TY - JA AU - Morgounov,A.I. AU - Peña-Bautista,R.J. AU - Crossa,J. AU - Rajaram,S. TI - Worldwide distribution of Glu-1 alleles in bread wheat PY - 1993/// KW - Biochemistry KW - Breadmaking KW - AGROVOC KW - Chemical composition KW - Genes KW - Molecular weight KW - Plant physiology KW - Quality KW - Triticum aestivum KW - Glutenins N1 - Peer-review: No - Open Access: No N2 - The data published on the high-molecular weight glutenin composition of bread wheat cultivars from different countries were analysed to evaluate the worldwide distribution of Glu-1 alleles and to determine the factors that affect it. In total, 1380 cultivars from 21 wheat-producing countries were included in the study. This germplasm, with few exceptions, represents the main areas of production and types of usage for particular countries. Cluster analysis based on genetic distances between the countries was applied in order to identify the similarities in distribution of Glu-1 alleles. The analysis demonstrated that Glu-1 alleles are not associated with ecogeographical parameters in a worldwide context. The composition of high-molecular weight glutenins turned out to be similar in cultivars from countries with different climatic conditions such as Finland and Yugoslavia or Italy and China. Similarity in Glu-1 composition between countries seemed to be mainly determined by similar breeding objectives with regard to bread-making quality. The intensity of selection pressure towards good quality over a long period was apparently the main factor affecting changes in Glu-1 allele frequencies. The cultivars with superior bread-making quality, i.e. having higher Glu-1 quality scores, tended to have limited variation in Glu-1 loci, thus demonstrating a narrowing of genetic variability while breeding for quality T2 - Journal of Genetics and Breeding ER -