Fig. 4
Protection of silkworm larvae by Ma. sciuri against fungal infections. a, b Protection of the conventionally reared (CR) silkworm larvae against M. robertsii (Mr, a) and B. bassiana (Bb, b) infection by Ma. sciuri. c, d Protection of the axenic silkworm larvae against M. robertsii (c) and B. bassiana (d) infection by Ma. sciuri. e, f Deletion of Msp1 in Ma. sciuri impaired the bacterial protection of CR (e) and axenic (f) silkworm larvae against M. robertsii infection. The newly molted 5th instar larvae were immersed in Ma. sciuri (Ms) cells (OD600 = 5) for 5 s, and after 24 h the insects were topically treated with fungal spore suspensions (5 × 107 conidia/ml in 0.05% Tween 20). Log-rank tests were conducted between the survival curves: *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001. Mock control insects were treated with 0.05% Tween 20. The insects only treated with Ma. sciuri (Ms) were also included as controls. The number of insects finally included in analysis is shown in parentheses