IDENTIFICATION OF MOLECULAR MARKERS ASSOCIATED WITH YIELD AND QUALITY TRAITS FOR ARGENTINEAN DURUM WHEAT BREEDING PROGRAMS

PABLO RONCALLO; BEAUFORT V; AKKIRAJU P; LARSEN A; CAMARGO-ACOSTA EMILY; MIRANDA R; JENSEN C; VIVIANA ECHENIQUE

Roma

Simposio; GENETICS AND BREEDING OF DURUM WHEAT; 2013

National Agency for New Technologies, Energy and Sustainable Economic Development

Developing cultivars with high grain yield and optimal quality traits for pasta production has been the main goal of durum wheat breeding programs worldwide. The present work resumed the main results of our research group working with a bi-parental mapping population growing in different locations of the main durum wheat area of Argentina. The identification of QTL and linked markers for grain yield and yield components, phenology, gluten strength, protein and color was performed using a population of 93 RILs (UC1113 x Kofa) evaluated in six different environments from the Province of Buenos Aires. Pleiotropic regions were identified affecting two or more traits. The main QTLs affecting yield and yield components were located on chromosome 3BS, closest linked to the SSR marker gwm493, on chromosome 2BS linked to cfa2201, on chromosome 3AL linked to ksm28 and on chromosome 4AL, where two linked QTL were detected. The first two QTL (on 3Bs and 2BS) also affect heading date and/or flowering time. The main QTL affecting flour yellow color (Fb*) were located on chromosomes 4AL, 6AL and 7BL, flanked by the markers wmc219, wmc553 and cfa2040- cfa2257, respectively. The QTL on 6AL and 7BL also affect yellow pigment content, plus a 7BS QTL flanked by the marker. barc72. These  QTLs,  in addition to Psy1 genes, located on 7BL, could be a  useful  target  for  breeding  programs  aimed  at improving semolina color. Selection against high lipoxigenase activity using the deletion of the Lpx-B1.1 from Kofa,  would result in significant improvement  in  pasta  color . For gluten strenght the most important and stable QTL affecting SV (sedimentation volume) was located on chromosome 1BL (Glu-B1). Another regions affecting this trait were located on chromosomes 6AL y 6BL flanked by the SSR markers wmc553 and gwm219, respectively.Two QTLs located on 3BS and 7BL were found as affecting protein content, linked to the SSR markers barc147-gwm493 and  cfa2040- barc1073,  respectively. However, the 3BS QTL carries alleles with opposite effects between protein and yield, whereas the 7BL QTL have pleiotropic effect increasing both protein and pigment content.The flanking markers of the QTLs detected in this work could be efficient tools to select superior genotypes for the mentioned traits to improve the quality of Argentinean durum wheats.