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

LOETTI V.; ALEJANDRA RUBIO; 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 Hemisphere which became a serious defoliator in willow plantations (Salix spp.) ofthe Southern Hemisphere after being introduced in the early 1980´s. Studies on host preferences provide useful information for the development of pest management strategies where the willow sawfly may produce tree damage and economic loss. Feeding preferences of N. oligospilus larvae were evaluated in laboratory trials by simultaneously offering leaves from four willow tree clones commonly used in commercial plantations in Argentina (Salix babylonica var sacramenta 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. oligospilus fed on leaves from the four clones. However, insects consumed a significantly higher 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.