MICROBIAL INSECTICIDE PREPARATION, METHOD FOR PREPARING IT AND PROCEDURE FOR CONTROLLING INSECT PESTS WITH SUCH PREPARATION.

摘要

An improved insecticidal composition is disclosed comprising a microbial agent of viral or bacterial origin embedded in a microbead, wherein the microbead contains sufficient radiation-absorbing material to effectively shield the agent from sunlight-induced inactivation. Typically the microbead is comprised of a nucleic acid and a protein-containing material, and is stabilized by chemical crosslinking. A method for preparing a microbial insecticide composition is also disclosed comprising: mixing a buffered aqueous solution containing a microbial insect pathogen with an aqueous solution containing a nucleic acid, and mixing the said mixture with an aqueous solution containing a proteinaceous material, thereby spontaneously forming microbeads having the pathogen embedded therein. Typically the microbeads are subsequently stabilized by treatment with chemical crosslinking agents, and typically, prior to the two mixing steps, the microbial insect pathogen is cleaned by washing and its surface charge is modified by the addition of a protein-modifying agent adapted to provide a more uniform surface charge.