Optimization of walnut water-fertilizer coupling scheme based on yield quality and water-fertilizer utilization efficiency
Aiming at solving low water and fertilizer utilization efficiency of walnuts in arid areas and exami-ning problems with water and fertilizer systems,we took walnut trees in the Aksu region of Xinjiang as the research object and set improving walnut quality and efficiency as the goal to study the effects of water and fertilizer coupling conditions on physiological growth indexes,fruit quality,and yield of drip-irrigated walnuts.Irrigation volume(W1:225 m3·hm-2;W2:300 m3·hm-2;W3:375 m3·hm-2),and fertilizer application amounts including F1(236.9 kg·hm-2):half conventional fertilizer application;F2(473.85 kg·hm-2):conventional fertilizer appli-cation;and F3(947.7 kg·hm-2):double conventional fertilizer application were used as test factors.To predict the irrigation and fertilization system more accurately,a binary quadratic regression model was established to study the walnut fruit quality,yield,water use efficiency,and fertilizer productivity.The Non-dominated Sorting Genetic Algorithm Ⅱ(NSGA-Ⅱ)was modeled to verify and solve the regression model and get the optimal irrigation and fer-tilization combination.The results showed that both factors of water irrigation and fertilizer application as well as their coupling effects had significant effects on the growth indexes of walnuts.The fruit quality,yield,and water and fertilizer utilization of walnuts showed a trend of increasing and then decreasing with the increase of water irriga-tion and fertilizer application.The W2F2 treatment was the optimal irrigation and fertilization treatment.The opti-mum water and fertilizer regimes simulated by NSGA-Ⅱ were 336.93 m3·hm-2 and 715.21 kg·hm-2 for irrigation and fertilizer application,corresponding protein content,yield,water use efficiency and partial fertilizer productivity were 21.36％,2 971.66 kg·hm-2,8.76 kg·mm-1·hm-2,and 1.02,respectively.
walnutdrip irrigationwater and fertilizer couplingwater use efficiencyfertilizer partial pro-ductivityNSGA-Ⅱ algorithm
万方数据
维普
