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We examined changes in the phlebotomine fauna resulting from human intervention in a tropical dry forest of Northern Colombia where visceral and cutaneous leishmaniases are endemic. A natural forest reserve (Colosó) and a highly degraded area (San Andrés de Sotavento [SAS]) were sampled monthly for 8 mo using Shannon traps, sticky traps, and resting-site collections. Overall abundances were higher in Colosó (15,988) than in SAS (2,324). and species richness of phlebotomines was greater in the forest reserve (11 species) than in the degraded habitat (seven species). Fisher alpha, a measure of diversity, reinforced this trend. Both sand fly communities were dominated by Lutzomyia evansi (Nuòez-Tovar), vector of Leishmania chagasi (Cunha & Chagas), representing 92 and 81% of all captures in Colosó and SAS, respectively. Lutzomyia longipalpis (Lutz & Neiva), the common vector of visceral leishmaniasis, accounted for 4-7% of the sand fly community. Lutzornyia panamensis (Shannon) and Lutzomya gomezi (Nitzulescu), putative vectors of Leishmania braziliensis (Vianna), had low abundances at both study sites. The zoophilic species Lutzomyia cayennensis (Floch & Abonneuc) and Lutzomyia trinidadensis (Newstead) were present in variable numbers according to trapping methods and site. Habitat degradation negatively affected sand fly communities, but medically important species were able to exploit modified environments, thereby contributing to Lishmania endemicity.

Previous studies have shown the sandfly Lutzomyia evansi to be the vector of Leishmania chagasi in northern Colombia. A longitudinal survey during seven months on the host preference of Lutzomyia evansi was conducted in the visceral leishmaniasis focus of San Andrés de Sotavento, Colombia. Host preference was determined by presenting sandflies with a choice of three baits (human, and the reservoirs dog and opossum) and a blank control in specially designed cone traps. A rotational experimental design involved 56 trap nights in which the effect of bait, proximity to forest and season could be distinguished from the potentially confounding factors of site and day to day variation. From a total of 598 sandflies caught during all experiments, females and males of Lutzomyia evansi accounted for 93.8% of the captures in the baited traps. Overall, human attracted the greatest number of sand flies, followed by the other two baits. Attraction and feeding success showed significant differences (P < 0.0001) between baits.

Genetic diversity among three field populations of

Emergent and potentially invasive weevils are a permanent threat to the survival of palm plantations. Hence, understanding the role of emergent pests may be key for preventing future phytosanitary emergencies. In the present study, the role of Rhynchophorus palmarum L. and Dynamis borassi F. (both Coleoptera: Curculionidae) as main causative agents of the peach palm (Bactris gasipaes Kunth; Arecaceae) crown toppling problem were investigated, and the damage was described in 36 farms in the principal production areas of Colombia. A management strategy with the use of 2 pheromones (Rhynchophorol and Ferrolure) in 2 production areas also was evaluated. In total, 4,098 palms were examined from Nov 2017 to Feb 2019. Visible damage oscillated between 0 to 70% of palms affected and was highest on the Pacific coast. Larvae of D. borassi were found exclusively in the inflorescences suggesting that it initiates the damage. Meanwhile, adults of D. borassi and all stages of R. palmarum were recovered from stem damages. Also, new reports of damage were confirmed at the southern Pacific coast, the Andes, and the Amazon region. A total of 8,239 D. borassi and 2,886 R. palmarum were captured in pheromone traps for 14 mo on the Pacific coast. The traps baited with Ferrolure + Rhynchophorol captured a greater number of D. borassi specimens. The data strongly confirm the central role of D. borassi in peach palm damage. Therefore, it is recommended strongly that pheromones be used to prevent further spread of this pest in other countries of this region and to protect palm industries.

RESUMENLas larvas y adultos de varias especies de Astaena dañan las raíces y el follaje de cultivos en climas templados y fríos en Colombia. En el presente artículo se describen la larva de tercer estadio y la pupa de macho y hembra de Astaena valida Burm., se ilustran sus caracteres diagnósticos y se propone una clave para distinguir sus larvas de otros Melolonthinae locales. Se confirmó que las larvas son rizófagas, y se encuentran en grupos de hasta 36 ejemplares/m 2 , prosperan en suelos disfuncionales, asociados a la rizósfera de yuca, pastos, cafeto, fique, tomate, piña, espárragos, maíz y ornamentales. Los adultos son fototáxicos, estacionales, activos en el período de lluvias de octubre y noviembre. Palabras Clave: Escarabajos, Astaena, rizófagos, larvas, Colombia. ABSTRACTLarvae and adults of some species of the genus Astaena may damage the roots and leaves of cultivated plants in the temperate and cold climates in Colombia. The third instar larva as well as male and female pupae of Astaena valida Burm. are described and illustrated. An identification key for the larvae of some genera of Colombian Melolonthinae is included. Larvae of A. valida live in disfunctional soils feeding on roots of yucca, grass, coffee, fique, tomato, pineapple, asparagous, maize and ornamental plants, with densities up to 36 grubs/m 2 . Adults have seasonal activity during October-November rainfall period, and are attracted to electric lights.

No abstract

-Bemisia tabaci (Gennadius) is one of the most important pests of cassava in Africa and several countries of Asia due to the damage caused by direct feeding, the excretion of honeydew, and its capacity as a vector of cassava mosaic geminivirus. There is a general consensus that B. tabaci is a complex of morphologically indistinguishable populations with different biotypes. In the Americas, the polyphagous biotype B does not appear to feed on cassava. Recent studies indicate that it is possible, however, for biotype B to gradually adapt to cassava using phylogenetically related hosts. Therefore, the possibility that some wild species of cassava constitute intermediate hosts in the adaptation process may lead to the establishment of biotype B on commercial varieties of Manihot esculenta. In here, we evaluated Jatropha gossypiifolia, two wild species of cassava (Manihot fl abellifolia and M. carthaginensis) and a commercial cassava variety (MCol 2063) as hosts of biotype B. The highest oviposition rate (2.7 eggs /two days) occurred on M. esculenta, although the development time (44 d) was the longest when compared to M. carthaginensis and J. gossypiifolia. About 60% of the population could reproduce on the wild cassava species vs. 55% on J. gossypiifolia and 27.5% on the commercial variety. Our data suggest that J. gossypiifolia is a suitable host and the wild species M. carthaginensis can constitute a potential intermediate host in the adaptation of biotype B to commercial varieties of cassava.