UFV - Teses
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/4
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Item Varronia curassavica Jacq. (Boraginaceae) as an agroecological tool for coffee pest management(Universidade Federal de Viçosa, 2022-08-04) Andrade, Fernanda Pereira; Venzon, Madelaine; Fonseca, Maira Christina Marques; Pallini Filho, AngeloCoffee (Coffea sp.) is a crop of great relevance in agriculture. However, its productivity can be severely affected by the attack of pests, such as Leucoptera coffeella and Hypothenemus hampei. The coffee leaf miner, L. coffeella, is a key coffee pest in the Neotropics. The larvae feed on the parenchyma of coffee leaves decreasing the photosynthesis capacity and leading to significant losses in yield. The coffee berry borer, H. hampei, is the most damaging insect pest of coffee worldwide. This pest lives inside the coffee berry consuming the seeds thus reducing the quantity and quality of the coffee grains. The most common method of control to both pests is the use of synthetic pesticides, which have a low effectiveness due to the selection of resistant populations. Additionally, the excessive use of these products could have a severe impact in the environment and non-target individuals. An alternative for the management of these pests could be the use of specific plants and their secondary metabolites, such as the essential oils. Varronia curassavica is a medicinal species that produces an essential oil with a range of biological activities besides attracting natural enemies, such as the Chrysopidae. The specie Chrysoperla externa is an important biological control agent of a variety of pests, including L. coffeella and H. hampei. In this study, I investigate whether V. curassavica can be used in the management of L. coffeella and H. hampei and benefit their natural enemy C. externa. I performed a greenhouse experiment to evaluate if the association of V. curassavica plants with coffee plants would affect the oviposition of L. coffeella and its predator C. externa (Chapter I). The association of the V. curassavica plants with coffee plants didn’t affect L. coffeella oviposition, however, it increased the C. externa oviposition. I also investigate the effects of the V. curassavica essential oil in the oviposition and the development of eggs and mines of L. coffeella (Chapter II). The V. curassavica essential oil inhibited the oviposition of L. coffeella but did not affect the development of its eggs and mines. I evaluated the lethal and sublethal effects of V. curassavica essential oil on H. hampei, assessing the mortality rates, the mobility of H. hampei, and the repellence of the essential oil to this pest (Chapter III). The essential oil of V. curassavica is toxic to H. hampei and affects its mobility, but it wasn’t repellent to the pest in the concentration tested. This study demonstrates that V. curassavica plant and its essential oil could be a safer alternative in the management of the key coffee pests. Keywords: Coffea sp. Leucoptera coffeella. Hypothenemus hampei. Chrysoperla externa.Item Role of green lacewings and ants on coffee berry borer predation(Universidade Federal de Viçosa, 2021-07-30) Botti, Jéssica Mayara Coffler; Venzon, Madelaine; Araújo, Gustavo Júnior de; Siqueira, Maria Augusta LimaThe coffee berry borer (CBB) Hypothenemus hampei is the most severe pest of the coffee crop in the world. Larvae open galleries inside the endosperm of coffee fruits, causing significant losses in yield and fruits quality. In addition, control of this pest is hampered due to its cryptic habit of living inside the fruits. The reduction the sources of shelter and alternative food for predatory insects that carry out the biological control of CBB is due to the simplification of the landscape associated with conventional coffee crops. Therefore, it is necessary to use measures that aim to decrease these problems caused by the implantation of conventional crops, in order to increase and maintain the CBB natural enemies in these areas. Among these measures, landscape diversification, through strategic diversification with plants that can provide food resources and shelter to natural enemies. In this work, a strategic diversification in coffee crops was implemented, without the use of pesticides, associated with Inga edulis, Varronia currasavica, Senna macranthera and non-crop plants, recognized for favoring the biological control of CBB through the maintenance of predatory ants in the area. During field evaluations, an adult of the Chrysopidae family was found that emerged from a coffee bored berries collected in the diversified coffee crop area. In Chapter I, I confirmed the hypothesis that naked larvae the of Chrysoperla externa are able to enter the galleries and remove CBB eggs and larvae from inside the fruits, proving to be efficient in pest control. In Chapter II, I tested whether the behavior of transporting debris on the back reduces the access to the CBB galleries by trash-carry larvae of Ceraeochrysa cubana in relation to C. externa. The results showed that the first instar larvae of the two species (C. externa and C. cubana) are able to enter the CBB galleries and survive longer in the presence of coffee bored berries than in the presence of healthy berries and without food. However, C. cubana was less efficient in entering the galleries, showing that the trash can limit the predation of CBB inside the fruit. Third instar larvae of C. externa preyed on CBB adults and reduced the capacity of CBB to infest the fruits by 10%, which shows that C. externa can be more efficient in controlling the CBB due to its ease of accessing the galleries. In the Chapter III I evaluated the richness and abundance of predatory ants of CBB, the rate of infestation of CBB and the coffee yield in the diversified system implemented, comparing it to the conventional coffee system. The results showed that strategic diversification increased predator ant richness and abundance, decreased CBB infestation and did not affect coffee yield. Therefore, strategic diversification with I. edulis, V. currasavica, S. macranthera and non-crop plants increases the natural control of CBB by predatory ants and green lacewings, in addition to not reducing coffee yield