Photosynthetic Characteristics In Leaves Of Whangkeumbae And Yali

Many photosynthetic characteristics of Whangkeumbae and Yali were studied, such as diurnal and seasonal changes in net photosynthetic rate (Pn),the effects of the environmental factors on diurnal and seasonal changes in Pn,the effects of photosynthetic active radiation, CO2 concentration,air temperature and air humidity on photosynthesis of mature leaves,the photosynthetic characteristics and chlorophyll fluorescence parameters in natural light and simulated light, whether photoinhibition occurred or not in high light.Some significant results have obtained as the followings:1. On sunny day, diurnal changes in net photosynthetic rate(Pn) in Whangkeumbae and yali were a typical bimodal curve which were determinately regulated by non-stomatal inhibition. On cloudy day, diurnal changes in net photosynthetic rate(Pn) showed single-peaked, photosynthetic active radiation and humidity were the main factors. The "midday rest" of Whangkeumbae was more significant than that of Yali.2. Seasonal changes in net photosynthetic rate (Pn) in Whangkeumbae and yali were a typical bimodal curve which was determinately regulated by stomatal conductance, intercellular CO2 concentration,chlorophy11 content etal physiol factors.3. For Whangkeumbae researched,the light compensation points were at 43μmol·m·-2·s-1, light saturation points at 1042μmol·m-2·s-1; The CO2 compensation points were at 52μl·L-1, and the CO2 saturation points at 1483μl·L-1; the light compensation points of yali were at 53μmol·m-2·s-1, light saturation points at 1873μmol·mol·m-2·s-1; The CO2 compensation points were at 54μl·L-1, and the CO2 saturation points at 1382μl·L-1, The capacity of use low light, carboxylation efficiency, RuBP regeneration velocity and photosynthesis capability were stronger than that of Yali.