Acta Scientiarum Agronomy
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Item 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 OliveiraMost 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.Item Genetic parameters and chemical characterization of conilon coffee accessions under irrigation in the Cerrado(Editora da Universidade Estadual de Maringá - EDUEM, 2024-10-25) Brige, Felipe Augusto Alves; Amabile, Renato Fernando; Malaquias, Juaci Vitória; Celestino, Sonia Maria Costa; Fagioli, Marcelo; Delvico, Francisco Marcos dos Santos; Veiga, Adriano Delly; Sala, Pedro Ivo Aquino LeiteThe objective of this study was to identify the genetic, phenotypic and environmental parameters related to chemical compounds associated with beverage quality in a conilon coffee collection, grown in an irrigated system, in the Cerrado. The experiment was carried out at Embrapa Cerrados using green grains harvested in two years from 84 genotypes of the cultivar Robusta Tropical. Caffeine content, protein, ether extract, total soluble solids, pH and titratable acidity were evaluated. The data were subjected to analysis of variance. Significant differences were observed at 1% probability among accessions for all evaluated chemical characteristics in both harvest years. The high heritability, genetic coefficients of variation and selective accuracy reveal the potential for achieving genetic gains via the selection of genotypes adapted to the irrigated system in the Cerrado combined with high beverage quality.Item Modeling nitrogen loss due to ammonia volatilization in fertilizers applied to coffee plants(Editora da Universidade Estadual de Maringá - EDUEM, 2025-03-25) Nascimento, Leonardo de Almeida; Fernandes, Felipe Augusto; Pereira, Adriele Aparecida; Alves, Henrique José de Paula; Fernandes, Tales JesusThe coffee tree has a strong dependence on nitrogen (N), which influences the nutritional aspect and plant productivity. The knowledge of the nutritional behavior of coffee crops, as well as the pattern of nutrient release and loss, contribute to the appropriate crop management, influencing quality, productivity and minimizing economic losses. Therefore, the objective of this article is to select the non-linear model that best describes nitrogen losses due to ammonia (NH3) volatilization, in seven conventional and increased efficiency fertilizers, applied in three installments to coffee plants and indicate the fertilizers that presented the highest and lowest nitrogen losses due to NH3 volatilization. The data come from an experiment carried out during the 2015/2016 harvest at the Coffee Innovation Agency (INOVACAFÉ) of the Federal University of Lavras, in a randomized block design with 3 replications of 7 treatments (nitrogen fertilizers). The estimation method used was the least squares method (MMQ), with the Gauss-Newton convergence algorithm as the iterative method. As diagnostic measures to determine the best model, the adjusted coefficient of determination (R2aj), residual standard deviation (RSD), Akaike information criterion (AIC) and mean absolute deviation (MAD) were used. It was verified that all models exhibited good adjustments, however, the Brody and Logistic models stood out in describing the accumulated nitrogen losses, due to ammonia volatilization, in relation to the seven treatments applied and evaluated. It was found that ammonium nitrate and ammonium sulfate fertilizers presented the lowest N losses, while Prilled Urea and Urea + anionic polymer contribute the greatest losses due to the volatilization of NH3, in the three fertilizations on coffee plants.Item Selection of differentiated maturity genotypes of Coffea canephora(Editora da Universidade Estadual de Maringá - EDUEM, 2025-06-02) Senra, João Felipe de Brites; Silva, Viviane Alexia Correia; Esposti, Marlon Dutra Degli; Ferreira, Adésio; Milheiros, Idalina Sturião; Ramos, Isabela Bolari; Oliveira, Rosana Gomes de; Benevenute, Lorran MarquesThe aim of this study was to select Coffea canephora genotypes from the seminal propagation variety ‘ES8152’ with different harvest times. The experiment was conducted using a Federer augmented block design with three repetitions, evaluating 175 genotypes and four clonal witnesses in two harvests (2022 and 2023), and 20 morphoagronomic characteristics were evaluated. The data were analyzed using the REML/BLUP methodology with the Selegen software, where the variance components and genetic values were estimated. The selection was performed using the Mulamba-Rank index. The bottom sieve (BS) and top sieve (TS) characteristics had high heritability (0.5779 and 0.6694, respectively) and accuracy (0.7602 and 0.8182, respectively). TS also showed high repeatability (0.6827). The genotypic effects were significant at 1% level for days for fruit ripening, fruit size, vegetative vigor, yield per plant, TS, and BS; at 5% level for general scale; and at 10% level for incidence of rust, degree of inclination, and percentage of fruit float. It was possible to distinguish 20 superior genotypes in terms of maturation, among which the selection gains for the genotypic clusters were 46.14, 45.92 and 41.56% for indefinite, early, and late maturation, respectively, by applying a selection intensity of 11.43%. Genotypes 25, 26, 73, 93, and 100 could be used for early maturing varieties, whereas genotypes 155 and 189 could be used for late-maturing varieties. The most promising genotypes for composing a variety, regardless of the maturation period, were 20, 39, 90, 112, and 190, as these were among the five best genotypes ranked in the three selection processes, demonstrating that they added superior desired morphoagronomic characteristics. It is concluded that there is genetic variability among the 175 genotypes evaluated, as well as significant genetic effects to be explored in the pool gene of individuals originating from the 'ES8152' variety.Item Physiological and nutritional parameters of drought resistance in coffee seedlings genotypes(Editora da Universidade Estadual de Maringá - EDUEM, 2025-06-02) Andreazi, Elder; Sousa, Bruno Teixeira de; Oliveira, Halley Caixeta; Fonseca, Inês Cristina de Batista; Mariucci Junior, Valdir; Shigueoka, Luciana Harumi; Sera, Gustavo HiroshiDrought is an environmental condition that compromises the development of coffee plants. New coffee genotypes that are resistant to drought must be selected quickly and practically. The objectives of this study were to evaluate the resistance of five genotypes of Coffea arabica, including three new genotypes with introgression of genes from Coffea racemosa (H0113-40-26-1, H0113-40-26-19, and H0113-40-26-10), to water restriction and relate the intensity of plant wilting with physiological responses and nutrient accumulation. The experiment was conducted using 45 coffee seedlings obtained from seeds with six pairs of leaves cultivated in tubes. Some seedlings were subjected to two water restriction periods, whereas the remainder were kept under irrigation. The photosynthesis rate, transpiration rate, and wilting intensity were evaluated after each restriction period. Nutrient content was also evaluated after two periods of water restriction. The evaluation of wilting intensity corroborated the physiological parameters. There was a reduction in photosynthesis and transpiration rates under water restriction and nutrient accumulation in coffee seedlings H0113-40-26-1, H0113-40-26-19, and H0113-40-26-10 increased under these conditions. C. arabica genotypes carrying the genes of C. racemosa presented good drought resistance, with H0113-40-26-10 being the most resistant and showing the lowest wilt intensity.Item Efficiency of absorption, translocation, and use of nitrogen by water-stressed coffee(Editora da Universidade Estadual de Maringá - EDUEM, 2024) Martinez, Herminia Emilia Prieto; Bohorquez, Cesar Augusto Avellaneda; Cecon, Paulo RobertoClimate change and the expansion of agricultural lands to low-fertility soils have prompted studies on the effects of water and nutritional stress on nutrient uptake and use. This study aimed to evaluate the efficiency of absorption, translocation, and use of N in coffee cultivars under water stress (WS) and different N doses. The experiment was performed hydroponically and arranged in a 4 × 2 × 4 factorial randomized block design with three replications. These factors consisted of four coffee varieties, two N doses, and four levels of WS. At the end of the experiment, the dry matter production, N concentration, and N accumulation of plants, as well as nutritional efficiency indices were evaluated. The data were subjected to analysis of variance and regression. The results showed that in plants previously well-supplied with N, N stress induces greater allocation of dry matter in roots, mitigating the effects of subsequent water deficits on shoot dry matter production. Young Mundo Novo plants subjected to N stress followed by increasing water stress maintained a high utilization efficiency (UE). Young Acauã plants well-supplied with N, maintained their N utilization efficiency up to -1.6 MPa of water stress; however, when they were N starved, they underwent a drastic reduction in UE at potentials below -0.22 MPa.Item 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) Alvarenga, Cleyton Batista de; Zampiróli, Renan; Cunha, João Paulo Arantes Rodrigues da; Rinaldi, Paula Cristina Natalino; Cunha, Bruno Amâncio da; Faria, Layanara OliveiraMost 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.