A novel method for evaluating the particle distributional behavior of a spray-dried technical concentrate and a water-dispersible granule formulation of Bacillus thuringiensis subsp. Israelensis in an aqueous column.

A novel method for evaluating the particle behavior of a spray-dried technical concentrate and a water-dispersible granule (WDG) formulation of B. thuringiensis subsp. israelensis in an aqueous column was established. The objective was to determine the distributional behavior (minus any extraneous environmental factors) of B. thuringiensis subsp. israelensis within a water column over time. Studies showed a fairly even distribution of particles over a 16-h period for the technical concentrate and WDG formulation. The particle behavior of the WDG formulation also showed homogeneous distribution of particles at 64 and 128 h. The results demonstrated that Brownian motion plays a significant role in the particle distributional behavior of this entomopathogen.