Comparison of drought resistance of wild Leymus secalinus and Elymus nutans in Tibet

Drought is one of the most important factors restricting the growth and development of grasslands in Tibet. To counter these effects, we studied drought resistance ability in two species of wild forage plant, by collecting seeds of Leymus secalinus and Elymus nutans in Tibet, in order to provide reference for the ecological restoration of arid and semi-arid areas, and selection of grass species in artificial grassland. The results showed that the growth rate, plant water content, and chlorophyll content of two wild forage species decreased with the increase of drought time, and the difference was significant (P<0.05). The contents of malondialdehyde and free proline increased with increase in drought time, and the difference was significant (P<0.05). Soluble sugar content of L. massoniana decreased first and then increased, while the soluble sugar content of E. nutans decreased first and then increased, and finally decreased. The soluble protein content decreased first and then increased. The two biological characteristics and the five physiological characteristic indexes of the two wild forage species were comprehensively evaluated by the membership function method, and the drought resistance of L. secalinus was greater than that of E. nutans.