CAT and infection: On this basis, a further exploration of the impact of each strain on the main redox system of the larvae revealed that in the larvae of the Bb01 treatment group, SOD, CAT, and POD were involved in the redox reaction, and the content of H2O2 was not affected by GSH but by the activity of POD, resulting in the accumulation of H2O2 in the larvae at 6 and 24 h post-infection.