Genetic Clarification of Auricularia heimuer Strains Bred and Cultivated in Korea Using the ITS and IGS1 rDNA Region Sequences

Abstract

Auricularia is one of the broadly cultivated edible mushrooms in Korea. Most of the Korean Auricularia strains used for cultivation and breeding are known as A. auricula-judae. Recently, this species has been reported to belong to a species complex. Therefore, this study was carried out to genetically clarify the bred and cultivated Korean A. auricula-judae strains. The internal transcribed spacer (ITS) and IGS1 rDNA region sequences were determined from 10 A. auricula-judae strains by PCR and sequencing. Variation in the nucleotide sequence and sequence length of the two rDNA regions were found among the seven A. auricula-judae strains. A maximum-likelihood (ML) phylogenetic tree based on the ITS sequences clearly placed all the 10 Korean A. auricula-judae strains in the A. heimuer clade of the A. auricula-judae complex. A. heimuer is diverged from A. auricula-judae. An ML phylogenetic tree based on the IGS1 sequences revealed the close relationship between Korean A. heimuer strains to Chinese A. heimuer strains. But each strain could be distinguishable by the IGS1 sequence. Furthermore, progeny strains in the seven Korean strains could be differentiated from their parental strains by the IGS1 sequence based phylogenetic tree. Our results are expected to be used to complement the distinction of domestic Auricularia cultivars.

Keywords:

• Auricularia heimuer
• A. auricula-judae complex
• ITS
• IGS1

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was supported by R&D Program for Forest Science Technology [Project No. FTIS 2020204A00-2121-BA01] provided by Korea Forest Service (Korea Forestry Promotion Institute) and Dankook University in 2022.