CO2施肥对大棚油桃光合作用及产量品质的影响

棚内CO

The Effects of CO2 Enrichment on Photosynthesis, Yield and Quality of Nectarine in Greenhouse

The CO2 concentration inside the greenhouse fluctuated within a much wider range than that outside the greenhouse. The insufficiency of CO2 in the greenhouse might become the primary restrictive factor for photosynthesis especially in sunny days when photosynthesis was vigorous and the greenhouse was badly ventilated. Diurnal variation trend of net photosynthesis(Pn) of ‘Shuguang’ nectarine was a two-peak curve in open field, but the diurnal variation trend of Pn inside the greenhouse was a three-peak curve and the maximum Pn appeared at about eight O'clock in the morning, two hours earlier than that in open field. Average Pn in a sunny day inside the greenhouse was 5.97(CO2)μmol/m2*s，17.25% lower than average Pn (7.00CO2μmol/m2*s)in open field.CO2 enrichment inside the greenhouse had the important effects on the photosynthesis, yield and fruit quality of nectarine. Pn and PUE during 8:00～12:00 O'clock was markedly enhanced. Diurnal average Pn was 6.95(CO2)μmol/m2*s，25.90% higher than that of control plot. CO2 enrichment made the trees grow healthily and strongly. Biomass exclusive of fruits increased by 12.4%. The yield was 19.80% higher than that of the control and the fruit quality was also improved.