不同耕作方式、秸秆还田配施肥料条件下夏玉米磷素高效利用研究

Phosphorus Efficient Utilization of Summer Maize under Different Tillage Methods,Straw Returning and Fertilizer Application

通过大田试验研究耕作方式、秸秆还田配施不同类型肥料对土壤磷有效性和夏玉米产量的影响,以期为解决磷在玉米生产中利用效率低的问题提供参考。试验采用再裂区设计,主区为秸秆处理(秸秆还田、秸秆不还田);裂区为耕作处理,包括免耕(NT)、旋耕(RT)、深松(ST)、深松+旋耕(SRT);再裂区为施肥处理(施磷肥、有机肥,不施肥)。结果表明,秸秆还田、不同耕作方式及配施肥料显著影响玉米拔节期、抽雄期和完熟期的生物量积累和土壤有效磷含量以及产量构成因素和磷素利用效率。施磷肥或有机肥及秸秆还田均可提高土壤有效磷含量、玉米产量和磷素利用效率,且有机肥的效果显著优于磷肥。耕作处理显著影响不同土层有效磷含量,对0~20 cm土层有效磷影响表现为NT>ST>RT>SRT,而对20~40 cm土层有效磷的影响相反,表现为SRT>ST>RT>NT;耕作处理对玉米籽粒产量和磷素利用效率的影响表现为SRT>ST>RT>NT。深层土壤有效磷含量更能影响玉米对磷素的吸收同化,最终影响产量和磷肥利用效率。耕作方式和施肥对土壤有效磷含量、玉米生物量积累、玉米产量及其构成因素、磷肥利用效率均具有显著的交互作用。本试验条件下秸秆还田+施用有机肥+SRT为最佳处理组合,能够促进磷素吸收利用,提高玉米生物量、产量构成要素及籽粒产量。

In this field experiment,the effects of different tillage methods,straw returning and fertilizer application on soil P availability and summer maize yield were studied and taken as the entry points to solve the problem of low phosphorus use efficiency in crop production.The split-split plot design was adopted:the main plot was straw treatment(straw returning and no straw returning to field);the split-plot was tillage treatment,including no-tillage(NT),rotary tillage(RT),deep soiling(ST)and deep soiling+rotary tillage(SRT);the split-split plot was fertilizer treatment,including P fertilizer,organic fertilizer and no fertilizer.The results showed that straw returning,tillage measures and fertilizer application significantly affected summer maize biomass accumulation,soil available P content,yield components and P use efficiency at jointing,tasseling and mature stages.The application of P or organic fertilizers and the straw returning could increase soil available P content,maize yield and P use efficiency,respectively,and the effects of organic fertilizer were significantly better.Tillage treatments had significant effects on available P in different soil layers,and their effect on available P in 0~20-cm soil layer was NT>ST>RT>SRT,while that on available P in 20~40-cm soil layer was SRT>ST>RT>NT.The effects of tillage treatments on grain yield and P use efficiency of maize showed SRT>ST>RT>NT.The available P content in deep soil could affect the absorption and assimilation of P in maize,and ultimately affect the maize yield and the use efficiency of P fertilizer.Tillage methods and fertilizer application had significant interactions on soil available P,maize biomass accumulation,maize yield and its components,and P fertilizer use efficiency.In this experiment conditions,straw returning combined with organic fertilizer and SRT was the best treatment,which could promote the absorption and utilization of phosphorus and improve the biomass,yield components and grain yield of summer maize.