Comparison of chilling resistance of six Elymus germplasms

Low temperature is one of the important limiting factors affecting plant growth. The chilling resistances of six Elymus germplasms were evaluated, and, after 8, 16, and 24 days of chilling treatment (5 ℃), plants were harvested and their relative membrane permeability, relative water content, malondialdehyde (MDA) content, chlorophyll content, accumulation of osmotic regulation substances and antioxidant enzyme activities, and change rates (measured value under low temperature treatment/measured value under control) were analyzed and compared. The aim of this work was to explore the differences in cold resistance among the plant materials used, to provide a theoretical basis for the selection of Elymus lanceolata germplasm in alpine regions. The results showed that, in the process of low-temperature treatment for 24 days, all the six tested materials showed different degrees of cold adaptability. Through subordinate function analysis of the changes in relative plasmalemma permeability, relative water content, and MDA and chlorophyll content, it was found that 12-9-1, 11-6, and 09-214 which grow at high altitudes could maintain their water and chlorophyll content by maintaining low relative membrane permeabilities and high osmotic adjustment abilities under chilling stress to exhibit a stronger chilling resistance.