Nearly half of the land in Tibet is arid or semi-arid. Due to its special topographical, geomorphic and climatic conditions, the natural conditions are harsh, the ecosystem is fragile, and the carrying capacity is very limited (Sun et al., 2012; Zhang et al., 2015). Global climate change and the impact of human activities have further aggravated the situation in recent years, and grassland degradation has become one of the most serious ecological problems facing Tibet (Liu et al., 2012; Fu et al., 2018). In order to relieve the pressure of natural grassland and protect the ecological environment in Tibet, the vigorous promotion of human-made grassland has become a key measure (Gao et al., 2014; Duan et al., 2019). Pennisetum centrasiaticum Tzvel is a perennial forage of Pennisetum in Gramineae. P.centrasiaticum is widely distributed in arid and semi-arid areas of Tibet. Its rhizome system is developed and has strong resistance to adversity. It has genes to resist disease, insects, cold and drought that wheat crops lack. The biomass and nutritional quality of P.centrasiaticum are high at jointing stage (Li, 1983; Gao, 2008). PEG-6000 can simulate drought stress by regulating the osmotic pressure of solutions to limit water entering seeds, so the use of PEG-6000 offers a fast and reliable method to simulate a drought environment for the purpose of screening drought-resistant varieties (Hegarty, 1977; Van den et al, 2006). At present, there are few studies of P.centrasiaticum in Tibet. There is no data about the use of PEG-6000 to simulate a drought environment to screen out the P.centrasiaticum from different areas. The meteorological data from 1971 to 2014 showed that drought conditions in Tibet have worsened over the years, and this may cause devastating, long-term damage to the agriculture, economy and ecosystem of Tibet (Li et al., 2019). Seedling stage is the key stage of forage growth, and is sensitive to water response. Therefore, identifying varieties with strong drought resistance at seedling stage can be of significant value as a guide for production. Drought resistant forage types are key to the development of animal husbandry in Tibet (Cui et al., 2015).