Genetic parameters for acerola quality traits at two maturity stages

Knowledge of genetic parameters across maturity stages can improve phenotyping and selection in acerola breeding. This study estimated genetic parameters for fruit quality traits in 35 acerola (Malpighia emarginata DC.) genotypes evaluated at the big green and red-ripe stages over two production cycles. The experiment followed a randomized complete block design with three blocks per cycle. Fruit diameter, mass, firmness, soluble solids (SS), titratable acidity (TA), SS/TA ratio, and ascorbic acid (AA) were evaluated. Variance components and genotypic values were estimated by REML/BLUP, considering cycle and blocks within cycles as fixed effects and genotype and genotype × cycle as random effects. At the big green stage, mean genotypic heritability (h²mg) was highest for mass (0.68), diameter (0.65), TA (0.61), and SS/TA (0.60), with selective accuracies of 0.78–0.83. Lower h²mg values were obtained for AA (0.37), firmness (0.13), and SS (0.03). At the red-ripe stage, h²mg ranged from 0.36 for SS to 0.69 for diameter and SS/TA, with estimates of 0.64, 0.63, 0.59, and 0.44 for TA, mass, AA, and firmness, respectively, and accuracies of 0.60–0.83. The CVg/CVe ratio exceeded 1.0 for diameter, mass, and TA at both stages, whereas firmness, SS, SS/TA, and AA exceeded 1.0 only at the red-ripe stage. Overall, fruit size traits showed favorable genetic parameters at both stages, while physicochemical and nutritional traits generally showed greater potential for genotype discrimination at the red-ripe stage. Maturity stage should therefore be considered when defining phenotyping strategies in acerola breeding.