Molecular breeding as the foundation for inducing resistance to biotic stresses in sugar beet

In recent years, the integration of advances in biotechnology, genomic research, and the application of molecular markers with classical plant breeding methods has formed the basis of a multidisciplinary field called plant molecular breeding or genome-based plant breeding. This approach is widely used in breeding programs for various crops including sugar beet. The complete sequencing of the B. vulgaris genome provided a valuable tool for sugar beet genomics research. Additionally, advances in genome sequencing, the development of markers based on single nucleotide polymorphisms, and robotic methods for high-throughput genotyping have reduced the cost of genotypic evaluations for sugar beet. In Iran, the most damaging diseases affecting sugar beet include rhizomania, beet cyst nematode, root-knot nematode, and Rhizoctonia. Breeding for resistance to these diseases has been a significant focus. Over the past decades, researchers at the Iranian Sugar Beet Seed Institute and the University of Padua, Italy, have identified RAPD, SCAR, STS, and SNP molecular markers linked to resistance genes for these diseases using sugar beet mapping populations and other genotypes. In recent years, these selected markers have been used for molecular screening of thousands of single plants from various genotypes to determine the presence of the aforementioned resistance genes in breeding populations and commercial hybrids.