Parasitism of gum leaf skeletoniser (<i>Uraba lugens</i>) in New Zealand

Abstract

The gum leaf skeletoniser (Uraba lugens) a significant pest in Australia is now well established on Eucalyptus spp in the Auckland region One larval parasitoid (Meteorus pulchricornis) and two pupal parasitoids (Xanthopimpla rhopaloceros and Anacis sp) were recorded from U lugens collected in southwest Auckland Parasitism of M pulchricornis and X rhopaloceros against U lugens and other hosts in New Zealand (Helicoverpa armigera and Epiphyas postvittana respectively) was compared using nochoice and choice tests under controlled conditions Uraba lugens is a suitable host for development of both M pulchricornis and X rhopaloceros Choice tests revealed that M pulchricornis prefers H armigera larvae to U lugens Attack by X rhopaloceros occurred only when host pupae were presented within their cocoons Meteorus pulchricornis may compete with proposed classical biological control agents introduced against U lugens while X rhopaloceros is more likely to complement them

Will competition from Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae) limit the success of the potential biocontrol agent Cotesia urabae Austin & Allen (Hymenoptera: Braconidae)?

“…In this study M. pulchricornis did not probe U. lugens larvae in the presence of C. urabae , and achieved only 5.7% parasitism in the absence of C. urabae , suggesting U. lugens is not an optimal host for this species, as was found by Mansfield et al . (2005).…”

“…In New Zealand, U. lugens is attacked by the larval parasitoid Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae), and four pupal parasitoids ( Anacis sp., Ecthromorpha intricatoria (Fabricius), Xanthopimpla rhopaloceros (Krieger) (Hymenoptera: Ichneumonidae) and Dibrachys sp. (Hymenoptera: Pteromalidae)) (Mansfield et al . 2005; Berndt & Allen 2010).…”

“…2005; Berndt & Allen 2010). As both C. urabae and M. pulchricornis attack similar larval stages of U. lugens , there is a risk that competition between the species will compromise the success of C. urabae as a biological control agent for U. lugens (Mansfield et al . 2005).…”

“…It was first found in New Zealand in 1997 where it was accidentally introduced (Berry 1997). It is now known from at least 22 host species in nine families in that country (Berry & Walker 2004; Mansfield et al . 2005).…”

Biology and pest status of Uraba lugens Walker (Lepidoptera: Nolidae) in Australia and New Zealand

“…Mansfield et al . (2005) recorded one larval parasitoid ( Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae) and two pupal parasitoids ( Xanthopimpla rhopaloceros Krieger and Anacis sp.…”