Heat Stress Response Of Different Edible Mushroom Germplasms

In China,production of edible mushroom by traditional agricultural facilitiesis extremely sensitive to temperature alterations induced by climate changes.High temperature stress induces reduced growth rate and leads to decreased quality and yield of edible mushroom.In this study,we analyzed the physiological response of Pleurotus to heat stress,and examined the influence of heat stress on the metabolism of trehalose.After recovery post high temperature stress,the development and growth of Pleurotus eryngii var.tuoliensis and Pleurotus eryngii displayed significantly decrease.Remarkably,the mycelium branching frequency among different strains exhibited highest variations,and the strain with relatively stable mycelium branching frequency harbored stronger heat tolerance.High temperature stress was found to negatively contribute to the tolerance on Trichoderma asperellum infection.In addition,the growth rate and the tolerance of T.asperellum infection exhibited negative correlation fashion.We found that the way of inoculation may affect T.asperellum infection rate.Mushroom bags with fully grown mycelium were 100%sensitive to T.asperellum mycelium infection and 30%sensitive to T.asperellum spore infection,respectively.Under heat stress,accumulation of trehalose and the activities of corresponding TPS enzymes displayed significant correlation between the heat-sensitive and heat-less-sensitive Pleurotus pulmonarius strains,and the correlation ratio was 0.942 and 0.872,respectively.These findings suggest that TPS-TPP pathway may play a role in the heat resistance of P.pulmonarius.Proper treatment with exogenous trehalose promotes heat tolerance by reducing peroxidation of lipid membrane and by promoting endogenous trehalose accumulation;and these effect is more stronger on the heat-sensitive strain.Under heat stress,higher level of trehalose was observed in the heat-sensitive strain,suggesting trehalose may positively contribute to heat tolerance of P.pulmonarius.However,the endogenous trehalose status may be not correlated with heat sensitivity.