Feeding preferences of the willow sawfly Nematus oligospilus (Hymenoptera: Tenthredinidae) for commercial Salix clones

LOETTI, V.; RUBIO, A.; BELLOCQ, M.I.

REVISTA DE LA SOCIEDAD ENTOMOLóGICA ARGENTINA

SOCIEDAD ENTOMOLÓGICA ARGENTINA

Lugar: Mendoza; Año: 2012 vol. 71 p. 145 - 150

0373-5680

Nematus oligospilus Förster (Hymenoptera:Tenthredinidae) is a willow sawfly native to the Northern Hemispherewhich became a serious defoliator in willow plantations (Salix spp.) of theSouthern Hemisphere after being introduced in the early 1980´s. Studieson host preferences provide useful information for the development of pestmanagement strategies where the willow sawfly may produce tree damage andeconomic loss. Feeding preferences of N. oligospilus larvae were evaluated inlaboratory trials by simultaneously offering leaves from four willow tree clonescommonly used in commercial plantations in Argentina (Salix babylonica varsacramenta Hortus, Salix nigra Marsch., S. babylonica L. x Salix alba L. 131-27 and Salix matsudana Koidz. x S. alba L. 13-44). Larvae of N. oligospilusfed on leaves from the four clones. However, insects consumed a significantlyhigher proportion of S. babylonica var sacramenta leaves than of leaves from the other clones. Results indicate that all clones used in the trials were palatable to the insect, and that S. babylonica var sacramenta is the preferred host for larval herbivory.