Morphological, ultrastructural and molecular variability studies of wild and mutant strains of edible Pleurotus species using growth yield, scanning electron microscopy and random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR)

There is a growing industry of edible mushroom production due to their nutritive value and the recognized fact that mushrooms are natural and healthy foods originating from an environmentally friendly organic farming system. The production of edible mushrooms is threatened by both abiotic and biotic factors, hence the need to improve breeding through genetic tools. In an attempt to determine the morphological and genetic diversity amongPleurotus species, fourteen different strains of Pleurotus ostreatus and Pleurotus floridawild type and their mutants were subjected to different morphological traits, ultrastuctural hyphae network studies and random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) marker. The mycelia growth yield on Petri-plates and in submerged fermentation indicated that the strains PO90 and PF30 were significantly different from the other Pleurotus strains used in this study at P < 0.05. Also, the microscopy result showed marked differences among the Pleurotus strains. The dendrogram based on RAPD analysis generated two different clusters. Out of 4 random primers, distinct polymorphism was observed by primers BG17, BG18, BG 23 and BG25. The percentage similarity among the Pleurotus strains varies between 40-100%.   Key words: Pleurotus species, submerged fermentation, scanning electron microscopy, biomass yield, random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR).