Avaliação do teor de cafeína em folhas e grãos de acessos de café arábica

Abstract

Resumo -O presente trabalho teve como objetivo identificar, dentro do banco de germoplasma do estado de Minas Gerais, acessos de Coffea arabica L. com baixos teores de cafeína e verificar a existência de correlação entre o teor de cafeína dos grãos e de folhas ainda no estádio de mudas, viabilizando a prática da seleção precoce. Foram utilizados 75 acessos de café (cultivares, híbridos e alguns genótipos selvagens) oriundos do banco de germoplasma de café do Estado de Minas Gerais. Para estudo da correlação foram utilizados oito cultivares no delineamento de blocos casualizados com três repetições. Avaliaram-se os teores de cafeína presentes nos grãos e no terceiro e quarto par de folhas verdadeiras. Seis acessos apresentaram teores de cafeína nos grãos menores que 0,88%. Correlações significativas para teor de cafeína foram observadas entre o terceiro (0,69) e quarto par de folhas (0,92) e os grãos. Foram identificados acessos com teores reduzidos de cafeína e boa produtividade de grãos, podendo ser utilizados como genitores em programas de melhoramento. Verificou-se que é possível realizar a seleção precoce para teor de cafeína, em plantas de cafeeiro ainda no estádio de mudas, por meio da avaliação do quarto par de folhas. Palavras-chave -Coffea arabica L. Melhoramento genético. Correlação fenotípica. Seleção precoce.Abstract -The aim of this study was to identify, within the germplasm bank of the Minas Gerais state, Coffea arabica L. accessions with low levels of caffeine and check the correlation between grain and leaves in seedling stage, making possible the practice of early selection. Seventy-five coffe accessions (cultivars, hybrids and several wild genotypes) were evaluated from the coffee germplasm bank of the Minas Gerais state. In the correlation study, eight cultivars were used on randomized complete block design with three replications. Were evaluated the caffeine levels in the grains and the third and fourth pair of true leaves. Six accessions had caffeine levels in grains smaller than 0.88%. Was also detected a significant correlation between the caffeine levels in the third (0.69) and fourth (0.92) pair of leaves and grains. Genotypes were identified with low levels of caffeine and great yield may be used as parental in breeding programs. It is possible to perform early selection for caffeine content in coffee plants, still in the seedling stage, by evaluating the fourth pair of leaves.

Resistance of genotypes and defence compounds against bacterial halo blight of coffee

“…The levels of caffeine found in the present study are similar to those reported in previous studies on Arabica coffee leaves (Ashihara et al., 1996; Rodrigues et al., 2011; Teixeira et al., 2012). The lower levels of caffeine quantified in the genotypes more resistant to BHB may be related to the fact that some substances can be converted into other derivatives and become very toxic (Barros et al., 2010; Hartleb et al., 1997).…”

Quality of coffee produced in the Southwest region of Bahia, Brazil subjected to different forms of processing and drying

“…The results also corroborate Duarte et al (2010) who found no significant difference in caffeine content between the wet and dry processing methods. However, Teixeira et al (2012) identified variations in caffeine content between different accessions of C. arabica. The uniformity of the data obtained for the caffeine content, in this study, can then be suggested by the genetic factor, since the species of coffee grown in the southwestern region of Bahia is C. Arabica, with predominance of the Catuaí cultivar.…”

Physiological quality of seeds from traditional and new recommended groups of Arabic coffee cultivars to highland regions

“…The genetic variability between cultivars can generate seeds with different sizes, densities, tegument hardness, and concentration of substances that inhibit germination, such as, caffeine and phenolic compounds. Thus, it is possible to confirm that the study of germination and vigor is something complex, as it involves numerous metabolic processes in which several factors can act simultaneously, and the whole process is controlled by the interaction between genetic and environmental factors (Teixeira, 2012;Rubim et al, 2014;Espindula, 2018;Posse et al, 2019).…”