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Item Seasonal behavior of vegetation determined by sensor on an unmanned aerial vehicle(Academia Brasileira de Ciências, 2021-04-09) Felix, Filipe C.; Avalos, Fabio A.P.; Lima, Wellington De; Cândido, Bernardo M.; Silva, Marx L.N.; Mincato, Ronaldo L.Geographic information systems make it possible to obtain fine scale maps for environmental monitoring from airborne sensors on aerial platforms, such as unmanned aerial vehicles (UAVs), which offer products with low costs and high space-time resolution. The present study assessed the performance of an UAV in the evaluation of the seasonal behavior of five vegetation coverages: Coffea spp., Eucalyptus spp., Pinus spp. and two forest remnants. For this, vegetation indices (Excess Green and Excess Red minus Green), meteorological data and moisture of surface soils were used. In addition, Sentinel-2 satellite images were used to validate these results. The highest correlations with soil moisture were found in coffee and Forest Remnant 1. The Coffea spp. had the indices with the highest correlation to the studied soil properties. However, the UAV images also provided relevant results for understanding the dynamics of forest remnants. The Excess Green index (p = 0.96) had the highest correlation coefficients for Coffea spp., while the Excess Red minus Green index was the best index for forest remnants (p = 0.75). The results confirmed that low-cost UAVs have the potential to be used as a support tool for phenological studies and can also validate satellite-derived data.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 Defense responses to Meloidogyne exigua in resistant coffee cultivar and non-host plant(Sociedade Brasileira de Fitopatologia, 2013) Silva, Rodrigo V.; Oliveira, Rosângela D.L.; Ferreira, Patrícia S.; Ferreira, Aline O.; Rodrigues, Fabrício A.The resistance of coffee plants to Meloidogyne exigua is conferred by the gene Mex-1. However, the mechanisms of resistance still need to be clarified. Therefore, the penetration, development and reproduction of two populations of M. exigua (M1, isolated from the coffee plant and M2, from rubber tree) in susceptible (Coffea arabica ‘Catuai’) and resistant (C. canephora ‘Apoatã’) cultivars were studied. A greater quantity of J2 from M1 penetrated the susceptible cultivar, but there was no difference between the cultivars for M2. Although the resistant coffee cultivar formed some galls, the nematode did not reproduce. M2 did not induce the formation of galls or the production of eggs in either cultivars. Events related to hypersensitive reaction (HR) were observed as well as other defense responses of the coffee cultivar against M. exigua, which inhibited the formation of the feeding site, provoked emigration of the J2 and delayed or inhibited development and reproduction. The response of the non-host plant was more effective, because it did not allow development of the nematode or, consequently, its reproduction. It was concluded that the coffee cultivar’s resistance to M. exigua is not restricted to HR, but rather to a set of defense responses, both constitutive and induced, expressed after nematode penetration, especially phenolic-like compounds.Item Characterization of Meloidogyne incognita populations from São Paulo and Minas Gerais state and their pathogenicity on coffee plants(Sociedade Brasileira de Fitopatologia, 2011) Oliveira, Dagoberto S.; Oliveira, Rosângela D’Arc Lima; Silva, Débora G.; Silva, Rodrigo V.Meloidogyne incognita is one of the most aggressive and harmful plant-parasitic nematodes attacking coffee plantations in Brazil. However, populations from Minas Gerais state (MG) do not incite disease on coffee plants as strongly as populations from São Paulo state (SP). This study aimed to compare the capacity to incite disease on coffee plants from SP and MG-populations based on penetration and post-infective development of second-stage juveniles (J2) stage. Both populations were confirmed as M. incognita by using esterase phenotype I1 and species-specific PCR. Physiologically they were classified as race 2 by differential host test. Susceptible (C. Arabica ‘Catuaí Vermelho IAC 44’) and resistant coffee seedlings (C. canephora ‘Apoatã IAC 2258’) were inoculated with J2 and assessed for penetration and development from 2nd to 40th day after inoculation. Although the penetration rate of the J2 from both populations was higher in susceptible than in resistant seedlings, the SP-population showed a higher penetration than the MG-population for both variables. Post-infective development proceeded only in individuals of the SP-population in susceptible seedlings. The incompatibility between the MG-population and coffee seedlings was evident at the penetration phase, which was also followed by post-penetration resistance factors leading to significant J2 emigration, impeding nematode establishment.Item Escala diagramática para avaliação da severidade da mancha de Phoma do cafeeiro(Sociedade Brasileira de Fitopatologia, 2009) Salgado, Mirian; Pozza, Edson A.; Lima, Luciana Maria de; Pereira, Ricardo T.G.; Pfenning, Ludwig H.Para avaliar a severidade da mancha de Phoma do cafeeiro (Phoma tarda) foi construída uma escala diagramática com oito níveis de severidade. A escala foi então validada por sete avaliadores. Quanto à precisão da escala, os valores de R2 variaram de 0,82 até 0,87 e de 0,85 até 0,94 sem e com o uso da escala, respectivamente. Os erros absolutos médios, severidade real menos a estimada, foram na maioria inferiores a 10%. A escala apresentou boa acurácia com valores estimados de severidade próximos dos valores de severidade real. A reprodutibilidade dos valores estimados por avaliadores foi satisfatória, com valores de R2 superiores a 0,75 em todos os casos. A escala construída e validada pode ser considerada uma boa ferramenta para avaliar a severidade da mancha de Phoma, uma das mais importantesdoenças do cafeeiro.Item Adaptability and stability of Coffea canephora Pierre ex Froehner genotypes in the Western Amazon(Universidade Federal de Santa Maria, 2020) Moraes, Marcos Santana; Rocha, Rodrigo Barros; Teixeira, Alexsandro Lara; Espindula, Marcelo Curitiba; Silva, Camila Andrade; Lunz, Aureny Maria PereiraThe development of Coffea canephora cultivars is based on the characterization of genotype × environment interaction, which is interpreted to quantify the differential behavior of clones at different cultivation sites. The objective of this research was to study the genotype x environment interaction aiming to select clones of broad and specific adaptation to different environments of the Western Amazon. Twelve clones with hybrid characteristics of the botanical varieties Conilon and Robusta and four open pollinated clones, had their performance evaluated in comparison with four controls. The genotype × environment interaction was interpreted based on the environmental quality index, the nonparametric estimator of Lin and Binns, 1988 and on the dispersion of the centroid method. Effects of the genotypes, environment, and genotype × environment interaction were all significant (p<0.01). The environmental quality index (Ij) classified three environments as favorable for coffee production. In terms of the Lin and Binn’s estimator (Pi), hybrid genotypes 16, 10, 13, 09 and 14 presented lower Pi indices than others, and were classified as being more stable. Five clones of low adaptability, seven clones of specific adaptability to favorable or unfavorable environments and two clones of broad adaptability to all environments were identified interpreting the dispersion of the centroid method.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.Item Bioprospecting endophytic bacteria for biological control of coffee leaf rust(Escola Superior de Agricultura "Luiz de Queiroz", 2006-01) Shiomi, Humberto Franco; Silva, Harllen Sandro Alves; Melo, Itamar Soares de; Nunes, Flávia Vieira; Bettiol, WagnerSuppression of plant diseases due to the action of endophytic microorganisms has been demonstrated in several pathosystems. Experiments under controlled conditions involving endophytic bacteria isolated from leaves and branches of Coffea arabica L and Coffea robusta L were conducted with the objective of evaluating the inhibition of germination of Hemileia vastatrix Berk. & Br., race II, urediniospores and the control of coffee leaf rust development in tests with leaf discs, detached leaves, and on potted seedling of cv. Mundo Novo. The endophytic bacterial isolates tested proved to be effective in inhibiting urediniospore germination and/or rust development, with values above 50%, although the results obtained in urediniospore germination tests were inferior to the treatment with fungicide propiconazole. Endophytic isolates TG4-Ia, TF2-IIc, TF9-Ia, TG11-IIa, and TF7-IIa, demonstrated better coffee leaf rust control in leaf discs, detached leaves, and coffee plant tests. The endophytic isolates TG4-Ia and TF9-Ia were identified as Bacillus lentimorbus Dutky and Bacillus cereus Frank. & Frank., respectively. Some endophytic bacterial isolates were effective in controlling the coffee leaf rust, although some increased the severity of the disease. Even though a relatively small number of endophytic bacteria were tested, promising results were obtained regarding the efficiency of coffee leaf rust biocontrol. These selected agents appears to be an alternative for future replacement of chemical fungicide.Item Qualidade da bebida em espécies e populações derivadas de híbridos interespecíficos de Coffea(Instituto Agronômico (IAC), 1990-07) Carvalho, Alcides; Teixeira, Aldir Alves; Fazuoli, Luiz Carlos; Guerreiro Filho, OliveiroAvaliou-se, em dois experimentos, a qualidade da bebida das espécies Coffea canephora e C. congensis e derivados de híbridações interespecíficas [C. canephora duplicado (dp) x C. arabica, C. canephora x C. eugenioides, C. arabica x C. dewevrei dp e C. racemosa x C. arabica]. Por tratar-se de análise de bebida de cafés pouco conhecidos, avaliou-se a eficiência de uma escala de 1 a 10 pontos em comparação à escala de 0 a 5 pontos utilizada para C. arabica. Foram, também, acrescentadas pelos provadores indicações relacionadas ao gosto da bebida. A escala de 6 pontos mostrou-se pouco eficaz na discriminação dos tratamentos e a de 10 pontos, utilizada alternativamente, revelou-se mais eficiente nos dois experimentos. No primeiro, verificou-se, quanto à qualidade, uma superioridade dos grupos C arabica x C. dewevrei dp e C. canephora dp x C. arabica pelas duas escalas. No segundo experimento, o grupo C. racemosa x C. arabica apresentou a maior média, apesar de não diferir, pela escala 1, dos demais grupos. Pela escala 2, superou, no entanto, os grupos C. canephora e C. congensis. Gostos incomuns foram observados nas amostras com relação à bebida. Atribuem-se à grande diversidade do material analisado e a falta de familiarização dos provadores com espécies bem diferentes de C. arabica, certas discrepâncias com relação à determinação desses defeitos nas amostras analisadas.Item Toxicidade do óleo de mamona à broca-do-café [Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae)](Editora UFLA, 2015-07) Celestino, Flávio Neves; Pratissoli, Dirceu; Machado, Lorena Contarini; Costa, Adilson Vidal; Santos Junior, Hugo José Gonçalves dos; Zinger, Fernando DomingoO óleo extraído da semente da mamoneira tem demonstrado ser muito promissor ao controle de insetos-praga. Objetivou-se, neste trabalho, avaliar a eficiência do óleo de duas cultivares de mamona, sob duas formas de aplicação e em sete concentrações para o controle de Hypothenemus hampei (Ferrari). O óleo obtido das cultivares de mamona, IAC 80 e Paraguaçu, foram utilizadas nas concentrações de 0,5; 1,0; 1,5; 2,0; 2,5 e 3,0% (v/v) e o controle (0,0%), em aplicação direta e indireta sobre a broca-do-café. As cultivares de mamona não apresentaram diferença significativa quanto à mortalidade de H. hampei. A aplicação direta do óleo de mamona sobre a broca-do-café provocou maior mortalidade que a aplicação indireta, exceto para a concentração de 0,5% (v/v). O óleo de mamona na concentração de 3,0% (v/v) causou 34,21 e 63,20% de mortalidade para as aplicações indireta e direta, respectivamente. A mortalidade provocada pela aplicação indireta e direta sobre a broca-do-café aumentou em função do aumento da concentração do óleo de mamona. A aplicação direta do óleo de mamona sobre a broca-do-café apresentou CL 50 de 2,05% (v/v).