Volume 16 Part 1 Article 23
Title: Spawn Viability and Mushroom Production in Pleurotus Strains Frozen for Eight Years in Liquid Nitrogen
Authors: G. Mata, D. Salmones and R. Gaitán-Hernández
In order to determine if long-term cryogenic preservation effected spawn viability and mushroom productivity of Pleurotus spp., three strains of P. columbinus and one strain of P. pulmonarius were cropped following eight years of storage under liquid nitrogen. Spawn was prepared using sorghum seeds incubated for 14 days under optimum conditions. Once fully colonized by mycelium, the seeds were placed in polycarbonate vials containing 10% glycerol (20 seeds per vial; two vials per strain). The samples remained in contact with the cryoprotective solution for 1 h, and then were directly frozen in liquid nitrogen. Samples were maintained frozen for eight years, after which time they were thawed (10 min at 30°C) and the seeds placed in Petri dishes on a culture medium. Percent viability, mycelial growth rate and mushroom production on pasteurized oat straw were evaluated. A recovery rate of 100% was obtained for all strains, with mycelium regenerating from the sorghum seeds between one and five days after thawing. No significant differences were observed in mycelial growth rate between controls and frozen samples. Mushrooms were produced over three harvests during a maximum of 52 days. Only two strains showed slight differences in mushroom production between the control and frozen samples. No differences in mushroom morphology or size were observed.Please login to download the PDF for this proceeding.