Genomes of the wild beets Beta patula and Beta vulgaris ssp. maritima

Plant J. 2019 Sep;99(6):1242-1253. doi: 10.1111/tpj.14413. Epub 2019 Jul 15.

Abstract

We present draft genome assemblies of Beta patula, a critically endangered wild beet endemic to the Madeira archipelago, and of the closely related Beta vulgaris ssp. maritima (sea beet). Evidence-based reference gene sets for B. patula and sea beet were generated, consisting of 25 127 and 27 662 genes, respectively. The genomes and gene sets of the two wild beets were compared with their cultivated sister taxon B. vulgaris ssp. vulgaris (sugar beet). Large syntenic regions were identified, and a display tool for automatic genome-wide synteny image generation was developed. Phylogenetic analysis based on 9861 genes showing 1:1:1 orthology supported the close relationship of B. patula to sea beet and sugar beet. A comparative analysis of the Rz2 locus, responsible for rhizomania resistance, suggested that the sequenced B. patula accession was rhizomania susceptible. Reference karyotypes for the two wild beets were established, and genomic rearrangements were detected. We consider our data as highly valuable and comprehensive resources for wild beet studies, B. patula conservation management, and sugar beet breeding research.

Keywords: Beta patula; Beta vulgaris ssp. maritima; Beta vulgaris ssp. vulgaris; comparative genomics; gene annotation; genome assembly; genome sequencing; genome structure and evolution; sugar beet; synteny display.

MeSH terms

  • Beta vulgaris / genetics*
  • Beta vulgaris / virology
  • Chromosomes / genetics
  • Crops, Agricultural / genetics
  • Genetic Variation
  • Genome, Plant*
  • Genomics
  • High-Throughput Nucleotide Sequencing
  • In Situ Hybridization, Fluorescence
  • Karyotype
  • Phylogeny
  • Plant Diseases / genetics*
  • Plant Diseases / virology
  • Synteny / genetics