Effect of Low Potassium Stress on the Photosynthetic Characteristics of Different Rice Genotypes

Two low potassium(K) tolerance rice(Oryza sotiva L.)genotype,N18 and N19,and their recipient,N27(control) were used to investigate the effects of low K stress on the photosynthetic characteristics of different rice genotypes at seedling stage.The results showed that under low K stress condition,although the contents of chlorophyll a,chlorophyll b and chlorophyll(a+b) in leaves of all genotypes decreased,the contents of them were higher in N18 and N19 than that in N27.Also although the net photosynthetic rate,respiration rate,stomatic conductance,intercellular CO2 concentration and transpiration rate of leaves of all genotypes stressed by low K decreased,the reduction degree in N18 and N19 were less than that in N27.