Variation for single sequence repeats (SSR) polymorphism in a tomato second cycle hybrid (SCH) and its parents in respect to the uniform genotypes from which they were derived

MASSO, Y.; TAZZIOLI, J; BOCCA, P.; PEREIRA DA COSTA, J.; PRATTA, G.R.

BIOCELL

INST HISTOL EMBRIOL-CONICET

Lugar: Mendoza; Año: 2012 p. 30 - 30

0327-9545

Forty nine SSR were applied to a tomato SCH and its parents, two Recombinant Inbred Lines (RIL18 and RIL1) derived from a cross among the cultivated Solanum lycopersicum cv. Caimanta (C) and the wild S. pimpinellifolium LA722 (P). These original genotypes together with the interspecific F1(CxP) had been previously characterized with the same SSR. In the first group of genotypes (RIL18, RIL1 and SCH), 41 SSR amplified. Just 26 of them were polymorphic, 22 being codominant (as expected for SSR) and 4 being dominant. In addition, 10 of the polymorphic SSR amplified two bands (6 in RIL18 and 4 in RIL1), which is not expected in homozygous genotypes. Five of the 15 monomorphic SSR had also been monomorphic in the second group of genotypes: C, P and F1(CxP). The remaining 10 monomorphic SSR had been polymorphic in the second group and represent genomic regions fixed by artificial selection during the selfing generations that allowed obtaining the RILs. Also, 6 of the SSR showing two bands in the first group had been monomorphic in the second group, these results suggesting that chromosomal rearrangements occurred during the selfing generations. Though a less levels of polymorphism was found in the first group in respect to the second one, an adequate number of SSR was selected to characterize the segregant generations of the SCH in order to validate QTLs detected in early generations derived from F1(CxP).