Insect Vectors (Hemiptera: Cixiidae) and Pathogens Associated with the Disease Syndrome “Basses Richesses” of Sugar Beet in France

Abstract

The syndrome “basses richesses” (SBR) is a disease of sugar beet in eastern France associated with two phloem-restricted, nonculturable plant pathogens: a stolbur phytoplasma and a γ-3 proteobacterium, here called SBR bacterium. Three planthopper (Hemiptera: Cixiidae) species were found to live near and within sugar beet fields in eastern France: Cixius wagneri, Hyalesthes obsoletus, and Pentastiridius leporinus. The role of these planthoppers in spreading the two pathogens to sugar beet was studied. Based on its abundance and high frequency of infection with the SBR bacterium, P. leporinus was considered to be the economic vector of SBR disease. C. wagneri, the primary vector of ‘Candidatus Phlomobacter fragariae’ to strawberry in western France, also was found to be infected by the SBR bacterium and to transmit the pathogen to sugar beet. Neither C. wagneri nor P. leporinus were infected by stolbur phytoplasma. Populations of H. obsoletus living on bindweed (Convolvulus arvensis) and nettle (Urtica dioica) collected near sugar beet fields did not carry the SBR bacterium, but were highly infected with two restriction fragment length polymorphism-differentiable stolbur phytoplasma isolates. In transmission assays, only the bindweed phytoplasma isolate was transmissible to and pathogenic on sugar beet. When compared with controls, the bindweed stolbur phytoplasma and SBR bacterium similarly reduced the biomass of sugar beet plants, but the phytoplasma caused greater reductions in taproot biomass and sugar content than the SBR bacterium.

Identification and biological traits of a planthopper from the genus Pentastiridius (Hemiptera: Cixiidae) adapted to an annual cropping rotation

“…Pentastiridius sp. has consistently shown to be the major vector of SBR bacterium as populations can reach very high densities in sugar beet fields (Gatineau, 2002;Sémétey, 2006;Bressan et al, 2008) with high rates of SBR bacterium infection (Sémétey et al, 2007a;Bressan et al, 2008).…”

“…(Gatineau et al, 2001Sémétey et al, 2007a, b). On the basis of recent investigations we have assigned and used the name Pentastiridius leporinus (Linnaeus, 1761) for the cixiid planthopper spreading SBR bacterium in eastern France (Arneodo et al, 2008;Bressan et al, 2008;Bressan, in press;Bressan et al, in press). However, demonstration for this taxonomic assignment has not yet been published.…”

Agronomic practices as potential sustainable options for the management of Pentastiridius leporinus (Hemiptera: Cixiidae) in sugar beet crops

“…The disease has been shown to be associated primarily with a c-3 proteobacterium, here called SBR bacterium, and secondarily with a stolbur phytoplasma (Gatineau et al 2001Sé mé tey et al 2007a,b;Bressan et al 2008). Both pathogens are transmitted to sugar beet by a cixiid planthopper, Pentastiridius leporinus (L.) which was first presumed to be Pentastiridius beieri (Wagner) (Gatineau 2002;Bressan et al 2009a).…”

Striking Diversity of vmp1 , a Variable Gene Encoding a Putative Membrane Protein of the Stolbur Phytoplasma

“…According to tuf gene typing, StolP genotype VKI is associated with nettles and genotype VKII is associated with bindweed (27), while no clear association between StolP genotypes or plant hosts and genetically distinct insect vector populations has yet been shown (22). StolP is naturally transmitted by polyphagous Fulgoromorpha planthoppers of the Cixiidae family such as Hyalesthes obsoletus Signoret (16,31,39), Pentastiridius leporinus Linnaeus (4,18), and Reptalus panzeri Löw (23). Interestingly the other phytoplasma species, members of the 16SrXII phylogenetic group, are also transmitted by Fulguromorpha planthoppers (1,30).…”