Phenotypic evaluation and analysis of important agronomic traits in the hybrid and natural populations of Lentinula edodes

• Comprehensive variability was observed in the natural germplasm of Lentinula edodes.
• Wild strains have the potentiality for shiitake breeding.
• The correlations between pairs of agronomic traits were investigated.
• The number of fruiting bodies is the key component influencing yield in the populations examined.

Several important agronomic traits of shiitake strains in two hybrid populations and a natural population were evaluated through three independent fruiting trials. The correlations among the agronomic traits of shiitake were also analyzed using multivariate statistical methods. Results showed that wild shiitake strains in the natural population had a wider range of phenotypic variation than those in the two hybrid populations. Interestingly, several strains with superior phenotypes related to precocity and increasing number of fruiting bodies were found in the natural population. Then, factor analysis indicated that the three major factors (single fruiting body, yield and precocity) accounted for over 80% of the total variance. To further examine relative contributions of yield-component traits (the number of fruiting bodies and the weight of single fruiting body) to yield through path analysis, our results demonstrated that the number of fruiting bodies was the key component influencing yield. This is the first report on the phenotypic analysis of yield and other agronomic traits using multiple populations in shiitake. Our study not only advances the knowledge of correlations between agronomic traits, especially between yield and yield-component traits, but also provides useful information for utilizing valuable natural resources to develop high-yield shiitake cultivars in future.