Abstract:

【Objective】 The purpose is to explore the responses and their mechanisms of cucumber plant to different light qualities in greenhouse. 【Method】 Cucumber (Cucumis sativus L. cv. Delstar) was planted in greenhouse with 10 h (7：30-17：30) of supplemental different light qualities such as red light (650 nm) and blue light (450 nm), and white light as control. The effects of supplemental different light qualities on plant growth, photosynthesis, biomass partition, early fruit yield were investigated. 【Result】Maximum and minimum temperature under supplemental red lighting was higher than those of supplemental white and blue lighting. The specific leaf area of red and white treatments was lower than that of plants grown under supplemental blue treatment. The chlorophyll content and dry matter production of white treatment was lower than that of red and blue treatments. Red treatment were higher and had more leaves and larger leaf area than that those of plant grown under white and blue treatment. The root, stem and leaf-partitioning index of red treatment were higher than those of blue and white treatments. Leaf photosynthesis rate and Fv/Fm of red treatment were higher than those of white and blue treatments. Fo and maximal ETR under white treatment were higher than those of red and blue treatments. The leaf stomatal conductance, Fo, and fruit-partitioning index under blue treatment were higher than those of white and red treatment. 【Conclusion】 The dry matter production under supplemental red and blue light increased because the photosynthesis rate, leaf area and specific leaf area increased. Greenhouse cucumber under supplemental blue light got highest marketable production per plant because supplemental blue light can promote more assimilation partitioning to fruit.

Key words: cucumber (Cucumis sativus L.)')">cucumber (Cucumis sativus L.), red light, blue light, dry matter production and partitioning, photosynthesis characteristic