Effects of salt stress on the physiological characteristics of Solanum photeinocarpum

A pot experiment was used to study the effects of different concentrations of salt (100, 200, 300 mmol/L) stress on the photosynthetic physiology and antioxidant enzyme activities of Solanum photeinocarpum . The results showed that NaCl of 100 and 200 mmol/L could significantly improve the contents of chlorophyll a , chlorophyll b and carotenoid in S. photeinocarpum . However, under different concentrations of salt stress, there was no significant difference in the amount of total chlorophyll in S. photeinocarpum . Besides, as the salt stress increased, the net photosynthetic rate, stomatal conductance, CO2 concentration of intercellular and transpiration rate of S. photeinocarpum gradually decreased, when the concentration of NaCl was 300 mmol/L, reached the lowest value. With the increase of salt stress, the POD activity, CAT activity and soluble sugar content of S. photeinocarpum increased first and then decreased, reaching the highest when the concentration of NaCl was 100 mmol/L. Therefore, S. photeinocarpum had a certain salt tolerance, low concentration of NaCl (≤ 200 mmol/L) stress could promote its growth, but high concentration (> 200 mmol/L) could inhibit its growth.