Genetic basis of the lobedness degree in tomato fruit morphology

VAZQUEZ, DANA V.; PEREIRA DA COSTA, JAVIER H.; GODOY, FEDERICO.N.I.; CAMBIASO, VLADIMIR; RODRÍGUEZ, GUSTAVO R.

PLANT SCIENCE

ELSEVIER IRELAND LTD

Año: 2022

0168-9452

Fruit shapeis a key trait in tomato (Solanumlycopersicum L.). Since the most studies focused on proximo-distal fruitmorphology, we hypothesized that unknown QTLs for medio-lateral direction onescould be found analysing segregating populations where major shape genes arefixed. We examined the diversity of fruit morphology in medio-lateraldirection; defined divergent traits in cultivars carrying identical geneticconstitution at LC and FAS genes; and identified QTLs forlobedness degree (LD) by a QTL-seq approach. We found that LC and FAS genes were notenough to explain LD variability in a large tomato collection. Then, we derivedF2 populations crossing cultivars divergent for LD where LC and FAS were fixed (Yellow Stuffer x Heinz 1439 [F2YSxH] andVoyage x Old Brooks [F2VxOB]). By QTL-seq we identified a QTL for LDon chromosome 8 in both F2, which was validated in F2YSxHby interval mapping accounting for ~ 17% of the variability. Other two QTLs locatedon chromosomes 6 and 11 with epistasis explained ~ 61% of the variability inthe F2VxOB. In conclusion, three novel QTLs with major effect for LD(ld6, ld8, and ld11) wereidentified through the study of diversity and genetic segregation inintraspecific tomato crosses.