Comprehensive Evaluation of Shiitake Strains (Lentinus edodes, Agaricomycetes) Based on Polysaccharide Content and Agronomic Traits.

Abstract

Polysaccharides are some of the most important bioactive compounds in Lentinus edodes, but little attention has been devoted to the genetic basis of polysaccharide content. Here, the polysaccharide content of fruiting body, and 11 agronomic traits related to morphologic characteristics of fruiting body, yield and precocity of 50 L. edodes strains were screened and analyzed. Results showed that polysaccharide content in L. edodes fruiting bodies is a quantitative trait controlled by the polygenic system. Several wild strains possess desirable polysaccharide contents, exhibiting the potential to improve shiitake cultivars by introducing the promising alleles. There were no close correlations between polysaccharide content and the 11 agronomic traits related with fruiting body morphology, yield and precocity, suggesting that polysaccharide content and the development of fruiting bodies may genetically be controlled independently. Moreover, based on polysaccharide content and the 11 agronomic traits, grey relational analysis (GRA) was employed for a comprehensive strain evaluation by calculating grey relational grades. The results demonstrate that weighted relational grade analysis is effective in the comprehensive evaluation of L. edodes strains. The ranking of most cultivars was higher than that of wild strains. Cultivar ZP9 was the best strain, concerning its comprehensive phenotypic performance. Wild strain YS1 with the highest polysaccharide content (6.60%) also ranked in the top seven. In our study, we developed the first multiple-trait strategy for L. edodes strain evaluation. The step-by-step procedures of GRA described here provide an important reference for strain evaluation and selection of other edible mushrooms.