Ecology and behaviour of Megarhyssa nortoni, a parasitoid used as biological control agent against the invasive woodwasp Sirex noctilio

MARTÍNEZ, ANDRÉS S.; CORLEY JUAN; DEBORAH FISCHBEIN; VILLACIDE JOSE; LANTSCHNER, MARÍA VICTORIA

Curitiba

Congreso; XXV IUFRO World Congress ? IUFRO 2019.; 2019

IUFRO

The introduction of parasitoids in classical biological control programs is a key management method deployed against exotic pests in long-lived crops such as plantation forestry. Sirex noctilio is a pest of cultivated pines, for which several parasitoids, including the wasp Megrahyssa nortoni, have been released in the invaded range. Here, we examine some aspects of M. nortoni that can help explain the parasitoid performance as biocontrol agent: (1) climate matching and the climatic factors that best explain current parasitoid distribution in the Southern Hemisphere; (2) interindividual and sex differences in flight performance, in addition to the cost of flight on longevity and; (3) host location ability as mediated by chemical cues while foraging for hosts. Megarhyssa nortoni established well in regions with temperate and cold climates as eco-climatic models predicted. Particularly, parasitoid distribution constrains to regions with maximum temperature of the warmest month (< 32°C) and minimum temperature of the coldest month (> -21°C). Flight performance was gender-specific: females flew greater distances than males in flight mills and also lived longer. Also, flight did not impact on post-flight longevity for any sex. Females discriminated the odors of infested wood from those of healthy trees and some pine trees over other. In the context of classical biological control studies on established cases allow identifying key attributes. We show that climate matching is necessary to predict establishment success and that knowledge of sex-specific life-history strategies and on the infochemicals use to locate hosts is likely crucial for improving introduction and impact success.