Revista Ceres
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/9884
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Resultados da Pesquisa
Item Effect of air blast sprayer application speed on the dye retention of coffee leaves(Universidade Federal de Viçosa, 2022-01-09) Alvarenga, Cleyton Batista de; Zampiroli, Renan; Rinaldi, Paula Cristina Natalino; Silva, Tulio Urban Lourenço MirandaImproving the effectiveness of pesticide application for controlling insects, mites, and pathogens in coffee cultivation has been a major challenge for coffee farmers, researchers, and consultants. The present study aimed to assess the deposition and distribution of a brilliant blue tracer in the coffee canopy using Jacto’s Arbus 2000 Super Export EL and Kuhn’s Twister 2000 air blast sprayers at different application speeds (5 and 7 km h-1). The experiment was conducted using a randomized block design, with a 2 × 2 factorial arrangement (two sprayer models and two application speeds), with six replicates. After spraying, leaves were collected, and the deposition of the tracer was assessed using spectrophotometry. The canopy was divided into lower, middle, and upper heights, and subdivided into external and internal crown positions. The percentage difference in spray deposition between positions was termed relative spray deposition. Spray deposition in the internal crown differed only in the upper third section between sprayers. In the external crown, the application speed affected the deposition of tracer dye for both sprayers, whereas, in the internal crown, the application speed only affected the deposition of tracer dye in the upper crown section only when using the Arbus sprayer.Item Combined application of Isaria fumosorosea and beta-cyfluthrin in the control of coffee leaf miner(Universidade Federal de Viçosa, 2022-10-17) Lago, William Oliveira do; Sabino, Paulo Henrique de Siqueira; Ramirio, Lucas Deleon; Venâncio, Helaine Barros de OliveiraThe coffee leaf miner is responsible for significant decreases in coffee production. To mitigate the problems caused by this pest control strategies need to be applied. The combined application of chemical and biological insecticides is an alternative that can reduce the population of leaf miner in areas with high infestation and occurrence of resistant individuals. The objective of this study was to evaluate the combined application of Isaria fumosorosea and beta-cyfluthrin in the control of coffee leaf miner. A randomized block design was used, in a 4 x 2 factorial scheme, with four treatments: I. fumosorosea, beta-cyfluthrin, I fumosorosea + beta-cyfluthrin and control, besides two application levels, one and two applications. There was no significant effect on the interaction between treatments. The number of applications did not increase the control percentage of the leaf miner. However, the treatments I. fumosorosea, beta-cyfluthrin, I fumosorosea + beta-cyfluthrin showed a higher control percentage of the leaf miner, compared to the control treatment with both one and two applications. I. fumosorosea, beta-cyfluthrin, and the combination of I fumosorosea + beta-cyfluthrin are effective in controlling the leaf miner.Item Nematological survey in coffee nursery in Espirito Santo state, Brazil(Universidade Federal de Viçosa, 2021) Scarpi, Maria Cecília Fonseca; Gonçalves, Ângelo Oliveira; Souza, Antônio Fernando de; Camara, Guilherme de Resende; Moraes, Willian Bucker; Alves, Fábio RamosDespite the important role of coffee production in the economy of Espirito Santo, the second largest coffee producing state in Brazil, productivity is still below the Brazilian average. One of the factors that explain this low productivity is the presence of nematodes of the genus Meloidogyne. Contaminated seedlings are an important and efficient agent for disseminating nematodes. According to normative instruction no. 35 (IN 35), of 11/29/2012 of the Ministry of Agriculture, Livestock and Supply (MAPA), the presence of Meloidogyne spp. in a single plant among a field-lot of seedlings condemns it, and the plants that compose that lot should be destroyed. In Espirito Santo, no evaluation has been carried out in nurseries covering the entire State for phytonematode detection. Therefore, the objective of this work was to carry out a nematological survey in nurseries to guide the nurserymen in relation to fulfilling IN 35 of MAPA, in addition to guiding them regarding the phytosanitary care during the production of their seedlings. The nurseries were evaluated in 19 municipalities located in both the north and the south of Espírito Santo. There were Meloidogyne spp. in evaluated samples.Item Effectiveness of coffee leaf miner control associated with spray deposition in coffee leaves(Universidade Federal de Viçosa, 2020) Zampiroli, Renan; Alvarenga, Cleyton Batista de; Rinaldi, Paula Cristina Natalino; Andaló, Vanessa; Prado, Jair Rocha do; Gonçalves, Pablo Arthur SilvaCoffee production faces challenges due to the susceptibility of the crop to insects. Owing to the coffee leaf miner Leucoptera coffeella, which is one of the main insect pests, the technology for the application of phytosanitary measures becomes the main challenge for coffee growers. This study aimed to evaluate the effectiveness of coffee leaf miner control using different methods of application. The study was conducted in an experimental site in the municipality of Monte Carmelo – Minas Gerais. Spray depositions in different positions of the plant canopy and the effective control of coffee leaf miner were evaluated using the following application treatments: a hydropneumatic sprayer with varying spray volumes (200 and 400 L ha-1), two hollow-cone spray nozzles with the presence and absence of agricultural adjuvant, and electrostatic application using a spray volume of 200 L ha-1 with and without spray adjuvant. The addition of an adjuvant to the spray did not influence coffee leaf miner control; in contrast, a spray volume of 200 L ha-1 combined with the application of coarse droplets was efficient in the management of insect pest. The reduction in the rate of the application using coarse droplets increased the operational capacity and reduced spray drift potential.Item Comunidade de parasitóides associada à cultura do café em Piatã, Chapada Diamantina, BA(Universidade Federal de Viçosa, 2010-03) Palma-Santos, Magno Clery da; Pérez-Maluf, RaquelOs himenópteros parasitoides são inimigos naturais de insetos-praga e têm demonstrado eficiência em estratégias de controle, contribuindo para a manutenção do equilíbrio ecológico de agroecossistemas. Esta pesquisa buscou identificar a diversidade de parasitoides associada a culturas de café em Piatã, BA. As coletas foram realizadas com armadilhas Malaise, que permaneceram no campo por sete dias em coletas mensais, de setembro de 2006 a agosto de 2007. Foram coletados 14.669 himenópteros, distribuídos em nove superfamílias, sendo elas Ceraphronoidea, Chalcidoidea, Chrysidoidea, Cynipoidea, Evanioidea, Ichneumonoidea, Mymarommatoidea, Platygastroidea e Proctotrupoidea, e 29 famílias. Coletaram-se 22 famílias constantes e 11 dominantes, destacando-se Ichneumonidae, Braconidae e Scelionidae como mais frequentes, totalizando 50,33% dos indivíduos coletados. As famílias Braconidae, Eulophidae e Bethylidae, indicadas como promissoras em programas de controle biológico no café, foram coletadas ao longo de todo o ciclo fenológico do café.Item Seletividade de acaricidas utilizados em cafeeiro para larvas de crisopídeos(Universidade Federal de Viçosa, 2010-09) Vilela, Michelle; Carvalho, Geraldo Andrade; Carvalho, César Freire; Boas, Matheus Alvarenga Vilas; Leite, Maria Isabella SantosOs crisopídeos são encontrados em agroecossistema cafeeiro alimentando-se de várias pragas. Objetivou-se avaliar a seletividade de acaricidas utilizados na cafeeiculta sobre a biologia de Chrysoperla externa (Hagen, 1861). Os tratamentos foram: testemunha (água), espirodiclofeno (0,12 g i.a./L), fenpropatrina (0,15 e 0,30 g i.a./L), enxofre (4,0 e 8,0 g i.a./L) e abamectina (0,0067 e 0,0225 g i.a./L). Pulverizaram-se os produtos sobre larvas de primeiro, segundo e terceiro instares de C. externa por meio da torre de Potter. Avaliaram-se a duração do instar, sobrevivência das larvas e pupas e viabilidade dos ovos produzidos pelos adultos provenientes das larvas tratadas. Os produtos foram classificados em classes de toxicidade. Fenpropatrina foi nocivo e espirodiclofeno e abamectina foram moderadamente nocivos, necessitando de novos estudos em condições de casa de vegetação e campo para confirmação ou não de suas toxicidades. Em função da baixa toxicidade apresentada pelo enxofre ao predador C. externa, pode ser recomendado em programas de manejo de pragas do cafeeiro visando compatibilizar os métodos químico e biológico por meio dessa espécie de crisopídeo.Item Calcium and potassium contents in nutrient solution on Phoma leaf spot intensity in coffee seedlings(Universidade Federal de Viçosa, 2016-07) Catarino, Aricléia de Moraes; Pozza, Edson Ampélio; Pozza, Adélia Aziz Alexandre; Santos, Leone Stabile dias; Vasco, Gabriel Brandão; Souza, Paulo Estevão deCoffee is one of the main export commodities of Brazilian agribusiness. Phoma leaf spot [Phoma tarda (Stewart) Boerema & Bollen] is one of the most important coffee fungal diseases in Brazil. Therefore, this study aimed to evaluate the intensity of Phoma leaf spot in coffee seedlings supplied with different rates of Ca +2 and K + . The study was conducted under controlled conditions in a growth chamber, at the Department of Phytopathology – UFLA, from February 2010 to December 2011. The assay was repeated twice under the same conditions. The nutrient solutions consisted of five concentrations of K + (3, 4, 5, 6, 7 mmol L -1 ) and Ca +2 (2, 4, 6, 8 and 10 mmol L -1 ). The experiment was arranged in a randomized block design, with 25 treatments and three replicates, with two plants per plot. The areas under incidence progress curve (AUIPC) and severity (AUSPC) were calculated. At the lowest rate of Ca 2+ (2 mmol L - 1 ) and highest K + (6 and 7 mmol L -1 ), approximately, the AUIPC was the smallest. For the AUSPC, the lowest rates of Ca +2 and K + resulted in the lowest severities. Supply of Ca +2 and K + in nutrient solution reduced AUIPC and AUSPC of Phoma leaf spot, and these nutrients can be recommended for the management of the disease.