LAUSR

Abstract Elymus nutans Griseb. was planted in three locations on Qinghai-Tibetan Plateau of China to test if geographic differences would impact fatty acid (FA) and amino acid (AA) metabolism. It was found that lipid and crude protein content of E. nutans differed among locations, both highest in Haibei (HB) and lowest in Aba (AB). Significant difference on the amount of FAs and AAs was found among locations, both highest in HB and lowest in AB. The same change was found in unsaturated FA (UFA) and essential AA. Therein, the ratio of UFA to saturated FA varied from 1.44 to 2.01, and the amount of UFA was highest in HB, which concluded that low temperature and less precipitation could accumulate more UFA in E. nutans; It is interesting that the ratio of essential AA to non-essential AA varied from 0.53 to 0.56. This study reveals that the contents of FA and AA content are more influenced by environments, while AA composition is mainly determined by genotype.