Research On Ion Homeostasis And Osmotic Adjustment Of Glycine Gracilis Seedlings Under Different Types Of Saline Stresses

The semi-wild soybean (Glycine gracilis) is a hybrid type of cultivated soybeanand wild soybean.Given high resistance of the wild soybean and high yield of thecultivated soybean, so semi-wild soybean has high research value. Semi-wild soybean(G. gracilis) was chosen as our experimental materials. Two neutral salts were mixedat a1:1molar ratio of NaCl: Na2SO4and applied to the saline stress group. Similarly,two alkaline salts were mixed at a1:1molar ratio of NaHCO3to Na2CO3and appliedto the alkaline stress group. Five different concentrations (15,30,60,90,120mmol·L-1) of saline and alkaline stresses were designed to treat the six weeks old G.gracilis seedlings for six days. The threat change indicators including length of root,shoot height, relative growth rate, water content, inorganic ions, organic solutes andinorganic ions, organic solutes distribution in roots, stems, leaves were determined toexplore and compare characteristics of saline and alkaline stress acting on G. gracilisand the responses of G.gracilis to them from growth, ion transport, osmoticadjustment and ion toxicity and so on.The main results and conclusions were as follows.The injury effect of alkalinestress on G. racilis was stronger than saline stress. The effects of saline stress on theroot length, shoot height and relative growth rate were much less than those ofalkaline stress. The mechanisms governing ionic balance under both stresses weredifferent. Under saline stress, proline, sucrose and fructose content does not changesignificantly. However, under alkaline stress, roots, stems, petiole and proline contentincreased, sucrose, fructose content decreased; The leaf proline, sucrose, fructosecontent increased. This should be saline stress, semi-wild soybean different responsemechanism performance. In conclusion, saline and alkaline conditions are twodifferent stress conditions and there are special.