Function Research Of Conidiation Related Genes In Botrytis Cinerea

Botrytis cinerea is an airborne plant pathogen attacking over 200 kinds of plants,including tomato,strawberry,grape and many species of flower.The stress resistance of B.cinerea is extremely powerful.It can survive with sclerotia and conidia in hostile environment.Researching the mechanism of sclerotia and conidia development and pathogenicity will establish theoretical foundation for the effective control of the gray mold.According to the RNA-Seq results during mycelium growth and sclerotia formation,BC1G₀0689 and BC1G₀3293,which have a highly different expression level between two stages,were selected to study in B.cinerea,and the primary results are shown:1.RNA-Seq results showed that the transcript level of BC1G₀0689 during sclerotial formation stage was significantly lower than that during mycelium growth stage.BC1G₀0689 encode a protein with an acid sphingomyelinase domain.The gene knockout strains ?BC1G₀0689-19 and ?BC1G₀0689-21 were obtained by using the homologous recombination methods.The transcript level of BC1G₀3293 during sclerotial formation stage was obviously higher than that during mycelium growth stage.The structure of the protein encoded by the gene shows a high similarity with a maltose-binding periplasmic protein in Escherichia Coli.There is no research report on the function of the protein in fungus by now.We used the homologous recombination methods to get the knockout mutants ? BC1G₀3293-2 and ?BC1G₀3293-4,we also got the complemented transformants ?BC1G₀3293-2-C2 and ? BC1G₀3293-2-C3 by Agrobacterium tumefacims-mediated transformation technique.2.Compared with the wild type B05.10,the knockout mutants ?BC1G₀0689-19 and?BC1G₀0689-21 showed no significant differences on colony morphology,hyphal tip morphology,the rate of mycelium growth,virulence on tomato leaves and the dry weight of the sclerotia.But deletion of BC1G₀0689 induced obvious decrease of conidia production,the conidia production of the knockout mutants is approximately70% of the wild type strain B05.10.These results suggested that BC1G₀0689probably plays an important role in the conidiation of B.cinerea.3.The conidia production of the gene BC1G₀3293 knockout mutants had obviously decreased and was approximately 45% of the wild type strain.And the conidia production of the complemented transformants had recovered obviously.Compared with B05.10,the deletion of the gene did not influence the rate of mycelium growth,colony morphology and the dry weight of the sclerotia on minimal medium added with maltose or sucrose.Our research results revealed that BC1G₀3293 is involved with the regulation of the conidiation of B.cinerea.