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Composição química e atividade inseticida do extrato acetônico de Piper alatabaccum Trel & Yuncker (Piperaceae) sobre Hypothenemus hampei Ferrari
(Sociedade Brasileira de Plantas Medicinais, 2013-08-23) Santos, M.R.A.; Lima, R.A.; Silva, A.G.; Teixeira, C.A.D.; Alpirez, I.P.V.; Facundo, V.A.
O presente trabalho teve como objetivo investigar a composição química e avaliar a atividade inseticida do extrato acetônico das raízes de Piper alatabaccum sobre Hypothenemus hampei. As raízes foram coletadas no campus da Universidade Federal de Rondônia, em Porto Velho-RO. Diluições de 100,0, 50,0, 25,0, 5,0 e 0,5 mg mL-1 foram utilizadas para exposição na superfície contaminada e aplicação tópica. No teste de repelência, utilizou-se as diluições de 25,0 e 100,0 mg mL-1. As avaliações ocorreram durante 48 horas após a exposição ao extrato. O extrato foi eficiente na mortalidade em aplicação tópica e superfície contaminada, não sendo eficiente no efeito de repelência. Estes resultados apontam para o elevado potencial inseticida do extrato de P. alatabaccum no controle de H. hampei. Identificou-se cinco compostos, sendo três amidas, dihydropiplartine piperovatina e piplartina, e duas flavona, 3',4',5,5',7 pentamethoxyflavone e 5,5',7-trimetóxi-3',4'-methylenedioxyflavone.
Atrativo para as abelhas Apis mellifera e polinização em café (Coffea arabica L.)
(Faculdade de Medicina Veterinária e Zootecnia / Universidade de São Paulo, 2004-04-29) Malerbo-Souza, Darclet Teresinha; Nogueira-Couto, Regina Helena; Couto, Leoman Almeida; Souza, Julio César de
O presente experimento foi conduzido em Jaboticabal, SP, e teve como objetivos estudar uma cultura de café (Coffea arabica L., var. Mundo Novo), quanto à biologia floral, a freqüência e comportamento dos insetos na flor, testar o produto Bee-HereR (Hoescht Shering Agrevo do Brasil Ltda) quanto a sua atratividade para as abelhas Apis mellifera e verificar a produção de frutos com e sem a visita dos insetos. Para isso, foram verificados o tempo do desenvolvimento e quantidade de açúcar solúvel do néctar das flores; freqüência das visitações dos insetos, no decorrer do dia, por meio de contagem do número de insetos visitando as flores, a cada 60 minutos, das 8 às 17 horas, 10 minutos em cada horário; tempo (em segundos) e tipo de coleta (néctar e/ou pólen) dos insetos mais freqüentes; perda de botões florais; porcentagem de flores que se transformaram em frutos; tempo de formação e contagem dos grãos de café, observando-se a porcentagem de frutificação em flores visitadas ou não pelos insetos. Também foram realizados testes por pulverização utilizando-se o produto Bee-HereR , diluído em xarope e em água, em diferentes horários. A flor durou, em média, cerca de 3 dias desde sua abertura até o murchamento. A quantidade de açúcares do néctar apresentou diferença significativa entre os horários, sendo maior às 8 horas (em média, 102,18 ± 8,75 mg de carboidratos totais por flor). A abelha A. mellifera foi o inseto mais freqüente nas flores de café, coletando, principalmente, néctar no decorrer do dia. A perda de botões florais causada pelas chuvas foi, em média, 26,50 ± 11,70%. O tempo para a formação do fruto foi 6 meses e o número de frutos decorrentes do tratamento descoberto foi maior (38,79% e 168,38%, em 1993 e 1994, respectivamente) que do tratamento coberto. Apesar da eficiência do produto Bee-HereR ser afetada pelas condições climáticas, ele pode ser usado para atrair as abelhas A. mellifera na cultura.
Experimental model for optimizing mechanized mountain coffee harvesting
(Departamento de Engenharia Agrícola - UFCG, 2024-08-30) Souza, Felipe G.; Teixeira, Mauri M.; Villibor, Geice P.; Furtado Júnior, Marconi R.; Cecon, Paulo R.
Coffee holds significant economic and social importance for Brazil, being one of the main commodities in global agribusiness. Coffee growers, particularly those cultivating arabica coffee, face challenges due to labor shortages and high associated costs during manual harvesting. This study aimed to evaluate the operational performance and efficiency of a self-propelled coffee harvester prototype in terraced mountain areas. To assess harvesting losses, efficiency, and operational capacity, the experimental model traversed the designated area entirely. Fruit stripping was performed over the collection system at five different terrain incline angles (8°, 17°, 25°, 30°, and 38°). Harvesting loss was determined by the ratio of the mass of fruits retained by the collection system to the total mass of harvested fruits. For comparison, the efficiency and operational capacity of two workers performing manual fruit harvesting were also measured. Terrain slope did not significantly impact harvesting losses or operational capacity. The highest operational capacity was 0.11 ha h⁻¹, achieved at a 17° slope. The average operational efficiency was 66.2%.
Application rate and hydraulic tips used in remotely piloted aircraft affect the phytosanitary products in coffee plant canopies
(Editora da Universidade Estadual de Maringá - EDUEM, 2024-03-01) Alvarenga, Cleyton Batista de; Zampiróli, Renan; Cunha, João Paulo Arantes Rodrigues da; Rinaldi, Paula Cristina Natalino; Cunha, Bruno Amâncio da; Faria, Layanara Oliveira
Most coffee (Coffea arabica) phytosanitary management techniques are performed using ground-based equipment, and remotely piloted aircraft are a recent alternative. Therefore, this study evaluates the effect of different application rates and hydraulic tips used for spreading phytosanitary products on coffee crops using a remotely piloted aircraft, assisted by artificial targets and dye tracing. The experiment was a 4 × 3 factorial randomized block design with four tips (XR 110-01, TT 110-01, AIXR 110-015, and TTJ60 110-02) and three application rates (8, 12, and 16 L ha-1). Hydrosensitive paper was used to analyze the droplet spectrum, and the Brilliant Blue tracer was used to detect spray deposition. The DJI Agras T20 remotely piloted aircraft was used to apply the phytosanitary product. Speed, flight height, and application range were maintained at 5.56 m s-1, 2 m, and 5 m, respectively. The flight direction was perpendicular to the crop planting lines. The application rate and hydraulic tip jointly controlled the accumulation of droplets on the target according to its position in the plant canopy. Therefore, remotely piloted aircraft can be used in coffee phytosanitary management, particularly to control targets that predominately occur in the upper third of the plant canopy.
Programmed pruning cycle for arabica coffee as enhancer of nutrient cycling to maintain soil fertility
(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2024-12-13) Araújo, Diogo Ribeiro de; Colodetti, Tafarel Victor; Souza, Matheus Fonseca de; Caldeira, Marcos Vinicius Winckler; Oliveira, Fábio Luiz de; Amaral, José Francisco Teixeira do; Maciel, Laiane Silva; Martins, Lima Deleon; Tomaz, Marcelo Antonio
The objective of this work was to evaluate the nutrient cycling and biomass input of arabica coffee plants managed with a programmed pruning cycle and potassium fertilization. The experiment was carried out in a split-plot arrangement, with four doses of K in the plot, and nine periods of evaluation in the subplot. A randomized complete block design with four replicates was applied. Significance was observed as a function of days after pruning, reaching 78.5% of the decomposed leaf material at 324 days. The release of nutrients showed a variable behavior. At 360 days of evaluation, the percentages of releases nutrients were: 97.2, 79.1, 73.7, 68.0, 48.6, and 32.5, for K, P, Mg, Mn, N, and Ca, respectively. Potassium fertilization levels do not influence the decomposition rate of the leaves eliminated by the programmed pruning cycle in arabica coffee.
Morphology of the coffee root system using polyethylene film
(Universidade Federal de Viçosa, 2023-08-25) Nascimento, Letícia Gonçalves do; Assis, Gleice Aparecida de; Fernandes, Marco Iony dos Santos; Caixeta, Lucas Gomes; Carvalho, Fábio Janoni; Mazziero, Beatriz Gallucci
In the initial phase of the coffee crop, the control of weeds and water availability for the establishment of the plants is a concern. The polyethylene cover can positively influence the chemical and biological characteristics of the soil and, consequently, the root system. The objective of this work was to evaluate the morphology of the root system of coffee plants using polyethylene mulching of different widths and colors. Coffee was planted in December 2016 using the cultivar Topázio MG-1190. A randomized repetitions design was used, with four blocks and five treatments, as follows: 1.20-m wide white/black mulching, 1.40-m white/black mulching, 1.20-m silver/black mulching, 1.40-m silver /black mulching, and no mulching. Total root dry matter per soil volume, total root length per soil volume, total root volume per soil volume, total root area per soil volume, specific root surface, specific root length, and mean root diameter were all evaluated. Roots with smaller diameters were concentrated in the 0-0.20 m depth layer, while in the 0.20-0.40 m depth layer, roots with larger diameters were found. Plants grown in 1.20-m silver/black mulching showed a greater surface area and a specific length of the roots.
Mechanized and irrigated coffee cultivation promotes physical subsurface constraints in Oxisols
(Sociedade Brasileira de Ciência do Solo, 2025-06-16) Escobar, Katherine Martinez; Silva, Laís Maria Rodrigues; Morais, Keise Duarte Bacelar de; Neves, Júlio César Lima; Oliveira, Teogenes Senna de
Soils of the Cerrados (Brazilian Savanna) are deep, well-structured, and well-drained, with flat to gently undulating terrain that favors mechanization for coffee cultivation. However, these soils are susceptible to compaction. This study aimed to assess the effect of mechanization on the physical characteristics of an Oxisol under irrigated coffee cultivation in the Alto Paranaíba-Minas Gerais State. We selected eight areas with different cultivars and years of Arabica coffee plantation, sampling five positions: right soil under the tree crown (RSC), right tractor lines (RTL), interrows (IR), left tractor lines (LTL), and left soil under the tree crown (LSC) at layers of 0.00-0.10, 0.10-0.20, 0.20-0.30, and 0.30-0.40 m. We conducted principal component analysis (PCA) and analysis of variance, comparing means through Tukey’s test (p<0.05). The PCA selected three principal components (PC1, PC2, and PC3) composed of 12 physico-chemical properties from a total of 27 evaluated. Total porosity (TP), mean penetration resistance (PRmean), volumetric moisture (θ) at 100 kPa (θ 100 kPa) and 300 kPa (θ 300 kPa) tensions, particle density (PD), and granulometric fractions (clay, fine sand, and coarse sand) were among the most influential attributes. Total porosity and PRmean demonstrated the existence of compaction in the tractor wheel tracks, particularly in the 0.00-0.20 m layer. The 3.5-year-old plantation did not show significant variations in these properties. The θ 100 kPa and θ 300 kPa were higher in the compacted areas, indicating increased water retention but potentially limiting aeration. Clay content increased with depth, while sand fractions decreased, influencing the soil susceptibility to compaction. The vigor of coffee plants, as identified by satellite images (NDVI), could not be fully associated with the physical constraints of the subsurface, as even areas with low vigor did not consistently correlate with poor physical properties in laboratory analyses. These findings highlight the complex interplay between soil physical properties and coffee plant performance, emphasizing the need for comprehensive management strategies in mechanized coffee cultivation.
Development of a mobile application for the sustainable management of coffee
(Escola de Agronomia - UFG, 2025-08-04) Hernández Rodríguez, José Luis; Dávila, José Francisco Ramírez; Cuevas, Rodolfo Serrato; López, Delfina de Jesús Pérez; Jiménez, Federico Benjamín Galacho
The coffee quality has been threatened by phytosanitary and nutritional problems, which have significantly reduced its production and yield. This study aimed to develop a mobile application that allows to create and manage plots using platforms such as Flutter for the front-end and Flask for the back-end, combined with geostatistical techniques to generate semivariograms, kriging and density maps, in order to estimate the spatial distribution and behaviour of a pest, as well as the spatial distribution of the primary macronutrients NPK, so that corrective actions can be taken at the right time, covering specific areas, and reducing environmental impacts, investment costs in fertilizers and pesticides, and helping to increase the coffee yield and quality.
Relations between sensory quality and spectral indices in brazilian arabica coffees
(Academia Brasileira de Ciências, 2025-03-17) SARMENTO, CARLA SIMONE A.G.; LEMOS, ODAIR L.; BOFFO, ELISANGELA F.; MATSUMOTO, SYLVANA N.; CASTRO, INGRID THALIA P. DE; ALVARENGA, YASMIN A.
This article describes an investigation using spectral indices to characterize coffee production of Brazil, regarding beverage quality and possible correlations with the growing environment. The study evaluated 50 arabica coffee samples, 16 of which were natural process, and 34 were pulped coffes. These samples were originated from growing areas located in different altitude ranges and regions of the municipality, with similar planting spacing and predominance of Catuai cultivars. The samples were subjected to sensory analysis, which revealed that 58% of the samples were classified as specialty coffees: 3 natural, and 26 pulped coffes. Multiple correspondence analysis showed that average spectral indices, normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), and photochemical reflectance index (PRI), derived from images of the multispectral instrument (MSI), were not associated with the quality parameters of the coffee beverage. In contrast, the plant senescence reflectance index (PSRI) proved to be the relevant factor in the quality of the drink. In summary, the analysis of the relationship between the indices demonstrated that the NDVI, which measures the vegetative vigor of plants, showed an inverse correlation with the PSRI. Additionally, the principal component analysis suggested that samples collected from drier areas differed significantly from other geographic regions.
Spray deposition from an unmanned aerial vehicle on a coffee crop
(Associação Brasileira de Engenharia Agrícola, 2024-11-29) Cunha, João P. A. R. da; Fonseca, Luciano F. da; Alvarenga, Cleyton B. de; Lopes, Luana de L.; Martins Filho, Rogério M. S.
The use of unmanned aerial vehicles (UAVs) to apply pesticides has grown significantly, but technical data to support improvements in application efficiency are lacking, especially for perennial crops. This study aimed to determine the best operational parameters for the application of pesticides to coffee plants using UAVs. The experiment consisted of 8 treatments and 4 replicates in a 2x2x2 factorial design: two spray mixture compositions (solutions with spreading adjuvant and mineral oil), two spray nozzles (XR flat-fan nozzle and Airmix flat-fan nozzle with air induction) and two spray volumes (10 and 20 L ha-1). Spray solution deposition was evaluated by spectrophotometric detection of a tracer in leaves from the upper and lower parts of the coffee canopy, and spray coverage, droplet density and droplet size were evaluated using water-sensitive paper. The surface tension, pH and electrical conductivity of the solutions were also evaluated. The air induction nozzle was more suitable than the standard nozzle for UAV application, as the former yielded greater deposition of spray solution. Mineral oil improved the spray deposition on the coffee leaves, although the spreader reduced the surface tension to a greater extent. The higher spray volume increased the droplet density, as well as the coverage, which is very relevant, especially whit contact pesticides.

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