Genetic diversity in durum wheat genome

BEAUFORT VALERIA; RONCALLO PABLO ; CERVIGNI GERARDO ; ECHENIQUE VIVIANA

Roma

Simposio; International Symposium Genetics and Breeding of Durum Wheat; 2013

Accademia Nazionale delle Scienze, detta dei XL, Italy; International Center for Agricultural Research in the Dry Areas (Icarda); Centro Internacional de Mejoramiento de Maíz y Trigo (Cimmyt); Italian National Research Council (CNR)

Durum wheat (Triticum turgidum L. var. durum) is used for pasta production due to the quality attributes of its grains, principally protein content, gluten strength and  yellow  color. In Argentina it is produced in the south of the province of Buenos Aires, where the elite germplasm in use was originated mainly by traditional materials from Europe and CIMMyT. Until now, studies on genetic diversity with a level of marker saturation enough for establishing the linkage desequilibrium in specific genomic regions had not been conducted. The aim of this work was to analyze the genetic diversity of  a germplasm collection of 119 durum wheat accesions using AFLP (amplified fragment length polymorphisms). The collection consists of materials from different regions (Argentina, Italy, CIMMYT, France, WANA region and USA).   Using five primer combinations 174 polymorphic out of a total of 338 loci were amplified (51.6%).  The UPGMA analysis, based on the simple matching coefficient grouped together the materials from CIMMyT but the argentinean materials did not form a defined group. The traditional argentinean genotypes grouped together with traditional italian materials, but the modern genotypes (advanced lines and commercial cultivars) constituted another group with the CIMMYT and modern italian wheats. The durum wheats of french origin formed two groups, mixed with materials from WANA region and US.   The principal coordinate analysis (PCoA) of populations by origin (subdivided into modern and traditional for argentinean and italian materials) allowed the formation of two well defined groups: one with materials from  WANA region, US and France and the other one with materials from Argentina, Italy and CIMMyT. In the last group it was possible to differenciate between traditional and modern materials. According to PCoA the three coordenates explained 92.99% of the variation (68.3, 24.7 and 4.72, respectively).   AMOVA was used to apportion variance between populations and within populations. Pairwise analysis detected significant differences between modern and traditional argentinean materials (phiPT= 0.050, p