Biblioteca do Café
URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/1
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Resultados da Pesquisa
Item Can the leaf age influence the susceptibility to bacterialleaf- spot and bacterial-halo-blight on coffee seedlings?(Instituto Biológico, 2018) Tomiyama, Ana Laura Midori Rossi; Rodrigues, Lucas Mateus Rivero; Andrade, Vinicius Teixeira; Beriam, Luis Otavio Saggion; Destéfano, Suzete Aparecida Lanza; Guerreiro Filho, OliveiroPseudomonas syringae van Hall, 1902, causes yield losses in innumerous economic important crops. On coffee trees, P. syringae pv. garcae causes the bacterial-halo-blight (BHB) and P. syringae pv. tabaci the bacterial-leaf-spot (BLS). Recently, these diseases incidence has increase in occurrence areas and aggressiveness in Brazil. Although leaf age plays a role in the severity response of BHB, it is not known yet if this phenomenon also occurs in coffee-BLS interaction, and with highly virulent strains. So, we examined differences in the diseases severity by inoculation of P. syringae pv. garcae and P. syringae pv. Tabaci strains on coffee leaves with different ages, to compare this aspect with coffee-BLS interaction. Our results showed that, for both pathovars, the severity was greater at the first internodes leaves, although for the most aggressive strains it was quite similar on any leaf age.Item Anatomical changes on coffee leaves infected by Pseudomonas syringae pv. garcae(Grupo Paulista de Fitopatologia, 2015) Rodrigues, Lucas Mateus Rivero; Queiroz-Voltan, Rachel Benetti; Guerreiro Filho, OliveiroAlthough poorly studied, the bacterial halo blight is an important disease in the major coffee-producing states of Brazil. External damage and anatomical changes on leaves were measured in seedlings of Coffea arabica cv. Mundo Novo, susceptible to Pseudomonas syringae pv. garcae, by using histological sections obtained at 10 and 20 days after inoculation (DAI). The changes on the epidermis were smaller than the lesions measured in the mesophyll, irrespective of the evaluated colonization period, showing that the internal damage caused by the bacterium represent twice the damage observed externally. From the inoculation site, lysis occurred on the epidermal cells and on the palisade and spongy parenchyma cells, with strong staining of their cellular contents, as well as abnormal intercellular spaces in the palisade parenchyma, hypertrophy and hyperplasia of mesophyll cells and partial destruction of chloroplasts. Additionally, this study revealed the presence of inclusion bodies in epidermal and mesophyll cells. Bacterial masses were found in the apoplast between and within mesophyll cells. Bacteria were also observed in the bundle sheath and vascular bundles and were more pronounced at 20 DAI, not only near the inoculation site but also in distant areas, suggesting displacement through the vascular system. These results can be useful to understand this plant-pathogen interaction.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 First report of mixed infection by Pseudomonas syringae pathovars garcae and tabaci on coffee plantations(Instituto Agronômico (IAC), 2017-10) Rodrigues, Lucas Mateus Rivero; Sera, Gustavo Hiroshi; Guerreiro Filho, Oliveiro; Beriam, Luis Otavio Saggion; Almeida, Irene Maria Gatti deThe bacterial-halo-blight (Pseudomonas syringae pv. garcae) is disseminated by the main coffee areas in the producing states of Brazil. On the other hand, the disease bacterial-leaf-spot (Pseudomonas syringae pv. tabaci) was reported only once in coffee seedlings in a sample collected in the State of São Paulo. In mid-2015, samples of coffee leaves with symptoms of foliar lesions surrounded by yellow halo, were collected in coffee plantations in the State of Paraná and fluorescent bacteria producing or not brown pigment in culture medium were isolated and determined as belonging to the Group I of P. syringae. Through biochemical, serological and pathogenicity tests, the pathogens were identified as P. syringae pv. garcae and P. syringae pv. tabaci, with prevalence of isolates belonging to pathovar tabaci and, as well as in certain samples, it was identified simultaneous infection by both etiological agents. Then, this is the first report of associated occurrence of garcae and tabaci pathovars of P. syringae and of the incidence of “bacterial-leaf-spot” under field conditions and in the State of Paraná.Item SH1 leaf rust and bacterial halo blight coffee resistances are genetically independent(Instituto Agronômico (IAC), 2017-04) Rodrigues, Lucas Mateus Rivero; Braghini, Masako Toma; Guerreiro Filho, OliveiroCoffee resistance to Pseudomonas syringae pv. garcae has been associated to pleiotropic effect of SH1 allele, present in coffee plants resistant to certain races of Hemileia vastatrix, the causal agent of leaf rust, or genetic linkage between resistance alleles to both pathogens. To validate this hypothesis, 63 coffee plants in F2 generation were evaluated for resistance to 2 isolates of H. vastatrix carriers of alleles, respectively, v2, v5 (isolate I/2015) and 1; v2; v5 (isolate II/2015) with the objective to confirm presence of SH1 allele in resistant plants to isolate I/2015. The same coffee plants were evaluated for resistance to a mixture of P. syringae pv. garcae strains highly pathogenic to coffee. Results showed that, among F2 coffee allele SH1 carriers, resistant to isolate I/2015, resistant and susceptible plants to bacterial halo blight were found; the same segregation occurs between F2 homozygous for SH1 allele, susceptible to the same isolate (I/2015) of H. vastatrix. Results also indicate that there is no pleiotropic effect of gene or allele SH1 connection between genes conferring resistance to leaf rust caused by H. vastatrix and bacterial halo blight caused by P. syringae pv. garcae.Item Bacterial halo blight of coffee crop: aggressiveness and genetic diversity of strains(Instituto Agronômico (IAC), 2018-01) Maciel, Karen Wolf; Destefano, Suzete Aparecida Lanza; Beriam, Luis Otavio Saggion; Almeida, Irene Maria Gatti de; Patricio, Flavia Rodrigues Alves; Rodrigues, Lucas Mateus Rivero; Guerreiro Filho, OliveiroBacterial halo blight, caused by Pseudomonas syringae pv. garcae, is an important disease of coffee crop occurring in Brazil and other countries. In recent years, outbreaks of this disease have damaged several coffee crops in Brazil. Aggressiveness and genetic diversity of 25 strains of P. s. pv. garcae, obtained between the years 1958 and 2011, in 23 cities of São Paulo and Minas Gerais states, as well as three strains from Kenya were evaluated in this study. The strains were inoculated on coffee seedlings cultivar Mundo Novo, and their genetic diversity was evaluated by ERIC-PCR, REP-PCR, and their combination. All the strains were pathogenic to the coffee seedlings; the results of pathogenicity tests, in both experiments, could be divided in four aggressiviness classes (highly aggressive; aggressive; moderately aggressive and less aggressive). The Kenyan strains grouped separately from the Brazilian strains with ERIC-PCR and the combination of ERIC- and REP-PCR. The Brazilian strains could be grouped in two sub-clusters, the first including the older strains, obtained from 1958 to 1978, and the other comprising the remaining strains. With a few exceptions, strains isolated from 1997 to 2011, grouped mainly by their region of origin, were predominantly isolated from higher altitude regions, above 800 m. This probably occurred because the climatic conditions that prevail in these regions, characterized by milder temperatures and regular rainfall, are favorable for the coffee crop and for the production of high quality coffee beverage, but can be also favorable to bacterial halo blight.Item Avaliações preliminares da resistência à cochonilha-da-raiz Dysmicoccus texensis em clones de Coffea canephora resistentes a Meloidogyne spp(Editora UFLA, 2012-05) Fatobene, Bárbhara Joana dos Reis; Guerreiro Filho, Oliveiro; Gonçalves, WallaceInvestigou-se, neste trabalho, a variabilidade de cafeeiros quanto à resistência apresentada à cochonilha-da-raiz, Dysmicoccus texensis e a nematoides do gênero Meloidogyne. Ambas as espécies configuram problemas fitossanitários importantes para a cafeicultura, sobretudo nas regiões da Alta Mogiana e Alta Paulista no Estado de São Paulo. A interação entre D. texensis e sete clones de C. canephora resistentes à diferentes espécies do gênero Meloidogyne foi avaliada em experimento realizado em casa de vegetação, observando-se as diferenças nos padrões de infestação apresentados pelos clones. A reprodução de cochonilhas no sistema radicular dos clones IAC 5, EH 5, EH 7, EH 101 e EH 199 foi bastante reduzida, sugerindo a possibilidade de reunir nos mesmos resistência múltipla aos dois agentes bióticos.Item Crescimento e severidade de cercosporiose em mudas de café cv. catuaí vermelho IAC 144, cultivadas em soluções completa e deficientes em N e K(Embrapa Café, 2015) Maciel, Karen Wolf; Moura, Karina Elaine de; Moura, Kamila Ellen de; Braghini, Masako Toma; Guerreiro Filho, Oliveiro; Patricio, Flávia Rodrigues AlvesA cercosporiose, causada por Cercospora coffeicola, é uma importante doença do cafeeiro que ocorre em todas as regiões produtoras do Brasil. A doença tem causado prejuízos nas lavouras com altas produtividades e que empregam elevada tecnologia. A cercosporiose causa lesões em folhas e frutos e é mais severa em plantas com deficiências na nutrição, especialmente na relação N e K. Este trabalho foi realizado com o objetivo de avaliar o efeito de deficiências de N e K sobre o crescimento e a severidade da cercosporiose em mudas de cafeeiro da cultivar Catuaí Vermelho IAC 144. Mudas de cafeeiro foram cultivadas em soluções hidropônicas completa e deficientes em N e/ou K por três meses. Após a indução das deficiências as mudas foram inoculadas com uma suspensão contendo 105 conídios de C. coffeicola, preparada com a mistura de cinco isolados do patógeno. Quarenta dias após a inoculação avaliou-se o crescimento das plantas e a severidade da cercosporiose. As mudas cultivadas nas soluções com N apresentaram maior comprimento, peso seco da parte aérea e número de folhas muito superior ao das cultivadas nas soluções sem N. As mudas deficientes em N exibiram maior comprimento do sistema radicular e maior severidade da cercosporiose, além de maior queda de folhas por causa dessa doença. Entretanto, as plantas com níveis adequados deste nutriente também foram atacadas pela cercosporiose. As plantas cultivadas nas soluções deficientes em K apresentaram menor teor deste nutriente nas folhas, porém não tiveram seu crescimento reduzido. Também não houve influência da falta de K na solução sobre a severidade da cercosporiose nas mudas de cafeeiro, provavelmente porque as suas folhas ainda mantinham níveis razoáveis de K até o final do experimento.Item IAC Tupi RN, uma cultivar de café com resistência múltipla à ferrugem e ao nematóide meloidogyne exigua(Embrapa Café, 2011) Fazuoli, Luiz Carlos; Braghini, Masako Toma; Silvarolla, Maria Bernadete; Gonçalves, Wallace; Mistro, Júlio César; Guerreiro Filho, Oliveiro; Gallo, Paulo Boller; Almeida, Saulo Roque deO objetivo do presente trabalho é apresentar a cultivar IAC Tupi RN, que apresenta resistência múltipla à ferrugem e ao nematóide Meoidogyne exigua.Item Características agronômicas de cafeeiros resistentes ao bicho-mineiro obtidos a partir de propagação vegetativa por estaquia(Embrapa Café, 2013) Mendonça, Alex Paulo; Guerreiro Filho, OliveiroA clonagem de cafeeiros a partir da propagação vegetativa de plantas resistentes heterozigotas é uma forma de abreviar o tempo de obtenção de novas cultivares resistente a pragas e doenças. Analisou-se o desempenho dos clones IAC 1059, IAC 1064, IAC 760 e IAC 1215 obtidos por estaquia de cafeeiros resistentes ao bicho mineiro, em Campinas SP. As plantas foram avaliadas individualmente em função da produção de frutos, resistência ao bichomineiro, Leucoptera coffeela e à ferrugem, Hemileia vastatriz, em ensaios de campo e em laboratório. O clone IAC 1059 multiplicado por estaquia foi 22% mais produtivo que os demais clones e as testemunhas propagadas por semente. O nível de resistência ao bicho-mineiro e à ferrugem apresentados pelas plantas matrizes se mantém nas progênies clonais.