Biblioteca do Café
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Item Coffee resistance to the main diseases: leaf rust and coffee berry disease(Sociedade Brasileira de Fisiologia Vegetal, 2006-06-14) Silva, Maria do Céu; Várzea, Victor; Guerra-Guimarães, Leonor; Azinheira, Helena Gil; Fernandez, Diana; Petitot, Anne-Sophie; Bertrand, Benoit; Lashermes, Philippe; Nicole, MichelConsiderable success has been obtained in the use of classical breeding to control economically important plant diseases, such as the coffee leaf rust and the coffee berry disease (CBD). There is a strong consensus that growing genetically resistant varieties is the most appropriate cost effective means of managing plant diseases and is one of the key components of crop improvement. It has also been recognized that a better knowledge of both, the pathogens and the plant defence mechanisms will allow the development of novel approaches to enhance the durability of resistance. After a brief description of concepts in the field of plant disease resistance, we attempt to give a view of the research progress on coffee leaf rust and CBD concerned with the pathogens infection and variability, coffee breeding for resistance and coffee resistance mechanisms.Item Potential of new Coffea arabica cultivars for renewal of Meloidogyne paranaensis infested crop(Instituto Agronômico (IAC), 2025-06-09) Luz, Silvana Ramlow Otto Teixeira da; Teixeira, Lívia Pimenta; Salgado, Sonia Maria de Lima; Andrade, Vinícius Teixeira; Marques, Elizabeth Rosemeire; Botelho, Cesar Elias; Fatobene, Bárbhara Joana dos Reis; Carvalho, Gladyston RodriguesMeloidogyne paranaensis is one of the most damaging species of root-knot nematode to coffee trees. The development of resistant cultivars is crucial to the continuity of cultivation in infested areas. Thus, the aims of this study were to assess the performance of F6:7 progenies derived from the Amphillo germplasm in an infested area and to validate the new Coffea arabica MGS Vereda and MGS Guaiçara cultivars. The Catuaí Amarelo IAC 62 cultivar was used as the susceptible standard, and IPR 100 as the resistance standard. The experiment was conducted in 2018 using a randomized complete block design with four replications and 15 plants per plot. Resistance related and agronomic traits were assessed over four years. The lowest population of M. paranaensis was observed in progenies 88, 44B, and 105 from MGS Guaiçara, MGS Vereda, and IPR 100 cultivars, respectively. The progenies with the lowest population of M. paranaensis, although resistant, were not productive. The new MGS Vereda cultivar stood out in terms of yield and early fruit ripening, with the highest proportion of cherry fruit at harvest and a low incidence of peaberry grain. The results suggest MGS Vereda cultivar’s potential for the renewal of coffee cultivations occurs in a rainfed system according to the environmental conditions of the experiment.Item Desempenho agronômico de cultivares de Coffea arabica L. após o “Esqueletamento/Safra Zero”(Universidade Federal de Lavras, 2020-02-13) Domingues, Cleiton Gonçalves; Botelho, Cesar Elias; Carvalho, Gladyston RodriguesA utilização de cultivares resistentes a doenças tem sido importante no controle das mesmas, pois os danos causados pelas doenças podem trazer perdas significativas à cultura, reduzindo a produtividade, devido ao depauperamento acentuado nas plantas. No manejo da lavoura cafeeira, tem-se utilizado a poda do tipo esqueletamento para renovação de lavouras, com a eliminação de partes improdutivas das plantas, favorecendo altas produtividades. A adoção do sistema “Safra Zero” passou a ser adotado a fim de manter o porte da lavoura e eliminar as colheitas em ano de safra baixa, preconizando ciclos de poda após anos de safra alta. Com isso, objetivou-se neste trabalho, identificar cultivares de café arábica mais produtivas e responsivas à poda tipo esqueletamento. Foi instalado um experimento na área experimental do Departamento de Agricultura, Setor de Cafeicultura da Universidade Federal de Lavras (UFLA), no mês de dezembro de 2005. O delineamento experimental utilizado foi de blocos ao acaso, com 25 cultivares de Coffea arabica L., 23 com graus de resistência à ferrugem e duas testemunhas comerciais suscetíveis (Topázio MG 1190 e Catuaí Vermelho IAC 144) com três repetições, no espaçamento de 3,5 x 0,7m e parcelas de 12 plantas. Em 2014, realizou-se o primeiro ciclo da poda do tipo esqueletamento, e o segundo ciclo foi realizado em agosto de 2016. Em 2018 foram avaliadas a produtividade, porcentagem de frutos chochos, porcentagem de frutos maduros, verdes e secos, vigor vegetativo, incidência de ferrugem e cercosporiose. Os dados obtidos foram analisados por meio do programa Genes, realizando a análise de variância à 5% de significância pelo teste F, e para o agrupamento das médias foi utilizado o teste de Scott-Knott. A cultivar Catucaí Amarelo 20/15 cv 479 é indicada para o sistema convencional e para o sistema “Safra Zero” por apresentar alta produtividade, e boa maturação dos frutos, contudo, é necessário o controle de doenças. As cultivares Palma II, Pau Brasil MG 1 e IPR 103 são altamente produtivas e apresentam recuperação após a poda do tipo esqueletamento. Destaque para a Palma II, que apresentou resistência à ferrugem e intermediário para cercosporiose, sendo a mais indicada para plantios em regiões de montanha.Item Defense responses to Meloidogyne exigua in resistant coffee cultivar and non-host plant(Sociedade Brasileira de Fitopatologia, 2013) Silva, Rodrigo V.; Oliveira, Rosângela D.L.; Ferreira, Patrícia S.; Ferreira, Aline O.; Rodrigues, Fabrício A.The resistance of coffee plants to Meloidogyne exigua is conferred by the gene Mex-1. However, the mechanisms of resistance still need to be clarified. Therefore, the penetration, development and reproduction of two populations of M. exigua (M1, isolated from the coffee plant and M2, from rubber tree) in susceptible (Coffea arabica ‘Catuai’) and resistant (C. canephora ‘Apoatã’) cultivars were studied. A greater quantity of J2 from M1 penetrated the susceptible cultivar, but there was no difference between the cultivars for M2. Although the resistant coffee cultivar formed some galls, the nematode did not reproduce. M2 did not induce the formation of galls or the production of eggs in either cultivars. Events related to hypersensitive reaction (HR) were observed as well as other defense responses of the coffee cultivar against M. exigua, which inhibited the formation of the feeding site, provoked emigration of the J2 and delayed or inhibited development and reproduction. The response of the non-host plant was more effective, because it did not allow development of the nematode or, consequently, its reproduction. It was concluded that the coffee cultivar’s resistance to M. exigua is not restricted to HR, but rather to a set of defense responses, both constitutive and induced, expressed after nematode penetration, especially phenolic-like compounds.Item Additional physiological races of coffee leaf rust (Hemileia vastatrix) identified in Kenya(Sociedade Brasileira de Fitopatologia, 2012) Gichuru, Elijah K.; Ithiru, John M.; Silva, Maria C.; Pereira, Ana P.; Varzea, Vitor M.P.Coffee leaf rust (CLR), caused by the fungus Hemileia vastatrix, is among the most important diseases affecting coffee all over the world. In Kenya, it is currently the second most important disease, and breeding coffee to obtain new resistant cultivars has been a priority. Over time, new rust pathogenic races able to infect hitherto resistant coffee genotypes have been registered. To date, 49 races of the pathogen have been characterized all over the world. The most recent races to be characterized are able to infect derivatives of Timor Hybrid (HDT), which is a major source of resistance in breeding programs. This work aimed to identify new races of the pathogen in Kenya, emphasizing infected leaves sampled from CLR resistant varieties and breeding lines collected from two sites (Ruiru and Koru). Twenty-four samples were characterized, out of which 22 samples corresponded to new races of the pathogen. A total of six new races (III, XVII, XXIII, XXXVI, XLI and XLII) were characterized, revealing three new virulence genes (v1, v7, v8) and possibly a fourth virulence gene, the v9. This finding represents a serious threat to coffee production and also a challenge to coffee breeding programs that are in progress in Kenya.