Registration of sugar beet genetic stocks FC308 (PI701378) and FC309 (PI700990)

Authors: Todd, Olivia; Fall, Amy; Fenwick, Ann; Hanson, Linda; Richardson, Kelley; Dorn, Kevin

Submitted to: Journal of Plant Registrations
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/12/2023
Publication Date: 1/8/2024
Citation: Todd, O.E., Nielson, A.L., Fenwick, A.L., Hanson, L.E., Richardson, K.L., Dorn, K.M. 2024. Registration of sugar beet genetic stocks FC308 (PI701378) and FC309 (PI700990). Journal of Plant Registrations. https://doi.org/10.1002/plr2.20345.
DOI: https://doi.org/10.1002/plr2.20345

Interpretive Summary: American beet sugar producers face ongoing threats from multiple pests and pathogens. Sugar beet breeders have traditionally used mass selection to gradually improve resistance to pests and pathogens. USDA-ARS scientists and collaborators developed two new sugar beet lines with improved levels and uniformity of resistance to Fusarium Yellows and Sugar Beet Cyst Nematode. Utilizing molecular assisted breeding and modern genome sequencing technologies, these two new sugar beet genetic stocks provide a new resource for scientists studying plant-pest interactions and for commercial breeders aiming to develop improved commercial hybrids.

Technical Abstract: FC308 and FC309 are sugar beet (Beta vulgaris spp. vulgaris) genetic stocks released from the USDA-ARS Fort Collins Sugar Beet Genetics Lab. Unreleased seed lots from the USDA-ARS Salinas sugar beet breeding program (7927-4-309 and 3927-4-308) were used to bulk increase, screen, and select to produce germplasm with enhanced uniformity for resistance to Fusarium Yellows (FC309) and sugar beet cyst nematode (FC308). Using previously developed molecular markers linked to each resistance trait, complete homozygosity at these loci was confirmed in each line. Whole genome sequencing experiments confirm high levels of global homozygosity in each of these two new genetic stocks. The FC308 genetic stock is diploid, self-fertile, segregating for hypocotyle color and multigerm seed, with uniform tolerance to sugar beet cyst nematode, and susceptibility to Rhizoctonia Crown and Root Rot and Fusarium Yellows. The FC309 genetic stock is diploid, self-fertile, segregating for hypocotyle color and multigerm seed, has uniform strong resistance to Fusarium Yellows, and susceptibility to Rhizoctonia Crown and Root Rot and Sugar Beet Cyst Nematode. Collectively, these two new sugar beet genetic stocks represent a uniform, highly homozygous genetic background for studying the host plant resistance to Fusarium and sugar beet cyst nematode.