减氮控水对日光温室番茄-小型西瓜产量、品质及氮素利用的影响

Effects of reducing water and fertilizer rates on yield, quality and nitrogen utilization of tomato and mini-watermelon in solar greenhouse

研究日光温室滴灌施肥条件下,不同水肥组合对作物产量、品质和氮素利用的影响,综合评价优化水肥和常规水肥管理的调控效应。田间试验设置4个水氮处理,包括不施氮+常规灌溉(N0+FI)、常规施氮+常规灌溉(FT+FI)、优化施氮+常规灌溉(OPT+FI)、优化施氮+优化灌溉(OPT+OI)。测定不同处理下秋冬茬番茄-春茬小型西瓜的产量、品质以及根、茎、叶、果实氮素吸收量。结果表明:优化水氮处理(OPT+OI)番茄产量和果实可溶性糖、可滴定酸和Vc含量与农户常规水氮处理(FT+FI)无显著差异,但番茄果实的硝酸盐含量降低了66.3%(P<0.05);灌溉量相同时,减氮40%处理(OPT+FI)的小型西瓜产量相比常规施氮处理(FT+FI)提高了13.1%;OPT+OI处理果实的可溶性糖、可滴定酸和Vc含量较对照处理(N 0+FI)均显著提高。不同水肥处理下,两季作物氮在各器官的累积量均表现为果实>叶>茎>根。随着番茄的生长,果实和茎的氮素携出量占总携出量的比例分别由62.4%和5.9%增加至67.1%和6.3%,而根和叶中氮素携出量降低,OPT+OI处理果实氮素携出所占比例增量最大,促进了营养器官中的氮素向果实中转运。在当前日光温室栽培条件下,适当优化施氮量和灌溉量既可以保证作物产量和氮素吸收,同时提高果实的品质。

This study was aimed to investigate the effect of different combinations of irrigation and fertilizer on yield,quality,and nitrogen(N)utilization of crops in drip fertigated solar greenhouse.The experiment included four treatments including no N input+common irrigation(N 0+FI),farmers’N input+common irrigation(FT+FI),optimum N input+common irrigation(OPT+FI),and optimum N input+optimum irrigation(OPT+OI).The nutrient absorption,yield,quality of autumn-winter tomato and spring mini-watermelon in different treatments were determined.Compared with the practical methods of using fertilizer and water by farmers in the region,the combination of optimum N and optimum irrigation did not cause reduction of the yield,content of soluble sugar,titratable acids,and Vitamin C(Vc)of tomato,but the treatments decreased the nitrate content in fruit by 66.3%.When the irrigation amount was similar,the yield of mini-watermelon with 40%reduction in N fertilizer input was 13.1%higher than that of farmers’N input.The content of soluble sugar,titratable acid,and Vc in fruit of OPT+OI treatment were significantly higher than that of the control.The nitrogen distribution proportion illustrated as fruit>leaf>stem>root.With the growth of tomato,the nitrogen distribution proportion in fruit and stem increased from 62.4 and 5.9%to 67.1 and 6.3%,respectively,while that in root and leaf decreased,OPT+OI treatment promoted the transport of N from vegetative organs to fruit(the nitrogen distribution proportion in fruit of this treatment increased the most).It is concluded that under current cultivation conditions,yields and N uptake of crop could be obtained at optimum N and irrigation,which also have promoted the fruit quality.