Effects of exogenous IAA on the growth and physiological characteristics of Chinese cabbage seedlings under salt stress

A pot experiment was conducted to study the effects of the growth and physiological characteristics by spraying 5 different concentrations (0, 50, 100, 150, 200 mu mol/L) of indoleacetic acid (IAA) on leaves in Chinese cabbage seedlings which under salt stress. The result showed that IAA significantly promoted the growth and increased the biomass of Chinese cabbage seedlings under salt stress. It also enhanced the capacity of osmotic adjustment and antioxidant capacity, protecting the structure and function of cell membrane. Therefore, IAA can alleviate the damage of Chinese cabbage seedlings under salt stress, and the most suitable concentration is 150 mu mol/L. The seedlings which spraying 150 mu mol/L exogenous IAA compared with the control, the fresh weight of aerial part increased by 19.82%, the total dry weight increased by18.74%, CAT enzyme activities increased by45.66%, the chlorophyll content improved by 29.49%.