Parameters associated with the resistance of coffee genotypes to low temperatures

• Autor(a) principal: Rosisca, Juliandra Rodrigues
• Data de Publicação: 2022
• Outros Autores: Nagashima, Getúlio Takashi, Oliveira, Carolina Maria Gaspar de, Morais, Heverly, Sera, Gustavo Hiroshi, Caramori, Paulo Henrique, Silva, Marcelo Augusto de Aguiar e
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Semina. Ciências Agrárias (Online)
• Texto Completo: https://ojs.uel.br/revistas/uel/index.php/semagrarias/article/view/42038
• topic: Coffea racemosa; Geada; Resistência ao frio; Avaliação visual; Análises fisiológicas; Coffea racemosa; Frost; Cold resistance; Visual assessment; Physiological analysis

Physiological damage to coffee plants caused by cold stress can vary according to the intensity, exposure time, genotype, age, and nutritional status of the plants. The objective of this study was to evaluate the foliar, physiological, and biochemical damages resulting from the exposure of coffee seedlings to negative temperatures and, thus, determine the minimum lethal temperature for genotypes that could be used to study coffee plants with resistance to cold. Four progenies of Coffea arabica with introgression of Coffea racemosa, three progenies of C. arabica with introgression of Coffea liberica, and C. racemosa were evaluated, in addition to the cultivars C. arabica Mundo Novo IAC 376-4 and Catuaí Vermelho IAC 81, which were used as susceptible controls. The plants were subjected to temperatures of -2°C, -3°C, -4°C, and -5°C in a climatic growth chamber. The foliar and physiological damage of the seedlings was evaluated using qualitative (visual criterion) and quantitative methods (photosynthesis, ratio between the variable and maximum fluorescence of photosystem II [Fv/Fm], electrical conductivity of the imbibition solution of leaf disks, and protein content). The experimental design was completely randomized in a 5 × 10 factorial scheme, with five temperatures, 10 genotypes, and 4 replications. Data were subjected to analysis of variance, and means were compared using the Scott-Knott mean cluster test at 5% significance. Pearson’s correlation was performed between the means of the genotypes. Visual damage was detected at -3°C, and when correlated with the other physiological parameters, resistance was observed only in C. racemosa. Temperatures between -4°C and -5°C were the most suitable for testing cold resistance in coffee progenies.