Examinando por Materia "Natural enemy"

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    PublicaciónAcceso abierto
    Bioecology of Epilachna difficilis (Coleoptera: Coccinellidae: Epilachninae) in Central-West of Mexico.
    (Universidad del Valle, 2017-06-30) Garcia Segura, Jonas; Cortez Madrigal, Hipolito; Marin Jarillo, Antonio; Angoa Pérez, Maria Valentina; Sociedad Colombiana de Entomología - Socolen; Universidad del Valle
    Epilachna difficilis was reported for the first time on Bonplandia geminiflora (Polemoniaceae). To study the biological and ecological aspects of this species, samples were taken weekly in 2011 in “La Gloria” Canyon, Sahuayo, Michoacán, México, and complementary studies were conducted in the laboratory. The first occurrence of E. difficilis was observed in mid-August and the last in early December. Defoliation to B. geminiflora ranged from 38.0-98.5 %. Six species of predators, viz., Podisus congrex, Podisus brevispinus, Oplomus dichrous, Oplomus pulcher (Hemiptera: Pentatomidae: Asopinae), Pselliopus nigropictus, and Rocconota sp. (Hemiptera: Reduviidae), were recorded. Temperature and precipitation were positively correlated (r = 0.8 and 0.6, respectively) with higher population peaks. However, E. difficilis showed a wide range of adaptability in different regions and climates where its host plants grow. Under laboratory conditions, five instars were recorded during 25.95 days of larval development; the entire lifecycle was completed in 37.8 ± 1.7 days. Of the five crops species evaluated, only cucumber suffered damage (30.0 %) by adult insects, although all insects died thereafter. This is the first bio-ecological study of E. difficilis. Results may be useful in the biological control of related pests such as E. varivestis.
  • Miniatura
    PublicaciónAcceso abierto
    Predatory activity of Chrysoperla externa (Neuroptera: Chrysopidae) on Macrosiphum euphorbiae (Hemiptera: Aphididae) in Rosa sp. Crop.
    (Universidad del Valle, 2016-06-30) Gamboa, Sergio; Souza, Brígida; Morales, Rubén; Sociedad Colombiana de Entomología - Socolen; Universidad del Valle
    The objectives of this study was to assess the efficiency of third instar larvae of Chrysoperla externa and to quantify its population control on different densities of Macrosiphum euphorbiae aphids on greenhouse rose crops. For 24 hours, the consumption of C. externa on first and second stage nymphs of M. euphorbiae at a predator: prey ratio of 1:10 was evaluated on four different aphid densities. In the second stage, the predatory capacity of C. externa was compared over a period of 31 days on four (40, 80, 120, 160) initial densities of M. euphorbiae, through the weekly release of predator larvae at a predator: prey ratio of 1:10. This experiment showed that C. externa has a greater predatory capacity at higher M. euphorbiae densities. It was also observed that the initial density of aphids did not influence the consumption of C. externa larvae over a 31 day observation period. However the predator kept the population of M. euphorbiae at lower densities on plants where C. externa larvae were released. Nevertheless, the number and frequency of larvae released did not provide complete aphid population control.