Effect of rhizomania on red table-beet biomass production and molecular characterization of an isolate of Beet necrotic yellow vein virus from Brazil

Abstract

In Brazil, Beet necrotic yellow vein virus (BNYVV), which causes rhizomania in red table-beet (Beta vulgaris subsp. vulgaris), was first reported in 2015. This study evaluated the pathogenic effects of the disease on biomass production of red table-beet plants under field conditions. The effect of rhizomania infection depended on the season when the experiment was conducted. BNYVV infection had no effect on dry weight of aerial parts of plants growing in autumn, and a marginal effect on storage roots, reducing the weight by 27.5%. In spring, rhizomania significantly reduced the dry weight of aerial parts by 48% and the storage-root weight by 64.6%. The presence of the possible vector Polymyxa betae was confirmed by PCR and subsequent nucleotide sequencing. The near-complete genome of a BNYVV isolate from Brazil was determined using high-throughput sequencing; the homologous sequence of the RNA-5 genome segment was not identified. The BNYVV genome of the Brazilian isolate was very similar to the type BNYVV-S isolate.