Monospore Cross Breeding And Screening Of New Strains Resistant To Disease Of Oyster Mushroom

In this experiment, eight parent strains of oyster mushroom including Pleurotus ostreatus, P. pulmonarius, P. citrinopileatus and P. diamor were used for collecting basidiospores,through the monospore cross breeding, the hybrid progeny strains were obtained, and they were examined the competitive ability against Trichoderma spp. and Pseudomonas tolaasii using a dual culture system and bag growing system. The purpose of this study is for breeding and screening new strains resistance to disease of oyster mushroom. The results are as follows:1.309monocaryotic strains of oyster mushroom were obtained, most of them were selected for cross breeding, and864cross combinations were produced. Then77new crossing progenies strains were obtained by bearing experiments. Through second screening,27strains were obtained with higher growth rate, vigorously mycelium growth, perfect shape of fruit bady and different with parents.2. Through RAPD analysis between hybrid strains and parents,25hybrid strains, which are the new strains have significant genetic differences with parents,2hybrid strains genetic variation of sterile lines was close to parents.3. By comparing the mycelium growth with different temperature, four strains as P2, P3, P6and P8are growing faster at25℃. The strains as P6, P19, P20are growing faster at30℃, and the strain as P19is growing fastest in all strains, the growth rate of mycelia was faster than their parents as4.8mm/d,8.9mm/d. Six strains as P2, P20, P23, P24, P25had the ability of high temperature tolerance.4. Compared experiments among materials, fruit body yields of ten strains were higher than their parental strains, five strains were higher than one of their parental strains. The highest yield as P23and P30. 5. Though examined the competive ability of hybrid strains against Trichoderma harzianum T12and Trichoderma pleurotum T33, The antagonistic experiment showed that three strains as P4, P7, P14had stronger resistant to the T12, five strains as P10, P14, P16, P20, P21had stronger resistant to T33. In fruiting experiment, the fruiting, among1parent were100%, the7strains were lower.6. Through the flat antagonism, the27hybrid strains and parental strains in accordance with the level of resistance were divided into highly resistant, middle resistant, low resistant and the nonreactive varieties. There were five highly resistant as P30, P4, P8, P32, P40, the resistance level are70.07%,69.56%,67.82%,63.5%,161.57%; the middle resistant has15, Including13hybrid strains and2parental strains; row resistant has14, among which9hybrid strains and5parental strains were included;1hybrid strains was nonreactive varieties. The fruiting bodies of the tested strains were artificial inoculated with Pseudomonas tolaasii suspension, and the statistical disease index was defined as for the evaluation of resistance. Good linear correlation between the level of indoor mycelium resistance and outdoor disease resistance predicted that evaluating the level of the mycelium resistance can be determined as a rapid method to screen brown blotch disease resistant strains.