Objective: Evaluate the photosynthesis characteristics of Coptis chinensis and provide theoretical basis for the optimization of Coptis chinensis germplasm resources and variety.
Methods: The daily variation of the net photosynthetic rate, transpiration rate, stomatal conductance and intercellular CO2 density in leaf blade were determined by Photosynthesis analyzer, and the net photosynthesis rate of Coptis chinensis from different plant ages, types and production places was compared.
Results: The light saturation point in Coptis chinensis was about 500 micromol/m2 x s, light compensation point was about 12.04 micromol/(m2 x s), apparent quantum yield was 0.011. When the temperature was above 33 degrees C, the transpiration rate increased but the net photosynthesis rate decreased. There was no significant difference (P > 0.05) among the net photosynthesis rate of Coptis chinensis from different plant ages. The net photosynthesis rate of the type DA-YE and ZHI-HUA was significantly higher than that of other types (P < 0.05); The net photosynthesis rates of specimens from Fubao mountain in Lichuan county of Hubei and Fengmu village in Shizhu county of Chongqing were significantly higher than that of others.
Conclusions: The net photosynthesis rate of Coptis chinensis decreased under hight temperation and hight light. Different germplasm resources of Coptis chinensis, the net photosynthetic rate had certain differences.