Combined effects of enhanced ultraviolet-B radiation and doubled CO2 concentration on growth, fruit quality and yield of tomato in winter plastic greenhouse

Abstract

Five different doses of ultraviolet-B (UV-B) radiation were supplied to tomato (Lycopersicon esculeutum. Mill) with the doubled CO₂ concentration (700 μmol · mol ^1) in the winter plastic greenhouse. The influences on the seedling growth, fruit quality and yield of tomato were investigated. Results showed that the seedling growth, and the contents of UV absorbing compounds, soluble sugar, organic acid, vitamin C and lycopene of tomato fruits, and yield of tomato increased under doubled CO₂ concentration. Under the doubled CO₂ concentration the effects of lost doses of UV-B radiation could further promote the effects of doubled CO₂ concentration. However, there is no significant increase in yield of tomato. The best dose of UV-B radiation is about 1.163 kJ · m ^2. When the dose of UV-B radiation is more than it, the effects of UV-B will be reduced.