Effects of mixed fertilizers formed by the compounding of two targeted controlled-release nitrogen fertilizers on yield,nitrogen use efficiency,and ammonia volatilization in double-cropping rice

One-time application of mixed fertilizer formed by the compounding of two controlled-release nitrogen fertilizers(CRUs)with targeted N supply during the periods from transplantation(TS)to panicle initiation(PI)and from PI to heading(HS)is expected to synchronize the double-peak N demand of rice.However,its effects on the yield and N use efficiency(NUE)of labor-intensive double-cropping rice were unknown.Two targeted CRU(CRU_(A)and CRU_(B))were compounded in five ratios(CRU_(A):CRU_(B)=10:0,7:3,5:5,3:7,and 0:10)to form five mixed fertilizers(BBFs):BBF1-5.A field experiment was performed to investigate the characteristics of N supply in early and late seasons under different BBFs and their effects on N uptake,yield,and ammonia volatilization(AV)loss from paddy fields of double-cropping rice.Conventional high-yield fertilization(CK,three split applications of urea)and zero-N treatments were established as controls.The N supply dropped significantly with the increased compound ratio of CRU_(B)during the period from TS to PI,but increased during the period from PI to HS.With the exception of the period from TS to PI in the late rice season,the N uptake of early and late rice maintained close synchronicity with the N supply of BBFs during the double-peak periods.Excessive N supply(BBF1 and BBF2)in the late rice season during the period from TS to PI increased N loss by AV.The effect of BBF on grain yield increase varied widely between seasons,irrespective of year.Among the BBFs,the BBF2 treatment of early rice not only stabilized the spikelets per panicle but also ensured a high number of effective panicles by promoting N uptake during the period from TS to PI and a high grain-filling percentage by appropriately reducing the N supply at the later PI stage,resulting in the highest rice yield.While stabilizing the effective panicle number,the BBF4 treatment of late rice increased the number of spikelets per panicle by promoting N uptake during the period from PI to HS,resulting in the highest rice yield.The two-year average yield and apparent N recovery efficiency of the BBF2 treatment during the early rice season were 9.6 t ha 1 and 45.3%,while those of late rice in BBF4 were 9.6 t ha 1 and 43.0%,respectively.The yield and NUE indexes of BBF2 in early rice and BBF4 in late rice showed no significant difference from those of CK.The AVs of BBF2 during the early rice season and of BBF4 during the late rice season were 50.0%and 76.8%lower,respectively,than those of CK.BBF2 and BBF4 could effectively replace conventional urea split fertilization in early and late rice seasons,ensuring rice yield and NUE and reducing AV loss in paddy fields.

花生控释掺混肥减量使用效果

在花生控释掺混肥基准施肥量的基础上,设6个施肥处理,处理1、2、3、4分别为花生控释掺混肥750、675、600、450 kg/hm^(2),处理5为普通三元复合肥750 kg/hm^(2),处理6为不施肥,考察控释掺混肥减施增效情况。结果表明,花生控释掺混肥增产显著,与处理6相比,处理1、2、3、4分别增产19.6%、18.8%、18.2%、14.8%;与处理5相比,处理1、2、3增产均较多;随着花生控释掺混肥施用水平的降低,花生产量下降,但减产不显著。花生控释掺混肥600 kg/hm^(2)(减施20%)收益高于其他处理,是减施增效较为理想的方案。

花生钾肥与有机肥配合效应研究

对花生在常规施NP肥的基础上 ,进行了钾肥和有机肥配施试验。结果表明 ,在NP、NPK、NPOM、NPKOM 4个处理中 ,以NPKOM增产效果最好 ,其次为NPK ,再次为NPOM ,均较对照NP存在极显著差异 ,且分别较对照增产 1 6 2 3.31kg/hm2 、6 59.99kg/hm2 、583.32kg/hm2 ,增产 94 .8%、38.5%、34 %。在NP的基础上 。

夏花生优化配方施肥模型的研究

本文根据1990～1991两年5个试点,不同氮、磷组合,二因素五水平回归设计田间试验测得的参数,建立了夏花生优化配方施肥模型为y=141.1461+5.0989x_N+5.4628x_P-0.1410x_N^2-0.2352x_P^2-0.071x_Nx_P,进而求得,最大施肥量为纯氮15.86kg/亩,P_2O_59.27kg/亩,并对氮、磷互作及单因素的增产效应进行了剖析。