The Population Genetic Characteristics Of Elymus Nutans Griseb. Under Different Grazing Intensity

The reasonable utilization of grassland is not only benefit for the persistent development of animal husbandry, but also benefit for ecological balance. However, for the past few years, because of the excessive utilization of grassland, our nation has became one of the most serious grassland degradation nations. Studies show that overgrazing is the primary reason of grassland degradation. Overgrazing can influence the grow of pasture, the plant community composition and soil characteristics. We detected 800 individuals of Elymus nutans Griseb. under different grazing intensity using SSR to analyses the genetic diversity, gene differentiation, gene flow and gene structure. Then we reveal the molecular mechanisms of consequence of Elymus nutans Griseb under different grazing intensity.The main findings and conclusions of this research as follows:For the pasture land, moderate grazing is the best one to maintain the gene diversity of Elymus nutans Griseb population. The gene diversity of the moderate grazing pop μ Lation is highest of the pastureland. The Elymus nutans Griseb population under on grazing also has high gene diversity.The gene differentiation between Elymus nutans Griseb populations is high, the gene flow between Elymus nutans Griseb populations is low. The consequence indicate that the possibility of gene exchange between different pop μ Lations is low, this may because the self-pollination of Elymus nutans Griseb and this result demonstrates that grazing has great influence on the population genetic diversity.