Isolation of Bacillus thuringiensis strains from Saudi Arabia soil and study of their potential efficiency against the lepidopteran pest Ephestia kuehniella

Insect pests represent a major threat to food crops and human health, therefore have be combated in several ways, including chemical methods. However, researchers demonstrated that these molecules are dangerous for the farmers, consumers environment general. For this reason, scientists permanently searched friendly alternatives such as use of bacterium Bacillus thuringiensis classified one best insect pathogens. This microorganism is known by its ability produce two types insecticidal proteins, Vegetative proteins (Vip) delta-endotoxins produced during vegetative sporulation stages growth, respectively. In present study, 15 B. strains were isolated from soil collected different regions Saudi Arabia (Al Baha, Jeddah, Khulis Yanbu). isolates then according shape their parasporal crystals identified under microscope content crystals. Delta-endotoxins efficiency was investigated promising very active. After 5 days-treatment, 14 7 killed Ephestia kuehniella larvae with low LC50 about 59.18 65.67 mg/cm2, The results described study proved new could great interest control lepidopteran using bioinsecticide formulations.