Responses Of The Seedlings Of Gleditsia Sinensis Lam. To Salt, Drought And Their Intercross Stresses

The growth, physiological and biochemical indexes of one-year-old seedlings of Gleditsia sinensis Lam. were tested to study their responses to salt and drought stress and their responses to the intercross stress of salt and drought were also studied. The main results are as the followings:The height growth of seedlings was inhibited and the biomass was decreased under the salt, drought and intercross stress conditions. Under different stress level, the ratio of root to comb was increased significantly; the distribution of more substance to root may be the main way of Gleditsia sinensis Lam. to adapt itself to adverse circumstance.The stomata inhibition was the major limiting factor of photosynthesis of Gleditsia sinensis Lam under 2‰,4‰salt stress and light drought stress; meanwhile the non-stomata inhibition was the major limiting factor of photosynthesis of Gleditsia sinensis Lam under 6‰salt stress, and the moderate and severe drought stresses. Under the intercross of salt and drought, T1B, T1C stresses were stomata inhibition types and other stress levels were non- stomata inhibition types.The changing trends of the contents of chlorophyll and the ratio of chlorophyll a/b were decreasing under salt and drought stress, chla was more sensitive to salt and drought than chlb. Under the intercross of salt and drought, the changing trends of the contents of chlorophyll and the ratio of chlorophyll a/b were more complicated and there were no regularity. 2‰,4‰salt stress, drought stress and the intercross stress of salt and drought increased the production of carotenoids.Under the salt and drought stress and the intercross stress of salt and drought, the membrane and MDA contents of Gleditsia sinensis Lam were...