不同磷水平对棉花养分吸收和磷肥利用效率的影响OA北大核心CSTPCD

The effects of nutrient absorption,phosphorus fertilizer utilization efficiency,biomass,and the nitrogen and phosphorus stoichiometric ratios of cotton plants under different phosphorus application rates were studied to provide a theoretical basis for determining the technical service focus of scientific phosphorus application in a cotton area of northern Xinjiang.Based on a long-term positioning experiment of phosphorus fertility succession characteristics in cotton soil that started in 2018,the response of phosphorus and cotton nutrient uptake in the cotton field under different phosphorus levels after five years of the same fertilization was analyzed.With an increase in the phosphorus application rate,the N,P,and K nutrient absorption of the cotton plants were promoted,and the average N,P,and K nutrient contents in each organ of the cotton plants ranged from 1.75 to 38.27,1.46 to 11.26 g·kg-1,and 3.11 to 24.31 g·kg-1,respectively.150 kg·hm-2 phosphorus is most conducive to the absorption and dry matter accumulation of P-quality fractions.The N∶P ratio of the cotton organs ranged from 1.20 to 12.01.The N∶P ratio of the stem,leaf,and bud/boll/shell of the cotton plants decreased with an increase in the phosphorus application rate,and the biomass of the cotton plants and seed cotton yield increased with a decrease in the leaf and(bud/boll/shell)N∶P ratios.In this experiment,cotton growth was more inclined to be limited by N and P.The utilization rate and the agronomic efficiency of the phosphorus fertilizer first increased and then decreased with an increase in phosphorus application,and the surplus of phosphorus increased with an increase in phosphorus application.When applying 150 kg·hm-2 P,the utilization rate and the agronomic efficiency of the P fertilizer showed the highest values,which were 10.20%and 4.05 kg·kg-1,respectively.The P surplus was 54.19 kg·hm-2.It is feasible to apply 150 kg·hm-2 phosphorus to cotton fields of grey desert soil in northern Xinjiang.