Photosynthetic Characteristic of Three Varieties of Lilium(Liliaceae)"Oriental Hybrids" in the Middle of Yunnan Province

To understand the ecophysiological adaptation of Lilium Oriental Hybrids which was grown for the commercial bulb,the gas exchange,leaf N and chlorophyll content of three varieties were investigated in the middle of Yunnan province.Among three varieties,light saturated photosynthetic rate at ambient CO2(Amax)of Siberia was the highest,while Siberia(was the lowest.The difference in Amax was related to the carboxylation efficiency(CE),leaf mass per unit area and leaf N content per mass,which indicated that their photosynthetic capacity was influenced by the activity and/or the number of Rubisco.Three varieties had lower photosynthetic saturation point and photosynthetic compensation point,but their photosynthetic rate not decreased up to 2 000 μmol m-2s-1.This indicated that three varieties had broad adaptability to light intensity.There were significant differences in photosynthetic optimum temperature among three varieties.However,the variety Siberia had the highest photosynthetic optimum temperature(25.5℃-34.9℃),and it was suitable to grow in the warm area.Sorbonne had the lowest photosynthetic optimum temperature(19.3℃-25.6℃),and it can be grown in the cool area.Tiber could maintain high photosynthetic rate at a wide range of temperature,so it was more suitable for the climate in the middle of Yunnan province.