Assessment of leaf anatomic and physiological characteristics and genetic divergence among Coffea arabica L. cultivars in the Brazilian Savanna

The knowledge on cultivars is essential for parental choosing on breeding programs. This research aimed to study the genetic divergence of Coffea arabica L. cultivars from a germoplasm bank of the Embrapa Cerrados, Brazil, for leaf anatomic and physiological characteristics. A total of 23 cultivars were evaluated: Acaia Cerrado MG1474, Araponga MG1, Catigua MG1, Catigua MG2, Catigua MG3, Catigua MG3 P4, Catigua MG3 P5, Catigua MG3 P7, Catigua MG3 P9, Catigua MG3 P23, Catigua MG3 P51, Catuai Amarelo IAC 62, Catuai Vermelho IAC 15, Catuai Vermelho IAC 81, Catuai Vermelho IAC 99, Caturra Vermelho MG0187, Guatenano Colis MG0207, Mundo Novo IAC 379-19, Paraiso MG1, Pau Brasil MG1, Sacramento MG1, San Ramon MG0198 and Topazio MG1190. In addition to the genetic divergence, the broad sense heritability and coefficient of genetic and environmental variation were also evaluated. All characteristics showed high coefficients of genetic variation and heritability values greater than 70 %, indicating a predominance of genetic over environmental factors, and that these are characteristics likely to obtain genetic gain. Catigua MG1, Catigua MG3 P51 and Topazio MG1190 stood out, with superior gas exchange characteristics. Attributes related to gas exchange were important for cultivar differentiation, demonstrating that they can be used in the early selection of Coffea arabica L. genotypes.