Registration of Sugarbeet Doubled Haploid Line KDH13 with Resistance to Beet Curly Top

Abstract

KDH13 is a sugar beet (Beta vulgaris L. ssp vulgaris) doubled haploid line (PI 663862) released as a genetic stock by USDA-ARS in cooperation with the Beet Sugar Development Foundation, Denver, CO. KDH13 is resistant to beet curly top (BCT) caused by Beet curly top virus which is transmitted by the beet leafhopper (Circulifer tenellus Baker). KDH13 was extracted from the BCT resistant C762-17 (PI 560130) parental line that segregates for BCT resistance and genetic male sterility. Intensive phenotypic screening was used for selecting plants from C762-17 that showed no symptoms under fully controlled infection conditions in the greenhouse. Seed from a single plant was used as a donor of floral buds for isolation of unfertilized ovaries to regenerate KDH13 via gynogenesis, and was confirmed a diploid by flow cytometry. The whole genome for this line was sequenced via next generation sequencing and its assembly was designated BvvSeq-1. The assembly was used to identify a large set of single nucleotide polymorphic markers (SNP) aligned to a BCT susceptible line (KWS2320) genome assembly. Homozygosity of KHD13 was confirmed using SNPs. It is a monogerm, self- fertile, and requires at least 90 days of vernalization for bolting. KDH13 outperformed BCT resistant commercial checks in greenhouse and field screening experiments. This line was used in crosses with susceptible parents and proved to be suitable as a donor parent for curly top resistance genes.