NOTES ON THE PATHOGENICITY OF SERRATIA MARCESCENS BIZIO FOR THE COCKROACH BLATTELLA GERMANICA L.

Abstract

Serratia marcescens Bizio sporadically caused mortality in cultures of the German cockroach, Blattella germanica L. Extensive feeding tests showed this bacterium is not normally pathogenic, per os, for the insect. The LD₅₀, by injection, for the cockroach is approximately 38,000 bacteria per insect. The possible modes of invasion of the insect gut are discussed briefly.