Spawn viability in edible mushrooms after freezing in liquid nitrogen without a cryoprotectant
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- 作者：Mata ; Gerardo ; Pé ; rez-Merlo ; Rosalí ; a
- 关键词：Edible mushroom cultivation ; Lentinula ; Pleurotus ; Volvariella ; Germplasm conservation ; Liquid nitrogen
- 刊名：Cryobiology
- 出版年：2003
- 出版时间：August, 2003
- 年：2003
- 卷：47
- 期：1
- 页码：14-20
- 全文大小：123 K
文摘
Five strains of edible mushrooms (Lentinula boryana, Lentinula edodes, Pleurotus djamor, Pleurotus pulmonarius, and Volvariella volvacea) were studied. Spawn were prepared from sorghum seeds and then incubated for 14 days under optimum conditions for each species. Once covered by mycelia, the sorghum seeds were placed in polycarbonate vials for freezing in liquid nitrogen. The effect of adding a cryoprotective solution before freezing (either 10 % glycerol v/v or 5 % dimethylsulfoxide v/v) was evaluated as a function of mycelial growth and percent viability. Three main treatments were undertaken: (1) freezing with a glycerol or dimethylsulfoxide cryoprotectant, (2) freezing with water and (3) freezing without cryoprotectant or water. Samples were maintained frozen for a week, after which time they were thawed (10min at 30°C) and the seeds placed in Petri dishes with a culture medium. A recovery rate of 96.8 % was obtained for the total number of samples summed over all strains and treatments. In contrast, 99.2 % of the samples frozen without cryoprotectant were recovered. The recovery of frozen mycelia was delayed with respect to a control group, which was not frozen. However, no difference was observed in percent recovery and mycelial diameter when a new series of spawn was prepared from mycelia that had been previously frozen. Results obtained from this experiment demonstrate that an adequate recovery of mycelia can be obtained without using a cryoprotectant. This capacity might enable large quantities of commercial mushroom strains to be handled at reduced production costs. It is suggested that the mycelia survived freezing without cryoprotectants because they were embedded and protected within the sorghum seeds used to elaborate the spawn.