Analysis On Environment Factor Of The Brown Blotch Disease To Pleurotus Spp. And Screening For Resistant Materials

The oyster mushroom is widely cultivated in China whose production is at the first place.Brown blotch disease, also known as bacterial spot or rust disease, is the most important factors which led to the decline of oyster mushroom’s quality. Brown blotch disease is difficult to eradicate when it break out. Pseudomonas tolaasii is the pathogen of brown blotch disease, and the main pathogenic factor is the tolaasin.The fruiting bodies of the tested strains were artificial inoculated with Pseudomonas tolaasii suspension, and then cultured in different environmental to observe the severity of brown blotch disease. The results suggested that the disease index of the tested strains, which were inoculated with pathogens and then cultured at20℃, RH80%, is the highest. In contrast, the disease index of the tested strains at25℃or30℃, RH95%is lower. Based on different substrate, the severity of brown blotch disease for the tested strains are also different. Statistical analysis showed that with the increase of corn flour in cottonseed hull based materials, the disease index decreased. Additionally, the disease index of the second flush was higher than the first one.In order to screen the resistant strains, the tested strains were made a comprehensive analysis of laboratory and field resistance.Taking mushroom mycelium confrontation with pathogens indoor, the degree of antagonism is used for t evaluation of resistance;The fruiting bodies of the tested strains were artificial inoculated with Pseudomonas tolaasii suspension outdoor,and the statistical disease index was defined as for the evaluation of resistance.20strains’resistance levels,to brown blotch disease caused by Pseudomonas tolaasii,were significantly different. CCMSSC00397、CCMSSC00358、CCMSSC00499、 CCMSSC00599、CCMSSC03764have higher resistance to brown blotch disease,and CCMSSC00328、CCMSSC00374、CCMSSC00419、CCMSSC00578、CCMSSC00616、 CCMSSC03841seemed more sensitive to P.tolaasii. Good linear correlation between the level of indoor mycelium resistance and outdoor disease resistance predict that evaluating the level of the mycelium resistance can be determined as a rapid method to screen brown blotch disease resistant strains.