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

Abstract

KDH13 (Reg. No. GS‐10, PI 663862) is a sugarbeet (Beta vulgaris L. ssp. vulgaris) doubled haploid line 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). This line was extracted from the BCT‐resistant parental line C762‐17 (PI 560130) that segregates for BCT resistance and genetic male sterility. Intensive phenotypic screening was used to select plants from C762‐17 that showed no BCT symptoms under 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. It was confirmed a diploid by flow cytometry. This line's genome was sequenced via next‐generation sequencing, and its assembly was designated BvvSeq‐1. Homozygosity of KHD13 was confirmed using single nucleotide polymorphisms. It is monogerm and self‐fertile, and it requires at least 90 d of vernalization to induce bolting. KDH13 showed no BCT symptoms in the greenhouse and showed better resistance than commercial checks field screening experiments. In crosses with a BCT‐susceptible line, KDH13 demonstrated its suitability as a donor parent for introduction of curly top resistance genes.