MrXrn1 Involved in the Regulation of Conidiation and Pathogenicity in Metarhizium robertsii

doi:10.16409/j.cnki.2095-039x.2020.06.008

Abstract

Abstract: In the present study, functional analysis for the gene of MrXrn1 (5'-3' exoribonuclease, MAA_09154) was performed by using gene deletion (based on homologous recombination) and phenotypic analysis in Metarhizium robertsii. Our results showed that the conidial yields of ΔMrXrn1 were significantly decreased by 75.75%, compared to the wild-type (WT). More importantly, the results of bioassay showed reduced virulence for the ΔMrXrn1 mutants against Galleria mellonella through cuticle infection, the LT₅₀ of ΔMrXrn1 against G. mellonella was markedly longer than that of the WT. However, different fungal strains exhibited similar virulence in the direction injection bioassays. Furthermore, the results of appressorium formation assays showed that the induced appressorium formation rates were markedly decreased by 43.58% for the deletion mutants, compared with the WT. These results indicated that MrXrn1 is involved in the regulation of sporulation and virulence in M. robertsii. Our research provided a basis for improving the biocontrol effect of fungal insecticides.

Key words: Metarhizium, Xrn1, gene knockout, gene function

CLC Number:

S476.1

WANG Zhangxun, XU Xiuzhen, FENG Jianyu, ZHOU Quan, HUANG Bo. MrXrn1 Involved in the Regulation of Conidiation and Pathogenicity in Metarhizium robertsii[J]. Chinese Journal Of Biological Control, 2020, 36(5): 721-728.

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