Abstract The aim of this work was to validate markers linked to the SH3 gene of coffee leaf rust (CLR) resistance and use them in assisted selection. Initially, we validated the markers in genotypes already known to carry SH3. Next, we performed phenotype and genotype evaluation for resistance to CLR in coffee plants growing under field conditions. We used Arabica coffee progenies derived from BA-10, which carries the SH3 gene due to introgression of C. liberica. Three SCAR markers (SP-M16-SH3, BA-48-21O-f, and BA-124-12K-f) and one SSR marker (Sat244) linked to SH3 gene were used to amplify the coffee plants’ DNA. Our assessments of markers validation in resistant genotypes, SP-M16-SH3 and BA-124-12K-f, were efficient to identify the SH3 gene. These two markers were used to evaluate the progenies derived from BA-10 and were significantly linked to the phenotype evaluations. The SP-M16-SH3 marker was more efficient, with the advantage of being codominant.

Abstract Cultivar IPR 106 resulted from a spontaneous hybridization between “Icatu IAC 925” and an unknow dwarf plant. It is a dwarf cultivar with high rusticity, late ripening cycle, large grains, excellent cup quality and resistance to some populations of the nematodes Meloidogyne paranaensis and M. incognita found in the state of Paraná.

ABSTRACT: Meloidogyne species are widely distributed in coffee growing areas in Brazil, where M. paranaensis is responsible to significant losses to the crop. One of the main management strategies is the use of resistant cultivars, such as Apoatã rootstock and cultivars IPR 100 and IPR 106. However, the parasitic relationship between coffee and M. paranaensis in cultivars carrying resistance genes has been poorly understood. The objective of this paper was to characterize the resistance response of Coffea arabica cv. IPR 106 to M. paranaensis. For this, penetration and histopathological studies were carried out using root tissues parasitized by the nematode. ‘IPR 106’ and ‘Mundo Novo’ (susceptible cultivar) seedlings were inoculated with 4,000 eggs of M. paranaensis and, 15 days after inoculation (DAI), roots were stained with fuchsine to verify the penetration rates of the nematode. Histopathological studies were conducted at 15, 30, 45 and 60 DAI and nematode reproduction was calculated at 120 DAI. ‘IPR 106’ did not avoid completely nematode penetration at 15 DAI, although the number of nematodes was 50 % lower than in Mundo Novo, disregarding the hypothesis of a pre-infectional mechanism of resistance that could prevent nematode penetration completely. However, giant cells and collapsed nematodes were observed in ‘IPR 106’ at 30 DAI, suggesting that the resistance mechanism to M. paranaensis in ‘IPR 106’ involves a post-infectional response and could be mediated by a hypersensitive reaction.

Abstract The aim of this study was to identify resistance to bacterial halo blight in Arabica coffee lines carrying Coffea racemosa genes. Eighteen Arabica coffee lines derivative from the genotype C1195-5-6-2, and the cultivars IAPAR 59 and IPR 99 were evaluated for resistance to bacterial halo blight in two trials carried out in field conditions, in Londrina, PR, Brazil. The cultivars Mundo Novo IAC 376-4 and Catuaí Vermelho IAC 81 were included as susceptible controls. Ten lines and the cultivar IAPAR 59 showed resistance to bacterial halo blight. The cultivar IPR 99 presented intermediate reaction, and the controls were very susceptible. This is the first study to show that lines derivative from the genotype C1195-5-6-2, which has C. racemosa genes, could be a source of resistance to bacterial halo blight in coffee breeding programs.

Abstract ‘IPR 100’ was derived from a crossing between “Catuaí” and a hybrid (“Catuaí” x BA-10 coffee). ‘IPR 100’ is a medium size dwarf cultivar with high rusticity, with late ripening cycle, and with resistance to Meloidogyne paranaensis and to some M. incognita populations.

RESUMO O objetivo do trabalho foi avaliar a reação ao nematoide Meloidogyne paranaensis em progênies de café arábica derivadas do Icatu. O experimento foi conduzido em telado, no Instituto Agronômico do Paraná (IAPAR), em Londrina, Paraná, Brasil. Mudas com três a quatro pares de folhas foram inoculadas com 5.000 ovos e juvenis de segundo estádio (J2) de Meloidogyne paranaensis. Foram avaliadas quatro progênies F4 de HN 87609 derivadas de ‘Icatu H4782-7-925’. Como padrões de suscetibilidade e resistência, foram utilizados, respectivamente, Coffea arabica cv. Catuaí Vermelho IAC 81 e C. arabica cv. IPR 100. O experimento foi instalado em blocos casualizados com 14 repetições e uma planta por parcela. As avaliações foram efetuadas 120 dias após a inoculação. Foram avaliados o número de ovos e J2 por gramas de raiz (Nematoides∙g–1) e o fator de reprodução (FR). Para classificar os níveis de resistência das progênies, foi utilizado o índice de suscetibilidade do hospedeiro (ISH). De acordo com Nematoides∙g–1, as progênies IAPAR 12232 e IAPAR 12231 não diferiram estatisticamente do padrão resistente ‘IPR 100’. Todas as progênies F4 de HN 87609 foram altamente resistentes pelo ISH e apresentaram 100% das plantas classificadas como altamente resistentes ou resistentes. Portanto, a resistência a M. paranaensis está condição homozigótica.

ABSTRACT The aim of this study was to evaluate the reaction of Arabica coffee progenies derived from Icatu to Meloidogyne paranaensis. The experiment was conducted under screenhouse conditions at Instituto Agronômico do Paraná (IAPAR) in Londrina, Paraná State, Brazil. Seedlings with three to four pairs of leaves were inoculated with 5,000 M. paranaensis eggs and second-stage juveniles (J2). Four F4 progenies of HN 87609 derived from Icatu H4782-7-925 were evaluated. C. arabica cv. Catuaí Vermelho IAC 81 and C. arabica cv. IPR 100 were susceptible and resistant checks, respectively. The experiment was conducted in a randomized blocks design with 14 replications of one plant per plot. Assessments were performed 120 days after inoculation. The number of eggs and second-stage juveniles (J2) per gram of roots (Nematodes∙g–1) and reproduction factor (RF) were evaluated. Host susceptibility index (HSI) was used to classify the resistance levels of coffees. In relation to Nematodes∙g–1, IAPAR 12232 and IAPAR 12231 progenies were not significantly different from the resistant check IPR 100. All F4 progenies of HN 87609 were classified as highly resistant by HSI and presented 100% of plants classified as highly resistant or resistant. Therefore, these progenies are homozygously resistant to Meloidogyne paranaensis.

O objetivo desse estudo foi selecionar progênies de café produtivas e com resistência à ferrugem em dois locais do Estado do Paraná (Brasil). Os experimentos de campo foram instalados no delineamento experimental em blocos ao acaso nos município de Itaguajé e Congonhinhas. Foram avaliadas as características produção, vigor vegetativo e resistência à ferrugem em nove progênies de café arábica e em três cultivares padrões. Vários genótipos derivados do "Sarchimor" e do "Catucaí" apresentaram plantas suscetíveis. Três cafeeiros do germoplasma Sarchimor e uma progênie "F6 de Catuaí x (Catuaí x cafeeiro da série BA-10)" foram selecionados para avanço de geração e têm potencial para se tornarem novas cultivares, pois apresentaram produção maior que 'IAPAR 59' e 'Tupi IAC 1669-33' e muitas plantas apresentaram resistência completa à ferrugem.

The aim of this study was to select high-yielding coffee progenies with resistance to coffee leaf rust for the State of Paraná (Brazil). Field experiments in a randomized block design were carried out in Itaguajé and Congonhinhas. Yield, vegetative vigor and rust resistance of nine progenies of Arabic coffee and three check cultivars were evaluated. Many genotypes derived from "Sarchimor" and "Catucaí" were susceptible. Three coffee genotypes of Sarchimor germplasm and the F6 generation of genotype "Catuaí x (Catuaí x BA-10 coffee)" were selected to advance generations and are promising to become new cultivars for being higher-yielding than 'IAPAR 59' and 'Tupi IAC 1669-33' and having a large number of plants with complete rust resistance.

The objective of the study was to evaluate the resistance to rust in coffee cultivars developed by research institutes of Brazil in Paraná state. Resistance to the local leaf rust races was assessed in high disease intensity field conditions at Londrina and Congonhinhas in 2009 and 2010.The cultivars were developed by the EPAMIG/UFV, IAPAR, IAC and MAPA/Procafé. The resistant standard 'IAPAR 59' and the susceptible standards Catuaí Vermelho IAC 144' and 'Bourbon Amarelo' were used. A randomized block design with three replications and plots with 10 plants was used. A scale from 1 to 5 based on the rust intensity was used to evaluate the resistance. The Catiguá MG 1, Catiguá MG 2, IAPAR 59, IPR 98, IPR 104, Palma II, Paraíso H-419-10-6-2-5-1, Paraíso H-419-10-6-2-10-1, Paraíso H-419-10-6-2-12-1, Pau Brasil MG 1 and Sacramento MG 1 cultivars presented complete resistance to rust at Londrina and Congonhinhas. The cultivars derived from the Catucaí germplasm were susceptible or showed different levels of partial resistance. Partial resistance to the rust was observed in several coffees derived from "Hibrido de Timor". 'Acauã' and 'Obatã IAC 1669-20' presented complete resistance at Londrina, but at Congonhinhas, they were partially resistant, indicating that different rust races have occurred at these two locations.

As cultivares de café IPR 99 ("Sarchimor") e IPR 107 ('IAPAR 59' x 'Mundo Novo IAC 376-4') eram no passado resistentes à ferrugem (Hemileia vastatrix). Os objetivos deste estudo foram: a) Identificar progênies dessas duas cultivares com resistência à ferrugem; b) Identificar progênies com resistência incompleta; c) Verificar a eficiência dos cruzamentos testes na seleção dessas cultivares. A avaliação da resistência em campo foi realizada em cafeeiros adultos expostos à população local de raças presentes no IAPAR. Foram avaliados 23 cruzamentos testes com progênies F3 de 'IPR 107' e 5 com progênies F4 de 'IPR 99'. Além disso, foram avaliadas 11 progênies F4 de 'IPR 107' e 5 progênies F5 de 'IPR 99', provenientes de autofecundação. Várias progênies das cultivares IPR 99 e 107 apresentaram alta freqüência de plantas com resistência completa e são portadoras de mais genes de resistência não quebrados pelas raças de ferrugem. Progênies das cultivares IPR 99 e IPR 107 com a resistência quebrada apresentaram resistência incompleta à população local de raças. Cruzamentos testes foram eficientes na seleção de progênies de café com mais genes de resistência não quebrados.

All plants of the coffee cultivars IPR 99 ("Sarchimor") and IPR 107 ('IAPAR 59' x 'Mundo Novo IAC 376-4') were resistant to rust (Hemileia vastatrix) in the past. Currently, susceptible plants were observed in the two cultivars due to the breakdown of resistance by new rust races. The aims of this study were: a) to identify coffee (Coffea arabica L.) progenies of the two cultivars with resistance to rust; b) to identify progenies with incomplete resistance; c) to investigate the efficiency of test-crosses for selection from these cultivars. Evaluation for field resistance was carried out in adult plants subjected to natural infection by the local leaf rust population at IAPAR. Twenty-three test-crosses with F3 progenies of 'IPR 107' and five with F4 progenies of 'IPR 99' were evaluated. Moreover, 11 F4 progenies of 'IPR 107' and five F5 progenies of 'IPR 99' derived from self pollinations were evaluated. Several progenies of the IPR 99 and 107 cultivars presented high frequency of resistant plants and thus should carry additional S H genes not defeated by specific rust races found at IAPAR. However, susceptible progenies of 'IPR 99' and 'IPR 107' presented incomplete resistance to the local race population. Test-crosses were efficient for selecting coffee progenies more resistant to rust.