Effect of exogenous salicylic acid on seed germination and seedling physiological characteristics of kidney bean(Phaseolus vulgaris L.) under salt stress

The research was carried out to study the effects of exogenous salicylic acid(SA) on seed germination and seedling physiological characteristics of kidney bean(Phaseolus vulgaris L.)under salt stress. Different concentrations of SA solution were used in NaCl- salt stressed seeds of kidney bean. Seed germination index, seedling growth index and physiological index were measured.The results showed that 7 g· L- 1NaCl significantly reduced the germination potential, germination rate and germination index of kidney bean seeds, the root length and stem length of kidney bean seedling,and also the SOD activity, but improved seedlings MDA content. Under salt stress, along with the increasing of the SA concentration, the germination potential, germination rate, germination index,seedling's main root length, shoot length, lateral root number and SOD activity showed the trend of increase first and then decrease with the peak at 0.5 g · L- 1SA, but the MDA content of seedlings decreased first and then increased with the lowest at 0.5 g· L-1SA. NaCl salt stress depressed the seed germination and seedling growth of kidney bean, and SA could alleviate salt stress, and 0.5 g· L- 1SA was the best concentration.