FINE MAPPING OF FS2.1, A LOCUS CONTROLLING FRUIT ELONGATION IN TOMATO

GREEN, GISELA YAEL; PEREIRA DA COSTA, JAVIER H; DELPICCOLO, CECILIA; ZORZOLI, ROXANA; RODRÍGUEZ, GUSTAVO RUBÉN

Foz do Iguazú

Congreso; 11th International Congress of Plant Molecular Biology; 2015

Tomato (Solanum lycopersicum) is an important crop member of the Solanaceae family. Fruit shape varies significantly in the germplasm and constitutes an attribute that characterizes the culinary use and general purpose of tomato. The elongated and blocky tomatoes are preferred in the processing industry. This type of morphology allows a good stability of fruits on conveyor belts during mechanical harvest and a better fit within the cans. Elongated fruit shapes can be explained by four major QTLs: ovate, sun, fs8.1 and fs2.1 1 . The Rio Grande cultivar of S. lycopersicum carries the wild-type alleles at sun and ovate and the cultivated alleles at fs8.1 and fs.2.1 loci 2,3 . The goals of this work were to fine-map fs2.1 in a population derived from the cross between Rio Grande and LA1589 of S. pimpinellifolium and to define the developmental stage of the fruit when this locus affects morphology. During two seasons, eight and seven independent recombinant plants at the bottom of chromosome 2 were used for progeny testing the fruit shape index trait (height/width ratio). Mean values for homozygous genotypes within each family were compared by t-test. The fs2.1 locus was fine-mapped to a 0.74 Kb interval in the distal part of the chromosome 2. In addition, it was demonstrated that the effect of fs2.1 is already present at anthesis.  References: 1Gonzalo and van der Knaap (2008). TAG 116: 647-656. 2Rodríguez et al. (2011). Plant Phys. 156: 275-285. 3Sun et al. (2015). J Exp Bot. doi:10.1093/jxb/erv361