Mapping genes involved in durum wheat quality

A. PICCA; CONTI, V; CARRERA A; VIVIANA ECHENIQUE; ZHANG W; A. SCHLATTER; DÍAZ M; MANTHEY F; POLCI, P; MIRANDA R; NISI M; HELGUERA M; DUBCOVSKY J

Santo Domingo

Congreso; V Encuentro Latinoamericano y del Caribe de Biotecnología Agrícola, REDBIO 2004; 2004

Red Latinoamericana de Biotecnología

Durum wheat quality is mostly determined by semolina color, gluten strength and grain protein content. Yellow color is the result of a balance between accumulation of carotenoid pigments in the grain and their oxidative degradation by lipoxygenase (Lox) activity in the semolina. Grain protein content determines pasta quality and its nutritional value and is also directly related to gluten content in semolina. Gluten protein content and composition (gliadins and glutenins) as well as their interaction with the environment determine the industrial quality of durum wheat. The objectives of this work are: (1)  to develop a genetic map of durum wheat and (2)  to identify molecular markers associated to the mentioned traits. A mapping population of 94 near isogenic lines in F8 obtained from the cross UC1113 x Kofa has been developed. Biochemical (gliadins, gluenins, isozymes) and molecular markers (AFLP, RAPD, microsatellites) have been analyzed and carotene content, semolina and pasta color, pasta firmess and SDS sedimentation test were determined. Genotypes from 67 AFLP loci, 1 gliadyn, 2 glutenins, 7 RAPDs and 88 microsatellite markers have been obtained and preliminary linkage groups have been constructed using the Mapmaker program. The significant differences observed in lox activity between both parental lines opens the possibility of mapping the corresponding lox genes or their regulatory genes. Polymorphisms in additional isoenzymatic and AFLP loci are being analyzed. The results of this project will make possible the localization of genes related to quality traits and/or linked molecular markers suitable for marker assisted selection in durum wheat breeding programs.