Predation of the cereal aphid Sitobion avenae by polyphagous predators on the ground

AbstractPolyacrylamide gel electrophoresis of enzymes (carboxylesterases) was used for the first time to monitor rates of parasitism in airborne alate (winged) grain aphid, Sitobion avenae (F.) population samples collected by suction trapping in Hertfordshire, UK. Using previously described electrophoretic ‘keys’, the species of hymenopterous parasitoids present in individual aphids were identified and found to be Aphidius ervi (Haliday) and/or Aphidius rhopalosiphi (De Stephani Perez) (Braconidae). Entomophthoralean fungal infection was also detected using this approach. Aphidiid wasp parasitism was detected from early June to mid-August and fungal infection from late June to late July. The results are discussed in relation to parasitoid population structure and dynamics, especially (i) the fact that winged aphids passively transport the early stages of their braconid parasitoids and fungal pathogens, potentially to newly-founded colonies, which may directly impact on the dual aphid-parasitoid populations genetics; and (ii) the approach used to collect and assay parasitised and fungal infected aphids involving both suction trapping and electrophoretic testing may have potential in assessing the level and efficacy of these biological control agents in integrated pest management (IPM) schemes to combat cereal aphid outbreaks.

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Assessment of methods for estimating the numbers of aphids (Hemiptera: Aphididae) in Cereals

Bulletin of Entomological Research ◽

10.1017/s0007485300008701 ◽

1982 ◽

Vol 72 (4) ◽

pp. 675-685 ◽

Cited By ~ 25

Author(s):

Alan M. Dewar ◽

Godfrey J. Dean ◽

Ray Cannon

Keyword(s):

Field Studies ◽

Accurate Method ◽

Sitobion Avenae ◽

Cereal Aphid ◽

Metopolophium Dirhodum ◽

Aphid Density ◽

Very High ◽

Vacuum Sampling

AbstractVisual counting was found to be the most accurate method of estimating cereal aphid numbers in field studies in England. Vacuum sampling decreased in efficiency as aphid density increased, but could be a useful alternative to visual counts at very low aphid densities when the latter became too time-consuming. Cutting tillers for later washing in the laboratory was less efficient than visual counting as aphids, especially Metopolophium dirhodum (Wlk.), fell off the plants during sampling, but this method was useful in determining the proportion of different morphs of Sitobion avenae (F.) present at very high densities.

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Harbouring the secondary endosymbiont Regiella insecticola increases predation risk and reproduction in the cereal aphid Sitobion avenae

Journal of Pest Science ◽

10.1007/s10340-019-01090-z ◽

2019 ◽

Vol 92 (3) ◽

pp. 1039-1047 ◽

Cited By ~ 3

Author(s):

Guillermo E. Ramírez-Cáceres ◽

Mario G. Moya-Hernández ◽

Manuel Quilodrán ◽

Roberto F. Nespolo ◽

Ricardo Ceballos ◽

...

Keyword(s):

Predation Risk ◽

Sitobion Avenae ◽

Cereal Aphid ◽

Secondary Endosymbiont

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Seedling and adult plant resistance to Sitobion avenae (Hemiptera: Aphididae) in Triticum monococcum (Poaceae), an ancestor of wheat

Bulletin of Entomological Research ◽

10.1079/ber2003278 ◽

2004 ◽

Vol 94 (1) ◽

pp. 35-46 ◽

Cited By ~ 17

Author(s):

S.M. Migui ◽

R.J. Lamb

Keyword(s):

Plant Resistance ◽

Adult Plant Resistance ◽

Sitobion Avenae ◽

Triticum Monococcum ◽

Growth Potential ◽

Adult Plant ◽

Cereal Aphids ◽

Sources Of Resistance ◽

Cereal Aphid ◽

Overall Resistance

AbstractCereal aphids are important pests of wheat, Triticum aestivum L. and Triticum durum Desf. Crop resistance is a desirable method for managing cereal aphids in central North America, where the dominant crop, spring-sown wheat, has a low value per unit area. A diploid ancestor of wheat, Triticum monococcum L., is reported to be partially resistant to Sitobion avenae (Fabricius), the most damaging cereal aphid in the region. To identify potential sources of resistance, 42 accessions of T. monococcum and three cultivated wheats were infested with aphids, seedlings for six days and adult plants for 21 days. Overall resistance was estimated by the biomass loss of foliage and spikes in relation to uninfested control plants. Antibiosis was estimated by the gain in biomass of aphids during infestation, and tolerance was estimated as a biomass conversion ratio, overall resistance divided by antibiosis. A few T. monococcum accessions exhibited partial resistance. No relationship was found between seedling and adult plant resistance: the former exhibited primarily antibiosis and the latter primarily tolerance. Two accessions with antibiosis reduced aphid biomass by 60% compared with commercial wheats. Tolerance was correlated with growth potential, and was useful only in accessions with high growth potential. Four accessions exhibited tolerance levels at least 30% greater than commercial wheats. Highly susceptible accessions also were identified, which would be useful for investigating the inheritance of antibiosis and tolerance.

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Seasonal and annual genotypic variation and the effect of climate on population genetic structure of the cereal aphid Sitobion avenae in northern France

Bulletin of Entomological Research ◽

10.1017/s0007485307005500 ◽

2007 ◽

Vol 98 (2) ◽

pp. 159-168 ◽

Cited By ~ 13

Author(s):

C.-A. Dedryver ◽

J.-F. Le Gallic ◽

L. Haack ◽

F. Halkett ◽

Y. Outreman ◽

...

Keyword(s):

Genetic Structure ◽

Spatial Scales ◽

Genotypic Variation ◽

Reproductive Mode ◽

Genotypic Diversity ◽

Theoretical Models ◽

Sitobion Avenae ◽

Cereal Aphid ◽

Northern France ◽

High Dispersal

AbstractChanges in the genetic structure and genotypic variation of the aphid Sitobion avenae collected from cereal crops in northern France were examined by analysing variation at five microsatellite loci across several years and seasons. Little regional and temporal differentiation was detected, as shown by very low FST among populations. Repeated genotypes, significant heterozygote deficits, positive FIS values and frequent linkage disequilibria were found in nearly all samples, suggesting an overall pattern of reproductive mode variation in S. avenae populations. In addition, samples from Brittany (Bretagne) showed greater signs of asexual reproduction than those from the north of France, indicating a trend toward increasing sexuality northward. These patterns of reproductive variation in S. avenae are consistent with theoretical models of selection of aphid reproductive modes by climate. Contrasting with little changes in allelic frequencies, genotypic composition varied substantially in time and, to a lesser extent, in space. An important part of changes in genotypic arrays was due to the variation in frequency distribution of common genotypes, i.e. those that were found at several instances in the samples. Genotypic composition was also shown to vary according to climate, as genotypic diversity in spring was significantly correlated with the severity of the previous winter and autumn. We propose that the genetic homogeneity among S. avenae populations shown here across large temporal and spatial scales is the result of two forces: (i) migration conferred by high dispersal capabilities, and (ii) selection over millions of hectares of cereals (mostly wheat) bred from a narrow genetic base.

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