Community of insects fit phages and natural enemies associated with the cultivation of Amaranthus hypochondriacus L. in the central region of C rdoba (Argentina)

Abstract

Entre las principales limitaciones para la producción de amaranto, se señalan diversas especies de insectos fitófagos. Se propuso como objetivo aportar al conocimiento de las especies de herbívoros y enemigos naturales asociados a este cultivo, determinando densidad, momentos de aparición y su relación con las etapas fenológicas. En parcelas experimentales de Amaranthus hypochondriacus ubicadas en el Campo Escuela de la Facultad de Ciencias Agropecuarias, Universidad Nacional de Córdoba, se realizaron muestreos semanales, desde emergencia hasta madurez fisiológica del cultivo, durante las campañas agrícolas 2016, 2017 y 2019 para obtener ejemplares de fitófagos y predadores. La comunidad de insectos estuvo conformada por 5 órdenes, 21 familias y 40 especies. Coleoptera mostró la mayor abundancia de ejemplares. Se destacó la importancia de la oruga defoliadora Achyra similalis y de dos especies de barrenadores, Conotrachelus histrio y Aerenea cuadriplagiata, por su presencia y abundancia en la etapa reproductiva del cultivo. A partir de larvas de Lepidoptera, se obtuvieron seis especies de parasitoides (Hymenoptera y Diptera). Principalmente asociados a orugas pequeñas y colonias de pulgones, se registraron además seis especies de predadores (Coleoptera, Hemiptera y Diptera).

Among the main limitations for the production of amaranth, various species of phytophagous insects are pointed out. The objective of this study was to contribute to the knowledge of the herbivore species and its natural enemies associated with this crop, determining density, times of appearance and their relationship with the phenological stages. To obtain specimens of phytophagous and predators, weekly samplings were carried out, from emergence to physiological maturity of the crop in experimental plots of Amaranthus hypochondriacus located in the School Field of the Faculty of Agricultural Sciences, National University of Córdoba in the agricultural campaigns of the years 2016, 2017 and 2019. Parasitoids were obtained from Lepidoptera larvae. The insect community consisted of 5 orders, 21 families and 40 species. Coleoptera showed the highest abundance of specimens. The importance of the defoliating caterpillars Achyra similalis and the two species of borers Conotrachelus histrio and Aerenea quadriplagiata was highlighted due to their presence and abundance in the reproductive stage of the crop. From Lepidoptera larvae, six species of parasitoids (Hymenoptera and Diptera) were obtained. Mainly associated with small caterpillars and colonies of aphids, six species of predators were also recorded (Coleoptera, Hemiptera and Diptera).