Biological Characteristics Of The Pathogen Of White Fungus White Fungus And Soil Microbial Diversity In The Diseased Area

Morel is a generic name for the species of Morchella.It is one of the five rare edible fungi in the world and has important economic value.In recent years,the artific ial cultivation of morel has made remarkable progress,and it has been widely used in more than 20 provinces and cities in China such as Sichuan,Yunan and so on.The artificial cultivation of morel has become an emerging edible fungus industry.White mold is one of the major diseases in the cultivation and production process of morel.White mold mainly infects the primordial and fruiting bodies of morel,which seriously affects the production and quality of morel.In this study,the species of pathogenic bacteria were determined by molecular identification and morphological observation,and the microbial diversity of Morchella soil was analyzed by high-throughput sequencing.The research results are as follows:The soil microbial diversity of the white mold of Morchella showed that the bacteria community structures varied from diseased soils and non-diseased soils.And.The occurrence of the community structure of bacteria and fungi in the soil was reorganized to some extent.Three susceptible strains(P-B,P-G,P-N)were isolated from different pathogenic areas,and identified as Paecilomyces penicillatus by morphological characteristics and ITS4,5 sequence analysis.The strains P-B,P-G,P-N,pathogenic bacteria which are white mold of Morchella were verified.Further studies showed that the optimum carbon sources for the three strains were maltose and sucrose,and the optimum nitrogen source was yeast extract or yeast paste.The mycelium of the three strains can live at 5°C-30°C,but the optimum growth temperature is 15°C-20°C,and the lethal temperature is 42°C-45°C.It can live at pH 4.0-10.0 and pH 7.0 is optimal.Under the certain light intensity,the mycelial growth of pathogenic bacteria can be prom.The results of drug susceptibility test showed that the inhibition rate of Bacillus subtilis preparation and carbendazim on the mycelial growth of three pathogenic bacteria was 100%,and Bacillus subtilis preparation could be used as a safe and effective biocontrol agent for white mold of Morchella.The microbial diversity of Morchella leucomycosis soil showed that there were significant differences between Morchella and non-morbidity soil samples in the abundance of some genera of bacteria.For example,the abundance of SphinGomonas and CellviBrio in Morchella of soil samples was lower,while the genus FlavoBacterium and PedoBacter were more abundant,and Morchella was more abundant in the overall bacterial diversity,and the genus of Flavobacterium and PedoBacter were abundant.The soil of the Morchella was more abundant than the unaffected soil in the overall bacterial diversity.In terms of fungi: the abundance of some genus in the fungal genus was significantly different between the infected and the unaffected soil.The abundance of Coprinellus and Discosia was significantly different,but the abundance of Penicillium was very close.The number of fungal species in the soil samples of Morchella is small and the diversity is small.Therefore,this study found that the bacterial and fungal diversity of the diseased soil and the unaffected soil and the dominant genus were different.The occurrence of the white mold of the morel was reconstituted to some extent the community structure of bacteria and fungi in the soil.