Abstract:

Variety pedigree contains a lot of information, including parental origin, breeding methods, genetic relationship, and so on. Studying them could reveal the evolution characteristics and rules of breeding and ultimately guide practice. The pedigrees of 326 wheat varieties from 1936 to 2017 in the history of the Sichuan Province was collected and analyzed in terms of breeding methods, parental composition, changes of high frequency parents and backbone parents, genetic contribution, distribution of translocation lines and synthetic germplasms. Over the past 80 years since 1930s, breeders have selected 387 direct parents from a large number of materials, made 256 combinations by means of cross breeding, and have released 314 varieties from them, which contributed directly to wheat breeding and production in Sichuan. Wheat breeding experienced a process from utilizing landraces, introducing foreign germplasm to creating breeding materials independently; high-frequency parents and backbone parents used for breeding gradually changed in different stage of the breeding history. Synthetic germplasms contributed greatly to wheat breeding in recent years. The consistency of breeding objectives will inevitably lead to the loss of genetic diversity and the fragility of genetic basis. In the future, the protection and utilization of genetic resources should be strengthened. In this review, the development of wheat breeding in Sichuan was summarized through pedigree analysis, in order to provide a reference for future research.

Key words: wheat breeding, pedigree, genetic contribution, genetic diversity, translocation lines, synthetic germplasm