磷肥用量对四川主产区冬油菜籽产量和经济效益的影响OA

[Objective]Sichuan Province is a major rapeseed-producing region in the upper reaches of the Yangtze River.Rapeseed is sensitive to phosphorus(P)deficiency,which often leads to yield reduction.This study conducted field experiments on the effects of phosphorus application in the winter rapeseed-producing regions of Sichuan,aiming to provide a scientific basis for rational phosphorus fertilizer application in these areas.[Method]During 2019-2020,one experimental site was established in each of the four major winter rapeseed-producing regions of Sichuan:the West Sichuan Plain,the Central Sichuan Hilly Region,the Northeastern Sichuan Basin Marginal Mountainous Area,and the Southwestern Sichuan Mountainous Area.Six phosphorus application rates(0,45,90,135,180,and 225 kg/hm²)were set to investigate the effects of different phosphorus levels on rapeseed yield,oil yield,yield components,and economic benefits.[Result]Phosphorus application significantly increased rapeseed yield across the different major production regions in Sichuan Province.With increasing phosphorus application rate,rapeseed yield first increased significantly and then plateaued or decreased(P<0.05).At the Mianyang,Deyang,and Yibin experimental sites,when the phosphorus application rate exceeded 90 kg/hm²,the yield-increasing effect was no longer significant.Phosphorus application primarily increased rapeseed yield by increasing the number of pods per plant and the number of seeds per pod.The trend in aboveground dry matter accumulation at maturity across the experimental sites,in response to increasing phosphorus application rate,was similar to that observed for rapeseed yield.In terms of output-to-input ratio,the economic benefits under the 45 and 90 kg/hm² phosphorus application treatments were significant at all four experimental sites.When the phosphorus application rate exceeded 90 kg/hm²,the output-to-input ratio showed a decreasing trend.[Conclusion]For the goal of green and efficient rapeseed production,the recommended phosphorus application rate in the major winter rapeseed-producing regions of Sichuan Province is 90 kg/hm².