Effects of cold stress on some antioxidant enzymes and physiological traits of oats in greenhouse

In order to evaluate the diversity of oat genotypes (Avena sativa L.) in response to cold stress, 21 oat genotypes were studied in the Faculty of Agricultural Sciences and Engineering of Razi University, Kermanshah in 2015-2016 under controlled conditions in the greenhouse. Two separate experiments were conducted to determine the 50% plant lethality temperature (LT50) and the effect of short-term cold stress on physiological characteristics and antioxidant enzymes, in the form of a completely randomized design. Variance analysis of LT50 showed that there is a significant genetic variation between the investigated genotypes in terms of LT50 level. The average of LT50 trait showed that the genotypes (Ozark), (UFRGSP 948886), (UPF775456), (Euro), (GA Mitchell), (Mortlock), (OH1022), (Brusher), (Wallaroo) and (Kalott) had the highest LT50 value and can be considered as cold tolerant genotypes, and (Quoll) and (Nasta) genotypes had the lowest values. A positive and significant correlation was observed between the catalase enzyme and chlorophyll content and between the peroxidase enzyme and ion leakage rate. The Ozark and UFRGS 948886 genotypes were placed in the group with the maximum mean LT50, chlorophyll content, carotenoid content, catalase enzyme, peroxidase enzyme and minimum ion leakage rate in the cluster analysis. Therefore, it could be stated that the genotypes of this group have better conditions in terms of cold tolerance than other genotypes.