GENETIC VARIABILITY OF ARGENTINEAN WHEAT STORAGE PROTEINS (Triticum aestivum) AND QUALITY

CUNIBERTI M. B.; RIBERI L.; VANZETTI L.; NISI M. M.; MASIERO B.; HELGUERA M.

Inglaterra

Congreso; XII ICC Cereal and Bread Congress; 2004

To estimate the genetic basis of quality in hexaploid wheats from Argentina a one-year experiment with 200 genotypes was carried out. This material was analysed for their composition at seven storage protein loci/patterns including puroindolines A-B, CNN-CS g-gliadin patterns, high molecular weight glutenin (HMWG) loci GluA1, GluB1, GluD1 and 1BL/1RS translocation. Most of the evaluated loci/patterns showed two alleles/variants (except HMWG). Genotypes were grown in three locations. Quality evaluation was carried out using seven technological tests (14 parameters): grain protein (GP), gluten content (GC), Zeleny sedimentation Test (ZT), Mixograph development time (MDT); Alveograph parameters of dough strength and tenacity (W and P),   swelling index (G), extensibility (L), ratio P/L, elasticity index (Ie); Farinograph parameters of development time (FDT), stability (FE), quality number (FQ), and bread volume (BV). Analysis of variance components was implemented to understand the effect of storage proteins in the variation of quality parameters. Location explained most of the variation in GP (80%) and GC (74%) parameters with high interaction with environment. Puroindolines played an important role explaining 61-49-45% of variation in alveogram P, W and Ie. Presence of CNN or CS g-gliadins patterns explained 20-18% of variation in farinogram FE and FQ. HMWG and 1B/1R components explained limited variation with values under 15%. The variation unexplained by genetic components ranged from 1-48%. A second analysis considering only bread wheats showed g-gliadins patterns to have  similar influence as in the previous analysis, but an increase in the role of HMWGs: GluD1 explained 33-31-21% of the variation in MDT, Ie and P/L; GluB1 explained 45-21-19-15% of the variation in L, G, ZT and W. GluA1 showed values under 15% explaining 12-10-8% of the variation in L, FDT, P and 1B/1R explained 16% of variation in ZT. A third analysis considering bread wheats with identical HMWG but differing in 1B/1R translocation, showed a significant effect on ZT (P=0.021) and MDT (P=0.037).