END-USE QUALITY OF MEXICAN BREAD WHEAT FOR RAINFED AREAS. II. GENETIC VARIABILITY AND SELECTION CRITERIA

Abstract

The genetic variability and heritability of quality-related parameters and the selection criteria for bread making quality useful for breeding of mexican rainfed bread wheat (Triticum aestivum L.), were determined in a set of 15 genotypes representing diverse breadmaking quality. The evaluation was done in 11 locations which represent the environmental variability of rainfed wheat-producing area of Mexican highlands. It was found that quality traits: test weight, grain and flour protein, bread loaf volume, kernel texture, and sedimentation volume (gluten strength-related parameter), showed a very low genetic variability. Gluten extensibility (alveographs-P/L and P/G) and enzymatic activity associated with grain preharvest germination, showed intermediate genetic variability. Gluten strength (Alveograph-W) and dough mixing time showed the highest levels of genetic variability. Alveograph-W, mixing time, sedimentation volume and kernel texture showed the highest heritability values. Alveograph-W, mixing time, sedimentation volume, alveograph-P/L and alveograph-P/G, showed a positive and significative association with bread volume. Considering genetic variability and heritability, the former variables are adequate for indirect selection for improving bread-making quality.