Physiological Response To Salt Stress And Growth And Development Of Glycine Soja

Wild soybean (Glycine soja Sieb.et Zucc.) is an annual legume species, which is one of the plant species mainly protected in China. The salt resistance, disease resistance, insect resistance, reproductive unisolation with cultivated soybeans and other good qualities are benefit to culture in soybeans. In this paper, the growth period and dynamic growth regularity were studied. The effective methods of breaking hard seeds of wild soybean were selected. In different growth stages, the responses of wild soybean under different salt tolerance were tested. This article provides the important theoretical basis for improving salt-resisting gene of soybean, and the research was the important theory foundation for the future studies, researches and utilization of wild soybean.The results are as follows. Surveys of the growth period showed that the growth and development period of wild soybean was 150 d, including vegetative stage about 70 d. and reproductive stage about 59 d. Vegetative growth had been to mature stage, in which the height, fresh weight, stem diameter was increasing, the leaf area growed gradually before the flowering stage and there was almost no change after flowering period. Water content of their organizations was coming down during all the growth periods. The nodules reached the maximum at flowering period.Soaking in concentrated sulfuric acid, hotwater immersion, gringing were used to damage seed coat. The result showed that the three ways can significantly increase seed germination rate, and concentrated sulfuric acid method is the best.Treated with different concentrations of NaCl,KCl,Na2SO4,K2SO4,Na2CO3,NaHCO3 stress of wild soybean seeds, the results showed that the inhibition to seed germination ability was obvious in Na2CO3 and NaHCO3 intermediate in Na2SO4,K2SO4, the lowest in NaCl and KCl. The low concentrations of neutral salt stimulated the germination of wild soybean seeds. The alkaline salts did not show synergistic effects on seed germination. Higher concentration of salt stress inhibited the seed germination.While two true leaves fully expanded, wild soybean seedlings were transferred to different concentrations of NaCl. and cultured in the solution for 12 d. The results showed that there was no significant effect on the growth of wild soybean under low concentration of NaCl. While under severe stress or time prolonging, the growth rate of fresh weight was slower, water content ratio reduced, root-shoot ratio increased, the content of soluble sugar increased quickly but it decreased a little later, the content of soluble protein increased at first and then decreased, the content of Pro and MDA constant increased. The results indicated that the wild soybean had certain of salt tolerance. Through the variation of root-shoot ratio, water content ratio, the content of soluble sugar, soluble protein, MDA and Pro, the important strain indices were reflected in the salt tolerance of wild soybean.The wild soybeans were irrigated with NaCl solution, using the soil as the substrate. The rehydration treatment were done after the salt stress culture lasted for five weeks. The results showed that the variation of agronomic characters was similar to that in seeding under salt stress. The changing regularity of the soluble sugar, soluble protein and MDA was consistent with that in seeding. In contrast, the content of Pro and chlorophyll increased first and decreased later following with the increasing salt stress. All of the indexes become normal after rehydration treatment...