Genetic diversity in nineteen strains of Pleurotus was studied using morphometric traits and growth factors. Ability of the isolates of these strains to tolerate different ranges of temperature and pH were evaluated. Highest mycelial growth rates were obtained at 25 °C (mutants and hybrids) and 30 °C (wild type), while LAU 90 (mutant) performed satisfactorily at all evaluated temperature ranges (15-35 °C). Highest mycelial yields (dry weight) were produced by LAU 90 at different pH regimes (4.0 - 9.0), while hybrids LN 97 and LN 98 maximally produced mycelial yield at pH 5.0 and 7.0, respectively. Analysis od Principal component (PC) revealed that components of these strains accounted for 86.1% of total variations among the strains with first PC recording 44.6%. The dendrogram discriminated nineteen Pleurotus genotypes into two major genetic groups with mutants and hybrid strains in Cluster A, separated distinctly from wild parents in Cluster B, indicating genetic diversity. The expression of heterosis can be maximized by information obtained among the hybrid strains and mutant (LAU90) strain. The hybrid (LN98) strain with superior performance may be selected for adoption in commercial mushroom production.
