Effect of different levels of water supply on gas exchange of peach trees

Two early ripening peach cultivars were irrigated with an amount of water corresponding to different fractions of evapotranspiration calculated from class A evaporate in the postharvest phase. A rainfed control was also included. Leaf water potential, CO2 assimilation and transpiration were highly effected by water availability. Better water status, higher assimilation and transpiration rates were observed in irrigated plants. However, the physiological responses of plants supplied with the highest volumes of water were only slightly different from those observed on plants irrigated at lower rates. The possible effect of the higher carbohydrate production during the vegetative and productive cycle of early ripening peaches is discussed.