Harnessing foxtail millet landraces for developing stable recombinant inbred lines with improved agronomic and nutritional traits

Foxtail millet (Setaria italica L.) is an underutilized crop with great potential for sustainable improvement especially in low input conditions like drought and low agricultural resources availability areas. Genetic variability present among the traditional land races have not been properly tapped for their use in breeding programs. In this study we used diverse foxtail millet land races and released varieties to create stable breeding populations and identify potential germplasm for improving yield and nutritional parameters. 20 landraces and four released cultivars were screened, and parents were chosen based on agronomic and nutritional trait contrasts. Controlled hybridizations were performed to make crosses between the parents. Offspring were advanced generationally. True F1 plants were identified and then were advanced from F1 to F7 generations via single seed development and generation advancement to create a fixed RIL mapping population. Large segregation for key agronomic traits was observed in the resultant RIL population, which can serve as a rich resource for selecting potential superior lines. Evaluation for Agronomic traits was carried out for key yield and yield associated traits, Iron, zinc, copper and manganese content in seeds was also assessed in the RIL population. The wide variability present in the lines showed promise for improvement of both yield and quality traits concurrently. Multiple contrasting and promising lines were selected for further work. Parental selection from landraces, combined with strategic hybridization and systematic advance generations selection has been shown to produce stable and genetically diverse breeding populations of foxtail millet in this study. The RILs developed here are a rich genetic resource to further develop cultivars with both superior agronomic traits and nutritional quality. This methodology could be used towards diversifying and improving the genetics of foxtail millet for sustainable agriculture and future food and nutritional security.
Keywords: Foxtail millet; Setaria italica; landraces; plant breeding; hybridization; parental selection; RIL population; F1–F7 generation advancement; yield improvement; nutritional quality; micronutrients; sustainable crop improvement.