ESTÍMULOS FÍSICOS Y QUÍMICOS QUE INTERVIENEN EN LA FIJACIÓN DE LAS NINFAS DE Dactylopius opuntiae

Abstract

Dactylopius opuntiae is considered a pest for nopal (Opuntia ficus-indica) in Mexico and it’s controlled with chemical pesticides. Little is known about the stimuli involved in selection host, of the insect; newly – emerged nymphs craw on the nopal cladodium and identify the best place to insert it stylet. This moment is crucial as once nymphs anchor, thy will stay in that place for the rest of their lives. The objective at this research was to know if different visual (colors and patrons) and tactile stimulus determine where nymphs anchor. And to the test potential of cineole, eugenol, menthol and cochineal extracts under greenhouse conditions. Crawling behavior was not affected however black area or horizontal dotted line painted on the walk where attractive to the nymphs. All substance tested diminished up to 63% the number of nymphs fixed on the cladodiums at 50 days, but only eugenol and menthol reduced significantly the area colonized by the insect 107 days after application.