We studied the effects of exogenous MeJA on the activities of superoxide dismutase（SOD）， peroxidase（POD） and ascorbic acid peroxidase（APX） of Pinellia ternata under high temperature stress， effects on proline（Pro）， malondialdehyde（MDA）， soluble sugar content and active ingredient content， and the effect on the expression of stress-related genes such as small molecule heat shock protein（sHSP）. The P.ternata plants with consistent growth status were subjected to stress treatment at 40℃， the experimental group was sprayed with 50 μmol/L exogenous MeJA solution， and the blank group was sprayed with the same amount of water. Samples were taken at 2， 6， 12， 24 and 48 h of treatment， respectively， and the indexes of the samples were determined. The results showed that spraying exogenous MeJA at a certain concentration at 40℃ could improve SOD， POD and APX activities of P.ternata leaves， reduce MDA content and increase proline and soluble sugar content. There was no obvious effect on the organic acid content of P.ternate. The expression levels of 2 cytoplasmic small molecule heat shock proteins and GRRBP proteins increased significantly after MeJA treatment. Therefore， spraying exogenous MeJA can partially enhance the activity of antioxidant enzymes in P. ternate， protect the cell membrane of P. ternate， and enhance the osmotic adjustment ability of cells. Moreover， exogenous MeJA may increase the expression of P. ternate high temperature stress response genes.
%U https://bbr.nefu.edu.cn/EN/10.7525/j.issn.1673-5102.2021.01.009