Physiological and Biochemical Characteristics and RAPD Analysis of the Aging Soybean Seed
|Keywords||soybean aging physiology and biochemistry RAPD analysis|
By the comparison of some physiological and biochemical indexes, the carbohydrate content, membrane lipid acids and RAPD analysis of the natural and artificial aged soybean seeds, the experimen discusses regulation among them and provided some theoretical basis and reference for the mechanism of seed aging.The results are as follows.1. By measuring some physiological and biochemical indexes of the natural aged soybean, the results show that with increasing of the storage time, deepening of aging of soybean seeds, the germination energy, germination percentage, germination index and vigor index show a down trend, and vigor index decline quickiy; the conductance and the soluble sugar of the soaking gradually increase; MDA content in radicals also increase; SOD, POD, CAT and the fat hydrolyze activity decrease, the POD activity of which is the most significant, and the enzyme electrophoresis patterns gradually dim or disappear.2. With storage period increased, the changes of the carbohydrate content in the radicals and cotyledons of the aged soybean are as follow. The monosaccharide (galactose, inositol) content do no change much in the radicals of the natural aged soybean, the sucrose content declined in the overall; the monosaccharide content of the cotyledons show a slight increase, the sucrose content firstly increase and decreased, the melibiose content have the slight increase. The galactose, inositol, sucrose and melibiose content have the different level’s lower, and the sucrose content fall quickly. In addition to the melibiose content decreased, the others have a litte change. Overall, the range of the carbohydrate contents changes in the radicals of the artificial aged soybean are bigger than that of the carbohydrate, but less than the ones which are in the radicals of the natural aged soybean.3. With the storage time going on, the deepening of aging. The trend of palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid content are the same, the ratio of the unsaturated and saturated fatty acid increase, and the significant trend are the proportion of linoleic acid increased, linolenic acid decreased among the fatty acids change. The five kinds of fatty acids’content show a low trend. The five kinds of the fatty acids changes are almost the same, which show a decline trend. The ratio of the unsaturated and saturated fatty acid decreases. And the proportion of palmitic and stearic acid increase.4. The RAPD analysis of the genome DNA of the aged soybean obtained the genetic identity decreased with the aging time going on, the percent of the polymorphic bands in the radical of the natural aged is smaller than in the cotyledons, but bigger than that of the radical of the artificial aged seeds. The genetic identity between the aged seeds declines with the aging time prolonged. The range and average of the genetic identity in the radical of the natural aged seeds are greater than the ones which of artificial aged seeds.