Examinando por Materia "Fluctuación poblacional"

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    PublicaciónAcceso abierto
    Abundancia y preferencia trófica de dichotomius belus (coleoptera : scarabaeidae) en la Reserva Forestal de Colosó, Sucre.
    (2011-10-06) Bohórquez Mieles, Juan Carlos; Montoya Lerma, James
    En este estudio se evaluaron la fluctuación poblacional y la preferencia trófica del escarabajo Dichotomius belus. Entre marzo y octubre del 2002, se realizó un muestreo a través de transectos longitudinales en tres hábitats ecológicos (Bosque de galería, Bosque secundario y Potreros) en Colosó, una reserva de bosque seco de la costa norte de Colombia. Los especímenes fueron colectados a partir de muestras separadas de tres tipos de cebos (carne en descomposición y excrementos humano y vacuno) a lo largo de transectos distribuidos en las tres zonas. Un total de 298 individuos fueron colectados entre las épocas seca y lluviosa, pudiendo evidenciar la tendencia que tiene D. belus por los hábitats con presencia de cobertura vegetal. Se observó una correlación entre la abundancia y la precipitación (r = 0.55 > 0.01). En cuanto a la preferencia trófica se encontraron diferencias en la elección de cebos atrayentes por parte de estos individuos, siendo el recurso de mayor preferencia el excremento humano, seguido por carroña y vacuno.
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    PublicaciónAcceso abierto
    Fluctuation of Premnobius cavipennis (Coleoptera: Curculionidae: Scolytinae) populations in balsa (Ochroma pyramidale) plantations in the central zone of the Ecuadorian Littoral.
    (Universidad del Valle, 2021-02-03) Averos, Joselyn Briggite; Castro Olaya, Jessenia; Martínez Chevez, Malena; Guachambala Ando, Marcelino; Peñarrieta Bravo, Soraya; Chirinos Torres, Dorys; García Cruzatti, Luz; Sociedad Colombiana de Entomología - Socolen; Universidad del Valle; Montoya Lerma, James
    This study aimed to determine the population fluctuation of Premnobius cavipennis and the effect of the trap height on balsa plantations (Ochroma pyramidale). The research was in El Vergel, El Empalme, and Guapara, three localities of Ecuador. There were used flight-interception traps with alcohol as an attractant, placed at one, four, and eight meters high. The collection and evaluation were carried out every week, for one year by locality. Premnobius cavipennis showed a population fluctuation throughout the year, with population peaks in months of the rainy season in the three locations. In El Vergel, the greatest abundance of P. cavipennis was found with 2,382 individuals, showing a population maximum in December. In El Empalme 1,263 individuals were captured, with population increases in January and April. In Guapara 525 individuals were registered, showing a population increase in March. There were captured individuals of P. cavipennis in the three heights of the traps in the three locations. There were highly significant differences between the heights, with a greater effect on the capture at one meter in the three locations of individuals at one meter, behavior that was the same in the three locations.
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    PublicaciónAcceso abierto
    Related factors to the Paraleyrodes sp. pos. bondari (Hemiptera: Aleyrodidae) population in avocado.
    (Universidad del Valle, 2016-12-30) Cruz Castiblanco, Ginna Natalia; Varón Devia, Edgar Herney; Quiroga Rojas, Luisa Fernanda; Monje Andrade, Buenaventura; Sierra Baquero, Paola Vanessa; Sociedad Colombiana de Entomología - Socolen; Universidad del Valle
    The severity of the damage caused by the avocado whitefly (Paraleyrodes sp. pos. bondari) and the difficulty to control it, has forced researchers and growers to find alternatives for its management. We investigated the life cycle of the avocado whitefly and the relation of environmental factors with the population of this insect and the presence of its natural enemies in avocado. Biweekly monitoring of ten avocado trees per cultivar (cvs. Hass, Lorena and Choquette) of the percentage of leaf area occupied by whitefly colonies in each of two commercial farms at Fresno (Tolima, Colombia) was conducted during nine months. The climatic variables: rainfall, temperature and relative humidity on each farm were measured on a daily basis. Finally, a quantification and identification of the beneficial fauna associated with the crop was carried out during seven months. The avocado whitefly had a total life cycle of 27.7 ± 0.19 days. Lorena had the highest presence of Paraleyrodes. An inverse correlation between percentage of whitefly incidence in all varieties and relative humidity was observed at La Chiripa farm. Encarsia sp., Eretmocerus sp., and Amitus sp. Were identified as the main potential natural enemies of Paraleyrodes sp. pos. bondari.