author(s)
Ana García, Juan Pérez, Carlos Martínez and Lucía Sánchez

abstract
This study investigates the genetic basis of fruit quality in cherry tomato (Solanum lycopersicum var. cerasiforme) by mapping quantitative trait loci (QTL) associated with key traits, including soluble solids content (SSC), titratable acidity (TA), firmness, color, and volatile profiles in an F2 mapping population. The F2 progeny, derived from two contrasting cherry tomato parents, exhibited significant transgressive segregation for several traits, indicating the potential for recovering favorable alleles in breeding programs. High-density genotyping and phenotyping assessment across two growing seasons revealed several statistically significant quantitative trait loci (QTL). Notably, a major QTL for SSC was mapped near the LIN5 locus, while TA co-localized with ALMT9, and firmness was linked to a region on chromosome 10. Volatile QTL were also identified, with significant loci for hexenal, phenylacetaldehyde, and methyleugenol. The study highlights the genetic complexity of fruit quality traits and demonstrates that multiple moderate-effect loci contribute to their variation. Broad-sense heritability estimates for key traits, including SSC and firmness, were moderate to high, supporting the feasibility of marker-assisted selection for these traits. The findings also underscore the potential of cherry tomato as a model for dissecting complex traits and for developing varieties with superior flavor, texture, and aroma. This research provides a valuable foundation for future breeding programs aiming to enhance fruit quality in cherry tomato while maintaining high yield and shelf life.