Search results for "phytoplasma"
showing 10 items of 31 documents
Behavioral responses of Hyalesthes obsoletus to host-plant volatiles cues
2016
The polyphagous planthopper Hyalesthes obsoletus Signoret is considered to be the principal vector of stolbur phytoplasma, which is associated with yellow diseases of grapevine. To explore the possibility of developing novel control strategies, the behavioral responses to six synthetic mixtures and nine single compounds, previously identified from the headspace of Vitex agnus-castus L. (chaste tree) and Urtica dioica L. (nettle), were investigated in Y-tube bioassays. Choice tests revealed differences in the behavioral responses of males and females to the volatiles that they were exposed to. Males were attracted to a mixture containing (E)-β-caryophyllene, 1,8-cineole, (E,E)-α-farnesene, (…
Identification and biological traits of a planthopper from the genus Pentastiridius (Hemiptera: Cixiidae) adapted to an annual cropping rotation
2009
International audience; Cixiid planthoppers have been shown to vector phloem-limited prokaryotes associated with plant diseases world-wide. In eastern France, an emerging disease of sugar beet called syndrome basses richesses has been associated with phloem-restricted bacteria transmitted by a cixiid planthopper within the genus Pentastiridius. Early investigation suggested the species being Pentastiridius beieri. On the basis of a morphological and phylogenetic study we report the identification of the planthopper as Pentastiridius leporinus. Furthermore we report some biological traits of the species, which shows a surprising ecological adaptation to an annual cropping rotation sugar beet…
Phytoplasmosis of bioenergy cultures
2018
The current state of biofuel distribution in EU, USA and Ukraine and its perspectives, new alternative sources of renewable energy, advantages and disadvantages of their use have been analyzed in this review. The concept growing of energy cultures in Ukraine has been described. Prospects for the use of bioenergy cultures of the 2nd generation have been considered. Particular attention has been paid to advantages and peculiarities of growing cultures with high potential of productivity - willow and poplar. The role of phytoplasmas in plant pathology has been considered; the pathways of distribution of plant phytoplasmosis, their localization in plant-host cells, typical symptoms of plants af…
Data from: Survival relative to new and ancestral host plants, phytoplasma infection and genetic constitution in host races of a polyphagous insect d…
2015
Dissemination of vectorborne diseases depends strongly on the vector's host range and the pathogen's reservoir range. Because vectors interact with pathogens, the direction and strength of a vector's host shift is vital for understanding epidemiology and is embedded in the framework of ecological specialization. This study investigates survival in host-race evolution of a polyphagous insect disease vector, Hyalesthes obsoletus, whether survival is related to the direction of the host shift (from field bindweed to stinging nettle), the interaction with plant-specific strains of obligate vectored pathogens/symbionts (stolbur phytoplasma), and whether survival is related to genetic differentia…
A chromosome map of the Flavescence dorée phytoplasma
2008
International audience; The Flavescence dorée phytoplasma (FD-P), a non-cultivable, plant-pathogenic bacterium of the class Mollicutes, is the causal agent of a quarantine disease affecting vineyards of southern Europe, mainly in southern France and northern Italy. To investigate FD-P diversity and phytoplasma genetic determinants governing the FD-P life cycle, a genome project has been initiated. A physical map of the chromosome of FD-P strain FD92, purified from infected broad beans, was constructed by performing restriction digests of the chromosome and resolving the fragments by PFGE. Single and double digestions of the chromosome with the enzymes SalI, BssHII, MluI and EagI were perfor…
Development of a specific assay using RISA for detection of the bacterial agent of 'basses richesses' syndrome of sugar beet and confirmation of a Pe…
2007
International audience; A technique for the specific diagnosis in insects of SBRp (the γ-3 proteobacterium associated with the syndrome ‘basses richesses’ (SBR) of sugar beet crops in eastern France), using the RISA (rDNA intergenic spacer analysis) technique, was developed. PCR using the Alb1/Oliv1 primer pair specifically amplified a 16S-ITS region of SBRp and produced a characteristic DNA fingerprint. This PCR assay did not detect other closely related organisms, including the Arsenophonus endosymbiont of Diaphorina citri, the secondary endosymbiont of Glycaspis brimblecombei, or ‘Candidatus Phlomobacter fragariae’, a related phytopathogenic γ-3 proteobacterium. Six different ribosomal o…
Effects of Cucumber mosaic virus and Aster yellows phytoplasma (16SrI-B) on the quality of Echinacea purpurea essential oil.
2011
Echinacea purpurea Moench (L.), known as purple coneflower, is one of the most important medicinal plants, used worldwide for its immunostimulant, bacteriostatic and anti-inflammatory properties, as natural drug and/or food supplement (as infusion). In a previous study carried out in 2002 in Italy to verify possible influence of viral infectious on the plant oil composition, the oil from plants (grown at the Herb Garden of Casola Valsenio, Emilia Romagna region) infected by Cucumber mosaic virus (CMV) was compared to the one from healthy plant by combined gas chromatography mass spectrometry (GC/MS) analyses. Significant quantitative variations in their compositions were verified; the infec…
Sequence analyses of S10-spcoperon among 16SrV group phytoplasmas: phylogenetic relationships and identification of discriminating single nucleotide …
2012
Phytoplasmas are cell-wall less, uncultivable bacteria, belonging to the class Mollicutes. They parasitise both plant hosts and insect vectors, but knowledge of their biological and molecular properties is limited. In particular, analyses of 16S rDNA nucleotide sequences revealed that 16SrV group phytoplasma strains identified in grapevine plants are closely related, but associated with distinct ecologies. In this work, we investigated the evolutionary relationships of eight representative 16SrV phytoplasma strains by sequencing 15 ribosomal protein (rp) genes positioned within the S10-spc operon. Phylogenetic analyses of concatenated nucleotide and amino acid sequences underscored that 16S…
Invasion biology and host specificity of the grapevine yellows disease vector Hyalesthes obsoletus in Europe
2008
Within the past 10 years, the yellows disease ‘bois noir’ (BN) has become one of the commercially most important diseases of grapevine [ Vitis vinifera L. (Vitaceae)] in Europe. Infection pressure is caused by phytoplasmas of the stolbur 16SrXII-A group that are transmitted by a planthopper vector, Hyalesthes obsoletus Signoret (Homoptera: Auchenorrhyncha). Infestation happens as an accidental side-effect of the feeding behaviour of the vector, as vector and pathogen proliferation is dependent on other plants. In Germany, the increase of BN is correlated with the use of a new host plant by the vector, increase in abundance of the vector on the new host plant, and dissemination of host plant…
Survival relative to new and ancestral host plants, phytoplasma infection, and genetic constitution in host races of a polyphagous insect disease vec…
2014
Dissemination of vectorborne diseases depends strongly on the vector's host range and the pathogen's reservoir range. Because vectors interact with pathogens, the direction and strength of a vector's host shift is vital for understanding epidemiology and is embedded in the framework of ecological specialization. This study investigates survival in host-race evolution of a polyphagous insect disease vector, Hyalesthes obsoletus, whether survival is related to the direction of the host shift (from field bindweed to stinging nettle), the interaction with plant-specific strains of obligate vectored pathogens/symbionts (stolbur phytoplasma), and whether survival is related to genetic differentia…