ABSTRACT

Under the current context of reducing chemical N input in agriculture, it is important to investigate better N allocation to different growth stages of crops. The plants were subjected to sufficient and reduced soil water regimes in interaction with two N application proportions applied at the vegetative and reproductive growth stages of tomato plants, respectively. In terms of the soil water impact, across the N proportion treatments, the reduced water treatments significantly decreased leaf and biomass growth by 33% and meanwhile remarkably reduced stomatal conductance of leaves, which significantly decreased water consumption by 41%. Consequently, plant WUE markedly decreased by 10.4%. The N uptake and fresh yield were considerably reduced by 37.5% and 39.3%, respectively. Regarding the N proportion effect across the soil water treatments, the lower N application of 30% at the vegetative growth stage significantly enhanced photosynthesis products allocated to fruits, which substantially improved the fresh yield by 32.9%. Furthermore, it significantly improved N accumulation by 9.0% compared to the higher N application of 70% at this stage. Conclusively, when given the certain amount of N supply, the N allocation should be reduced at the vegetative growth stage to achieve high yield and N uptake in tomato production .

摘要

在当前减少农业化学氮投入的背景下，研究如何更好地分配氮素到作物的不同生长阶段是很重要的。分别在番茄植物的营养和生殖生长阶段，与两种施氮比例相互作用，使植物经受充足和减少的土壤水分状况。在土壤水分影响方面，在 N 比例处理中，减水处理显着降低了叶片和生物量生长 33%，同时显着降低了叶片的气孔导度，显着降低了 41% 的耗水量。因此，工厂 WUE 显着下降了 10.4%。氮吸收和新鲜产量分别显着降低了 37.5% 和 39.3%。关于土壤水处理的 N 比例效应，营养生长阶段30%的低施氮量显着提高了分配给果实的光合作用产物，从而显着提高了鲜产32.9%。此外，与现阶段 70% 的较高 N 施用相比，它显着提高了 9.0% 的 N 积累。综上所述，在给定一定的氮供应量的情况下，应在营养生长阶段减少氮的分配，以实现番茄生产的高产和氮吸收。