Exploring the host range of Metarhizium novozealandicum (C14) against some common insect pests in New Zealand

Metarhizium novozealandicum (C14), isolated from a kiwifruit nursery soil in Nelson, is a potential biocontrol agent for grass grub as has shown high pathogenicity towards the larvae. If isolate C14 is to be used as a grass grub biocontrol agent, it is likely to remain in grass grub populations longer if alternate hosts are also present. In addition, commercial development of biopesticides can be more successful if the active agent is able to infect more than a single pest species. The virulence of C14 against five other New Zealand insect pests (Lepidoptera Plutella xylostella, Helicoverpa armigera and Wiseana sp., Hemiptera Myzus persicae, and Coleoptera Tenebrio molitor) was investigated using bioassays. These pests belong to three orders and have a range of differing life histories and ecological traits. M. novozealandicum (C14) had high pathogenicity against two of these insect pests, H. armigera and T. molitor, but was less effective against P. xylostella, Wiseana sp. and M. persicae