Ciência Rural
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/10366
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Resultados da Pesquisa
Item Soil enzymatic activity under coffee cultivation with different water regimes associated to liming and intercropped brachiaria(Universidade Federal de Santa Maria, 2022) Rodrigues, Raquel Nogueira; Reis Junior, Fábio Bueno dos; Lopes, André Alves de Castro; Rocha, Omar Cruz; Guerra, Antônio Fernando; Veiga, Adriano Delly; Mendes, Ieda de CarvalhoThis research evaluated the effects of coffee cultivation with two different water regimes associated or not with liming and the presence/absence of brachiaria as intercrop on the activities of the soil enzymes β-glucosidase, arylsulfatase and acid phosphatase. The study was carried out at the experimental farm of Embrapa Cerrados, using the cultivar IAC 144 (Coffea arabica L.), under a clayey dystrophic Cerrado Oxisol. Two water regimes (WR) were considered, WR1 with irrigation shifts throughout the year and WR3 with controlled water stress, for about 70 days, in the dry season. In each water regime, effects of lime application (with/without) and the presence/absence of brachiaria cultivated between the lines of coffee plants were evaluated. The activities of the enzymes β-glucosidase, arylsulfatase and acid phosphatase were evaluated during the rainy and dry seasons. Liming and intercropped brachiaria positively affected the activities of the three enzymes assessed in this study at varying degrees, depending on season and/or the WR. Our findings evidenced that intercropped brachiaria in coffee rows was the factor that most positively impacted soil enzymes activ ities.Item Parasitism of Meloidogyne exigua races 1 and 2 in coffee plants derived from Timor Hybrid(Universidade Federal de Santa Maria, 2021) Pereira, Antonio Alves; Caixeta, Larissa de Brito; Fatobene, Bárbhara Joana dos Reis; Oliveira, Claudio Marcelo Gonçalves; Gonçalves, Wallace; Guerreiro Filho, OliveiroTo investigate the degree of parasitism of two populations of Meloidogyne exigua, the gall index (GI) and the reproduction factor (RF) of M. exigua races 1 (Est E2) and 2 (Est E1) were analyzed in 47 progenies on F3:4 or F4:5 generation derived from the crossing between Coffea arabica cv. Catuaí Amarelo and Timor Hybrid. C. canephora cv. Apoatã IAC 2258 and C. arabica cv. Catuaí Vermelho IAC 144 were used as resistance and susceptibility checks, respectively. The genotypes that were classified as resistant or susceptible by RF were similarly classified by GI, showing a close relationship between both methodologies. The data also indicated no differences in virulence between the nematode populations, since the progenies showed similar resistance reactions to the M. exigua races 1 and 2. According to GI from the 47 mother plants evaluated, 27 progenies (57.4%) were classified as resistant to M. exigua races 1 and 2, with GI ranging from 0.0 to 1.4 and 20 progenies (42.6%) were susceptible with GI from 2.6 to 4.4. These results showed that most of the evaluated germplasm was very promising in relation to the development of new Arabica coffee cultivars with resistance to M. exigua.Item Ocorrência e distribuição espacial e temporal do coleóptero Naupactus curtus em cafeeiros de Minas Gerais, Brasil(Universidade Federal de Santa Maria, 2010-06) Fernandes, Flávio Lemes; Picanço, Marcelo Coutinho; Ramos, Rodrigo Soares; Benevenute, Jorgiane da Silva; Fernandes, Maria Elisa de SenaNão há registro de Naupactus curtus em Minas Gerais, e as poucas ocorrências em outros Estados brasileiros são escassas de informações acerca da sua distribuição espacial em cafeeiros. Assim, este trabalho tem por objetivos relatar a ocorrência dessa praga em Minas Gerais e estudar a sua distribuição espacial e temporal em quatro lavouras de Coffea arabica, em Ponte Nova e Jaboticatubas. Os insetos foram monitorados mensalmente. N. curtus foi encontrado nessas duas áreas e apresentou maiores densidades nas bordas das lavouras.Item Calli induction in leaf explants of coffee elite genotypes(Universidade Federal de Santa Maria, 2011-03) Rezende, Juliana Costa de; Carvalho, Carlos Henrique Siqueira de; Pasqual, Moacir; Santos, Ana Carolina Ramia; Carvalho, Stephan Malfitano deThree experiments were carried out with the objective of achieving high effectiveness in calli induction from high heterozygosis leaf explants of Coffea arabica through indirect somatic embryogenesis. A randomized-block design in a 2x5 factorial arrangement made up of two media [BOXTEL & BERTHOULY (1996) and TEIXEIRA et al. (2004)] and five C. arabica genotypes were used in the first experiment. In the second experiment the embryogenic calli production potential was evaluated in ten genotypes. Each of them was considered as a treatment. In the third experiment the variations in both 2.4-D (2.5 e 20μM) and 2-iP (2.5 e 20μM) concentrations in TEIXEIRA et al. (2004) medium and secondary media were evaluated. Crops were kept in a growth room under darkness, at 25±2 o C. The medium described by TEIXEIRA et al (2004) was found to be superior when compared to that described by BOXTEL & BERTHOULY (1996) in the 2.2 and 7.2 genotypes. An opposite behavior was noticed in 4.2 genotype, that is, BOXTEL & BERTHOULY (1996) had medium superiority. Both 3.0 and 5.0 genotypes had the same behavior in both media studied, which shows that the somatic embryo production depends on the genotype. Calli induction depends on the 2-iP and 2.4 D ratio. The 20.0μM of 2.4-D and 20.0μM of 2-iP combination caused the highest embryogenic calli induction rate.Item Morphological characteristics and cell viability of coffee plants calli(Universidade Federal de Santa Maria, 2014-04) Pádua, Marlúcia Souza; Paiva, Luciano Vilela; Silva, Luciano Coutinho da; Livramento, Kalynka Gabriella do; Alves, Eduardo; Castro, Ana Hortência FonsecaThe a im of this research was to characterize and compare two types of calli from leaf explants of Coffea arabica (cultivar Catiguá). Cells of different types of callus were successfully characterized regarding viability and internal and external morphological characteristics. It was obtained two morphologically distinct types of callus: (i) yellow friable and (ii) transparent watery. The yellow friable calli showed higher cell viability and embryogenic characteristics. Scanning and transmission electron microscopy showed embryogenic characteristics in cells of the yellow friable calli evidenced by the presence of small and isodiametric cells, while transparent watery calli showed elongated cells and large cytoplasm vacuolization.Item Consorciação e manejo de Brachiaria decumbens em mudas de cafeeiros infestados com Pratylenchus brachyurus em condições de casa de vegetação(Universidade Federal de Santa Maria, 2015-11) Kubo, Roberto Kazuhiro; Eulalio, Juliana; Oliveira, Claudio Marcelo Gonçalves deCom o objetivo de avaliar o efeito da consorciação e manejo de Brachiaria decumbens cv. ‘Basilisk’ em cafeeiro (Coffea arabica cv. ‘Catuaí Vermelho’) infestado por Pratylenchus brachyurus (Pb), o presente experimento foi desenvolvido em condições de casa de vegetação. Os tratamentos utilizados, com cinco repetições, foram: 1. Café não inoculado no limpo; 2. Café não inoculado consorciado com B. decumbens; 3. Café inoculado com 5000 juvenis e adultos de Pb por vaso (10L), no limpo; 4. Café inoculado com Pb consorciado com B. decumbens podadas semanalmente; 5. Café inoculado com Pb consorciado com B. decumbens com aplicação do herbicida glifosato. Aos 3, 4, 7, 10 e 11 meses após transplante dos cafeeiros, houve um aumento significativo na altura das plantas de cafeeiro sem nematoide mantidas no limpo, comparadas com os tratamentos com cafeeiros em solo infestado com Pb consorciado com B. decumbens podadas e café em solo infestado com Pb consorciado com B. decumbens com aplicação de glifosato. Na avaliação final, realizada 278 dias após à inoculação das plantas, o peso da matéria seca da parte aérea nos tratamentos com Pb consorciado com braquiária e com aplicação de glifosato apresentaram menores valores, quando comparado com a testemunha sem nematoide e sem plantas consorciadas. Com relação ao peso da matéria fresca das raízes, todos os tratamentos foram significativamente mais baixos do que a testemunha sem nematoide e sem consorciação. A população final de P. brachyurus nas raízes foi maior quando o café foi consorciado com braquiária.Item Double sigmoidal models describing the growth of coffee berries(Universidade Federal de Santa Maria, 2017-08) Fernandes, Tales Jesus; Pereira, Adriele Aparecida; Muniz, Joel AugustoThis study aimed to verify if the growth pattern of coffee berries, considering fresh mass accumulation over time, is double sigmoid and to select the most suitable nonlinear model to describe such behavior. Data used consisted of fourteen longitudinal observations of average fresh mass of coffee berries obtained in an experiment with the cultivar Obatã IAC 1669-20. The fits provided by the Logistic and Gompertz models were compared in their single and double versions. Parameters were estimated using the least squares method using the Gauss-Newton algorithm implemented in the nls function of the R software. It can be concluded that the growth pattern of the coffee fruit, in fresh mass accumulation, is double sigmoid. The double Gompertz and double Logistic models were adequate to describe such a growth curve, with a superiority of the double Logistic model.Item Adaptabilidade e estabilidade de genótipos de café no cultivo orgânico em Minas Gerais(Universidade Federal de Santa Maria, 2014-11) Moura, Waldênia de Melo; Lima, Paulo César de; Lopes, Vanessa Schiavon; Carvalho, Cássio Francisco Moreira de; Cruz, Cosme Damião; Oliveira, Ana Maria Cruz eEste trabalho teve como objetivo comparar a adaptabilidade e estabilidade de cultivares de café quanto à média de produtividade anual e de biênios, pelo método de EBERHART & RUSSEL (1996), e selecionar cultivares de café para o cultivo orgânico em Minas Gerais. Os experimentos foram conduzidos em três locais, em delineamento de blocos casualizados com trinta genótipos e três repetições. Uma análise se baseou na produtividade média anual de quatro colheitas (2005/2006, 2006/2007, 2007/2008 e 2008/2009) com o total de doze ambientes. A outra análise considerou a média de dois biênios (2005/2006 e 2006/2007; 2007/2008 e 2008/2009) com o total de seis ambientes. A análise em que se considerou a média da produtividade do biênio apresentou redução expressiva do coefi ciente de variação ambiental. Por isso, foi possível identifi car mais cultivares com adaptabilidade e estabilidade para o cultivo orgânico. Conclui- se que a análise de adaptabilidade e estabilidade com base na produtividade de biênio é mais segura para a seleção de cultivares. Considerando essa premissa, as cultivares ‘Catucaí Vermelho 36/6’, ‘Catuaí Vermelho IAC 15’ e ‘Siriema 842’ são indicadas somente para os ambientes favoráveis. As cultivares ‘Sabiá 708’, ‘IBC Palma 1’, ‘Catucaí Amarelo 24/137’, ‘Oeiras MG 6851’ e as linhagens H518 e H514 são indicadas para o cultivo orgânico em locais com ambientes similares aos avaliados em Minas Gerais.