Four-year-old wild-type cottonwood (P. trichocarpa) suffered significant defoliation at normal infestation levels of the leaf beetle (Chrysomela scripta). The wild-type trees had a net growth that was 13% less than those over-expressing the cry toxins from Bt. The trees producing the Cry3A toxin had very low feeding damage [165]. Eucalypts over-expressing a sequence-enhanced version of cry3Aa produced leaves that were toxic to three beetle species [166].
wild-type cottonwood
Four-year-old
year-old
wild-type trees
net growth
13%
%
beetle species
three