Foliar application of silicon and selenium improves the growth, yield and quality characteristics of cucumber in field conditions

Abstract

Cucumber (Cucumis sativus L.) is one of the economically important vegetables. Silicon (Si) and selenium (Se) are beneficial elements for plant growth and development. However, their effects on the quality of cucumber fruit have not been comprehensively investigated. Moreover, the combined effects of these two elements on cucumber growth, yield and fruit quality remain unclear. In this study, the plants of cucumber ‘Jinyou 315′ were foliar-sprayed with Si (1 mM) and Se (0.025 mM) separately or in combination, and their effects on the growth, yield and fruit quality were investigated. The results showed that Si and Se application individually or in combination enhanced the photosynthesis, growth and yield of cucumber. Application of Si and Se respectively increased their concentrations, and accumulations of soluble sugars and amino acids in the fruit. Se addition increased the total organic acid accumulation by enhancing the levels of citric acid, malic acid and oxalic acid. In addition, added Si increased the vitamin C concentration in the fruit, while added Se increased the concentrations of total phenolics and flavonoids and decreased nitrate accumulation. These results suggest that application of Si and Se individually or in combination enhanced cucumber growth, yield and nutritional quality, and the combined effect of Si and Se was more obvious than their individual applications. This study may provide a theoretical basis for application of Si and Se in high quality cucumber production.