[Combined effects of enhanced UV-B radiation and doubled CO2 on tomato growth and its fruit quality].

The study on the effects of 8.40 kJ x m(-2) UV-B radiation, 700 micromol x mol(-1) CO2 concentration, and their combination on tomato (Lycopersicon esculeutum ) growth and its fruit quality showed that under enhanced UV-B radiation, the plant height, fresh weight, dry weight, photosynthesis rate, water use efficiency, and contents of total chlorophyll, chlorophyll a, chlorophyll b, soluble protein, ascorbate acid (Vitamin C) and lycopene were decreased, which resulted in the deterioration of tomato fruit quality. Doubled CO2 concentration alone accelerated tomato growth, and accordingly, ameliorated its fruit quality. Under the combined effects of enhanced UV-B radiation and doubled CO2 concentration, tomato growth and its fruit quality were not significantly different from the control. It was suggested that the positive effects of doubled CO2 could lighten and counteract the negative effects of UV-B radiation under combined treatment of enhanced UV-B radiation and doubled CO2 concentration.