Intergenic spacer 1 (IGS1) polymorphism map: A marker for the initial classification of cultivated Lentinula edodes strains in China

Abstract China is currently the world's leading producer of Lentinula edodes and owns many cultivated strains of this species. This study was performed in order to investigate intergenic spacer 1 (IGS1) polymorphism and classification among 49 popular cultivated strains. The great majority of the 49 strains possessed two different IGS1 sequences, with distinct lengths and homologies. Based on the length and homology of the IGS1 sequences of the 49 strains, the strains were classified into two groups: A and B. Group A was subdivided into six subgroups. Forty-seven strains were homozygous or heterozygous among these six subgroups in group A, Cr01 was heterozygous between A and B, and Guangxiang 9 was homozygous in group B. An IGS1 polymorphism map of each cultivated L. edodes strain is reported for the first time and could be used as a marker for the initial classification and management of cultivated L. edodes strains in China.