Prodigiosin Produced by Serratia marcescens Enhances the Insecticidal Activity of Bacillus thuringiensis delta-Endotoxin (Cry1C) against Common Cutworm, Spodoptera litura

Abstract

Synergistic effects of chitinases A, B and C1, chitin binding protein and prodigiosin from Serratia marcescens on the insecticidal activity of delta-endotoxin, Cry1C, of Bacillus thuringiensis against the common cutworm, Spodoptera litura, were investigated. Only prodigiosin showed a potent synergistic activity with Cry1C on both the lethal and growth inhibitory activity. In the previous paper (Asano et al., 1999) a synergistic effect in the supernatants of S. marcescens culture on the Insecticidal activity of Cry1C was described. The supernatants from S. marcescens and partially purified prodigiosin showed a similar synergistic activity on the Insecticidal activity of Cry1C. The content of prodigiosin in the supernatants was estimated as 10% according to the absorbance at 467nm where prodigiosin showed a peak and the content seemed to be enough to explain the synergistic activity of the supernatants on the activity of Cry1C.