Bacillus associated with Colorado Potato Beetle – Leptinotarsa decemlineata Say – and the Mottled Umber – Erannis defoliaria Clerck – in Georgia

Abstract: For the identification of endemic species of Bacillus in agricultural and forest ecosystems of Georgia, infected and healthy individuals of Colorado Potato Beetle – Leptinotarsa decemlineata Say – and caterpillars of the Mottled Umber – Erannis defoliaria Clerck – were collected at different larval stages. Ten of the 20 isolates [BZ1, BZ2, BZ3, KM1, KM2, KM3, KM4, KM5, KM5 (1), M5 (2)] were gram-positive. For the evaluation of spore formation isolates were cultivated in nutrient broth and on Selective media and were analyzed under the microscope. For the purpose of establishing the formation of crystal proteins the proteinaceous range of gram-positive isolates was studied by SDS-PAGE. Isolates BZ1, BZ2, KM1, KM2, KM3, KM4, KM5 were found to have a high protein content which ranged in size between 130 kDa and 66 kDa. Microscopic analysis revealed the existence of spores in KM2, KM3 and KM5 isolates. For the purpose of identifying crystal inclusions these isolates were transferred onto selective media. A 24-hour microscopic analysis of culture didn’t show the existence of any crystal inclusions.