Studies On Cell Engineering Breeding And Cultivate Of Pleurotus Eryngii

Edible fungi, which belongs to natural, nutritional and multifunctional food, has the characteristics of high-protein and low-fat, and thus accord with the new international requirements about food of low-salt, low-sugar and high-protein. As the understanding of nutritive value and medicinal value of edible fungi is deeper, strain breeding of edible fungi has become the focus of the scientific researcher.The breeding technique of protoplast is an essential method of edible fungi breeding, for its simple operation, easy acquisition, very sensitivity to mutagenic factor. It has been applied to breed various kinds of edible fungis.Strain breeding of Pleurotus eryngi was studied by using protoplast regeneration and UV mutagenesis techniques.269 regenerative strains had been obtained. The optimum conditions of protoplast preparation and regeneration of Pleurotus eryngi were studied in the thesis. The results showed the higher protoplast yield of Pleurotus eryngii about 1.75×107 units/mL was obtained when 96-hour mycelial was treated with mixed enzyme solutions consisting of 1% Snailase and 1% Cellulase at 30℃for 2 hours. The regenerating ratio could reach 4.8% with mannitol as the osmotic stabilizer. Pleurotus eryngi protoplast is sensitive to the ultraviolet radiation, so low dose can reach high lethality rate. But the positive variation rate is relatively higher when the lethality rate is in the range of 70%-80%. Therefore,15s was chosen when the lethality rate was 80%.New strains are selected by antagonism tests, which possess quick growth rate, high yield and great agronomic traits.A new strain 08X-013 is selected, which also possess quick growth rate, high biomass, good consumption ratio of reducing sugar and high extracellular enzyme activity. Study on esterase isoenzyme showed that 08X-013 was an excellent strain for fermentation which was different from the original strain.The fruiting experiment test showed that 08X-013 had shorter bagful, flower bud sprouting, and producing mushroom time than the original strain, and its biological efficiency was 65.2%, which was increased by 11.8% at significant difference level comparing with the original strain. All the results above showed that 08X-013 was an excellent strain for cultivation.