Coffee leaf rust (Hemileia vastatrix Berk.& Br.) is the main coffee disease in State of São Paulo, Brazil. Hybrids of selected resistant coffee plants and short sized commercial Coffea arabica cultivars, as Caturra Vermelho and Vila Sarchi, originally developed at the CIFC, Oeiras, Portugal, have been selected for rust resistance and high yield in many experimental coffee centers in Brazil. This paper reports a comparative study of the hybrids selected at the Instituto Agronômico, Campinas, São Paulo State, with the most promising progenies developed in the States of Minas Gerais, Espírito Santo and Paraná. An experimental trial, EP299, was established in Campinas in 1982 in a randomized block design with seven replications, with 30 progenies of the hybrid Caturra Vermelho x Híbrido de Timor (CV x HT), 12 of Vila Sarchi x Híbrido de Timor (VS x HT), and 15 of `Catuaí', in plots of two hills and a single plant per hill. Catuaí progeny, CH2077-2-5-81-2, without chemical treatment against rust disease, was used as control. Results of variance analysis indicated differences in the total yield (1984-1989) of the progenies. Among the three highest yielding progenies, two were from Catuaí and one from CV x HT. The results showed that the average of the Visual Evaluation Index was higher for the Catuaí progenies, however, plants with good vegetative aspect could also be found among the highest yielding progenies of CV x HT and VS x HT. The average value for fruit ripening indicated that the CV x HT and VS x HT progenies present early maturation than Catuaí. In relation to rust infection there were homozygous progenies for resistance in CV x HT and VS x HT. Catuaí progenies were rust susceptible. High positive correlation was observed among the variables studied. It was possible to classify the treatments in two groups according to a Principal Component Analysis (PCA). The first one is represented by the Catuaí Vermelho and Catuaí Amarelo, and the second, by plants derived from CV x HT and VS x HT. In the former group, plants were more productive, with higher Visual Evaluation Index (IAV), late fruit ripening, susceptible to the leaf rust disease agent, taller and with higher canopy diameter than in the second one. Highly promising high yield plants were observed in the C2591-5 population, derived from CV x HT, that exhibited also resistance to coffee rust disease.
Coffea arabica; Hemileia vastatrix; coffee; Coffea arabica; coffee leaf rust; Hemileia vastatrix; resistance; Híbrido de Timor
