中文摘要：

【目的】传统水肥管理是限制砂田设施甜瓜产业发展的主要因素。研究滴灌施肥条件下砂田设施甜瓜的水肥耦合效应,为该产业的可持续发展提供技术支撑。【方法】在滴灌施肥条件下,采用＂311-B＂D饱和最优设计,建立甜瓜产量、品质与水肥的回归模型,分析各因素的单因素效应、交互效应和边际效应,确定砂田设施甜瓜滴灌高产优质栽培的适宜施用量。【结果】建立了甜瓜产量、品质与灌水、氮肥、钾肥的回归模型;因素效应分析结果表明,影响甜瓜产量的主要因素是氮肥用量,其次是灌水量和钾肥用量;影响甜瓜品质的主要因素是钾肥用量,再其次是灌水量和氮肥用量;甜瓜产量、品质均随着水、肥用量的增加而先增加后降低。水、氮、钾相对于甜瓜产量与品质的交互效应也存在差异,在产量影响方面,对水而言,氮的交互效应大于钾;对氮而言,水的交互效应大于钾;对钾而言,氮的交互效应大于水。而在品质方面,对水而言,钾的交互效应大于氮,对氮而言,钾的交互效应大于水,对钾而言,氮的交互效应大于水。某一单一因子投入量偏高或偏低均不利于甜瓜产量和品质的形成,而由于水肥间的交互作用,两者配施则对产量和品质的提高具有较强的促进作用。【结论】综合考虑水、氮、钾对甜瓜产量、品质的影响,滴灌条件下,砂田设施甜瓜高产优质的水肥方案为：灌溉定额为786—796 m^3·hm^-2、施肥量N为170—227kg·hm^-2、K_2O为227—246 kg·hm^-2,可作为砂田设施滴灌条件下的灌溉施肥优化方案。

英文摘要：

[ Objective] The traditional management patterns of water and fertilizer is a limiting factor for the development of melons in a plastic greenhouse of a gravel-mulched field. So the study of the coupling effect of water and fertilizer on melons under drip fertigation has attached great importance to the sustainable development of the greenhouse melon industry in gravel-mulched fields. [ Method ] The water and fertilizer effective equations about yield and quality were set up by adopting a ＂311-B＂ D optimized saturation design method under the condition of drip fertigation, and the optimal schemes of water and fertilizer were established by means of an analytical model. [ Result ] According to the data obtained, mathematical regression models were set up based on the yield and quality respectively by quadratic regression analysis, in which water, N, and K were independent variables and the melon yield and quality parameters were dependent variables. The model analysis shows that water, N, and K significantly influence the melon yield and quality parameters, the influenced order of different factors on the melon yield as N〉water〉K and on the quality as K〉N 〉water, the yield and quality increased and then decreased as water, N, and K rates increased. The interaction effects among these factors were positive on the melon yield and quality, with the influenced order as water and N〉N and K〉water and K. Theinteraction effects of water and N was the biggest positive influence on the melon yield but negative on quality. The single factor is high or low and is not conducive to the formation of melon production, and due to the interaction effect, the combined application of water, N, and K has a stronger role in promotion of the yield and quality. [Conclusion] According to the optimal effect function model recommendation, the optimum combinations of water, N, and K2O rates ranged from 786 to796 m3.hm2,170 to 227 kg.hm2, and 227 to 246 kg.hm2, in which melon yield was over 35 000 k.hm2 and the quality grade w