Generation and Evaluation of Hybrids of Pleurotus giganteus (Berk.) Karunarathna & K.D. Hyde and Identification of the Hybrids using ISSR Markers

A commercial strain of Pleurotus giganteus from China which was recently domesticated in Malaysia was reported to have retarded pinhead formation resulting in heavy losses for farmers. The aim of this study was to generate new hybrids of P. giganteus with higher yield for commercialisation Malaysia. The commercial strain of P. giganteus (China) and a wild strain from Malaysia were subjected to intraspecific breeding. Of the 56 combinations, 16 hybrids were obtained. All the parents and hybrids were subjected to linear growth assessment. The hybrids were grouped into slow-growing (growth rate < 0.29 cm/day) and fast-growing (growth rate ≥ 0.30 cm/day). The fast-growing hybrids were tested for susceptibility to Trichoderma sp. The parents and three hybrids that were least susceptible to Trichoderma sp. were then cultivated. Soil-casing method was able to solve long, coiling stipe formation of P. giganteus. The parents and hybrids showed variation in the number of days for pinhead formation and number of fruit bodies formed. The hybrid with the highest yield (IH 32) had a 32% higher biological efficiency than the parents. Inter simple sequence repeats (ISSR) amplifications were carried out to confirm the generation of the hybrids. Two out of three selected hybrids were confirmed to be true hybrids.