Genetic diversity, population structure and genetic parameters of fruit traits in Capsicum chinense

Abstract

Abstract The fruits of Capsicum chinense stand out with a wide diversity of sizes, colors, shapes, and levels of pungency. Knowledge about this variability is essential for the success in species conservation and breeding programs. This study evaluated 65 C. chinense accessions, from different geographic regions of Brazil, for genotypic fruit traits, correlations between fruit traits, genetic parameters and diversity, population structure, and associations of AFLP markers with fruit traits. Deviance analysis showed significant differences between the accessions for all traits. Heritability in the broad sense (h2g) ranged from 0.31 (soluble solids content) to 0.90 (fruit diameter). The accuracy ​​of genotype selection was considered high (≥0.70) for most of the traits, except for soluble solids and dry matter contents (0.43 and 0.62, respectively). A high correlation between fresh and dry fruit weight was observed. However, these traits were negatively correlated with dry matter content. Soluble solids content was not correlated with any of the traits. The AFLP markers indicated high genetic variability among accessions. When the groups formed by molecular data and fruit traits were compared, no associations were observed, indicating that both stages of characterization are important. Structure analysis formed two groups, partially concordant with molecular hierarchical grouping. The AFLP markers were significantly associated with several fruit traits and considered interesting candidates for further studies.