化肥减量配施有机肥与密度互作对土壤养分和胡麻产量的协同提升OA

This study was conducted to investigate the interactive effects of reduced chemical fertilizer application combined with organic fertilizers with planting density on soil nutrient dynamics and flax yield,aiming to the reduction of fertilization and the increase of flax yield.Field experiments were conducted at the Gaoping Experimental Station of Pingliang Academy of Agricultural Sciences during 2023-2024.Three fertilizer ratios were established with 20%organic fertilizer+80%chemical fertilizer nitrogen(F1),50%organic fertilizer+50%chemical fertilizer nitrogen(F2),and 80%organic fertilizer+20%chemical fertilizer nitrogen(F3).The planting density were set as 4.5 million seeds·hm-2(D1),6 million seeds·hm-2(D2),and 9 million seeds·hm-2(D3).The control treatment(CK)was set as the chemical fertilizer dosages of N,P2O5,and K2O with 90,45,and 54 kg·hm-2 without organic fertilizer,respectively,and the planting density of 6 million seeds·hm-2.The interactive effects between reduced chemical fertilizer application combined with organic fertilizers and planting density on soil organic matter,total nitrogen,available potassium,as well as flax growth and yield were analyzed.Relative to planting density,fertilization exerted a more pronounced influence on soil nutrient and flax yield.The application of organic fertilizer markedly enhanced soil nutrient content in 0-20 cm soil layer.The application of 80%organic fertilizer was greatly significant.Compared with CK and F1 condition,the F3D1 and F3D2 treatments significantly increased the contents of organic matter,total nitrogen and available potassium by an average of 7%,12%and 29%,respectively.Reduced chemical fertilizer application combined with organic fertilizers effectively increased in the number of mature flax plants.The accumulation of aboveground dry matter was significantly increased by 15%-49%in F3D2 and F3D3 treatments,respectively,compared with CK.Under the same fertilization conditions,F3 was increased by 42%-48%and 14%-38%,respectively,compared with F1 and F2.Reduced chemical fertilizer application combined with organic fertilizers also led to significant improvements in effective branching,seed number per pod,individual plant productivity,and yield.Compared with CK,flax yield increased by 2%-33%,with F3D2 achieving the highest yield,representing an average increase of 8%-15%over two growing seasons relative to other treatments.Comprehensive analysis demonstrated that reduced chemical fertilizer application combined with organic fertilizers enhanced soil nutrient retention,supply capacity,and buffering capability,thereby ensuring a sustainable nutrient supply for crop growth.The F3D2 treatment could be recommended as the optimal combination of organic-inorganic fertilizers and planting density for soil fertilization and increasing flax yield.