Temperature effects on Bacillus thuringiensis controlling Leptinotarsa decemlineata
In the USA, experiments were carried out to determine the influence of temperature on the capability of Bacillus thuringiensis subsp. san diego to control colorado beetle, Leptinotarsa decemlineata (EPPO A2 list).
At temperatures between 28° and 33° C Bacillus thuringiensis subsp. san diego induced a 100% mortality on first instars of the beetle while at 18° C mortality was only 45%.
The authors suggest that the application of Bacillus thuringiensis subsp. san diego should take place in midmorning to secure a long time period over 24° C for the control of early instars of this pest.
Ferro, D.N.; Lyon, S.M. (1991) Colorado potato beetle (Coleoptera: Chrysomelidae larval mortality: Operative effects of Bacillus thuringiensis subsp. san diego.
Journal of Economic Entomology 84, 806-809.