Studies on photosynthetic characteristics of plum

Many photosynthetic characteristics of mature plum SuiLi3 including effects of diurnal change, seasonal change, leaf position and leaf direction on Pn were studied. The results showed that diurnal change in Pn from plum was typical midday slump bimodal curve, with bimodal curve for seasonal change. The negative periods of the leaves in plum were 5~6 days, and the Pn was the highest in 25~28 days for leaf age. There were considerable discrepancies in Pn of different leaf position and leaf direction was important affecting factor to photosynthetic characteristics of the leaves.