Figure 5. The resistant subpopulation is the major population present during septicemia in insects.

(A) Representative diagram of the experimental procedure. (B) Bacterial growth and insect larval mortality following the injection of P. luminescens TT01 into Spodoptera littoralis. We injected 3 × 10⁴ bacteria into each larva at time zero. The histogram shows the mean numbers of CFU recovered from four larvae per time point, after plating on nutrient agar (black bars) or nutrient agar supplemented with polymyxin B (gray bars). The error bars indicate the standard error of the mean. The lines indicate larval mortality rates (for 20 larvae per treatment). One representative experiment from more than three independent experiments carried out is shown. (C) The procedure and representation are as in panel B, except that the insect cadaver extracts were plated on agar seven days after injection.