Plain Leymus Chinensis Populations Of Two Habitats Rhizome Soluble Carbohydrate Content Dynamically

Water-soluble carbohydrate plays an important role in metabolism of the plant. The rhizome of Leymus chinensis is not only the important organ of vegetative reproduction, but also the important storage organ.The contents of water-soluble carbohydrate of the rhizome of Leymus chinensis in two inhabits of sand soil and saline soil during the different development stages were studied on the Songnen Plain of China. The results showed that:(1) The contents of water-soluble carbohydrate of rhizome in two inhabits changed similarly and regularly from the flowering stage to the end of growth season. From the flowering stage to the dough ripe stage, the contents of water-soluble carbohydrate increased, while were the lowest values at the beginning of the stage after fruiting, and reached the highest values at the end of the growing season.(2) The contents of water-soluble carbohydrate of rhizome at different development stages in the inhabits of sand soil and saline soil decreased with the ages increasing, and the order was 1a﹥2a﹥3a. The difference of the content of water-soluble carbohydrate between the different age classes of the rhizomes in the inhabits of sand soil and saline soil during the different development stages reached the significant level(P≤0.05). Because the ages of rhizome were divided according to actual living years, the trend of decreasing of the contents of water-soluble carbohydrate of rhizome with the age increasing adequately showed the obvious difference of viability and fecundity of different ages of rhizome, which was a direct support for scientific method of division of age structure of Leymus chinensis population, a clonal population of rhizome type grass.(3) The bud of the rhizome apex is an important module for Leymus chinensis population in the process of vegetative propagation to expand eco-space. But the contents of water-soluble carbohydrate in the bud of the rhizome apex were not high except for the end of growth season, and even lower than that of the rhizome of the 3rd age class. (4) Except for the beginning of the stage after fruiting of sand soil, as for the absolute contents of water-soluble carbohydrate which were stored, the base stem was the most, the second was the rhizome, the least was the tillering node.(5) The variance analysis showed that the difference of the content of water-soluble carbohydrate between the rhizome node and the rhizome internode in the inhabits of sand soil and saline soil reached the significant level(P≤0.05)during the different development stages.(6) The variance analysis showed that the difference of the content of water-soluble carbohydrate between rhizome node and rhizome internode in the inhabits of sand soil and saline soil during the different development stages did not reach the significant level(P﹥0.05)except for the flowering stage.(7) The contents of water-soluble carbohydrate of budless node were higher than that of gemmate node.