Microsatellite variation in maize landraces from Northwestern Argentina: genetic diversity, population structure and racial aYliations

VERÓNICA V. LIA · LIDIA POGGIO · VIVIANA A. CONFALONIERI

THEORETICAL AND APPLIED GENETICS

SPRINGER

Lugar: Berlin; Año: 2009 vol. 119 p. 1053 - 1067

0040-5752

The highland region or Northwestern Argentina(NWA) is one of the southernmost areas of native maizecultivation and constitutes an expansion of the peruvianAndes sphere of inXuence. To examine the genetic diversityand racial aYliations of the landraces cultivated in this area,18 microsatellite markers were used to characterize 147individuals from 6 maize races representative of traditionalmaterials. For the whole data set, a total of 184 alleles werefound, with an average of 10.2 alleles per locus. The averagegene diversity was 0.571. The observed patterns ofgenetic diVerentiation suggest that historical association isprobably the main factor in shaping population structure forthe landraces studied here. In agreement with morphologicaland cytogenetic data, Bayesian analysis of NWA landraces revealed the occurrence of three main gene pools.Assessment of racial aYliations using a combined datasetincluding previous data on American landraces showed aclear relationship between one of these gene pools andtypical Andean races, whereas the remaining two genepools exhibited a closer association to Caribbean accessionsand native germplasm from the United States, respectively.These results highlight the importance of integratingregional genetic studies if a deeper understanding of maizediversiWcation and dispersal is to be achieved.