Tests were conducted to determine the effect of the fungus Beauveria bassiana (B.b.) on underground of the Colorado potato beetle (CPB), Leptinotarsa decemlineata. Two levels of B.h., g/m2 and 75 g/m2 , were suspended in water and sprinkled over the surface of the ground in cages to which CPB were added, either as overwintering adults or as 4th instar larvae of the 15t generation. Efficacy of treatments was determined by counting emerged adults. Neither level of B .b. increased mortality in overwintering adults. The highest level of B.h. caused a significant decline in emergence of adults from the 1st generation 4th instars. The 7.5 g/m2 treatment level did not significantly differ from control treatments.
Cantwell, George E.; Cantelo, William W.; and Schroder, Robert F. W.
"Effect of Beauveria Bassiana on Underground Stages Of the Colorado Potato Beetle, Leptinotarsa Decemlineata (Coleoptera: Chrysomelidae),"
The Great Lakes Entomologist, vol 19
Available at: https://scholar.valpo.edu/tgle/vol19/iss2/6