Knowledge of the genetic variability of a population is essential to guide its preservation and maintenance in addition to increasing the efficiency of genetic breeding programs. On this basis, this study was conducted to evaluate the genetic diversity of Coffea canephora genotypes using multivariate statistical procedures applied to a set of morpho-agronomic variables. The materials employed in this study constitute a crop located in Vila Valério - ES, Brazil, where the genotypes are arranged in a randomized-blocks experimental design with four replicates. Significant differences were detected by the F test at the 1% or 5% probability levels among the genotypes for all evaluated traits, demonstrating heterogeneity of genetic constitution in the studied population, which is favorable to breeding, as it indicates the possibility to identify superior and divergent individuals. Based on the generalized Mahalanobis distance, the most divergent combinations were obtained between genotypes 23 and 10 (256.43) and 23 and 17 (250.09). The clusters formed by Tocher's optimization and the UPGMA hierarchical method agreed, both similarly grouping the genotypes into three clusters. Of the analyzed traits, mature fruit weight (19.08%), yield (15.50%), plant diameter (12.42%), and orthotropic-shoot internode length (10.94%) were the most efficient to explain the dissimilarity among the genotypes.

Tributun is a cultivar of Coffea canephora derived from breeding clones discovered by farmers. It was evaluated at 150 m asl in northern EspíritoSanto for yield, plant vigor and pest and disease resistance. The cultivar with six genotypes produces a mean yield of 90.87 bags ha -1 year -1 .

RESUMO-A importância econômica do mogno ressalta a relevância da análise do vigor de suas sementes visando à formação de mudas com qualidade. O objetivo foi avaliar a influência de diferentes temperaturas e períodos de exposição do teste de envelhecimento acelerado em sementes de mogno. As variáveis analisadas foram: teor de água, emergência de plântulas, índice de velocidade de emergência, freqüência relativa e tempo médio de emergência após o envelhecimento acelerado [(39; 41; 43 e 45 C, durante zero (testemunha), 24; 48; 72 e 96 horas]. O vigor de sementes de mogno pode ser avaliado por meio do teste de envelhecimento acelerado nas temperaturas de 39 o C/96 horas e 43 o C por 48 ou 96 horas. A combinação 43 o C/48 horas permite reduzir o tempo de execução das avaliações de sementes de mogno. O índice de velocidade de emergência é uma variável adequada para avaliar a influência do envelhecimento acelerado sobre sementes de mogno.

Coffee growers are searching for more sustainable production systems. Shaded cultivation is presented as a management option to attenuate coffee environmental stresses. This work aims at to evaluate the microclimate and coffee plant (Coffea canephora cv. Conilon Clone 02) development under different shading levels promoted by the intercropping with Australian cedar (Toona ciliata M. Roem. var. Australis) or under unshaded conditions. Australian cedar and Conilon coffee were planted in 15 × 2m and 3 x 1.2 m spacing, respectively, resulting in five rows of coffee to one row of Australian cedar. The closer the coffee rows were in relation to the Australian cedar trees the higher shade level was obtained. Climatic variables (temperature, irradiance and relative humidity) and leaf areas were evaluated over four seasons, and the internode lengths of plagiotropic and orthotropic branches were evaluated monthly. The 2013yield was also measured. There was a decrease in both the irradiance and temperature and an increase in the relative humidity at all times under shaded cultivation (closer to the Australian cedar row). The highest growth of plagiotropic and orthotropic branches and leaf expansion were found under shaded cultivation; however, the number of nodes per branch and the yields were similar among treatments. Growing Conilon coffee intercropped with Australian cedar showed a good yield potential.

No abstract