Tunisian Journal of Plant Protection (Mar 2018)
Beyond Bt: New Bacterial Resources for Insect Biocontrol
Abstract
The Gram-positive bacterium Bacillus thuringiensis (Bt) is the economically most important entomopathogen for insect biocontrol, and for excellent reason a large part of the effort invested in the development of microbial insecticides has concentrated on Bt strains and their cry genes. Hundreds of cry gene sequences have been determined from nature, and molecular modeling has been used to create artificial recombinant Cry proteins with potentially new properties. However, alternative insect biocontrol agents are increasingly solicited. More recently, research efforts have concentrated upon bacterial insect-pathogens as potential biocontrol resources as, e.g., non-cry toxins of Bt and other bacteria of the family Bacillaceae as well as the bacterium Saccharopolyspora spinosa (Actinobacteria). Moreover, several different γ-proteobacterial entomopathogens belonging to the species Serratia entomophila, Yersinia entomophaga or Pseudomonas entomophila as well as to the genera Providencia or Rickettsiella are currently being evaluated for their biocontrol potential. The present literature review gives a brief update on these entomopathogens and toxins.
