Diversity of Leaf Stomatal Traits among Coffea canephora Pierre ex A. Froehner Genotypes

Abstract

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.

Nutritional Balance and Genetic Diversity of Coffea canephora Genotypes

“…To increase the reliability of the dissimilarity among the grouped genotypes, the Tocher method has also been used. In the studies conducted by [ 4 , 36 , 37 , 38 , 39 ], the similarity and consistency of the methods in the formation of groups of C. canehora genotypes has been confirmed.…”

Germplasm characterization of half‐sib families from seminal matricies of Coffea canephora

“…This aptitude was expected and was confirmed given the hypothesis used in this work involving plant matrices in seminal crops. Other studies in the state have shown the wide phenotypic diversity of germplasm collections in the state, evaluating only adult plants with reports of the root system (L. Silva et al., 2020), fruit production (Partelli et al., 2021), flowering (C. Silva, Partelli, et al., 2021), stomatal characteristics (Dubberstein et al., 2021), nutrient concentration in leaves (C. Silva, Santos, et al., 2021), and traits related to the plants, branches, leaves, growing cycle, fruits, seeds, response to pests, diseases, drought, and harvest and postharvest factors (M. Ferrão et al., 2021).…”

“…The study of morphoagronomic characteristics using multivariate techniques can detect divergent and superior individuals to develop new and stable cultivars that have homogeneous development and better coffee productivity and quality (Dubberstein et al., 2021). Faced with the renewal of crops by enhanced cultivars, it is imperative that the genetic diversity be identified.…”

Biochar and Seed Priming Technique with Gallic Acid: An Approach toward Improving Morpho-Anatomical and Physiological Features of Solanum melongena L. under Induced NaCl and Boron Stresses

“…Stomata Index (SI). The stomata index (SI) was calculated by the method of Dubberstein et al 84 A cross section of a leaf about 1 mm was cut, its upper epidermis was peeled, and then the section was rinsed with distilled water and 70% ethanol three times. The cell structure of the samples was mounted in Canada balsam, and the number of stomata and epidermal cells was imaged and counted under a Nikon Eclipse E600 microscope (DS-U3, Nikon, Japan).…”