Performance of intraspecific hybrids (Kouillou x Robusta) of Coffea canephora Pierre

摘要

The experiment was carried out in 2005 in the municipality of Ouro Preto do Oeste at the experimental station of Embrapa Rond?nia. 256 genotypes were evaluated, from nine hybridizations among parents of Kouillou (Cpafro 121, Cpafro 194, Cpafro 199 and Emcapa 03) and Robusta (Robusta 1675, Robusta 2258 and Robusta 640). The experimental design was a randomized complete block design, where each cross was represented by a maximum of 32 plants, distributed in four replications. The spacing used was 3.5 x 1.5 m. The average of six harvests and the yield of hulled coffee was 74.90 bags ha-1. Highlight for progeny is Emcapa 03 x Cpafro 194 with average yield of 97.71 bags ha-1. The estimated heritability observed for yield of coffee benefited, was 78.96%. The evaluation of six production seasons was allowed to verify the reliability of the genetic parameters in each set of crops. It was possible to observe that only the evaluation of the 1st and 2nd crops would be enough to estimate the genetic parameters with efficiency, with a coefficient of determination (R2) of 79.10%. With the inclusion of the 3rd crop, R2 estimates rose to 81.10%. The individual evaluations (per plant) carried out in 2006/2007, 2007/2008 and 2008/2009 crops showed the superiority of the plants from crosses 7, 8 and 9. In relation to resistance of orange rust, most of the genotypes were resistant to disease, and 75% of the genotypes did not present any type of infection symptoms. Among the susceptible genotypes, there was a variation between 1 and 15% in the degree of lesion intensity.