Estimates of genetic parameters and correlations for the breeding of jambu (Acmella oleracea)

Abstract

Jambu is important nationally and internationally for its dietary and medicinal use, notably for espilanthol. Despite its versatility, breeding work is scarce. This study aimed to evaluate aerial traits and estimate genetic parameters in jambu accesses to support a breeding program. The experiment was conducted in a greenhouse at the Universidade Federal da Amazônia, Capitão Poço campus. The treatments included 172 genotype clones from seven municipalities in the Northeast mesoregion, obtained from a farmer’s market. Seedlings were cloned and transplanted after three weeks. The design was completely randomized with three replications and 20 cm × 20 cm spacing. At harvest, genotypes were manually removed and taken to the Campus Agricultural Engineering Laboratory to measure 17 aerial part traits. Variance components, genotypic values, and genetic parameters were estimated using REML/BLUP methodology. Genetic and phenotypic correlation matrices and selection gains of 75, 50, and 25% of the genotypes were calculated. Significant genetic variance and high heritability were observed for traits such as plant fresh mass, leaf fresh mass, and stem fresh mass, which are favorable for selection. Indirect selection can enhance leaf and capitula mass without significantly increasing stem diameter. Selecting 50% of the population yields good selection gains without compromising genetic variability.