GLUTENIN DIVERSITY OF FLOUR WHEAT (Triticum aestivum L.) FOR COOKIE QUALITY IN MEXICO

Abstract

Glutenins are high- and low-molecular-weight proteins (HMW-G and LMW-G). They play a determining role in genetic improvement to define industrial quality in flour wheat, so understanding their variability is necessary for directing selection toward a specific quality. The objective of this research was to determine the diversity of HMW-G and LMW-G alleles of genotypes from the flour wheat breeding program of the National Institute of Forestry, Agricultural, and Livestock Research (INIFAP) useful for cookie quality. Twenty-five genotypes were used, including six Mexican cookie varieties, as well as 21 genotypes introduced from an international collection of accessions from the International Maize and Wheat Improvement Center (CIMMYT). HMW-G and LMW-G were identified based on their separation on polyacrylamide gels in the presence of sodium dodecyl sulfate. For HMW-G, the 2* variant in Glu-A1 was the most frequent variant for the trial and introduction nursery, with more than 80 %. At the Glu-B1 locus, the 7+9 and 7 variants were the most frequent, with 60 and 38.1 % in trial and nursery, respectively. For Glu-D1, the 2+12 variant was the most frequent in the trial with 64 %, and 5+10 with 85.7 % in nursery. The latter allele favors baking quality. For the Glu-A1 and Glu-D1 loci, it is necessary to introduce genotypes with null alleles or with the 2+121 variant in Glu-D1 associated with cookie quality. For the highest-frequency variants of LMW-G, c in Glu-A3, h in Glu-B3, and b in Glu-D3 are associated with baking quality. With the aforementioned, it is concluded that there is a low frequency and little variation in useful alleles of HMW-G and LMW-G for cookie quality in the introduced accessions analyzed, implying that new genetic sources that favor it should be explored.