Heterothallic mating observed between Mexican isolates of Glomerella lindemuthiana.
Although several reports have described the occurrence of the teleomorphic state of Glomerella lindemuthiana (anamorph, Colletotrichum lindemuthianum), there has been a lack of continuity in this research. To identify G. lindemuthiana isolates capable of developing the teleomorphic state, 19 Mexican isolates were analyzed. Three types of response were observed: (i) negative, where only mycelial growth with or without acervuli was observed; (ii) potential, where in addition to the above, spherical perithecia-like structures were observed; (iii) positive, where perithecia containing asci and ascospores were observed. All strains were self-sterile and only one combination of strains produced fertile perithecia. From this fertile combination 168 individual ascospore cultures were isolated, including five from a single ascus. Forty-four monoascospore cultures were characterized with AFLP, confirming that these individuals were progeny from a sexual cross between the original two G. lindemuthiana isolates and that sexual reproduction in G. lindemuthiana is heterothallic in nature. Analysis of the parental strains with degenerate PCR primers indicated that sequences homologous to the HMG box of the MAT1-2 idiomorph are present in both parental isolates. This supports previous observations in other Glomerella species where the standard ascomycete configuration of distinct idiomorphs at the MAT locus does not hold true. The significance of these results is discussed.
Rodríguez-Guerra
Raúl
R
Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias. (INIFAP), Campo Experimental del Bajío, Celaya, Guanajuato, Mexico.
Ramírez-Rueda
María-Teresa
MT
Cabral-Enciso
Mariandrea
M
García-Serrano
Mónica
M
Lira-Maldonado
Zoraida
Z
Guevara-González
Ramón Gerardo
RG
González-Chavira
Mario
M
Simpson
June
J
D000595:Amino Acid Sequence; D001483:Base Sequence; D020231:Colletotrichum / Q000235:genetics / Q000502:physiology; D003433:Crosses, Genetic; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D049770:Genes, Mating Type, Fungal; D008800:Mexico; D008969:Molecular Sequence Data; D027805:Phaseolus / Q000382:microbiology*; D020081:Phyllachorales / Q000145:classification* / Q000235:genetics* / Q000472:pathogenicity / Q000502:physiology; D010935:Plant Diseases / Q000382:microbiology*; D012150:Polymorphism, Restriction Fragment Length; D017422:Sequence Analysis, DNA; D013172:Spores, Fungal
D005656:Fungal Proteins