title: Molecular Markers to Detect the Formation of Heterokaryon and Homokaryon from Asexual Spores of the Caterpillar Medicinal Mushroom, Cordyceps militaris (Ascomycetes).
abstract: Cordyceps militaris is widely cultivated on artificial media in China; however, the cultures often are afflicted with the degeneration of nonfruiting strains. To understand the mechanism of degeneration of C. militaris, from the heterokaryotic strain into the homokaryotic strain, we examined the mating-type genes present in individual asexual spores. Further, we determined the distribution ratio of the different mating-type genes among a sample of asexual spores and the growth rate of heterokaryotic and homokaryotic strains of C. militaris. The distribution ratio of 3 groups of asexual spores from C. militaris heterokaryotic strains was determined as 1:1:1 by statistical analysis, whereas that of the two types of nuclei among asexual spores was 1:1. Nearly two-thirds of the asexual spore isolates were homokaryon, which showed a growth speed similar to the heterokaryon. However, the homokaryon (bearing mating-type MAT-HMG) grew significantly faster at times compared with the heterokaryon. Therefore, the purity of the spawn was difficult to establish. C. militaris heterokaryotic strains can transform into a homokaryotic strain following continued subculture.
authors.affiliation: Key Laboratory of Applied Mycological Resources and Utilization, Ministry of Agriculture, People's Republic of China, and the Shanghai Biotechnology and Engineering Research Center for the Edible Fungi, Shanghai Key Laboratory of Agricultural Genetics and Breeding, Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai, People's Republic of China.
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.affiliation: Key Laboratory of Applied Mycological Resources and Utilization, Ministry of Agriculture, People's Republic of China, and the Shanghai Biotechnology and Engineering Research Center for the Edible Fungi, Shanghai Key Laboratory of Agricultural Genetics and Breeding, Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai, People's Republic of China.
authors.forename: Tao
authors.initials: T
authors.lastname: Cai
authors.affiliation: Key Laboratory of Applied Mycological Resources and Utilization, Ministry of Agriculture, People's Republic of China, and the Shanghai Biotechnology and Engineering Research Center for the Edible Fungi, Shanghai Key Laboratory of Agricultural Genetics and Breeding, Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai, People's Republic of China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wei
authors.affiliation: Key Laboratory of Applied Mycological Resources and Utilization, Ministry of Agriculture, People's Republic of China, and the Shanghai Biotechnology and Engineering Research Center for the Edible Fungi, Shanghai Key Laboratory of Agricultural Genetics and Breeding, Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai, People's Republic of China.
authors.forename: Aiping
authors.initials: A
authors.lastname: Feng
authors.affiliation: Key Laboratory of Applied Mycological Resources and Utilization, Ministry of Agriculture, People's Republic of China, and the Shanghai Biotechnology and Engineering Research Center for the Edible Fungi, Shanghai Key Laboratory of Agricultural Genetics and Breeding, Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai, People's Republic of China.
authors.forename: Nan
authors.initials: N
authors.lastname: Lin
authors.affiliation: Key Laboratory of Applied Mycological Resources and Utilization, Ministry of Agriculture, People's Republic of China, and the Shanghai Biotechnology and Engineering Research Center for the Edible Fungi, Shanghai Key Laboratory of Agricultural Genetics and Breeding, Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai, People's Republic of China.
authors.forename: Dapeng
authors.initials: D
authors.lastname: Bao
mesh_terms: D000363:Agaricales; D000383:Agriculture; D002681:China; D032661:Cordyceps / Q000235:genetics* / Q000254:growth & development; D049770:Genes, Mating Type, Fungal; D013172:Spores, Fungal / Q000254:growth & development*