Figure 1.

Hydrogen cyanide-deficient mutants exhibit reduced injectable insecticidal activity. (A,B) Injectable activity against Galleria mellonella. Thirty larvae per treatment were injected with 2 × 10³ bacterial cells and survival was recorded hourly. (C,D) Oral activity against Plutella xylostella. For Pseudomonas protegens CHA0 (C) 64 larvae were exposed to artificial diet inoculated with 4 × 10⁶ bacterial cells and for Pseudomonas chlororaphis PCL1391 (D) 32 larvae were exposed to 2 × 10⁷ bacterial cells. Sterile 0.9% NaCl solution served as control. Treatments that differed significantly from their respective wild-type strain (Log-Rank test p ≤ 0.05, Survival Package in R) are marked with an asterisk. This figure shows the survival curves of one representative experiment per strain and insect system. The LT₅₀ values corresponding to these experiments and to a repetition of them are depicted in Tables 2, 3. Solid black line, wild-type strain; dotted blue line, mutants deficient for hydrogen cyanide production (Hcn⁻, CHA5103, PCL5103); dash-dot green line, 0.9% NaCl solution control.