Mating type-correlated molecular markers and demonstration of heterokaryosis in the phytopathogenic fungus Thanatephorus cucumeris (Rhizoctonia solani) AG 1-IC by AFLP DNA fingerprinting analysis.
The destructive soil-borne plant pathogenic basidiomycetous fungus Thanatephorus cucumeris (Frank) Donk [anamorph: Rhizoctonia solani Kühn] is not a homogeneous species, but is composed of at least twelve anastomosis groups (AG), which seem to be genetically isolated. The genetics of several T. cucumeris anastomosis groups has been studied by analysis of heterokaryotic tuft formation in the area of contact between homokaryotic single-spore isolates, revealing that AG 1 is heterokaryotic and bipolar. To prove that tuft formation is due to heterokaryosis, AFLP DNA fingerprinting has been applied to a heterokaryotic T. cucumeris AG 1-IC isolate, its homokaryotic single spore-derived progeny, and newly formed heterokaryons. By means of AFLP markers, it is demonstrated that fluffy tufts formed upon pairing of homokaryons from different mating types are newly formed heterokaryons. Mating type-correlated markers have also been found, which will be useful for future studies of the genetics of this fungal species complex.
Julián
M C
MC
Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología (CSIC-UAM), Universidad Autónoma de Madrid, Spain. mjulian@cnb.uam.es
Acero
J
J
Salazar
O
O
Keijer
J
J
Rubio
V
V
D016172:DNA Fingerprinting / Q000379:methods*; D004271:DNA, Fungal / Q000032:analysis*; D005800:Genes, Fungal; D049770:Genes, Mating Type, Fungal; D005819:Genetic Markers; D006579:Heterozygote; D015203:Reproducibility of Results; D012232:Rhizoctonia / Q000235:genetics*; D013172:Spores, Fungal / Q000235:genetics