Effect of Different Nitrogen, Potassium Levels on Photosynthesis in Flue cured Tobacco

Photosynthesis of flue cured tobacco (Nicotiana tabacum L cv NC89) under different nitrogen, potassium levels was studied The results suggested that under high nitrogen, potassium levels the photosynthetic oxygen evolution rate, photosynthetic electron transport activity ,RuBP carboxylase (RuBPCase) and carbonic anhydrase (CA) activities in tobacco leaves were significantly increased,and the significant change of chlorophyll content wasn't observed Under low nitrogen, potassium levels,the photosynthetic oxygen evolution rate,chlorophyll content,photosynthetic electron transport activity and RuBPCase activity were markedly decreased,while the CA activity was slightly decreased compared with the check In contrast to nitrogen, the effect of potassium on photosynthesis in tobacco leaves was more significant