麦季不同施磷量对麦玉和麦豆轮作体系作物产量及磷效率的影响

Effects of Different Phosphorus Application Rates in Wheat Season on Crop Yield and Phosphorus Efficiency in Wheat-Maize and Wheat-Soybean Rotation Systems

[目的]为研究麦季不同施磷量对陕西关中地区不同轮作体系作物产量和磷肥效率的影响,明确实现不同轮作体系作物高产高效的适宜麦季磷肥施用量。[方法]以麦玉和麦豆2个轮作体系为研究对象,设置0,75,150,225,300 kg/hm^(2)5个施磷(P_(2)O_(5))水平,分析2021-2022年和2022-2023年轮作周年作物产量、磷肥利用效率、土壤有效磷及其与施磷量之间的关系。[结果]与不施磷处理(0 kg/hm^(2))相比,试验2年仅麦季施磷处理显著增加麦玉和麦豆轮作体系小麦、玉米、大豆和周年产量(p<0.05),且轮作周年产量和磷肥效率均达到较高水平。2个轮作体系的周年产量均在施磷150 kg/hm^(2)处理最高,麦玉轮作体系显著高于施磷75 kg/hm^(2)处理(p<0.05),但麦豆轮作与施磷75 kg/hm^(2)处理间差异不显著;麦玉和麦豆轮作体系获得最高小麦产量的土壤有效磷分别为20.07,16.15 mg/kg。2个轮作体系的磷肥农学效率、磷肥偏生产力、磷肥回收效率、磷效率指数(PEI)均随施磷量的增加而降低;施磷75 kg/hm^(2)麦玉和麦豆轮作体系的PEI分别为施磷150 kg/hm^(2)处理的1.24,2.02倍,麦豆的PEI降低更显著。综合考虑粮食安全、环境安全和肥料利用率,以95%的小麦最高产量为实际目标,对应的麦玉和麦豆轮作体系施磷量分别为115,95 kg/hm^(2),可实现磷肥回收效率及较低的磷盈余,保证麦玉和麦豆轮作体系周年产量分别达到最大产量的96.23%和95.43%;麦豆轮作体系具有较低的施磷量需求。[结论]对不同轮作体系应从作物丰产、肥料高效利用和基于零盈余的管理政策考虑,进行合理的磷肥施用,以在满足作物-土壤磷养分的协调供应、保证作物高产的同时,提高磷效率。

[Objective]In order to study the effects of different phosphorus application rates in wheat season on crop yield and phosphorus fertilizer efficiency in different crop rotation systems in Guanzhong area of Shaanxi Province,the appropriate phosphorus fertilizers application rates in wheat season were defined to achieve high yield and high efficiency of crops in different rotation systems.[Methods]Two crop rotation systems,wheat-maize and wheat-soybean,were selected as the research objects,and five phosphorus application rates(P_(2)O_(5))(0,75,150,225,and 300 kg/hm^(2))were set.The annual crop yield,phosphorus fertilizer utilization efficiency,soil available P content and their relationships with phosphorus application rates were analyzed in 2021-2022 and 2022-2023.[Results]Compared with no phosphorus application(0 kg/hm^(2)),only phosphorus application in wheat season significantly increased the annual yield of wheat,maize,soybean and annual yield of wheat-maize and wheat-soybean crop rotation systems(p<0.05),and the annual yield and phosphorus fertilizer efficiency of crop rotation reached a high level.The annual yield of the two crop rotation systems was the highest in the 150 kg/hm^(2)treatment,and the wheat-maize crop rotation system was significantly higher than the 75 kg/hm^(2)treatment(p<0.05),but there was no significant difference between wheat-soybean crop rotation and 75 kg/hm^(2)treatment.The soil available P content of the wheat yield of wheat-maize and wheat-soybean crop rotation systems was 20.07,16.15 mg/kg,respectively.The agronomy efficiency,partial productivity,recovery rate and phosphorus efficiency index(PEI)of phosphorus fertilizer in the two crop rotation systems decreased with the increase of phosphorus application rate.The PEI of wheat-maize and wheat-soybean rotation systems with 75 kg/hm^(2)P application were 1.24,2.02 times of 150 kg/hm^(2)P application,respectively,and the PEI of wheat-soybean rotation system decreased more significantly.Considering food security,environmental security and fertilizer utilization rate,and taking 95%of the maximum wheat yield as the actual target,the corresponding P application rates of wheat-maize and wheat-soybean rotation systems were 115,95 kg/hm^(2),respectively,which could achieve phosphorus recovery efficiency and low phosphorus surplus,and ensure that the annual yield of wheat-maize and wheat-soybean rotation systems reached 96.23%and 95.43%of the maximum yield,respectively;the wheat-soybean rotation system had a lower P application requirement.[Conclusion]For different rotation systems,reasonable P application should be carried out from the perspective of crop yield,fertilizer efficient utilization and zero surplus management policy,so as to meet the coordinated supply of crop-soil P nutrients to ensure high yield while improving P efficiency.