Entomopathogenic nematodes as potential biocontrol of the orchard pest, flatheaded appltree borer (Chrysobothris femorata)

Chrysobothris femorata (Flatheaded Appletree Borer) is a pest of orchard and ornamental trees. The larvae cause damage that can severely impact the productivity or marketability of young trees, and can exacerbate other causes of poor tree health. C. femorata like other wood boring pests can be difficult to manage due to their cryptic life style of living as larvae under the bark of trees. Many traditional chemical insecticides cannot reach insects under the bark of a tree. Some forms of biocontrol can target insects in these cryptic habitats due to their ability to move through the environment after application.
Entomopathogenic nematodes (EPNs) are one such organism used in biocontrol. In laboratory assays using five strains of EPN we have shown that C. femorata larvae are susceptible. One strain of EPN caused 100% mortality in the insects within 3 days after inoculation in the laboratory with 500 infective juvenile EPNs applied. Additional first year field trials using the two most promising EPN strains will elucidate if the nematodes can navigate to the insect under natural conditions and achieve meaningful biocontrol efficacy.