Evidence of genetic diversity within Solanum Lycopersicum L. ‘Platense’ landrace and identification of various subpopulations

Abstract

Local varieties and landraces are traditional crops that have evolved over time through adaptation to their natural and cultural environment. They are presently regarded as a valuable genetic reservoir, given that most of the genetic diversity of domesticated species lies in these and other traditionally used varieties. The 'Platense' tomato landrace is adapted to the local soil and climate of the La Plata horticultural green belt, as a result of the gradual selection of a number of tomato cultivars that were introduced in Argentina towards the end of the nineteenth century following the massive immigration flow, mainly from Europe. In the present study we have evaluated the genetic identity and diversity of this landrace and all its subpopulations registered at the Germplasm Bank of the “La Consulta” Agricultural Experimental Station of INTA. The molecular analysis, based on 14 polymorphic microsatellite markers, presented a mean number of alleles per locus of 2.56 with an average polymorphic information content of 0.28. The genetic information obtained allowed the assessment of the genetic variation between and within entries, as well as the identification of all revealed genotypes with an exclusion power of over 99.99%. Likewise, the diversity was evaluated for the whole landrace, as well as for every subpopulation, establishing notably high diversity values both for the complete landrace and a number of its subpopulations. This information is highly useful in the description of the 'Platense' landrace variability and constitutes a solid approach for the genetic characterization of the available material at Germplasm Bank accessions, as well as for other eventual members of this landrace presently in use by local horticulturists.