- Dimond, John B.
University of Maine
Bacillus thuringiensis applied to plots in Maine in 1973 did not provide tree protection or detectable reductions in spruce budworm numbers. This contrasts strongly with the successful performance of B.t., plus the enzyme chitinase, in 1972. The results of these tests in Maine and tests in several areas of Canada suggest that B.t. alone will work reliably only against budworm populations stressed by cold, starvation, or other diseases. Chitinase appears to duplicate the effects of such stress. Research is needed to discover alternate materials to provide stress in budworm populations, enhancing the activity of B.t.