Publications by authors named "Sandrine Eveillard"

Estimating the distance at which pathogens disperse from one season to the next is crucial for designing efficient control strategies for invasive plant pathogens and a major milestone in the reduction of pesticide use in agriculture. However, we still lack such estimates for many diseases, especially for insect-vectored pathogens, such as Flavescence dorée (FD). FD is a quarantine disease threatening European vineyards.

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The flavescence dorée phytoplasma undergoes a propagative cycle in its insect vectors by first interacting with the insect cell surfaces, primarily in the midgut lumen and subsequently in the salivary glands. Adhesion of flavescence dorée phytoplasma to insect cells is mediated by the adhesin VmpA. We hypothesize that VmpA may have lectin-like activity, similar to several adhesins of bacteria that invade the insect gut.

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Phytoplasmas inhabit phloem sieve elements and cause abnormal growth and altered sugar partitioning. However, how they interact with phloem functions is not clearly known. The phloem responses were investigated in tomatoes infected by " Phytoplasma solani" at the beginning of the symptomatic stage, the first symptoms appearing in the newly emerged leaf at the stem apex.

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Flavescence dorée (FD) is a severe epidemic disease of grapevines caused by FD phytoplasma (FDP) transmitted by the leafhopper vector . The recent sequencing of the 647-kbp FDP genome highlighted an unusual number of genes encoding ATP-dependent zinc proteases FtsH, which have been linked to variations in the virulence of " Phytoplasma mali" strains. The aims of the present study were to predict the FtsH repertoire of FDP, to predict the functional domains and topologies of the encoded proteins in the phytoplasma membrane and to measure the expression profiles in different hosts.

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Lavender decline compromises French lavender production, and preliminary data have suggested the involvement of " Phytoplasma solani" in the etiology of the disease. In order to evaluate the epidemiological role of " Phytoplasma solani," a 3-year survey was conducted in southeastern France. " Phytoplasma solani" was detected in 19 to 56% of the declining plants, depending on seasons and cultivars, and its prevalence was correlated with symptom severity.

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Flavescence dorée (FD) is a quarantine disease of grapevine, involving interactions between the plants, leafhopper vectors, and FD phytoplasma. Characterizing the susceptibility of vine varieties could limit disease propagation. After extensive surveys in vineyards, we showed that Cabernet Sauvignon (CS) is highly susceptible, with a high proportion of symptomatic branches and phytoplasma titers, in contrast to Merlot (M).

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The assembly of 20,000 sequencing reads obtained from shotgun and chromosome-specific libraries of the Spiroplasma citri genome yielded 77 chromosomal contigs totaling 1,674 kbp (92%) of the 1,820-kbp chromosome. The largest chromosomal contigs were positioned on the physical and genetic maps constructed from pulsed-field gel electrophoresis and Southern blot hybridizations. Thirty-eight contigs were annotated, resulting in 1,908 predicted coding sequences (CDS) representing an overall coding density of only 74%.

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Tomato (Lycopersicon esculentum cv. Micro-Tom) plants infected by the stolbur phytoplasma (isolate PO) display floral abnormalities, including sepal hypertrophy, virescence, phyllody, and aborted reproductive organs, which are reminiscent of those observed in Arabidopsis thaliana mutants affected in flower development genes. Semiquantitative reverse transcription-polymerase chain reaction and in situ RNA hybridization were used to compare expressions of meristem and flower development genes in healthy and stolbur phytoplasma-infected tomatoes.

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Symptoms of huanglongbing (HLB) were reported in São Paulo State (SPS), Brazil, in March 2004. In Asia, HLB is caused by 'Candidatus Liberibacter asiaticus' and in Africa by 'Candidatus Liberibacter africanus'. Detection of the liberibacters is based on PCR amplification of their 16S rRNA gene with specific primers.

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Symptoms of huanglongbing (HLB), one of the most serious diseases of citrus in Asia and Africa, have been noticed in March 2004 in the Araraquara region of São Paulo State, Brazil. HLB has not been reported previously from America. The causal HLB bacteria, Candidatus Liberibacter africanus in Africa and Candidatus Liberibacter asiaticus in Asia, can be detected in symptomatic citrus leaves by PCR amplification of their 16S rDNA with previously described primers.

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