦上,稻草处理都有增加尿素¹⁵N 在土壤中的生物固持作用和减少其损失的效果.分析植株上谷/草的 dff 比值,表明稻草处理提高尿素¹⁵N 运转到稻谷和麦粒的相对比率.当水稻迟栽情况下,植株对肥料的依赖性增强,因而稻草和稻根处理更明显地促进植株对尿素¹⁵N 的吸收量和转化率.试验得出的“激发效应”,在水稻上为正的而在小麦上为负的.更多还原

【Abstract】 The ¹⁵N tracer method was used to study the effect of rice straw and stubbles plowed under insoil on the crop response to urea in pot experiments.The results are as fallows:treatment with straw increasedthe amount of immobilized ¹⁵N and thus reduced the ¹⁵N loss in both rice and wheat experiments.On the ba-sis of the specific dff of the grain and straw showed the rice straw treatment was the increase in the proportionof ¹⁵N transferred into rice and wheat grains.When the rice seedlings were planted later the plants’depen-dence on the fetilizer was increased.The treatments with both straws and roots increased the absorption ofurea- ¹⁵N and thus the rate of recovered ¹⁵N was more significant.The“priming effect”of fertilizer on soilN was positive in paddy soil while it was negative in wheat cropping.更多还原