GENETIC RELATIONSHIPS BETWEEN MEXICAN SPECIES OF PLEUROTUS ANALYZING THE ITS-REGION FROM RDNA.

Mexico is considered a country having great biodiversity, but genetic resources of edible mushrooms are as yet poorly studied. Twenty five strains of oyster mushrooms (Pleurotus) isolated from tropical, subtropical and temperate regions were studied. Strains were identified sequencing the ITS1-5.8S-ITS2 region from the rDNA. Six species were determined using neighbor-joining and maximum parsimony analyses with high levels of support: P. "agaves", P. djamor, P. levis, P. ostreatus, P. pulmonarius, and P. smithii. Further collections and genetic analysis are needed for P. "agaves" and P. smithii. Most sequences from Mexican strains were clearly separated in the consensus trees from reference strains of European and North American origin. The exception was the sequence ECS-0156 of P. pulmonarius, which was grouped with those of reference strains from North American and European origin, opening the possibility that strains cultivated commercially may have escaped from cultivation. Species identified represent a broad genetic base for breeding programs, and good potential for commercial cultivation. [ABSTRACT FROM AUTHOR]