Effect of isolated bacteria and their supernatant from American cockroach’s ootheca on its hatching as a safety method for control in Jeddah governorate

Periplaneta americana is one of the hygienic pests and is considered a vector of several human diseases. They transfer pathogens biologically by vertical transmission from the mother to embryos through egg cases (ootheca). Forty types of bacteria were isolated from different parts of P. americana ootheca to study their effects on ootheca hatching. The objective of this study was to investigate the pathogenicity of isolated Bacillus subtills and their free cells to demonstrate their mechanism of action. Positive effects of bacterial cells and their free-cells on ootheca hatching were observed. Bacterial cells and their free cells were given to the ootheca by sparing method for 1, 2, 3 and 4 times in a month with different concentrations. The results showed that treatments of high concentrations of bacterial cells and their free cells had a significant effect on the mortality of all treated ootheca for four times as compared to the control. Also, high concentrations of each treatment were exhibit high shrinkage, dehydrated and rigid.  The present study reveals that the toxicity of bacterial cell of B. subtilis has great potential more than free-cells for biological control against P. americana ootheca.