Local production of primary powder of bacillus thuringiesis serotype H-14 in Iran and determination of its insecticidal properties against culex pipiens and anopheles stephensi

ABSTRACT

Three media formulated from molasses and cornsteep liquor and another media based on the basal medium formulation of IPS-82 were assessed for the growth and production of insecticidal properties of B. thuringiensis H-14 Bacterial powders prepared from the broth cultures were assayed against the larvae of Culex pipiens and Anopheles stephensi. A standard powder of IPS-82 was included in the assay for comparison. Good growth was obtained in all the media and all powders were effective against the two types of mosquito larvae. Media with the basal medium formulation of Institute Pasteur Paris were the most effective. Molasses III media was also very favorable. The concentrations required to kill 50% of the larvae of Culex pipiens and Anopheles stephensi for these two were as follows - Media with the basal medium formulation of Institute Pasteur Paris 24hr. Lc50 and it's 95% confidence limits of Culex pipiens and Anopheles stephensi = 0.0025,0.0031,0.0018 mg/lit 0.1792,0.2603,0.1508 mg/lit - Molasses III Media 24hr. Lc50 and it's 95% confidence limits of Culex pipiens and Anopheles stephensi = 0.0103,0.0115,0.0092 mg/lit 0.1994,0.2223,0.1769 mg/lit. The investigation shows that these media can be used for the production of B.thuringiensis H-14 primary powder