Manejo integrado de pulgones en cultivos hortícolas al aire libre

Abstract

[EN] Aphids are a serious problem in vegetables, as make cosmetic damages that cause commercial depreciation of the attacked plant, also they are vector s of viral diseases. The control of aphids is relatively easy in conventional agriculture, in contrast, there aren’t effective products against aphids in ecological agriculture. That is the reason why it should be considered a control strategy based in pr eventive measures instead of the therapy. Different sampling methods for estimating aphid populations on lettuce crops have been evaluated in present work (visual counting, vacuum sampling and cutting plants in the laboratory). It was determined that the b est one was vacuum sampling. In addition, six species of aphids were identified in the studied crops ( Brachycaudus cardui , Brevicoryne brassicae , Macrosiphum euphorbiae , Myzus persicae , Aphis fabae and Aphis gossypii ). The first two are monophagous species , the rest are polyphagous. Population dynamics of aphids species associated to lettuce crops (red oak leaf and roman) were studied, finding that the first one has bigger population. Assays to determine the efficacy of biological control of aphids by Aphid ius colemani outdoor in zucchini crop, have shown that only Lysiphlebus testaceipes (species that live naturally in the environment) emerged from samples collected. Different species of parasitoids for aphids have been identified: Aphelinus abdominalis, Ap hidius ervi , Diaeretiella rapae y Lysiphlebus testaceipes. In addition, depending on the plant species which the aphids feeded, the parasitoid species which attacked them changed. Also various families of predator species of aphid colonies (Coccinellidae, Syrphidae, Cecidomydiidae y Chrysopidae) were collected. Propylea quattuordecimpunctata was present in all studied crops . Quite a few individuals of aphids with fungi in their cuticle were found, although none of them belongs to entomopathogenic fungi gro up

[ES] Los pulgones son un problema grave en hortalizas de hoja, principalmente porque producen depreciación comercial de las plantas atacadas. El control de pulgones es relativamente fácil en agricultura convencional mientras que en agricultura ecológica la falta de productos con efecto inmediato sobre los pulgones hace que debamos plantear una estrategia de lucha basada en estrategias preventivas más que en la terapia. El primer paso para desarrollar un programa de control biológico basado en la conservación que favorezca la presencia y desarrollo de las especies autóctonas de parasitoides y depredadores de una región determinada, pasa por tener una idea precisa de qué especies están controlando las poblaciones plaga y en qué proporción.

El trabajo que se propone tiene los siguientes objetivos: · Estudio de la dinámica poblacional de las especies de pulgones que afectan a los cultivos hortícolas en otoño y primavera. · Identificar las especies de insectos auxiliares que pueden regular las poblaciones de los pulgones. · Evaluar el grado de control de las medidas que favorecen el control biológico y cultural de los pulgones: o Diversidad espacial y temporal de especies vegetales cultivadas o Manejo de franjas no cultivadas: composición y diseño o Influencia de diferentes acolchados sobre los niveles poblacionales de pulgones