氮钾化肥配合追施对日光温室番茄越冬长季节栽培产量与品质的影响

采用有机基质进行番茄越冬长季节栽培试验,研究尿素和硫酸钾不同追施比例对番茄产量与品质的影响。结果表明,氮钾肥合理配施可维持番茄植株营养生长与生殖生长的平衡,促进植株生长;氮钾肥适宜配比可增加番茄座果数与单果重,提高番茄产量;并增加番茄果实中Vc、还原糖与有机酸的含量,改善果实品质。整体而言,番茄越冬长季节栽培过程中,氮钾(N∶K2O)的追施比例以1∶1.2～1.3为宜;但不同生长时期番茄对氮钾养分的需求比例不同。因此,番茄越冬长季节栽培的生长期肥料供给应采用分段式管理,前期营养生长与生殖生长均旺盛,氮钾(N∶K2O)适宜追施比例为1∶1左右;中期大量钾素随果实采收而移走,应增加钾肥施用量,氮钾(N∶K2O)追施比例宜为1∶1.2～1∶1.4;后期番茄植株营养生长下降,应重视氮钾肥平衡施用,氮钾(N∶K2O)追施比例应为1∶1.2左右。

Effects of combined top application of inorganic nitrogen and potassium on the yield and quality of overwintering tomato in greenhouse

Proper application of inorganic N and K fertilizer was important for overwintering tomato cultivation. Urea and potassium sulfate were dominant fertilizers used in local. Effects of top application of inorganic nitrogen-potassium fertilizer with different formulas on the growth, yield and quality of an overwintering tomato cultivars were studied in this paper. Results showed that proper nitrogen-potassium fertilization could maintain the balance of vegetative and reproductive growth of tomato. Balance application of N and K could promote the growth of tomato, increase the trusses number, fruit number and fruit weight effectively as well. In addition, contents of Vc, reducible sugar and organic acid of tomato were raised, which resulted in a better quality. From the point of view of whole cultivating process of overwintering tomato, the most appropriate formula of nitrogen-potassium fertilizer(N∶K₂O) for the purpose of top addressing should be 1∶1.2～1.3; However, since the demanding of N and K varied with different growth durations, batching fertilization management differed with different growth durations should be adopted. At the incipient stage of vegetative growth, both the vegetative and reproductive growth are vigorous, the appreciate ratio of N and K₂O should be 1∶1; at the middle stage, as a great deal of K was removed with the harvest of fruit, the dosage of K application should be increased therefore, thus the appreciate ratio of N and K₂O should range from 1∶1.2 to 1∶1.4; at the late stage, vegetative growth declined and balanced application of fertilizer should be paid more attention, the ratio of N and K₂O should be around 1∶1.2.