A low-cost, granular matrix formulation of Bacillus thuringiensis Berliner var. kurstaki, composed primarily of corn flour and containing a feeding stimulant composed of cottonseed flour and sugars, was developed for use against the European corn borer, Ostrinia nubilalis (Hubner), on whorl-stage corn. Laboratory experiments indicated that a corn flour agricultural commodity product was a suitable carrier, that the feeding stimulant enhanced the activity of B. thuringiensis, and that the granular matrix protected B. thuringiensis from photodegradation. Results of a greenhouse test showed higher mortality of the European corn borer on corn plants treated with the granular matrix than on plants treated with a standard commercial granular formulation of B. thuringiensis. Mortality with either treatment was increased by application of simulated rainfall. In a field test, the granular matrix applied at a rate of 5.5 kg/ha gave control comparable with that achieved by the commercial standard applied at a rate of 11 kg/ha. Results indicated that increased efficacy or reduction in costs of management of the European corn borer with B. thuringiensis should be possible through the use of the granular matrix formulation.
All Science Journal Classification (ASJC) codes
- Insect Science