Navegando por Autor "Rodrigues, Lucas Mateus Rivero"

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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, Oliveiro
Although 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.
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, Oliveiro
Bacterial 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.
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, Oliveiro
Pseudomonas 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.
Diferenciação de bactérias do gênero Pseudomonas patogênicas ao cafeeiro por técnicas serológicas
(Instituto Biológico, 2017) Beriam, Luis Otavio Saggion; Patrício, Flavia Rodrigues Alves; Maciel, Karen Wolf; Rodrigues, Lucas Mateus Rivero; Almeida, Irene Maria Gatti de
Há várias bactérias que causam problemas para o cafeeiro, incluindo Pseudomonas cichorii, P. syringae pv. garcae, P. syringae pv. tabaci, Burkholderia andropogonis e Xylella fastidiosa, todas elas já descritas no Brasil. Tentativas de diferenciar essas bactérias por testes serológicos de dupla difusão em ágar (dda), com antissoros produzidos contra células íntegras de P. s. pv. garcae, mostraram reações cruzadas, principalmente entre P. s. pv. garcae e P. s. pv. tabaci. Dessa forma, foram produzidos antissoros contra P. s. pv. garcae (linhagem patotipo IBSBF-248 — Coleção de Culturas de Fitobactérias do Instituto Biológico — IBSBF), obtidos por meio de imunizações de coelhos com antígenos de proteínas do complexo proteico da membrana (CPM). Esses antissoros foram testados por dupla difu são em agarose (dda) contra diversas formas de antígenos extraídos de P. cichorii, P. s. pv. garcae e P. s. pv. tabaci [células autoclavadas, células tratadas com formol, exopolissacarídeos (EPS), glicoproteí nas (GP) da cápsula bacteriana, proteínas de membrana e suspen são bacteriana (SB) em NaCl 0,85%]. Os resultados mostraram que, dependendo do antígeno e do meio suporte da dupla difusão (com ou sem MgCl2 e/ou azul de tripano), os antissoros reagem somente com P. s. pv. garcae. Desse modo, esses antígenos podem ser usados para a rápida diagnose da mancha aureolada do cafeeiro nos testes de dda.
Ethiopian coffee germplasm is a valuable resistance gene pool to brazilian Pseudomonas syringae PVS garcae and tabaci
(Editora UFLA, 2021) Rodrigues, Lucas Mateus Rivero; Destéfano, Suzete Aparecida Lanza; Beriam, Luís Otávio Saggion; Ferreiro-Tonin, Mariana; Braghini, Masako Toma; Guerreiro Filho, Oliveiro
Seven wild accessions of Coffea arabica from Ethiopia prospected by FAO Coffee Mission 1964-1965 were investigated concerning the resistance to 18 Brazilian strains and two Kenyan strains of Pseudomonas syringae pv. garcae and four P. syringae pv. tabaci strains, causal agents of bacterial halo blight and bacterial leaf spot, respectively. The cultivars of C. arabica IPR 102, resistant to the diseases, and Mundo Novo IAC 376-4, susceptible, were used as experimental controls. Our results indicated that the Ethiopian accessions presented high levels of resistance to all Brazilian strains of P. syringae pv. garcae but were susceptible to infection caused by Kenyan strains, which causes different levels of severity in wild accessions and experimental controls. Ethiopian accessions were also considered resistant to the four P. syringae pv. tabaci strains, with low susceptibility observed, one point on the severity scale, in access E-268 in response to a strain of the bacterium.
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 de
The 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.
Multiple resistance to bacterial halo blight and bacterial leaf spot in Coffea spp.
(Instituto Biológico, 2019) Rodrigues, Lucas Mateus Rivero; Destéfano, Suzete Aparecida Lanza; Almeida, Irene Maria Gatti de; Beriam, Luís Otávio Saggion; Braghini, Masako Toma; Guerreiro Filho, Oliveiro
Breeding for genetic resistance is an important method of crop disease management, due to the numerous benefits and low cost of establishment. In this study, progenies of 11 Coffea species and 16 wild C. arabica accessions were tested for their response to Pseudomonas syringae pv. garcae, the causal agent of bacterial halo blight, a widespread disease in the main coffee-producing regions of Brazil and considered a limiting factor for cultivation in pathogen-favorable areas; and also to P. syringae pv. tabaci, causal agent of bacterial leaf spot, a highly aggressive disease recently detected in Brazil. Separate experiments for each disease were carried out in a greenhouse, with artificial pathogen inoculations and ideal moisture conditions for disease development. The results showed that C. canephora, C. congensis, C. eugenioides, C. stenophylla, and C. salvatrix progenies, the wild C. arabica accessions Dilla & Alghe and Palido Viridis, and cultivar IPR 102 contain satisfactory levels of simultaneous resistance against bacterial halo blight and bacterial leaf spot. These results are useful in breeding programs for durable resistance to multiple biotic agents, providing new combinations of resistance alleles by hybridization, as well as for phytopathological studies, to identify infraspecific variability of the pathogens.
Restrição hídrica em plantas do genótipo BA-10 de Coffea arabica L.
(Embrapa Café, 2015) Carmazini, Valéria Cristina Barbosa; Alves, Ivanilda dos Santos; Rodrigues, Lucas Mateus Rivero; Almeida, Julieta Andrea Silva de
O objetivo deste estudo foi caracterizar respostas fisiológicas e morfológicas de plantas do genótipo BA-10 de Coffea arabica submetidas à restrição hídrica. Para tanto, utilizaram-se mudas mantidas individualmente em vasos de plástico, contendo 3 Kg de substrato, em casa de vegetação. O substrato consistiu da mistura de solo, areia e fibra de coco (3:1:1). Quando as plantas estavam em média com dez pares de folhas foram submetidas aos tratamentos de restrição hídrica e hidratação contínua, sendo aplicados em quatro ciclos, com intervalo de tempo entre cada um. Os tratamentos foram avaliados quanto à altura de planta, número de par de folhas, temperatura foliar, sintoma de murcha foliar, determinação das massas fresca e seca da parte aérea e do sistema radicular. Além disto, analisou-se o conteúdo relativo de água (CRA) e o teor de umidade do solo. Dos resultados obtidos, verificou-se que em geral as plantas de BA-10 submetidas à restrição hídrica apresentaram redução de altura da parte aérea e do número de par de folhas em relação ao controle, ao longo dos quatro ciclos aplicados. O CRA variou entre os tratamentos, sendo que as maiores taxas foram verificadas nas plantas submetidas à restrição hídrica no primeiro e terceiro ciclos enquanto as menores taxas ocorreram no segundo e quarto ciclos de restrição hídrica. Por outro lado, observou-se que os sintomas de murcha foliar iniciaram mais cedo nas plantas submetidas aos dois primeiros ciclos de restrição hídrica e mais tardiamente nos dois últimos. Os resultados obtidos indicam que as alterações bioquímicas e fisiológicas nas plantas submetidas à falta de água parecem induzir nestas algum grau de tolerância à seca
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, Oliveiro
Coffee 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.