水氮耦合对温室番茄耗水特性及产量品质的影响机理及模型模拟研究

With the development of facilities agriculture, the consumers are paying more and more attention to the fruit quality because the tomato yield has met their demand. The regulating of water and nitrogen are important measurements that affect the growth, water and nitrogen use, yield and fruit quality of tomato. Exploring the qualitative and quantitative relationship between water and nitrogen coupling and tomato water use, yield and quality can provide useful guidance for the accurate irrigation management. In this study, the field, pot experiment and estimated model are conducted with tomato in greenhouse. The objectives of this study are to understand the response mechanism of the growth, physiology, water consumption characteristics, yield and quality to the water and nitrogen coupling; The estimated model considered the stress of water and nitrogen and partial wetting irrigation pattern is conduced to estimate accurately the evapotranspiration and its components of tomato; Based on evapotranspiration model, the effect of water and nitrogen deficit on water productivity and harvest index are studied to improve the accuracy of AquaCrop model to simulate the growth and yield of tomato. The sensitive parameters of fruit quality to water-nitrogen are selected, and evaluation method of comprehensive fruit quality is produced. Optimal irrigation decision-making methods are evaluated considering the demand of water and nitrogen, fruit quality, yield and benefit for tomato. Our results can determine high efficiency irrigation and fertilization strategy, and provide scientific basis for the efficient development of tomato industry in greenhouse.

随着设施农业的发展，番茄产量已经能够满足人们的需求，但消费者对番茄品质要求日益提高。水氮调控是影响番茄水肥利用、产量及品质最重要的管理措施。探索水氮耦合与番茄水分利用、产量和品质的定性和定量关系，有助于实现更加精确的亏缺灌溉施肥管理。因此本项目以日光温室滴灌番茄为研究对象，采用温室试验、室内盆栽试验及数值模拟等手段，揭示番茄耗水特性、产量以及品质对水氮耦合的响应机理。考虑水氮亏缺及局部湿润灌溉模式，构建更为精确的温室番茄蒸发蒸腾量及其组分估算模型，在此基础上量化水氮亏缺对水分生产力和收获指数的影响，提高AquaCrop模型模拟温室番茄生长和产量的精度；优选出水氮响应敏感型的品指标质，提出番茄综合品质指标评价体系，建立水氮-综合品质函数；依据水氮需求-品质-产量-效益综合评价方法，确定节水调质高效灌溉施肥模式，为温室番茄高效优质生产提供科学依据。

探索水氮耦合与番茄水分利用、产量和品质的定性和定量关系，有助于实现更加精确的亏缺灌溉施肥管理。因此本项目以日光温室滴灌番茄为研究对象，研究不同水氮条件下，番茄生长及生理特性；监测耗水过程，确定精确的模型进行模拟分析；研究番茄产量品质对水氮调控的响应机理，筛选水氮敏感型因子，提出水氮-产量模型及水氮-品质模型；综合考虑水氮需求-品质-产量-效益关系，提出基于水氮-产量-品质-效益的灌溉施肥决策方法。研究结果表明：(1) 番茄生长指标受到水、氮、水氮交互作用的影响显著，同一氮肥水平处理下，茎粗、株高和叶面积指数随水分亏缺增大而增大；同一灌溉水平处理下，番茄茎粗、株高和叶面积指数随施氮量增加而增加; 一定范围氮素亏缺可提高光合能力。(2) 番茄耗水、产量及品质受水、氮、水氮交互作用的影响显著；全生育期耗水随着水氮胁迫的增加而减小。水分对番茄产量、单果重、有机酸及番茄红素呈亏水抑制规律，对可溶性固形物及VC呈亏水促进规律，氮素对番茄产量、单果重、可溶性固形物及VC整体呈现中低水平促进，过高抑制的规律；番茄水分利用效率在中水高氮处理下达到最大值，氮素利用效率均在高水低氮处理下达到最大值。(3) 现有的作物系数法及P-M模型估算精度存在问题。基于ET与LAI的线性关系，提出氮素胁迫因子，修正了作物系数，提高了作物系数法模拟精度；提出了分阶段Jarvis模型，提高了P-M模型估算精度。(4) 量化wp*和HI0与水氮亏缺程度量化关系，提高AquaCrop模型产量模拟精度；在水分生产函数中引入了氮素因子，筛选出以Minhas模型为基础的水氮-产量模型为最优模型；构建水氮-品质模型，筛选出以Rao模型为基础的水氮-品质模型为最优模型。(5) 综合考虑水氮-产量关系、水氮-综合品质关系及水氮-效益关系，提出了基于水氮-产量-品质-效益的灌溉施肥决策方法。该研究成果可为番茄优质安全生产及智慧农业平台科学决策提供理论基础。