不同生育期营养液钾氮比对番茄生长和果实品质的影响

采用营养液沙培技术,在番茄第一穗果坐果后,研究营养液钾氮比的调整对植株生长、果实品质、产量和植株养分含量等的影响。结果表明,坐果后增加营养液钾氮比可促进番茄植株的营养生长,显著改善果实品质,提高番茄产量,平衡植株养分吸收与分配,但钾氮比过高又会抑制这些促进作用。T4处理(K∶N=2.5∶1)可显著提高叶片叶绿素含量,提高植株光合能力,显著改善果实品质(P<0.05),但同时也显著增加了脐腐果率。T3处理(K∶N=2.1∶1)番茄总果数最多,单株产量最高,果实品质较好,根冠比及根、茎、叶的干物质含量也最高,植株根、茎、叶钾素含量居中,氮素和磷素吸收分配情况仅次于T2处理。综合营养生长、果实品质、产量等指标,认为T3处理为番茄坐果后最适的营养液钾氮比。

Effects of K/N ratio of nutrient solution on growth and fruit quality of tomato in different growth periods

Under sand culture, after fruit setting of the first truss, the effect of K/N ratio of nutrient solution on plant growth, fruit quality, yield and nutrient content of tomato were investigated. The results showed that it can promote plants’ nutritional growth, improve fruit quality and production, balance nutrients’ assimilation and distribution of plants when the K/N ratio of nutrient solution was increased in the fruit-set period, but if the K/N ratio was too high it will inhibit the promoting effects. T4 treatment (K∶N=2.5∶1)could improve the content of chlorophyll significantly, the photosynthetic capacity could be improved too, and fruit qualities could also be improved significantly, but at the same time it markedly increased the incidence of blossom-rot fruits. T3 treatment (K∶N=2.1∶1)could get the maximum total fruit number and the highest yield per plant, and fruit quality was better. The root-shoot ratio and the content of dry matters of plant roots, stems, leaves in this treatment were also the highest. The content of K in roots, stems, leaves in T3 treatment were in the middle, and the assimilation and distribution of N and P ranked only second to T2 treatment. Considering nutritional growth, fruit quality, yield and so on, T3 treatment (K∶N=2.1∶1) was the optimal K/N ratio in the fruit-set period of tomato under sand culture.