生化抑制剂组合与施肥模式对黄泥田水稻养分累积及利用率的影响

Effects of combined biochemical inhibitors and fertilization models on nutrient uptake and use efficiency of rice in yellow clayey field

添加生化抑制剂是提高水稻肥料利用率的有效途径之一,本研究结合不同施肥模式探讨其节肥增效的养分利用特征,以期寻找适合黄泥田地区水稻高产高效的施用方式。采用二因素随机区组设计,研究生化抑制剂[脲酶抑制剂N-丁基硫代磷酰三胺(NBPT)和N-丙基硫代磷酰三胺(NPPT)及硝化抑制剂2-氯-6-(三氯甲基)吡啶(CP)]组合与施肥模式(一次性和分次施肥)互作对黄泥田水稻养分吸收、利用和分配的影响,并探讨各养分间及其与产量的相互关系。结果表明:生化抑制剂组合和施肥模式对水稻主要生育期N、P、K累积、转运和分配的影响均存在一定的互作效应,互作条件下各生育期养分间吸收存在协同效应。尿素分次施用处理水稻成熟期N、P、K吸收量较一次性施用处理分别提高11.0%、0.9%、4.2%;氮肥吸收利用率、氮肥农学利用率分别显著提高27.5%、70.8%。不同施肥模式下,配施抑制剂组合(NBPT、NPPT/+CP)显著增加水稻N、P、K吸收量,促进抽穗后干物质生产和N素积累,提高籽粒中的养分分配及N素利用效率。新型脲酶抑制剂NPPT单独施用及与CP配施的水稻养分吸收和利用与NBPT相似。相关分析表明,不同施肥模式下水稻成熟期N、P、K吸收量与籽粒产量均呈极显著正相关。总之,通过施肥技术和抑制剂配施的集成与优化,有利于抽穗后N、P、K的吸收、转运,促进养分积累,大幅度同步提高黄泥田水稻的产量和养分利用效率。

Application of biochemical inhibitors for urease and nitrification is an effective way of improving fertilizer use efficiencyof rice.The objective of this study was to determine the characteristics of nutrient use of rice as affected by biochemicalinhibitors and fertilization models,and find the optimal yield and efficient application method in rice growing region in yellowclayey soils.It analyzed the interaction effects of biochemical inhibitors[urease inhibitors N-(n-butyl)thiophosphoric triamide(NBPT]and N-(n-propyl)thiophosphoric triamide(NPPT),and nitrification inhibitor2-chloro-6-(trichloromethyl)pyridine(CP)]with fertilization models(one-off and three-time fertilizations)on nutrient absorption,utilization and distribution ofrice,and the relationship between nutrient uptake and grain yield using two factor randomized block design.Resultsshowed that certain interaction effects was observed between inhibitor combination and fertilization model on the uptake,utilization and distribution of nitrogen(N),phosphorus(P)and potassium(K)at the main growth periods of rice.The threetimes urea fertilization treatment significantly increased N,P and K uptake(respectively by11.0%,0.9%and4.2%)at maturity,and N recovery efficiency and N agronomic efficiency(respectively by27.5%and70.8%)over those of one-off ureafertilization treatment.The addition of inhibitors(NBPT,NPPT/+CP)significantly increased N,P and K uptakes of rice,drymatter production and N accumulation after heading stage.It also improved the allocation of nutrients in grain and N useefficiency under different fertilization models.The application of new urease inhibitor NPPT alone or combined with CPhad the similar effect on nutrient uptake and use in paddy fields with NBPT.The uptake of N,P and K of rice at maturityhad significant positive correlation with grain yield under different fertilization models.In conclusion,the integration andoptimization of fertilization techniques combined with inhibitors enhanced the uptake and transport of N,P and K afterheading stage.It also promoted nutrient accumulation and at the same time significantly improved rice yield and nutrientuse efficiency in yellow clayey fields.