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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Resistance and effect of insecticide-treated coffee berries of different varieties to the penetration of Hypothenemus hampei (Coleoptera: Curculionidae: Scolytinae)(Editora UFLA, 2021) Davi Júnior, Salmo de Melo; Soares, Walyson Silva; Celoto, Fernando Juari; Fernandes, Flávio Lemes; Oliveira, Mariana Martins Fernandes; Botrel, Gabriel Buso BorgesThe control of Hypothenemus hampei, coffee berry borer (CBB) is difficult as the insects infest inside coffee berries and are thus protected from agrochem icals. Coffee varieties with an increased penetration time by H. hampei can help control this pest tends to be exposed insecticide action for long time. Therefore, this study aimed to determine the time taken by H. hampei to entirely penetrate berries of different coffee varieties and whether insecticides have any influence on the penetration time. Thus, twenty five berries of 27 coffee varieties in the green phenological stage were introduced in rubber caps, with the berry crown exposed.. From this experiment, seven varieties were selected for another bioassay, with insecticides being sprayed on the berries. Copulated female H. hampei were released on the berry, and the penetration time was assessed. Finally, a free-choice test to verify H. hampei food preference was performed, using the same seven coffee varieties. The insects took longer to penetrate the Arara, Catuaí Vermelho IAC 144, and Guará coffee-variety berries. Moreover, all coffee varieties treated with the insecticide cyantraniliprole inhibited penetration by H. hampei. Most coffee varieties treated with insecticides showed a prolonged penetration time by H. hampei compared to the same untreated ones, except for the chlorpyrifos insecticide in the Catuaí IAC 144 and IAC 62 varieties. Additionally, H. hampei showed no feeding preference among the different tested coffee varieties.Item Interaction between mealybugs (Pseudococcidae) and coffee plants(Editora UFLA, 2020) Santa-Cecília, Lenira Viana Costa; Silva, Kethullyn HenriqueMealybugs, Planococcus citri (Risso) and Planococcus minor (Maskell) (Hemiptera: Pseudococcidae) are able to colonize several plants, such as coffee (Coffea spp.), where may impair their production. Despite attacking many plants, frequent outbreaks are only found in certain plants. In this work, we tested the hypothesis that P. citri and P. minor show a better performance, i.e., greater longevity and higher reproductive rate, as well as higher survival in a given coffee species and it exists preference for volatiles of certain coffee species. We studied in the laboratory the food preference of these mealybugs through a free choice test and their development and reproduction in Coffea arabica L. cv. Mundo Novo-IAC–379-19 and Coffea canephora (Pierre & Froenher) cv. Conilon 213. The responsiveness of these insects to the volatiles emitted by these coffee plants was analyzed using an olfactometer. The data showed that mealybugs preferred Conilon coffee plants over the Mundo Novo and, despite completing their development in both of them, most of the biological evaluated parameters were affected by the host species. In the olfactometer assays, the volatiles emitted by the coffee plants cv. Mundo Novo and Conilon were equally attractive to these mealybugs. It is concluded that, although there is no discrimination of odors between coffee plants, Mundo Novo and Conilon, both species of mealybugs show food preference for Conilon, having their development and reproduction favored in these plants.