Periódicos

URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352

Navegar

Resultados da Pesquisa

Agora exibindo 1 - 6 de 6
  • Imagem de Miniatura
    Item
    Reaction of coffee genotypes to different populations of Meloidogyne spp.: detection of a naturally virulent M. exigua population
    (Sociedade Brasileira de Fitopatologia, 2009) Muniz, Maria de Fátima S.; Campos, Vicente P.; Moita, Antônio W.; Gonçalves, Wallace; Almeida, Maria Ritta A.; Sousa, Fábio Rodrigues de; Carneiro, Regina Maria D. G.
    The reaction of seven genotypes of Coffea arabica to 10 Meloidogyne spp. populations collected mainly from coffee plantations in Brazil and Costa Rica was evaluated under greenhouse conditions. The inoculum consisted of 10,000 eggs per plant. Evaluations were done 8 months after inoculations considering the root fresh weight, gall and egg mass indices, number of eggs per gram of root and reproduction factor (RF). The cultivars Obatã IAC 1669-20, Sarchimor IAC 4361 and Tupi Amarelo IAC 5111 exhibited susceptibility to the four Brazilian M. exigua populations tested. However, cv. Tupi Vermelho IAC 1669-33 revealed resistance (RF value of 0.7) to the M. exigua population from Lavras, Minas Gerais State, Brazil. A population of M. exigua from Bom Jesus de Itabapoana, Rio de Janeiro State, Brazil, was highly virulent on cv. IAPAR 59 (RF= 165.7), bearing resistance gene Mex-1, and was also virulent on genotype Paraíso (H 419-5-4-5-2) (RF=396.2). A Meloidogyne sp. population on coffee from Garça, São Paulo State, Brazil, reproduced at low rates (RF ranging from 0.1 to 3.9) on all genotypes. All tested cultivars were susceptible to M. incognita and M. paranaensis. M. mayaguensis of guava from Paraná State, Brazil, reproduced at low rates in all coffee genotypes; however, another population of coffee, from Costa Rica, was more aggressive and showed RF value that ranged from 0.8 to 12.4. Results of this study point for the first time to the ability of a naturally occurring M. exigua population to overcome the resistance conferred by the Mex-1 gene.
  • Imagem de Miniatura
    Item
    IAC Catuaí SH3 - a dwarf Arabica coffee cultivar with leaf rust resistance and drought tolerance
    (Crop Breeding and Applied Biotechnology, 2019) Fazuoli, Luiz Carlos; Braghini, Masako Toma; Silvarolla, Maria Bernadete; Gonçalves, Wallace; Mistro, Júlio César; Gallo, Paulo Boller; Guerreiro Filho, Oliveiro
    The cultivar IAC Catuaí SH3 was developed by the pedigree method, from the recombination of the coffee tree H 2077-2-5-46, of the Catuaí Vermelho germplasm, with accession IAC 1110-8, from the exotic cultivar BA10. Cultivar IAC Catuaí SH3 is high-yielding, resistant to coffee leaf rust and tolerant to drought.
  • Imagem de Miniatura
    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, Oliveiro
    To 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.
  • Imagem de Miniatura
    Item
    IAC Obatã 4739 – dwarf arabic coffee cultivar with yellow fruits and resistant to leaf rust
    (Crop Breeding and Applied Biotechnology, 2018-07) Fazuoli, Luiz Carlos; Braghini, Masako Toma; Silvarolla, Maria Bernadete; Gonçalves, Wallace; Mistro, Júlio César; Gallo, Paulo Boller; Guerreiro Filho, Oliveiro
    Cultivar IAC Obatã 4739 was derived from a cross between coffee tree IAC 1669-20-1 and cultivar Catuaí Amarelo IAC 62. It is short and high-yielding, rust-resistant, has large and yellow fruits, medium to late maturation, excellent cup quality, and responds effectively to irrigation.
  • Imagem de Miniatura
    Item
    IAC 125 RN – A dwarf coffee cultivar resistant to leaf rust and root-knot nematode
    (Crop Breeding and Applied Biotechnology, 2018-03) Fazuoli, Luiz Carlos; Braghini, Masako Toma; Braghini, Masako Toma; Silvarolla, Maria Bernadete; Gonçalves, Wallace; Mistro, Júlio César; Gallo, Paulo Boller; Guerreiro Filho, Oliveiro
    IAC 125 RN was derived from a cross between the coffee cultivar Villa Sarchí and the Hibrido de Timor CIFC 832/2. The coffee trees are short and re- sistant to races 1 and 2 of the nematode Meloidogyne exigua and to all races of coffee rust, Hemileia vastatrix, present in Brazil. Brazil.
  • Imagem de Miniatura
    Item
    Flutuação populacional do bicho-mineiro em cultivares de café arábica resistentes à ferrugem
    (Instituto Agronômico (IAC), 2005-10) Conceição, Celso Henrique Costa; Guerreiro-Filho, Oliveiro; Gonçalves, Wallace
    A intensidade de infestação pelo bicho-mineiro, Leucoptera coffeella (Guérin-Méneville) (Lepidoptera: Lyonetiidae) foi investigada nas cultivares Obatã IAC 1669-20 e Tupi IAC 1669-33, com resistência à ferrugem das folhas do cafeeiro, Hemileia vastatrix Berk. et Br., e Ouro Verde Amarelo IAC 4397, suscetível à doença, em ensaios de campo, localizados em Campinas (SP), Brasil. A incidência de ferrugem e a ocorrência de inimigos naturais da praga, assim como o enfolhamento das plantas, foram também observados nas três cultivares. As curvas de flutuação populacional obtidas para Obatã IAC 1669-20 e Tupi IAC 1669-33 revelaram maior incidência do bicho-mineiro entre abril e novembro. Já na cultivar Ouro Verde Amarelo IAC 4397, observaram-se dois picos de infestação, sendo o primeiro em abril-maio e o segundo em agosto-setembro. No entanto, a elevada percentagem de folhas minadas nas cultivares Tupi IAC 1669-33 e Obatã IAC 1669-20 em relação à Ouro Verde Amarelo IAC 4397 não é evidência de maior suscetibilidade à praga, mas sim devido à maior retenção foliar dessas cultivares, em conseqüência da resistência à ferrugem das folhas observada em ambas. De maneira oposta, na cultivar Ouro Verde Amarelo IAC 4397, os sintomas de ataque do bicho-mineiro ocorreram em menor nível especialmente devido a maior queda de folhas. Com base nas diferenças observadas entre as cultivares, sugere-se a adoção de estratégias distintas de manejo da praga.