Effects of KNO_3,K_2SO_4 and Their Mixed Salt Stress on Plant Growth and Leaf Photosynthetic Characteristic of Pepper Seedling

The effects of KNO3,K2SO4 and their mixed salt stress(0,50,100,150,200 mmol/L)on plant growth and photosynthetic characters of pepper(Liangjian named)seedling were investigated.The results showed that plant height,root length,leaf numbers,accumulation of biomass production,the total Chl,Chla,Chlb,net photosynthetic rate,transpiration rate,stomatal conductance and water utility efficiency decreased gradually,and intercellular CO2 concentration increased gradually with increasing of salt concentration.The reduction of net photosynthetic rate under relatively lower salt treatment was the result of stomatal limitation,and non-stomatal limitation was the main reason for the decrease of net photosynthetic rate under higher salinity stress.K2SO4 salt hurt more important on pepper seedling LiangJian than KNO3 and their mixed salt(1∶ 1).