Pathogenicity and effects on transmission of a mycoplasmalike organism of a transovarially infective bacterium on the leafhopper Euscelidius variegatus (Homoptera: Cicadellidae)

Purcell, Alexander H.; Suslow, Karen

doi:10.1016/0022-2011(87)90094-2

Cited by 20 publications

(15 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although the relationship between pathogen virulence with horizontal and vertical transmission rates is complex (Lipsitch et al, 1996), it is generally agreed that parasitic infections that harm their hosts cannot be maintained by vertical transmission alone (Fine, 1975;Anderson & May, 1981). For example, the BEV bacterium is pathogenic to its leafhopper host, Euscelidius variegatus, but is transmitted horizontally between hosts through feeding on plants, as well as vertically from mother to offspring (Purcell & Suslow, 1987;Purcell et al, 1994). We have found no evidence of transmission of PASS or PAR from aphid to aphid via feeding, or coincident plant contamination, on either sweet pea (Chen & Purcell, 1997) or bur clover, and conclude that if it does occur, it must be rare.…”

Section: Discussionmentioning

confidence: 72%

Fitness effects of two facultative endosymbiotic bacteria on the pea aphid, Acyrthosiphon pisum, and the blue alfalfa aphid, A. kondoi

Chen

Montllor

Purcell

2000

Entomologia Exp Applicata

Self Cite

257

289

View full text Add to dashboard Cite

The effects of two bacterial endosymbionts, designated PASS and PAR, were evaluated on the pea aphid, Acyrthosiphon pisum (Harris) (Hemiptera:Aphididae), in which they occur facultatively, and on the blue alfalfa aphid, A. kondoi Shinji, in which these bacteria have not been found in natural populations. Subclones of pea aphids and blue alfalfa aphids, derived from parent aphid clones that did not contain PASS or PAR, were infected with one or both bacteria, generating PASS‐ and/or PAR‐positive subclones with minimal genetic differences from the parent clones. Under laboratory conditions at 20 °C, PAR consistently reduced the fecundity (by between 19 and 60%) of subclones derived from three different parent pea aphid clones on bur clover, Medicago hispida Gaertn. PAR had intermediate effects on pea aphids reared on sweet pea, Lathyrus odoratus L., and had no significant effect on pea aphids on alfalfa, Medicago sativa L. The effect of PASS was either neutral or negative, depending on parent clone as well as host plant. Also at 20 °C, PASS reduced fecundity (70–77%) and longevity (40–48%), and increased the age of first reproduction (by up to 1.5 days) of blue alfalfa aphid reared on alfalfa and clover. PAR had a less dramatic effect (e.g., 30–39% reduction in fecundity) on these traits of blue alfalfa aphid. In contrast, PAR and PASS increased the fitness of pea aphid subclones of one parent clone reared for three generations at 25 °C on each of the three test plants. Without facultative bacteria, fecundity of the parent clone was reduced to a mean total of < 6 offspring per adult at this elevated temperature, but with PASS or PAR, mean total fecundity of its subclones was > 35. However, this ameliorative effect of facultative bacteria at 25 °C was not found for two other sets of parent clones and their derived subclones. Alate production in pea aphids was significantly increased in large populations of two PASS‐ and PAR‐positive subclones relative to their parent clones. Attempts to transmit PASS or PAR horizontally, i.e., from aphid to aphid via feeding on host plants (bur clover), were unsuccessful.

show abstract

Section: Discussionmentioning

confidence: 72%

Fitness effects of two facultative endosymbiotic bacteria on the pea aphid, Acyrthosiphon pisum, and the blue alfalfa aphid, A. kondoi

Chen

Montllor

Purcell

2000

Entomologia Exp Applicata

Self Cite

257

289

View full text Add to dashboard Cite

show abstract

“…For transovarial transmission alone to perpetuate BEV in nature, BEV must evolve towards benefiting its leafhopper host. The most damaging effect of BEV on the fitness of its insect host is reduced fecundity [13]. Less virulent variants of BEV might be rapidly selected, but it is difficult to predict how or if beneficial strains might arise.…”

Section: Discussionmentioning

confidence: 99%

“…To confirm BEV infection in leafhoppers, we isolated BEV on Difco (Difco Labs., Detroit, MI) purple agar [13] acidified with 1 N hydrochloric acid to pH 6.3 and incubated in total darkness (light kills Bacterial Transmission Via Plants 21 BEV) at 24-26°C. Positive cultures were confirmed by colony growth after 4-6 days or longer, colony appearance, cell morphology, and inability to grow in light.…”

Section: Bacterial Culture and Identificationmentioning

confidence: 99%

See 1 more Smart Citation

Transmission via plants of an insect pathogenic bacterium that does not multiply or move in plants

1994

View full text Add to dashboard Cite

A bacterial parasite (designated as BEV) of the leafhopper Euscelidius variegatus, which is passed transovarially to offspring, was transmitted from insect to insect via feeding of the insects in plants. The rate of bacterial infection of leafhoppers fed upon plants that had previously been exposed to BEV-infected leafhoppers declined with an increase in the time that infected leafhoppers had been off rye grass. Transmission of BEV also occurred on sugar beet and barley but not celery. The bacterium was also transmitted to and acquired from membrane-encased artificial diets. There was no evidence that the bacterium was transmitted via plant surfaces, but transmission and direct culture assays from plants indicated that the bacterium did not multiply or move within plants. This parasite-host relationship may represent a primitive stage in either the evolution of intracellular symbiosis with its insect host or to alternative parasitization of plant and insect hosts via insect transmission, as is the case for insect-vectored plant pathogens.

show abstract

“…When tested in 1987, infected E. variegatus displayed reduced fecundity, longevity, and increased development time [34]; since then, the degree of pathogenicity may have declined, under laboratory conditions. BEV can be horizontally acquired by naïve hosts when feeding on plants in the company of infected individuals, but it does not move, replicate, or cause disease within plants [35].…”

Section: Introductionmentioning

confidence: 99%

Origin and Examination of a Leafhopper Facultative Endosymbiont

et al. 2011

View full text Add to dashboard Cite

Eukaryotes engage in intimate interactions with microbes that range in age and type of association. Although many conspicuous examples of ancient insect associates are studied (e.g., Buchneraaphidicola), fewer examples of younger associations are known. Here, we further characterize a recently evolved bacterial endosymbiont of the leafhopper Euscelidius variegatus (Hemiptera, Cicadellidae), called BEV. We found that BEV, continuously maintained in E. variegatus hosts at UC Berkeley since 1984, is vertically transmitted with high fidelity. Unlike many vertically transmitted, ancient endosymbioses, the BEV–E. variegatus association is not obligate for either partner, and BEV can be cultivated axenically. Sufficient BEV colonies were grown and harvested to estimate its genome size and provide a partial survey of the genome sequence. The BEV chromosome is about 3.8 Mbp, and there is evidence for an extrachromosomal element roughly 53 kb in size (e.g., prophage or plasmid). We sequenced 438 kb of unique short-insert clones, representing about 12% of the BEV genome. Nearly half of the gene fragments were similar to mobile DNA, including 15 distinct types of insertion sequences (IS). Analyses revealed that BEV not only shares virulence genes with plant pathogens, but also is closely related to the plant pathogenic genera Dickeya, Pectobacterium, and Brenneria. However, the slightly reduced genome size, abundance of mobile DNA, fastidious growth in culture, and efficient vertical transmission suggest that symbiosis with E. variegatus has had a significant impact on genome evolution in BEV.Electronic supplementary materialThe online version of this article (doi:10.1007/s00284-011-9893-5) contains supplementary material, which is available to authorized users.

show abstract

Pathogenicity and effects on transmission of a mycoplasmalike organism of a transovarially infective bacterium on the leafhopper Euscelidius variegatus (Homoptera: Cicadellidae)

Cited by 20 publications

References 4 publications

Fitness effects of two facultative endosymbiotic bacteria on the pea aphid, Acyrthosiphon pisum, and the blue alfalfa aphid, A. kondoi

Fitness effects of two facultative endosymbiotic bacteria on the pea aphid, Acyrthosiphon pisum, and the blue alfalfa aphid, A. kondoi

Transmission via plants of an insect pathogenic bacterium that does not multiply or move in plants

Origin and Examination of a Leafhopper Facultative Endosymbiont

Contact Info

Product

Resources

About