Functional Study On Mitochondrial Protein SsMIT1 From Sclerotinia Sclerotiorum

Sclerotinia sclerotiorum(Lib.)de Bary is an common deadly vegetative plant pathogen with a wide range of hosts.Can infect more than 400 plants including a variety of important crops,eausing crop selerotia,and eausing serious loss of production and quality.Sclerotium caused by Sclerotinia in rapeseed which causes great damage to rapeseed production and often leads to great ecsonomic losses.The sclerotia of S.sclerotiorum can resist adverse living conditions,It plays an important role in the disease cycle of Sclerotinia.Screening for differential expression of genes during the formation of S.sclerotiorum,and studying its function in the process of sclerotia formation,it is helpful to explore the control measures of S.sclerotiorum,and has a great significance for controling sclerotinia in production practice.In this study,the mitochondrial carrier protein-encoding gene sequence SsMitl was cloned.According to the principle of homology recombination,And using the segmentation marker method to perform gene knockout on the target gene,SsMitl knockout mutant strains were obtained using PEG-mediated protoplast transformation techniques.Pure knockout mutants were purified by continuous picking of the hyphal tip.The role of SsMitl in the growth,development and treatment of S.sclerotiorum was studied.The main results are as follows:(1)Compared with the wild type,there are differences in the growth rate of SsMitl deletion mutant hyphae.The mycelial tip has many branches and the length is shortened.There is no significant change in acid production capacity.There are differences in sclerotia development.Mutants can still form sclerotia but the formation time is delayed,There were no signifieant differences in the dry weight of selerotia and the number of sclerotia.(2)Compared to wild strains,the lesions are significantly smaller in diameter.Which the gene deletion mutants were inoculated on leaves of rapeseed and soybean.It is speculated that SsMit1 is associated with the pathogenicity of S.sclerotiorum.(3)Under the action of stress factors such as Congo Red,SDS,sorbitol,NaCl,and KCl,compared to wild-type strains,the growth of the mutant on the medium containing Congo Red,SDS,sorbitol,NaCl,KCl was significantly inhibited.Under these five stresses,the mutant could not complete the development of sclerotia.In summary)SsMitl is involved in the sclerotia development and pathogenic process of S.sclerotiorum.This result provides a theoretical basis for the control of S.sclerotiorum,and its specific molecular mechanism needs further study.