Search

Heat stress is one of the major abiotic stresses that adversely affect growth and yield in Lentinula edodes (Shiitake mushroom) under natural cultivation. In this study, two parental strains (L808 and Lsm9), an F1 strain, and an F2 population derived from their hybrid progeny were used to evaluate the regeneration of mycelia after heat stress. A multi-level heat stress experiment showed that the dynamics of radial mycelium expansion of the two parents followed a linear equation after heat stress treatment at 37°C for 4–24 h, 42°C for 4–16 h, or 45°C for 4 h. Three indices were selected to describe the regeneration ability of the strains, including the number of regeneration days (NRD), the real growth rate after heat stress (Vregeneration), and the regenerative index (RI). L808 presented a faster rate of regeneration, while Lsm9 had better regeneration quality. The phenotype analysis of the F2 population showed that these indices were controlled by multiple genetic factors with high heritability. Four strains were selected from the population, pyramiding the advantages of heat resistance from the two parents. The results will help our understanding of the genetic features of this mushroom after extreme high-temperature stress.