Development of improved strain of Pleurotus species by interspecific hybridization

Oyster mushroom (Pleurotus spp.) commonly called as Dhingri in India, is one among the commercially cultivated mushrooms throughout the world and stands second in world production. However, cultivated mushrooms face problems like loss of genetic diversity and strain degeneration. Hence, there is an increased demand for the development of new and improved strains with high production and better growth attributes. The present study was conducted to improve the strain of Pleurotus species by interspecific hybridization through crossing single spore cultures. Pleurotus djamor is an early yielding pink coloured oyster mushroom having leathery texture and low biological efficiency (BE). It was crossed with the high yielding, delicate Pleurotus florida and Pleurotus ostreatus, which required comparatively more days for primordial initiation. Two hybrids with blended characters of both the parents were developed by hybridization. The BE of the hybrids viz., P. djamor x P. florida and P. djamor x P. ostreatus, was improved by 34.38 and 48.48 per cent respectively over the parent, P. djamor. The days needed for primordial initiation were significantly reduced in P. djamor x P. florida and P. djamor x P. ostreatus by two days and three days respectively compared to the early yielding parent, P. djamor. Analysis of proximate content revealed that hybrids were superior in protein and fibre content. The genetic relatedness between parents and hybrids was evaluated using Random amplified polymorphic DNA (RAPD) and the hybrids exhibited more similarity to P. djamor.