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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Selection for frost resistance in Coffea arabica progenies carrying C. liberica var. dewevrei genes(Crop Breeding and Applied Biotechnology, 2005) Petek, Marcos Rafael; Sera, Tumoru; Alteia, Marcos ZorzenonThis research was carried out to estimate the variability and genetic parameters for the development of cultivars more frost resistant in Coffea arabica progenies, carrying C. liberica var. dewevrei genes. There is genetic variability for frost resistance in progenies with C. liberica var. dewevrei genes. The rust resistance, vegetative vigor and yield potential should be considered when developing cultivars adapted to frost occurrence areas. Cultivars with yield precocity such as IAPAR 59, that allows a faster recovery yield after a severe frost, minimizing the damage from the phenomenon. The use of index selection is efficient to select simultaneously progenies with greater frost adaptation, vegetative vigor, rust resistance and yield.Item First report of Aethalion reticulatum (Linnaeus, 1767) (Hemiptera: Aethalionidae) infesting plants of Coffea arabica (Linnaeus, 1753) (Rubiaceae)(Editora UFLA, 2021) Resende, Laís Sousa; Moreira, Luciano Bastos; Carvalho, Vinícius Castro; Carvalho, Geraldo AndradeCoffee has great socio-economic importance, and in this scenario, Brazil stands out as the largest producer and exporter of coffee beans. However, the coffee crop is susceptible to the attack of several insect pests, the main ones being the coffee berry borer Hypothenemus hampei (Coleoptera: Curculionidae: Scolytinae) and the leaf miner Leucoptera coffeella (Lepidoptera: Lyonetiidae), which can cause great economic losses if left unchecked. However, other pest arthropods may be present in the crop, and their identification and evaluation of its importance are essential for the elaboration of mitigation measures. Up to date, the presence of the leafhopper Aethalion reticulatum (Hemiptera: Aethalionidae) in Coffea arabica (Rubiaceae) plants has not been reported in the literature. Thus, the present study aimed to describe the occurrence of A. reticulatum in Coffea arabica plants on the Campus of the Federal University of Lavras (UFLA), Lavras, Minas Gerais, Brazil.Item Effect of the impact of rigid rods on coffee fruit detachment efficiency by mechanical vibrations(Editora UFLA, 2020) Gomes, Ely Queiroz; Santos, Fabio Lúcio; Nascimento, Moysés; Velloso, Nara SilveiraThe mechanization of field activities has been the response of coffee producers to the labor shortage, especially for fruit harvesting. The use of mechanical harvesters allows greater harvesting efficiency and ensures the economic viability of coffee plantations, which currently depend mainly on the reduction in production costs. The principle used for mechanized coffee harvesting is based on the principle of mechanical vibration. The objective of this study was to analyze the dynamic behavior of the coffee fruit-peduncle-branch system under mechanical vibration and the impact of the vibrating rods on the fruit detachment process in association with this behavior. Fragments of coffee branches containing fruits in the unripe and ripe stages were used in this experiment. These samples were subjected to different frequencies (20, 30, 40, and 50 Hz) and amplitudes (0.002, 0.003, and 0.004 m). Another variable analyzed was the form of vibration transmission to the fruits, with the vibrations being transmitted to the samples with or without the impact of the fiberglass rods. The fruit detachment efficiency increased as the ripening stage progressed from unripe to ripe. A higher detachment efficiency occurred with the increase in vibration frequency and amplitude because of the higher vibrational energy imposed on the fruit. The detachment efficiency was low when the vibration was transmitted without the impact of the rods. Conversely, the vibration in combination with impact achieved a mean detachment efficiency of approximately 90%.Item In vivo compatibility between Beauveria bassiana (Bals.) Vuillemin and castor oil on Hypothenemus hampei (Ferrari)(Editora UFLA, 2020) Celestino, Flávio Neves; Pratissoli, Dirceu; Santos Junior, Hugo José Gonçalves dos; Machado, Lorena ContariniThe degree of in vivo compatibility between the entomopathogenic fungi Beauveria bassiana (Bals.) Vuillemin (Ascomycota: Hypocreales) and castor oil is important, as the interaction can be additive, synergistic or antagonistic. Thus, the objective of this study was to evaluate the in vivo compatibility between castor oil and B. bassiana on the coffee berry borer. The CCA-UFES/Bb-4 isolate of B. bassiana was used in concentrations of 0.0 (control), 1 x 104, 1 x 105, 1 x 106 and 1 x 107 conidia mL-1. The concentrations of castor oil were: 0.0 (control), 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0% v v-1. The total and confirmed mortality were evaluated, and data submitted to variance analysis. To verify the effect of B. bassiana and castor oil concentrations, the data were submitted to regression analysis at 5% probability. Castor oil had an antagonistic effect on B. bassiana reducing the mortality of coffee berry borer. The mortality of H. hampei reduced caused by interaction between B. bassiana and castor oil, due to increasing concentration of castor oil. Lower interference of castor oil was observed for high concentrations of B. bassiana. Based on the results, management of H. hampei cannot be normally performed using the association between castor bean oil and B. bassiana, except if the economic viability of the higher concentrations justified.Item Associação de Pseudomonas syringae pv. garcae com algumas características agronômicas em cafeeiros F2 segregantes para o gene erecta(Editora UFLA, 2004-09) Sera, Gustavo Hiroshi; Sera, Tumoru; Altéia, Marcos Zorzenom; Androcioli Filho, Armando; Azevedo, José Alves de; Petek, Marcos Rafael; Ito, Dhalton ShiguerA bacteriose causada pela Pseudomonas syringae pv. garcae provoca grandes prejuízos em algumas regiões da cafei- cultura brasileira, como Paraná, São Paulo e Minas Gerais, principalmente em lavouras novas, podadas e expostas ao vento. Com este trabalho, objetivou-se estudar nas plantas F 2 do cruzamento entre os genótipos IAPAR-59 e Catuaí Erecta a associação entre as características vigor vegetativo e ângulos de inserção das ramificações plagiotrópicas sobre a intensidade de ocorrência da bacteriose. Avaliaram-se, em outubro de 2001, 316 plantas F 2 plantadas no IAPAR de Londrina em outubro de 1998. A escala de notas de avaliação da incidência de bacteriose adotada foi de 1 a 5, sendo 1 = plantas sem lesão e 5 = plantas com muitas lesões. As notas de vigor vegetativo adotadas foram de 1 a 5, sendo 1 para folhas de coloração verde-claras e 5 para folhas verde- escuras. Para a inserção dos ramos plagiotrópicos sobre os ortotrópicos, as notas variaram de 1 a 3, sendo 1 = normal (45 a 70o), 2 = semi-ereta (25 a 40o) e 3 = ereta (5 a 20o). Estimou-se o coeficiente de correlação de Pearson para verificar a associação entre as características vigor vegetativo e do ângulo de inserção das ramificações plagiotrópicas com a intensidade de ocorrência da bacteriose nos cafeeiros. A correlação estimada entre a intensidade da bacteriose com o ângulo de inserção dos ramos plagiotrópicos foi de r = + 0,2087**. Não houve correlação significativa entre a bacteriose e o vigor vegetativo. Assim, plantas com ramificação plagiotrópica ereta são predispostas a uma maior incidência de bacteriose.Item Genetic variability for frost resistance among coffea accessions assessed in the field and in a cold chamber(Instituto de Tecnologia do Paraná - Tecpar, 2005-01) Petek, Marcos Rafael; Sera, Tumoru; Alteia, Marcos ZorzenonThe genetic variability for frost resistance was evaluated in field conditions and cold chamber among Coffea accessions. Results showed that C. liberica var. dewevrei and C. racemosa, as well as hybrids obtained from these species were more resistant to frost. There was a great genetic variability for frost resistance among the evaluated sources (b 2 = 0,98). The correlation estimated between damages in the field and in the cold chamber was 0.933**, therefore, this methodology was efficient and feasible and could be potentially used in a breeding program.Item Resistance to leaf rust in coffee carrying SH3 gene and others SH genes(Instituto de Tecnologia do Paraná - Tecpar, 2007-09) Sera, Gustavo Hiroshi; Sera, Tumoru; Ito, Dhalton Shiguer; Azevedo, José Alves de; Mata, João Siqueira da; Dói, Deisy Saori; Ribeiro Filho, Claudionor; Kanayama, Fabio SeidiThe aim of this work was to evaluate the resistance to rust in coffee carrying SH3 gene and other SH genes. Twenty one CIFC’s coffee trees with several resistance genes SH were evaluated in field conditions. All the evaluated coffees carrying SH3 gene presented resistance to the rust. It was possible that rust races with the virulence gene v3 in the Paraná State didn’t exist. The SH3 gene in combination with genes SH5, SH6, SH7, SH8, SH9 and SH? would be very important to obtain cultivars with more durable resistance to the rust.Item Selection for durable resistance to leaf rust using test-crosses on IAPAR-59 and Tupi IAC 1669-33 cultivars of Coffea arabica(Instituto de Tecnologia do Paraná - Tecpar, 2007-07) Sera, Gustavo Hiroshi; Sera, Tumoru; Ito, Dhalton Shiguer; Azevedo, José Alves de; Mata, João Siqueira da; Doi, Deisy Saori; Ribeiro Filho, ClaudionorThe aim of this study was to identify plants of the IAPAR-59 and Tupi IAC 1669-33 coffee cultivars with less defeated resistance genes by the rust races present at IAPAR (Londrina, Paraná State, Brazil) using test-crosses. Eighteen test-crosses derived from hybridizations between ‘IAPAR-59’ or ‘Tupi IAC 1669-33’ with susceptible coffee to the rust disease were evaluated. Six hybrids were used as susceptible standards originated from hybridizations between two susceptible coffee plants. Many parental plants of the ‘IAPAR-59’ and ‘Tupi IAC 1669- 33’ presented more defeated resistance genes against rust races present at IAPAR than others of these cultivars or the genes were in heterozygous, because of segregant susceptible plants observed in some test-crosses. The test- crosses were very efficient to identify plants with less defeated resistance genes to the H. vastatrix. Coffee plants considered resistants would must be made test-crosses to verify which plants presented less and/or more defeated genes in homozygous.