title: [Phagodeterrent and systemic activity of a fomulation derived from an extract of common rue (Ruta chalepensis, Rutaceae) on Hypsipyla grandella (Lepidoptera: Pyralidae) larvae].
abstract: A key neotropical pest of mahoganies (Swietenia spp.) and cedars (Cedrela spp.), the larva of Hypsipyla grandella (Zeller) commonly bores into the main shoot of these valuable timber species, causing forking of the stems. Therefore, it would be desirable to count upon a phagodeterrent and systemic product which could readily protect young tissues. Since crude extracts of common rue foliage (Ruta chalepensis L.) have phagodeterrent activity on H. grandella larva, a product was formulated by combining such an extract with a number of coadjuvants, and was assessed on 75-100 cm tall Spanish cedar (Cedrela odorata L.) trees, inside a greenhouse. A completely randomized design was used, with 10 trees per each one of the following treatments: the formulated product, an absolute control (distilled water), a relative control (carbofuran, 1%m/v in water), and the relative control without the crude extract. Number of attacks to the main shoot, fallen leaves and frass piles were recorded, as well as tunnel length. Regarding these variables, the formulated product provided excellent protection to treated trees, with only 0.1 attacks to the main shoot, on the average, at the end of the evaluation period. Likewise, when the systemic activity of the crude extract was assessed, substances present in it were able to translocate and get assimilated by the trees, thereafter causing phagodeterrence to larvae. Finally, an espectrophotometry analysis (performed at a wavelength of 355 nm) allowed us to determine the concentration (403+/-1 mg/l) and percentage (0.40%) of the flavonoid rutin in the crude extract, which eventually may be used as an analytical marker compound, should an industrial formulation be developed.
authors.affiliation: Escuela de Química, Universidad Nacional, Heredia, Costa Rica. titobazu@gmail.com
authors.forename: Javier
authors.initials: J
authors.lastname: Barboza
authors.forename: Luko
authors.initials: L
authors.lastname: Hilje
authors.forename: Julio
authors.initials: J
authors.lastname: Durón
authors.forename: Víctor
authors.initials: V
authors.lastname: Cartín
authors.forename: Marco A
authors.initials: MA
authors.lastname: Calvo
mesh_terms: D000818:Animals; D005247:Feeding Behavior / Q000187:drug effects*; D007814:Larva / Q000187:drug effects; D007915:Lepidoptera / Q000187:drug effects*; D010936:Plant Extracts / Q000494:pharmacology*; D032105:Ruta / Q000737:chemistry*; D013997:Time Factors
chemical_list: D010936:Plant Extracts