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.

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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 .

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.

The mini-grafting is a nondestructive vegetative propagation method based on grafting apical segments onto adult donor plantsderived rootstocks. Here, we aimed at evaluating the mini-grafting of shoot tips derived from adult Passiflora edulis f. flavicarpa plants (yellow passion fruit) onto vegetatively propagated rootstocks of P. mucronata (sandbank passion fruit). Different shoot tip lengths and the fastening material were assayed. A randomized block experimental design was set up following a 2 × 3 factorial scheme [shoots: 8-12 and 3-7 cm × fastening materials (circular clip, "V" shaped clip, and Parafilm ® )] totaling six treatments with four repetitions of eight plants each. The following characteristics were evaluated: graft setting (%); graft and rootstock diameters (mm); graft diameter/rootstock diameter ratio; cellular division in the graft region and starch presence in the graft and rootstock. Parafilm ® provided better adhesion (89.57%) compared to circular (76.03%) and "V" shaped clips (68.74%). The attachment was favored by rootstocks with 8-12 cm shoots (90.27%), compared with those of the 3-7 cm (65.96%). The presence of starch grains in the parenchymatic cells of the graft suggests the translocation of photo-assimilates from physiologically active mature leaves of P. edulis f. flavicarpa to the stem apex. Additionally, the hydrolysis and mobilization of the starch associated and the endogenous auxin levels in this meristematic region may have been responsible for improving the success of the mini-grafting.