A seca é um dos fatores limitantes ao desenvolvimento dos cafeeiros arábicos e fontes de tolerância existem nas diferentes espécies de Coffea spp. O objetivo neste trabalho foi avaliar a tolerância à seca em mudas de 21 genótipos de café, portadores de genes de diferentes espécies, por meio da avaliação do grau de murchamento de suas folhas quando submetidas a períodos de restrição hídrica. O delineamento experimental foi inteiramente ao acaso, com 24 repetições de uma muda de seis meses de idade por parcela. O experimento foi conduzido em casa de vegetação no Instituto Agronômico do Paraná (IAPAR) em Londrina, Paraná, Brasil. Foram efetuadas duas avaliações visuais, por um índice de murcha das folhas, com notas de 1 a 9, seis dias após o início da restrição hídrica. As avaliações visuais quanto à intensidade de murcha em mudas permitiram discriminar satisfatoriamente genótipos com maior tolerância à seca. O genótipo mais tolerante à seca foi IAPAR 11260, um Coffea arabica (portador de genes de Coffea racemosa), seguido de Coffea arabica da Etiópia E368, ‘IPR 100’ (portador de genes de Coffea liberica) e ‘IPR 103’ (portador de genes de Coffea canephora). O Coffea canephora cv. ‘Apoatã IAC 2258’ foi mais sensível à seca do que todos os genótipos de Coffea arabica.

The aims of this study were: (a) to evaluate the resistance of coffee cultivars to Pseudomonas syringae (PS); (b) verify if there are coffee genotypes that present less wounds on the leaves; (c) to study the correlation between amount of wounds and PS severity. The field trial was installed in April 2014 at the IAPAR’s experimental station (Londrina, Paraná, Brazil). 18 Arabica coffee cultivars were evaluated. The cultivars Mundo Novo IAC 376-4 and Catuaí Vermelho IAC 81 were the susceptible controls and IPR 102 was the resistant control. After 32 months of planting the field trial, resistance to PS was evaluated in December 2016. The evaluation of the PS severity was carried out under conditions of natural infections of P. syringae pv. garcae and P. syringae pv. tabaci based on the symptoms, using a grading scale from 1 to 5. The number of wounds on the leaves of the eight cultivars were counted. The results showed that IPR 102 was resistant to Pseudomonas syringae, whereas IPR 99, Arara, IPR 107, Acauã, Sabiá, Catucaiam 24137, Japy and Catuaí Vermelho IAC 81 were susceptible. Mundo Novo and Catucaí Amarelo 2SL were more susceptible than Catuaí Vermelho. IPR 106, Japiam, Catiguá MG 2, Catiguá MG 1 and IBC Palma 2 showed moderate resistance, while IPR 103 and Catucaiam 2015479 were moderately susceptible. The cultivars IPR 102 and IPR 106 presented resistance to wounding because they had lower wounds than other cultivars. Increased leaf wounds was associated with increased P. syringae severity.

No abstract

The aim of this work was to evaluate the reaction of IPR 100 derived Arabica coffee lines to the nematode Meloidogyne paranaensis and to investigate the association between the parameters used to select resistant genotypes. The experiment was carried out in a greenhouse at IAPAR in Londrina -PR, Brazil. The resistance to M. paranaensis of nineteen Coffea arabica F 3 lines derived from the cross "PRFB E9705-9" × 'IPR 100' and three from the cross 'IPR 100' × "Sarchimor E9601 III-19-1" were assessed. Plants with three to four pairs of leaves were inoculated with 5000 M. paranaensis eggs and J 2 juveniles. After 90 days of inoculation, the variables reproduction factor (RF), fresh weight of roots (FWR) and number of eggs and J 2 juveniles per gram of roots (Nematodes.g -1 ) were assessed. Reduction in the reproduction factor (RRF) and host susceptibility index (HSI) were used to classify the resistant levels. Resistant lines were identified and the use of RRF, HSI and RF indices together helped to identify genotypes with resistance to nematodes. In the present study, statistical difference between the FWR of the genotypes was observed. Thus, if the indices are used alone, it is likely that HSI is better, since it can minimize possible interference in the classifications due to differences between the root volumes of the assessed genotypes. The percentage of plants with different resistance levels based on the classification of RRF and HSI and percentage of resistant plants based on RF are useful to identify homozygous and heterozygous genotypes.

- 'IAPAR 59' and 'Tupi IAC 1669-33' and having a large number of plants with complete rust resistance.

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.

<p><strong> </strong>O objetivo desse estudo foi identificar cafeeiros com ciclo de maturação precoce e muito precoce com alta produtividade, em progênies de café arábica portadoras de genes de <em>C. racemosa</em>. O experimento de campo foi instalado no IAPAR, em setembro de 2007, em Londrina, PR, Brasil. O delineamento experimental foi em blocos ao acaso, com três repetições e parcelas de cinco plantas no espaçamento de 2,5 x 0,5 m. Foram avaliadas 17 progênies F1RC6 derivadas de retrocruzamentos de diferentes genótipos de café arábica com uma planta F2 do genótipo C1195-5-6-2. Como padrões comparativos foram utilizadas as cultivares IAPAR 59, IPR 99 e Catuaí Vermelho IAC 81 que possuem, respectivamente, ciclos de maturação semiprecoce, semitardio e tardio. Foram avaliadas as características produção, vigor vegetativo e ciclo de maturação dos frutos. As avaliações de maturação e vigor foram realizadas através de escala de notas e a produtividade em volume de frutos. As progênies H0509, H0501, H0518, H0513, H0508, H0510, H0505, H0506, H0514 e H0504 foram mais precoces do que seus parentais. Entre elas, as progênies H0518, H0507 e H0508 foram mais produtivos do que as testemunhas e não diferiram estatisticamente quanto ao vigor vegetativo. Foram identificadas 10 progênies F1RC6 de café arábica, portadoras de genes de <em>C. racemosa</em> com potencial para se tornarem cultivares com ciclo precoce e muito precoce. A característica de ciclo precoce de maturação dos frutos de <em>C. racemosa</em>, presente no C1195-5-6-2, permaneceu após os diversos ciclos de cruzamento com <em>C. arabica</em>.<strong></strong></p>

The aim of this study was to assess the resistance to red mite (Oligonychus ilicis) in Coffea arabica genotypes with introgression of genes from a different species (Coffea racemosa). The experiment was conducted in a greenhouse at IAPAR (Londrina, PR, Brazil), between January 2016 and January 2017. The experiment was conducted in a completely randomized design with five genotypes, 12 replications of one plant per plot. The C. arabica cultivars IPR 100, IPR 99 and IPR 103 were evaluated as well as an F4 Arabica coffee line IAPAR H0113-40-26-10 with introgressed C. racemosa genes. Catuaí Vermelho IAC 99 cultivar, which is a pure C. arabica, was used as a susceptible control. In conditions of high natural infestation of red mite, the resistance of coffee genotypes was evaluated using a standard visual evaluation in January 2017. This evaluation was based on the percentage of leaf area with typical symptoms caused by this mite. Only one genotype, the F4 line IAPAR H0113-40-26-10 showed resistance to the red mite because present less leaf area with symptoms compared to other genotypes. The Arabica coffee cultivars IPR 99, IPR 100 and IPR 103 are as susceptible to red mite as to the susceptible control Catuaí Vermelho IAC 99.