Heat resistance in the mycelial stage of Stropharia rugosoannulata and response of antioxidant enzymes to high temperature
One hundred hybrid strains selected by monospore crossbreeding of Stropharia rugosoannulata were used as test materials.By observing the mycelial recovery growth of each strain after high temperature stress,seventeen hybrid strains were screened with stronger heat tolerance than parents in mycelial stage.After eight hours of high temperature stress at 44℃,these strains could survive,while both parents were dead.Among them,four hybrid strains(QM2,QM15,QM46,and QM83)had stronger heat tolerance and could survive after eight hours of high temperature stress at 46℃.The hybrid strain QM15 with strong heat resistance and hybrid strain QM27 with poor heat resistance were used as test materials to determine the dynamic changes of antioxidant physiological indexes related to heat resistance in the mycelial stage,including superoxide dismutase(SOD),peroxidase(POD),catalase(CAT)and malondialdehyde(MDA).The results showed that under high temperature stress the activities of CAT and SOD of the two strains in the mycelial stage increased first and then decreased.The POD activity of strain QM27 increased first and then decreased,while that of strain QM15 with strong heat resistance recovered the level prior to stress treatment after six hours of high temperature stress at 44℃,and the activity increased slightly after eight hour stress.The activities of three enzymes of strain QM15 were always higher than those of QM27.The results indicate that strain QM15 with strong heat resistance has stronger antioxidant capacity and can mitigate membrane damage under high temperature stress.The changes of activities of the three antioxidant enzymes under high temperature stress can be used as physiological indexes for identification of heat resistance in the mycelial stage of Stropharia rugosoannulata strains.
Stropharia rugosoannulatahybrid strainsheat resistancehigh temperature stressantioxidant enzymes
万方数据
维普
