We further concluded that trypsin (Pr2) and metalloproteases (Pr3) do not contribute to the fungal infection process, while the subtilisin (Pr1) inhibitor TPCK and cysteine protease (Pr4) inhibitor CI1 play critical roles in the pathogenicity of Metarhizium anisopliae strain IPPM202, thus providing a foundation for targeted biocontrol strategies. The gene discussed is PRTN3; the disease is fungal infectious disease.