Characterization of mating-type loci in rice false smut fungus Villosiclava virens
- Yu, Jun-jie [ Institute of Plant protection, Jiangsu Academy of Agricultural Sciences ]
- Sun, Wen-xian [ College of Agriculture and Biotechnology, China Agricultural University ]
- Yu, Mina [ Institute of Plant protection, Jiangsu Academy of Agricultural Sciences ]
- Yin, Xiao-le [ Institute of Plant protection, Jiangsu Academy of Agricultural Sciences ]
- Meng, Xiang-kun [ Institute of Plant protection, Jiangsu Academy of Agricultural Sciences ]
- Zhao, Jie [ Institute of Plant protection, Jiangsu Academy of Agricultural Sciences ]
- Huang, Lei [ Institute of Plant protection, Jiangsu Academy of Agricultural Sciences ]
- Huang, Li [ Montana State University: Plant Sciences & Plant Pathology ]
- Liu, Yongeng [ Institute of Plant protection, Jiangsu Academy of Agricultural Sciences ]
Ascospores of Villosiclava virens are a primary infection source of rice false smut. This phytopathogenic fungus exists in heterothallic form, and mating compatibility is regulated by mating-type locus 1 (MAT1). However, the MAT1 locus structure remains unknown. The MAT1-1 and MAT1-2 idiomorphs of V. virens were characterized and annotated on the basis of cDNA sequencing. A multiplex polymerase chain reaction (PCR) method was developed to identify the mating types of hyphae and sclerotia. The MAT1-1 locus of V. virens contains three mating-type genes: MAT1-1-1, MAT1-1-2, and MAT1-1-3, and a pseudogene similar to MAT1-2-1. The MAT1-2 locus harbors the MAT1-2-1 gene and a new mating-type gene MAT1-2-8. The mRNA of MAT1-1-1, MAT1-1-3, and MAT1-2-1, but not MAT1-1-2, was detectible by reverse transcription PCR (RT-PCR) in vegetative mycelia. However, the mRNA of MAT1-1-2 was detectible in the stroma, which is a sexual reproduction structure of V. virens. A multiplex PCR detection method was developed for the identification of the MAT1-1 and MAT1-2 idiomorphs. All 20 wild-type strains harbored either the MAT1-1 or MAT1-2 idiomorphs. Sclerotia that harbored both the MAT1-1 and MAT1-2 idiomorphs had potential to form fertile stromata, whereas those that harbored only the MAT1-1 idiomorph could not form mature stromata.