Study On Genetic Differentiation Of Hybrids From Cultivated Strain And Wild Strain In Oyster Mushroom

Cultivated strain HP, G32-2 of Pleurotus ostreatus and wild strain ZJJ, WDS were used in this study.38 monokaryons from strain HP,46 monokaryons from strain G32-2,55 monokaryons from strain ZJJ and 40 monokaryons from strain were obtained respectively by single basidiospore isolation.10 monokaryons from each parental strain were randomly selected for hybridization. Using the clamp connection as a marker,14,13 and 38 hybrids were obtained from the combinations of HP×ZJJ,HPxWDS and G32-2xZJJ respectively.According to the different antagonist reaction between hybrids and parents, the 14 hybrids from hybrid combinations HP×ZJJ were divided into 4 types. The mycelia growth rate on different media showed dominant differentiation.The result of cultivation test showed that one hybrids could not fruit and yield of the others were lower than that of the cultivated strain HP, while the yields of 5 hybrids were higher than that of the wild strain ZJJ. Among the hybrids, most pilei showed similar color with that of parent HP (white),3 hybrids formed fruitbodies without pilei. The analysis of hybrids agronomic charateristics showed that the coefficient of variation (CV) of yield per bag was the largest (37.2%), the others in the order were primordial initiation days (25.4%), stipe length (21.8%), full colonization time (21.0%), average weight of single fruitbody (16.2%), Longitudinal diameter of stipe (14.7%), pileus thickness (14.5%), mycelium growth rate on spawn medium (14.0%), mycelium growth rate on PDA medium (13.2%), horizontal diameter of pileus (13.0%) and stipe diameter (9.4%).The mycelia growth rate of 13 dikaryons from hybrid combinations HP×WDS showed dominant differentiation on different media.The result of cultivation test showed that 3 hybrids could not fruit normally, one hybrid formed fruitbodies with bowling shape and several agronomic characters showed different genetic differentiation:the CV of yield per bag was the largest (32.4%), the others in the order were full colonization time (21.2%), average weight of single fruitbody (18.3%), Longitudinal diameter of stipe (18.2%). primordial initiation days (17.9%), mycelium growth rate on spawn medium (16.9%), pileus thickness (13.6%), stipe diameter (12.1%), horizontal diameter of pileus (12%), stipe length (11.7%), and mycelium growth rate on PDA medium (8.3%).The result of cultivation test of 38 dikaryons from hybrid combinations G32-2 X ZJJ. showed that 5 hybrids could not fruit and one hybrid formed deformity fruit body, the agronomic characters of hybrids showed different genetic differention, The mycelia growth rate on different media showed dominant differentiation. The CV of mycelium growth rate on spawn medium (22.5%) was the largest, the others in the order were average weight of single fruitbody (21.7%), full colonization time (17.5%), pileus thickness (15.8%), stip diameter (15.3%), stipe length (14.9%), longitudinal diameter of stipe (13.2%), horizontal diameter of pileus (13.0%), primordial initiation days (12.4%), yield per bag (10.2%), mycelium growth rate on PDA medium (9.8%) was the smallest (10.2%). Beacause the agronomic characters of hybrids differentiated significantly, we can according to the different targets of selection breeding to develop repeated screening test.