Low biological efficiency is a defect in straw mushroom production. Mycelia of the straw mushroom were exposed to UV radiation to induce mutagenesis and improve the strains of straw mushroom for a high yield. A UV exposure time that yielded a survival rate of about 25% was applied for mutation induction. After UV treatment, 65 putative mutant strains were obtained and seven fast-growing strains were selected for further analysis. Mushroom cultivation experiments revealed that the biological efficiency of four of the new strains was approximately 30% higher than the parental strain. The radial mycelial colony growth rate was assessed on different media and under various temperature and pH conditions for physical characterization. The results indicated that the overall growth rates of the mutant strains were higher than the parental strain. Genetic characterization by random amplification of polymorphic DNA analysis revealed that the genome had been altered in the mutant strains.
