Ciência e Agrotecnologia
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/9885
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Item Arbuscular mycorrhizal fungus on the initial growth and nutrition of Coffea arabica L. genotypes(Editora UFLA, 2019-08) Fonseca, Arley José; Freitas, Ana Flávia de; Carvalho, Gladyston Rodrigues; Carneiro, Marco Aurélio Carbone; Vilela, Diego Júnior Martins; Fassio, Larissa de OliveiraThe benefits of mycorrhization occur with the growth of hyphae in colonized roots by promoting an increase of the contact surface which improves the initial growth due to a better absorption of water and nutrients. The objective was to evaluate the effect of arbuscular mycorrhizal fungus Rhizophagus clarus inoculation over the initial development and nutritional response of six genotypes of Coffea arabica L. Six genotypes of Coffea arabica L. were used (MGS Aranas, H29-1-8-5, Red Catuai IAC 144, IPR 100, Catigua MG2, Paraíso H 419-1) and with arbuscular mycorrhizal fungus - AMF: Rhizophagus clarus and without the application of the fungus. For the production of coffee seedlings, seeds were placed to germinate in plastic trays with sterile sand. After germination, 10 seedlings of each genotype were transferred to 0.120 dm 3 polyethylene tubes with substrate. Then the inoculation of five seedlings of each genotype with the AMF R. Clarus was performed. When the seedlings with and without inoculation with the AMF presented six pairs of leaves they were transplanted to 13-liter pots containing soil (Dystrophic red-yellow latosol). The inoculation favored the initial growth of the coffee plants and its intensity varied according to the genotypes. The genotypes H 29-1-8-5, Red Catuai IAC 144 and Catigua MG 2 were the ones that presented higher shoot dry mass, root dry mass, total dry mass and accumulation of P, in relation to MGS aranãs, Paraiso H 419-1 and IPR 100, so they are the most promising to be inoculated with the arbuscular mycorrhizal fungus.Item Levantamento da qualidade da bebida do café e avaliação do estado nutricional dos cafeeiros do Alto Jequitinhonha, Minas Gerais, através do DRIS(Editora UFLA, 2010-09) Farnezi, Múcio Mágno de Melo; Silva, Enilson de Barros; Guimarães, Paulo Tácito Gontijo; Pinto, Nísia Andrade Villela DessimoniA região do Alto Jequitinhonha tem se apresentado como expressivo parque cafeeiro do estado de Minas Gerais. No entanto, têm-se pouca informação sobre a influência do estado nutricional do cafeeiro sobre a qualidade da bebida juntamente com a produção. Objetivou-se, neste trabalho, foi realizar o levantamento da qualidade da bebida do café (Coffea arabica L.) e avaliar o estado nutricional dos cafeeiros do Alto Jequitinhonha, através do DRIS. Obtiveram-se as produções, as atividades enzimáticas da polifenoloxidase dos grãos de café e os teores foliares dos nutrientes em duas safras (2005 e 2006), para o cálculo do DRIS, com vistas a efetuar o diagnóstico nutricional do cafeeiro. A região do Alto Jequitinhonha apresentou aptidão para produzir cafés de melhor qualidade (bebida “mole”, “apenas mole” e “estritamente mole”), e o melhor estado nutricional das lavouras cafeeiras proporcionou produtividade de grãos de 65,0 sacas ha -1 e qualidade de bebida “mole” e “apenas mole”.Item Compaction caused by mechanized operations in a red-yellow latosol cultivated with coffee over time(Editora UFLA, 2012-07) Martins, Paula Cristina Caruana; Junior, Moacir de Souza Dias; Andrade, Maria Luiza de Carvalho; Guimarães, Paulo Tácito GontijoThe main source of soil structure degradation in coffee plantation is the machinery traffic because these operations may cause soil compaction affecting the crop development. This study aimed to generate the load-bearing capacity models for a Red-Yellow Latosol and to determine through the use of these models the soil susceptibility to compaction of the coffee plantation due to the implantation time and the compaction caused by the machinery traffic on the traffic lines located at the top and bottom of the ground. This study was carried out in the EPAMIG Experimental Farm, located at Três Pontas, MG, in coffee plantations (Coffee arabica L.) with 2, 7, 18 and 33 years of establishment. To obtain the load-bearing capacity models, 12 undisturbed soil samples were randomly collected in the 0-3 cm and 15-18 cm layers in the position between the rows for each establishment time of the coffee plantation. It was also randomly collected 10 undisturbed soil samples for each establishment time of the coffee plantations along the tractor traffic lines located at the top and bottom of the ground. These undisturbed soil samples were used in the uniaxial compression tests. The use of the load-bearing capacity models allow to identify the soil susceptibility to compaction due to the implementation time of the coffee plantation and the compaction caused by the machinery traffic on the traffic lines located at the top and bottom of the ground. The percentage of compacted soil samples increases with the establishment time in the layer of 15-18 cm.Item Load-bearing capacity of a red-yellow latosol cultivated with coffee plants subjected to different weed managements(Editora UFLA, 2013-03) Pais, Paula Sant’Anna Moreira; Dias Junior, Moacir de Souza; Dias, Adriana Cristina; Iori, Piero; Guimarães, Paulo Tácito Gontijo; Santos, Gislene Aparecida dosIt is essential to know the levels of pressure applied to the soil by different weed managements to adapt the management of coffee plantations in a sustainable manner. The objectives of this study were: a) to generate load-bearing capacity models of a Red-Yellow Latosol (Oxisol) submitted to different weed managements and b) to determine which weed management resulted in higher compression. The study was conducted at the Experimental Farm of EPAMIG, located near the community Farias, in Lavras-MG (latitude 21° 14’ 43" S and longitude 44° 59’ 59" W and altitude of 919 m). The soil is a Red-Yellow Latosol (LVA) cultivated with coffee plantation using Topazio MG 1190 coffee variety, since 2006. We evaluated five weed managements, three being through mechanical control (harrow (GD), mowing (RÇ) and brush (TC)) and two by chemical control (post-emergence herbicide (HPos) and pre emergence herbicide (HPre)). To obtain the load-bearing capacity models, 10 undisturbed soil samples were randomly collected in the 0-3, 10-13 and 25-28 cm layers between the rows. The load-bearing capacity models which indicated a higher compaction were: in the 0-3 cm layer, TC and GD; in the 10-13 cm layer, HPre, HPos and RÇ and in the 25-28 cm layer, GD. The load-bearing capacity models that indicated greater susceptibility to compaction were: in the 0-3 cm layer, HPos; in the 10-13 cm layer, GD and TC and in the 25-28 cm layer, HPre.Item Comparison of field and laboratory models of the load bearing capacity in coffee plantations(Editora UFLA, 2013-03) Iori, Piero; Dias Junior, Moacir de Souza; Ajayi, Ayodele Ebenezer; Guimarães, Paulo Tácito Gontijo; Pais, Paula Sant'Anna Moreira; Andrade, Maria Luiza de CarvalhoPrecompression stress is an important property for assessment of tropical soil structure sustainability and is often determined in laboratory tests. The objective of this study was to compare the load bearing capacity models obtained with controlled moisture in laboratory and those obtained with natural field moistures determined a long one year. The evaluation of soil structural sustainability follows four distinct steps: soil sampling in the field, uniaxial compression test of the samples in the laboratory, determination of precompression stress and estimation of the load bearing capacity models. Laboratory estimates of precompression stress were obtained from moisture controlled in laboratory and from natural moisture determined in a field a long one year. In this process, the soil samples were saturated by capillarity with distilled water in laboratory, and after 48 hours, the samples were air dried to obtain the different moisture contents. Then, the precompression stress was determined for this both conditions. To verify if the load bearing capacity models obtained with controlled moisture in laboratory may represent the load bearing models obtained with natural field moisture, these models were compared using the homogeneity test procedure. It was observed that 75% of field models analyzed were similar to the laboratory models. Thus, due to the similarity on the load-bearing capacity models obtained using natural (field) or controlled (laboratory) moisture contents, the assessment of the soil structure sustainability can be done using both methods.Item Water retention and S index of an oxisol subjected to weed control methods in a coffee crop(Editora UFLA, 2014-09) Siqueira, Raphael Henrique da Silva; Ferreira, Mozart Martins; Alcântara, Elifas Nunes de; Silva, Bruno Montoani; Silva, Raphael ComanducciWeed control in different crops affects the chemical, physical, and biological properties of the soil and consequently its structural quality. The objective of this study was to evaluate, using water retention characteristics and the S index, the physical quality of an Oxisol (Red-Yellow Latosol), subjected to weed control during the cultivation of coffee. The following weed control methods were evaluated: harrowing, brushcutting, residue crushing, manual weeding, post-emergence herbicide application, pre- emergence herbicide application, and maintenance of soil cover with peanut forage, Brachiaria grass, and spontaneous vegetation (no weed treatment). The following properties were determined for physical characterization of the soil: bulk density, total porosity, macroporosity, microporosity, water retention, and the S index. The weed control method significantly affected the physical properties and water retention in the subsurface layer of the Oxisol. Soil bulk density, total porosity, macroporosity, and microporosity were significantly correlated with the S index. According to the S index, the physical quality of the soil was classified as very good for the various weed control methods investigated.Item Coffee yield and phosphate nutrition provided to plants by varius phosphorus sources and levels(Editora UFLA, 2015-03) Dias, Kaio Gonçalves de Lima; Furtini Neto, Antônio Eduardo; Guimarães, Paulo Tácito Gontijo; Reis, Thiago Henrique Pereira; Oliveira, Cesar Henrique Caputo dePhosphorus (P) is considered one of the nutrients that most limits crop yields, especially in soils with an advanced degree of weathering. To evaluate P dynamics and availability in soil resulting from various P doses and sources and to assess the resulting P content of coffee leaves and the final coffee yield, an experiment was conducted in the municipality of Três Pontas, MG, Brazil, in a Red Argisol (Ultisol) area. Fertilization, except for P fertilization, was performed based on the soil analysis results. The annual P doses tested were 0, 75, 150, 300, 450 and 600 kg ha-1 P2O5. Two P sources, simple superphosphate and magnesium thermal phosphate, were evaluated and compared in the study. A physicochemical analysis of the soil and an analysis of leaf dry matter were performed. The available P content in the soil increased as a result of the applications of the two sources. The leaf P levels stabilized at approximately 1.8 and 1.9 g kg -1 for simple superphosphate and magnesium thermal phosphate, respectively, as a result of the application of approximately 300 kg ha-1 P2O5 . The coffee responded to P fertilization in the production phase. Averaged over three harvests, the yield per harvest showed gains of 45.3% and 40.3% for simple superphosphate and magnesium thermal phosphate, respectively, with the application of the highest studied dose, 600 kg ha-1 P2O5.Item Genetic diversity in arabica coffee grown in potassium-constrained environment(Editora UFLA, 2015-01) Moura, Waldênia de Melo; Soares, Yaska Janaína Bastos; Amaral Júnior, Antônio Teixeira do; Lima, Paulo César de; Martinez, Hermínia Emília Prieto; Gravina, Geraldo de AmaralPotassium is a source of non-renewable natural resource, and is used in large quantities in coffee fertilization through basically imported formulations in the form of potassium chloride. An alternative to make production systems more sustainable would be obtaining cultivars more efficient in the use of this nutrient. This study aimed to evaluate the genetic diversity among 20 cultivars of coffee, in conditions of low availability of potassium to identify the best combinations for composing future populations to be used in breeding programs. The experiment was arranged in a randomized block design with three replications of nutrient solution. Agronomic characteristics and efficiencies of rooting, absorption, translocation, biomass production and potassium utilization were evaluated. The clustering analysis was based on the unweighted pair group method with arithmetic mean clustering algorithm (UPGMA) and canonical variables. Variability was observed for most treatments. The multivariate procedures produced similar discrimination of genotypes, with the formation of five groups. Hybridizations between the cultivar Icatu Precoce IAC 3283 with cultivars Catuaí Amarelo IAC 62, Araponga MG1, Caturra Vermelho IAC 477, Catuaí Vermelho IAC 15, Rubi MG 1192 and Catucaí 785/15, and between the cultivar Tupi IAC 1669-33 with cultivars Icatu Vermelho IAC 4045, Acaiá Cerrado MG 1474 and Oeiras MG 6851 are the most promising for obtaining segregating populations or heterotic hybrids in breeding programs aiming more efficiency in potassium utilization.Item Ammonia volatilization from blends with stabilized and controlled-released urea in the coffee system(Editora UFLA, 2016-09) Chagas, Wantuir Filipe Teixeira; Guelfi, Douglas Ramos; Caputo, André Luiz Carvalho; Souza, Taylor Lima de; Andrade, André Baldansi; Faquin, ValdemarApplication of stabilized and controlled-release urea blends can reduce the losses of N-NH3 as compared to conventional urea. The aim of this study was to quantify ammonia volatilization from conventional nitrogen fertilizers and blends of urea + (urea + NBPT) + controlled release urea applied in drip irrigated coffee system. The experiment was conducted under field conditions in in a Red Latosol located in Lavras-MG, Brazil. The randomized complete block design with six treatments: Urea = 450 kg ha -1 yr -1 N (100% of the recommended dose) divided in three splittings equal to 150 kg ha -1 N with an interval of 50 days; ammonium nitrate = 450 kg ha -1 yr -1 N (100% of the recommended dose) in three splittings equal to 150 kg ha -1 N with an interval of 50 days; Polyblen Extend ® -100%= 450 kg ha -1 yr -1 (100% of the recommended dose) applied in two splittings, 315 kg ha -1 N in the 1o split and 135 kg ha -1 N in the 2o split; Polyblen Extend ® -70% = 315 kg ha -1 yr -1 N (70% of the recommended dose) in two splittings, 220.5 kg ha -1 N in the 1o split and 94.5 kg ha -1 N in the 2o split; Polyblen Montanha ® -100% = 450 kg ha -1 yr -1 (100% of the recommended dose) in an unique application in the 1o split and Polyblen Montanha ® -70% = 315 kg ha -1 yr -1 N (70% of the recommended dose) at an unique application in the 1o split, with three repetitions. Total accumulated N-NH3 losses followed the decreasing order: Urea (83.2 kg ha -1 N) > Polyblen Extend ® - 100% (60.3 kg ha -1 N) > Polyblen Montanha ® - 100% (46.8 kg ha -1 N) > Polyblen Extend ® - 70% (35.1 kg ha -1 N) > Polyblen Montanha ® - 70% (24.2 kg ha -1 N) > nitrate ammonium (2.0 kg ha -1 N ). The use of Polyblen Montanha ® decreases two splittings compared to conventional sources such as urea and ammonium nitrate, by applying only 70% of the recommended dose without affecting yield and coffee crop nutrition.Item Nitrogen loss by volatilization of nitrogen fertilizers applied to coffee orchard(Editora UFLA, 2016-03) Dominghetti, Anderson William; Guelfi, Douglas Ramos; Guimarães, Rubens José; Caputo, André Luiz Carvalho; Spehar, Carlos Roberto; Faquin, ValdemarAmmonia volatilization (N-NH3) is one of the main pathways of Nitrogen loss reducing nitrogen use efficiency in coffee orchard. This work aimed at quantifying ammonia volatilization (N-NH3) losses from N-sources to be used in coffee plantations fertilization in Brazil. The experiment was conducted in the field on a dystrophic red latosol (Ferralsol in FAO’s classification) at the Coffee Research Sector, University of Lavras, MG, Brazil. The experimental design was of complete randomized blocks with three repetitions of the following treatments: conventional urea, ammonium nitrate and urea + 0.15% Cu and 0.4% B, urea + anionic polymers, urea + elementary sulfur (S 0) + polymers, and urea + plastic resin. These N sources were split into three doses of 150 kg ha -1 and band applied. The N-NH3 losses by volatilization and variations of pH (H2O) were measured, before and after N application. The N-sources contributed to reduce the soil pH, measured after the third nitrogen fertilization. The N-NH3 losses by volatilization (average from three applications) was as follows: urea + anionic polymers (35.8%) > conventional urea (31.2%) = urea + S 0 + polymers (31.0%) > urea + 0.15% Cu + 0.4 % B (25.6%) > urea + plastic resin (8.6%) = ammonium nitrate (1.0%).