Cross-pollination and gametophytic selfincompatibility reduce the stability of Coffea canephora genotypes. This is an important crop for Brazil, the largest producer of this type of coffee and also a major exporter. The study of biometric characteristics is essential to assist in the selection of promising plant materials. We examined the diversity of morpho-agronomic traits of genotypes of C. canephora cv. Conilon through the evaluation of branch and leaf parameters. Assessments included plagiotropic ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 19 (2): gmr18541 D. Dubberstein et al. 2branch length, number of nodes in plagiotropic branches, distance between nodes in plagiotropic branches, orthotropic branch length, number of nodes in orthotropic branch, distance between nodes in orthotropic branch, plant height, canopy diameter, leaf length, leaf width, and leaf area in two periods. The data from the 43 coffee genotypes were tested by multivariate and cluster analyses. Six groups were formed by the Tocher optimization method, and five groups by the unweighted pair group method with arithmetic mean (UPGMA) hierarchical method, suggesting an important genetic variability among plant materials. Both Tocher optimization and UPGMA hierarchical methods were consistent for clustering the genotypes, ordering them in six and five dissimilar groups, respectively, with genotypes 25 and 37 standing out with the greatest dissimilarity, constituting isolated groups by both methods. Pearson's correlation ranged from very weak to very strong, positive and negative, among the characteristics, as also shown by principal component analyses. These analyses indicated the morpho-agronomic traits with a greater degree of correlation, assisting in the choice of promising plant materials. The genetic parameters estimates demonstrate genetic variability and thus breeding potential within the Conilon coffee genotypes studied. These results emphasize the usefulness of biometric evaluations as a tool for the identification and breeding of genotypes to compose new Conilon coffee cultivars.

Leaf morpho-anatomical characteristics directly reflect photosynthetic performance and the ability to adapt to different environmental conditions. The study of biometric traits is essential for the selection of promising plant materials for breeding purposes. To identify new varieties of coffee plants with desirable traits for genetic improvement programs, this study investigated the variability of leaf morpho-anatomical traits in 43 genotypes of Coffea canephora (as the species under study is hypostomatous). Seven leaf characteristics were used: epidermal cell density (ECD), stomatal length (SL), stomatal width (SW), stomatal density (SD), stomatal size (SS), stomatal index (SI), and stomatal length/width. Morphological traits (plant height, internodal distance, and leaf area) and grain production were also assessed. The data analyzed multivariate analysis of variance grouped by the unweighted pair group the arithmetic mean hierarchical method, and data were also subjected to a Pearson linear correlation and principal component analyses (PCAs). The results showed wide morphological variability reflecting six morphological groups, which is relevant for the genetic divergence analysis and for breeding purposes, as the results have the potential to identify superior genotypes. Within the groups, genotypes were mainly separated by the number of epidermal cells and the number and size of the stomata, reflecting a high genetic heterogeneity within genotypes. Positive and negative correlations were found, with levels of significance ranging from weak to strong among the analyzed traits. The highest correlation levels were found for SL × SS, SW × SS, and SI × SD. In addition, the PCA indicated that plant height, distance between nodes, and leaf area were positively correlated and associated. The greater the number and width of stomata, the higher the rate of gas exchange. Both characteristics are favorable for the development and production of coffee plants, explaining the positive correlation observed in this study. These results emphasize the usefulness of trait evaluations for the identification and breeding of genotypes to compose new C. canephora cultivars suitable for changing environments.

ABSTRACT. The family Myrtaceae is widespread in the AtlanticForest and is well-represented in the Espírito Santo State in Brazil. In the genus Psidium of this family, guava (Psidium guajava L.) is the most economically important species. Guava is widely cultivated in tropical and subtropical countries; however, the widespread cultivation of only a small number of guava tree cultivars may cause the genetic vulnerability of this crop, making the search for promising genotypes in natural populations important for breeding programs and conservation. In this study, the genetic diversity of 66 guava trees sampled in the southern region of Espírito Santo and in Caparaó, MG, Brazil were evaluated. A total of 28 morphological descriptors (11 quantitative and 17 multicategorical) and 18 microsatellite markers were used. Principal component, discriminant and cluster analyses, descriptive analyses, and genetic diversity analyses using simple sequence repeats were performed. Discrimination of accessions using molecular markers resulted in clustering of genotypes of the same origin, which A.M. Nogueira et al. 10658©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 13 (4): 10657-10668 (2014) was not observed using morphological data. Genetic diversity was detected between and within the localities evaluated, regardless of the methodology used. Genetic differentiation among the populations using morphological and molecular data indicated the importance of the study area for species conservation, genetic erosion estimation, and exploitation in breeding programs.

Knowledge of the leaf characteristics of the coffee tree, such as leaf dimensions, is of great importance for management of this crop, since it directly impacts on plant development. We evaluated the genetic diversity of 43 Coffea canephora genotypes and developed and compared mathematical models for estimating the leaf area of distinct genotypes using linear characteristics. Leaves from 2½ year old trees were collected from the upper middle third of the plant and the length of the central vein and maximum width of the leaf were measured; the leaf area was subsequently measured to determine real leaf area (RLA). The variables leaf length (L), leaf width (W), RLA and length x width (LW) were subjected to Pearson correlation analysis and grouped by the Tocher optimization method. All combinations were tested by linear models according to the measured parameters, and for each model R 2 was adjusted and Bayesian information criterion tested. After choosing the variable, equations were defined considering two parameters, which were ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 18 (4): gmr18486 D. Dubberstein et al. 2 subjected to cross-validation by comparing between observed x predicted areas. The 43 genotypes formed three groups according to the Tocher procedure, wherein one group was comprised of 41 genotypes. High Pearson linear correlations were found between LW x RLA (0.99), followed by W x RLA (0.95), and as such, LW best estimated the coffee leaf area; but the variable width can also be adopted, with greater ease of field measurement. The equations designed including both variables were significant at 1% and 0.1% according to the F test, and cross-validation analysis confirmed the adjustment of the equations, with equal or very similar values.