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1
Hawkins, C. D. B., M. I. Whitecross i M. J. Aston. "Interactions between aphid infestation and plant growth and uptake of nitrogen and phosphorus by three leguminous host plants". Canadian Journal of Botany 64, nr 10 (1.10.1986): 2362–67. http://dx.doi.org/10.1139/b86-311.
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The effects of cowpea aphids (Aphis craccivora Koch) and pea aphids (Acyrthosiphon pisum (Harris)), both Homptera: Aphididae, on nitrogen (N) and phosphorus (P) uptake by and growth of cowpea (Vigna unguiculata (L.) Walp. cv. Caloona), broad bean (Vicia faba L. cv. Aquadulce), and garden pea (Pisum sativum L. cv. Victory Freezer) seedlings were investigated. After 10 days of aphid infestation, all leaf areas were significantly lower in infested plants, and plant dry weight, mean relative growth rate, and unit leaf rate were significantly lower in all plant–aphid combinations except for pea – pea aphids. The mean leaf area ratio was the same for infested and control plants indicating that infested plants did not reallocate their assimilate resources in response to aphid feeding. The accumulation of N and P as a percentage of plant dry weight did not differ between control and infested plants and was specific to the species examined. However, control plants all had greater absolute amounts of N and P after 10 days. Even though the responses of the plants to aphid feeding were similar, the accumulation of N and P appears to be a plant species specific phenomenon.
2
Hawkins, C. D. B., M. I. Whitecross i M. J. Aston. "Similarities between the effects of aphid infestation and cytokinin application on dark respiration and plant growth of legumes". Canadian Journal of Botany 66, nr 9 (1.09.1988): 1896–900. http://dx.doi.org/10.1139/b88-259.
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Cowpea (Vigna unguiculata (L.) Walp. cv. Caloona), broad bean (Vicia faba L. cv. Aquadulce), and garden pea (Pisum sativum L. cv. Victory Freezer) seedlings were infested with cowpea aphids (Aphis craccivora Koch) or pea aphids (Acyrthosiphon pisum (Harris)), both Homoptera: Aphididae, for 10 days and then infested host plant tissue was examined for foreign substances injected by the aphids. No foreign compound was detected in any of the aphid-infested plant tissues. Both aphid species were also assayed for plant growth substances, utilizing the epinastic response of tomato (Lycopersicon esculentum Mill. cv. Roma Teardrop) seedlings, and both aphid species contained plant growth substances in concentrations higher than plant physiological concentrations. Broad bean and pea seedlings were also treated with foliar and root applications of 6-benzylaminopurine to determine if there were any similarities in plant growth or respiratory responses, following aphid infestation or 6-benzylaminopurine treatment. Root respiration in 6-benzylaminopurine treated plants decreased while shoot respiration increased in a response analogous to that observed for aphid-infested tissue. However, the alternative respiratory pathway was engaged for all 6-benzylaminopurine treatments, whereas in aphid-infested plant roots and shoots it was not. Both 6-benzylaminopurine treated and aphid-infested plants displayed a loss of apical dominance. These data suggest that part of the physiological response of the plant to aphid feeding is induced by changes in the cytokinin to auxin ratio.
3
Cagáň, Ľ., i M. Barta. "Seasonal dynamics and entomophthoralean infection of the pea aphid, Acyrthosiphon pisum Harris". Plant Protection Science 37, No. 1 (1.01.2001): 17–24. http://dx.doi.org/10.17221/8363-pps.
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The seasonal dynamics of the pea aphid, Acyrthosiphon pisum Harris, and entomopathogenic fungi from the order Entomophthorales attacking the aphid were analysed in alfalfa and field pea crops during the growing seasons of 1998 and 1999 at Nitra-Malanta. In both years, pea aphid populations on pea showed a pattern with one peak, culminated at flowering and pod formation. The infestation level on alfalfa was low in both years. Entomopathogenic fungi attacking the pea aphid were identified as Erynia neoaphidis Remaudičre and Hennebert and Conidiobolus obscurus (Hall and Dunn) Remaudičre and Keller. Both pathogens infected the aphid on pea, but only E. neoaphidis was found in the alfalfa plots. Infected aphids were not found on alfalfa during 1999. The maximum levels of infected aphids on pea were 10.30% and 48.39% in 1998 and 1999, respectively. During both years alate aphids were more frequently attacked than apteral ones. Correlation coefficients indicated a positive relationship between the number of infected aphids and precipitation, but this relationship was weak or moderately strong. A strong correlation was found between the number of dead aphids and number of alate aphids counted 5 to 10 days earlier.
4
Hawkins, C. D. B., M. I. Whitecross i M. J. Aston. "The effect of short-term aphid feeding on the partitioning of 14CO2 photoassimilate in three legume species". Canadian Journal of Botany 65, nr 4 (1.04.1987): 666–72. http://dx.doi.org/10.1139/b87-089.
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The short-term effects of the feeding of cowpea aphids (Aphis craccivora Koch) and pea aphids (Acyrthosiphon pisum (Harris)), both Homoptera: Aphididae, on 14C translocation and plant growth of broadbean (Vicia faba L. cv. Aquadulce), cowpea (Vigna unguiculata (L.) Walp. cv. Caloona), and garden pea (Pisum sativum L. cv. Victory Freezer) seedlings were investigated, but not all plant–aphid combinations were utilized. Within 10 days of infestation, aphid feeding reduced the flux of translocate to the roots, changed the assimilate partitioning pattern in affected shoots, and apparently induced assimilate sources to become assimilate sinks. Cowpea aphid feeding also caused more lateral branches to be formed in broadbean. Some of these effects may be related to the imbibing of translocate by aphids, while other effects may result from a series of interactions involving substances in the saliva of aphids, plant hormones, and the assimilate ratio of sources–sinks. The amount of radioactivity found per unit weight of aphid tissue increased between days 5 and 10 in all four plant–aphid combinations. This may indicate that the nymphs were incapable of feeding on the larger phloem elements. Except for the decreased rate of translocation to the roots, the effect of aphid feeding on translocation is plant–aphid species specific.
5
Lv, Ning, Lei Wang, Wen Sang, Chang-Zhong Liu i Bao-Li Qiu. "Effects of Endosymbiont Disruption on the Nutritional Dynamics of the Pea Aphid Acyrthosiphon pisum". Insects 9, nr 4 (10.11.2018): 161. http://dx.doi.org/10.3390/insects9040161.
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Pea aphid (Acyrthosiphon pisum) is a worldwide pest that feeds exclusively on the phloem sap of numerous host plants. It harbours a well-known primary endosymbiont Buchnera aphidicola that helps to overcome the nutritional deficiency of a plant-based diet. However, how the Buchnera contributes to the nutritional and energy metabolism of its aphid host is unclear to date. In the current study, the function of Buchnera in relation to nutritional synthesis of pea aphid was investigated by disrupting the primary endosymbiont with an antibiotic rifampicin. Our findings revealed that the disruption of Buchnera led to infertility and higher loss in body mass of aphid hosts. Body length and width were also decreased significantly compared to healthy aphids. The detection of nutrition indicated that the quantity of proteins, soluble sugars, and glycogen in aposymbiotic pea aphids increased slowly with the growth of the aphid host. In comparison, the quantities of all the nutritional factors were significantly lower than those of symbiotic pea aphids, while the quantity of total lipid and neutral fat in aposymbiotic pea aphids were distinctly higher than those of symbiotic ones. Thus, we concluded that the significant reduction of the total amount of proteins, soluble sugars, and glycogen and the significant increase of neutral fats in aposymbiotic pea aphids were due to the disruption of Buchnera, which confirmed that the function of Buchnera is irreplaceable in the pea aphid.
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Hawkins, C. D. B., M. J. Aston i M. I. Whitecross. "Aphid-induced changes in growth indices of three leguminous plants: unrestricted infestation". Canadian Journal of Botany 63, nr 12 (1.12.1985): 2454–59. http://dx.doi.org/10.1139/b85-351.
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The effects of various densities of cowpea aphids (Aphis craccivora Koch) and pea aphids (Acyrthosiphon pisum Harris), both Homoptera: Aphididae, on the growth of cowpea (Vigna unguiculata (L.) Walp. cv. Caloona), broad bean (Vicia faba L. cv. Aquadulce), and garden pea (Pisum sativum L. cv. Victory Freezer) seedlings were investigated. Within 10 days of infestation, aphid feeding significantly reduced plant dry weights and mean relative growth rates for the six plant–aphid combinations. In all cases except one, the mean unit leaf or net assimilation rate was also significantly reduced within 10 days. The mean leaf area ratio was the same for infested and control plants. The aphid-induced changes in host plants appear to be due to changes in photosynthesis, respiration, and translocate removal from the phloem over the 10-day period. Changes in the growth patterns of the host plant within this period are similar, but the underlying physiological effects could vary among particular plant–aphid combinations.
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Fazalova, Varvara, i Bruno Nevado. "Low Spontaneous Mutation Rate and Pleistocene Radiation of Pea Aphids". Molecular Biology and Evolution 37, nr 7 (12.03.2020): 2045–51. http://dx.doi.org/10.1093/molbev/msaa066.
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Abstract Accurate estimates of divergence times are essential to understand the evolutionary history of species. It allows linking evolutionary histories of the diverging lineages with past geological, climatic, and other changes in environment and shed light on the processes involved in speciation. The pea aphid radiation includes multiple host races adapted to different legume host plants. It is thought that diversification in this system occurred very recently, over the past 8,000–16,000 years. This young age estimate was used to link diversification in pea aphids to the onset of human agriculture, and led to the establishment of the pea aphid radiation as a model system in the study of speciation with gene flow. Here, we re-examine the age of the pea aphid radiation, by combining a mutation accumulation experiment with a genome-wide estimate of divergence between distantly related pea aphid host races. We estimate the spontaneous mutation rate for pea aphids as 2.7×10-10 per haploid genome per parthenogenic generation. Using this estimate of mutation rate and the genome-wide genetic differentiation observed between pea aphid host races, we show that the pea aphid radiation is much more ancient than assumed previously, predating Neolithic agriculture by several hundreds of thousands of years. Our results rule out human agriculture as the driver of diversification of the pea aphid radiation, and call for re-assessment of the role of allopatric isolation during Pleistocene climatic oscillations in divergence of the pea aphid complex.
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Yao, Lu, Senshan Wang, Rui Ma, Jiangwen Wei, Liwen Song i Lei Liu. "Functional Analysis of Amino Acid Transporter Genes ACYPI000536 and ACYPI004320 in Acyrthosiphon pisum". Insects 15, nr 1 (31.12.2023): 20. http://dx.doi.org/10.3390/insects15010020.
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In recent years, pea aphids have become major pests of alfalfa. Our previous study found that “Gannong 5” is a highly aphid-resistant alfalfa variety and that “Lie Renhe” is a susceptible one. The average field susceptibility index of “Gannong 5” was 31.31, and the average field susceptibility index of “Lie Renhe” was 80.34. The uptake and balance of amino acids in insects are usually dependent on amino acid transporters. RT-qPCR was used to detect the relative expression levels of seven amino acid transporter differential genes in the different instar pea aphids fed on resistant and susceptible alfalfa varieties after 24 h, and two key genes were selected. When pea aphids fed on “Gannong 5”, the expression of ACYPI004320 was significantly higher than that in pea aphids fed on “Lie Renhe”; however, the expression of ACYPI000536 was significantly lower than that in pea aphids fed on “Lie Renhe”. Afterward, the RNA interference with pea aphid ACYPI000536 and ACYPI004320 genes was performed using a plant-mediated method, and gene function was verified via liquid chromatography–mass spectrometry and pea aphid sensitivity to aphid-resistant and susceptible alfalfa varieties. The results showed that the down-regulation of the ACYPI000536 gene expression led to an increase in the histidine and lysine contents in pea aphids, which, in turn, led to an increase in mortality when pea aphids fed on the susceptible variety “Lie Renhe”. The down-regulation of the ACYPI004320 gene expression led to an increase in phenylalanine content in pea aphids, which, in turn, led to a decrease in mortality when pea aphids fed on the resistant variety “Gannong 5”.
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Hamada, A. M., J. Fatehi i L. M. V. Jonsson. "Seed treatments with thiamine reduce the performance of generalist and specialist aphids on crop plants". Bulletin of Entomological Research 108, nr 1 (5.06.2017): 84–92. http://dx.doi.org/10.1017/s0007485317000529.
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AbstractThiamine is a vitamin that has been shown to act as a trigger to activate plant defence and reduce pathogen and nematode infection as well as aphid settling and reproduction. We have here investigated whether thiamine treatments of seeds (i.e. seed dressing) would increase plant resistance against aphids and whether this would have different effects on a generalist than on specialist aphids. Seeds of wheat, barley, oat and pea were treated with thiamine alone or in combination with the biocontrol bacteriaPseudomonas chlororaphisMA 342 (MA 342). Plants were grown in climate chambers. The effects of seed treatment on fecundity, host acceptance and life span were studied on specialist aphids bird cherry-oat aphid (Rhopalosiphum padiL.) and pea aphid (Acyrthosiphon pisumHarris) and on the generalist green peach aphid (Myzus persicae, Sulzer). Thiamine seed treatments reduced reproduction and host acceptance of all three aphid species. The number of days to reproduction, the length of the reproductive life, the fecundity and the intrinsic rate of increase were found reduced for bird cherry-oat aphid after thiamine treatment of the cereal seeds. MA 342 did not have any effect in any of the plant-aphid combinations, except a weak decrease of pea aphid reproduction on pea. The results show that there are no differential effects of either thiamine or MA 342 seed treatments on specialist and generalist aphids and suggest that seed treatments with thiamine has a potential in aphid pest management.
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Mondor, Edward B., i Bernard D. Roitberg. "Pea aphid, Acyrthosiphon pisum, cornicle ontogeny as an adaptation to differential predation risk". Canadian Journal of Zoology 80, nr 12 (1.12.2002): 2131–36. http://dx.doi.org/10.1139/z02-209.
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Aphids possess unique anatomical structures called cornicles through which a defensive secretion containing alarm pheromone is often emitted when a predator attacks an aphid. The levels of alarm pheromone in cornicle droplets from the pea aphid, Acyrthosiphon pisum (Harris), vary considerably during development; however, it is not clear how the length of the cornicle changes during ontogeny. The length of the cornicle relative to the lengths of other body structures may have profound effects on aphid defense and alarm signal diffusion. Using previously published morphological measurements of pea aphids and observing interactions between pea aphids and multicolored Asian ladybird beetles, Harmonia axyridis Pallas, it was observed that pea aphid cornicles elongate proportionally more than other body parts during the first four instars, when alarm-pheromone levels have peaked, than during the fifth (adult) instar, when pheromone levels decline. Pea aphids also are more likely to emit cornicle droplets and daub them onto a predator when the cornicles are undergoing such rapid growth. We suggest that because of a high risk of predation, rapid cornicle growth in juveniles has evolved both for individual defense and for the inclusive fitness benefits of alarm signaling.
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Hendry, Tory A., Kelley J. Clark i David A. Baltrus. "A highly infective plant-associated bacterium influences reproductive rates in pea aphids". Royal Society Open Science 3, nr 2 (luty 2016): 150478. http://dx.doi.org/10.1098/rsos.150478.
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Pea aphids, Acyrthosiphon pisum , have the potential to increase reproduction as a defence against pathogens, though how frequently this occurs or how infection with live pathogens influences this response is not well understood. Here we determine the minimum infective dose of an environmentally common bacterium and possible aphid pathogen, Pseudomonas syringae , to determine the likelihood of pathogenic effects to pea aphids. Additionally, we used P. syringae infection to investigate how live pathogens may alter reproductive rates. We found that oral bacterial exposure decreased subsequent survival of aphids in a dose-dependent manner and we estimate that ingestion of less than 10 bacterial cells is sufficient to increase aphid mortality. Pathogen dose was positively related to aphid reproduction. Aphids exposed to low bacterial doses showed decreased, although statistically indistinguishable, fecundity compared to controls. Aphids exposed to high doses reproduced significantly more than low dose treatments and also more, but not significantly so, than controls. These results are consistent with previous studies suggesting that pea aphids may use fecundity compensation as a response to pathogens. Consequently, even low levels of exposure to a common plant-associated bacterium may therefore have significant effects on pea aphid survival and reproduction.
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Kunert, G., K. Schmoock-Ortlepp, U. Reissmann, S. Creutzburg i W. W. Weisser. "The influence of natural enemies on wing induction in Aphis fabae and Megoura viciae (Hemiptera: Aphididae)". Bulletin of Entomological Research 98, nr 1 (13.12.2007): 59–62. http://dx.doi.org/10.1017/s0007485307005391.
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AbstractPrevious studies have shown that the aphid species, Aphis fabae Scopoli and Megoura viciae Buckton, do not produce winged offspring in the presence of natural enemies, in contrast to results for the pea aphid (Acyrthosiphon pisum (Harris)) and the cotton aphid (Aphis gossypii Glover); but these studies did not involve exposing aphids directly to natural enemies. We exposed colonies of both A. fabae and M. viciae to foraging lacewing (Chrysoperla carnea (Stephens)) larvae and found that the predators did not induce winged morphs among offspring compared to unexposed controls. Colonies of A. fabae responded to an increase in aphid density with increasing winged morph production, while such response was not found for M. viciae. We suggest that different aphid species differ in their susceptibility to natural enemy attack, as well as in their sensitivity to contact.
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El Fakhouri, Karim, Abdelhadi Sabraoui, Zakaria Kehel i Mustapha El Bouhssini. "Population Dynamics and Yield Loss Assessment for Pea Aphid, Acyrthosiphon pisum (Harris) (Homoptera: Aphididae), on Lentil in Morocco". Insects 12, nr 12 (30.11.2021): 1080. http://dx.doi.org/10.3390/insects12121080.
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Pea aphid (Acyrthosiphon pisum Harris) is the major insect pest of lentil in Morocco. We investigated pea aphid mean numbers and yield losses on three lentil varieties at one location during three successive cropping seasons during 2015–2018. The effects of several weather factors on pea aphid population dynamics were investigated. Population density increased in early spring followed by several peaks during March–April and then steeply declined during the late spring. Aphid populations peaked at different times during the three years of the study. In 2016, higher populations occurred during the second and third weeks of April for Abda and Zaria varieties with averages of 27 and 28 aphids/20 twigs, respectively. In 2017, higher populations occurred on the 12th and 13th standard meteorological weeks (SMWs) for Zaria with averages of 24.7 and 27.03 aphids/20 twigs, respectively. In 2018, the population peaked for all varieties at three different times, 11th, 13th, and 17th SMW, with the highest for Zaria being 26.00, 47.41, and 32.33 aphids/20 twigs. Pea aphid population dynamics changed with weather conditions. The number of aphids significantly and positively correlated with maximum temperature, but significantly negatively correlated with relative humidity and wind speed. The minimum temperature and rainfall had non-significant correlations. Pea aphid infestation resulted in losses of total seed weight for all lentil varieties, with the highest avoidable losses for Bakria being 12.51% followed by Zaria with 7.72% and Abda with 4.56%. These losses may justify the development of integrated management options for control of this pest.
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Ingerslew, Kathryn S., i Deborah L. Finke. "Non-consumptive effects stabilize herbivore control over multiple generations". PLOS ONE 15, nr 11 (10.11.2020): e0241870. http://dx.doi.org/10.1371/journal.pone.0241870.
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Understanding the factors that influence predator-prey dynamics requires an investigation of oscillations in predator and prey population sizes over time. However, empirical studies are often performed over one or fewer predator generations. This is particularly true for studies addressing the non-consumptive effects of predators on prey. In a previous study that lasted less than one predator generation, we demonstrated that two species of parasitoid wasps additively suppressed aphid populations through a combination of consumptive and non-consumptive effects. However, the non-consumptive effects of one wasp reduced the reproductive success of the other, suggesting that a longer-term experiment may have revealed antagonism between the wasps. The goal of our current study is to evaluate multi-generation consumptive and non-consumptive interactions between pea aphids (Acyrthosiphon pisum) and the wasps Aphidius ervi and Aphidius colemani. Aphidius ervi is a common natural enemy of pea aphids. Aphidius colemani is a non-consumptive enemy that does not consume pea aphids, but negatively affects pea aphid performance through behavioral disturbance. Large field cages were installed to monitor aphid abundance in response to the presence and absence of both species of wasp over four weeks (two parasitoid generations). We found that the non-consumptive enemy A. colemani initially controlled the pea aphid population, but control in the absence of parasitism was not sustainable over the long term. Aphidius ervi suppressed pea aphids through a combination of consumptive and non-consumptive effects. This suppression was more effective than that of A. colemani, but aphid abundance fluctuated over time. Suppression by A. ervi and A. colemani together was complementary, leading to the most effective and stable control of pea aphids. Therefore, promoting a diverse natural enemy community that contributes to pest control through consumptive and non-consumptive interactions may enhance the stability of herbivore population suppression over time.
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Boulding, Elizabeth Grace. "Molecular evidence against phylogenetically distinct host races of the pea aphid (Acyrthosiphon pisum)". Genome 41, nr 6 (1.12.1998): 769–75. http://dx.doi.org/10.1139/g98-094.
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Pea aphid (Acyrthosiphon pisum) clones have been shown to be adapted to particular host plant species but it is unknown whether there are host races. A 1101 base pair region of the mitochondrial cytochrome oxidase I gene (COI) was sequenced for 21 pea aphid clones that had been collected from different host plants in Canada and the U.S.A. Only five closely related mitochondrial haplotypes were found. A maximum likelihood phylogeny was estimated for these five haplotypes and four related aphid species: Acyrthosiphon macrosiphum, A. kondoi, Fimbriaphis fimbriata, and Macrosiphum creelii. Pea aphids from the same host plant species were no more likely to have the same mitochondrial haplotype than aphids from different host plant species. In addition, aphids from the same geographical regions were no more likely to have the same mitochondrial haplotype than aphids from different geographic regions. I therefore reject the hypothesis that there are monophyletic host races of the pea aphid.Key words: cytochrome oxidase I, exotic species, host plant, mtDNA sequence, phylogeny.
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Jing, Xiangfeng, Thomas A. White, Xiaowei Yang i Angela E. Douglas. "The molecular correlates of organ loss: the case of insect Malpighian tubules". Biology Letters 11, nr 5 (maj 2015): 20150154. http://dx.doi.org/10.1098/rsbl.2015.0154.
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Malpighian tubules play an essential role in excretion, osmoregulation and immunity of most insects. Exceptionally, aphids lack Malpighian tubules, providing the opportunity to investigate the fate of genes expressed in an organ that has undergone evolutionary reduction and loss. Making use of the sequenced genomes of Drosophila melanogaster and the pea aphid Acyrthosiphon pisum , we demonstrated that more than 50% of Drosophila genes expressed specifically in the Malpighian tubules had orthologues in the pea aphid genome and that most of the pea aphid orthologues with detectable expression were identified in the gut transcriptome. Relative to the whole genome, genes functioning in amino acid metabolism are significantly over-represented among the pea aphid orthologues of Malpighian tubule genes, likely reflecting the central importance of amino acid acquisition and metabolism in aphids. This study demonstrates that the evolutionary loss of a key insect organ, the Malpighian tubules, has not been associated with the coupled loss of molecular functions.
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Haynes, S., A. C. Darby, T. J. Daniell, G. Webster, F. J. F. van Veen, H. C. J. Godfray, J. I. Prosser i A. E. Douglas. "Diversity of Bacteria Associated with Natural Aphid Populations". Applied and Environmental Microbiology 69, nr 12 (grudzień 2003): 7216–23. http://dx.doi.org/10.1128/aem.69.12.7216-7223.2003.
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ABSTRACT The bacterial communities of aphids were investigated by terminal restriction fragment length polymorphism and denaturing gradient gel electrophoresis analysis of 16S rRNA gene fragments generated by PCR with general eubacterial primers. By both methods, theγ -proteobacterium Buchnera was detected in laboratory cultures of six parthenogenetic lines of the pea aphid Acyrthosiphon pisum and one line of the black bean aphid Aphis fabae, and one or more of four previously described bacterial taxa were also detected in all aphid lines except one of A. pisum. These latter bacteria, collectively known as secondary symbionts or accessory bacteria, comprised three taxa of γ-proteobacteria (R-type [PASS], T-type [PABS], and U-type [PAUS]) and a rickettsia (S-type [PAR]). Complementary analysis of aphids from natural populations of four aphid species (A. pisum [n= 74], Amphorophora rubi [n= 109], Aphis sarothamni [n= 42], and Microlophium carnosum [n= 101]) from a single geographical location revealed Buchnera and up to three taxa of accessory bacteria, but no other bacterial taxa, in each aphid. The prevalence of accessory bacterial taxa varied significantly among aphid species but not with the sampling month (between June and August 2000). These results indicate that the accessory bacterial taxa are distributed across multiple aphid species, although with variable prevalence, and that laboratory culture does not generally result in a shift in the bacterial community in aphids. Both the transmission patterns of the accessory bacteria between individual aphids and their impact on aphid fitness are suggested to influence the prevalence of accessory bacterial taxa in natural aphid populations.
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Stokes, Bradley S., Edward J. Bechinski i Sanford D. Eigenbrode. "Economic injury levels for pea aphids (Hemiptera: Aphididae) as direct pests of commercial dry peas (Fabaceae) during reproductive growth stages in the Pacific Northwest of North America". Canadian Entomologist 151, nr 3 (29.03.2019): 365–77. http://dx.doi.org/10.4039/tce.2019.10.
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AbstractEmpirically-based economic injury levels are lacking for pea aphid, Acyrthosiphon pisum Harris (Hemiptera: Aphididae), as a direct pest of dry peas, Pisum sativum Linnaeus (Fabaceae). To address this need, the relationship between pea aphid density and yield of dry pea (cultivar Aragorn) were quantified by encaging pea aphids at varying densities for 17-day infestation periods during 2009 and 2010 in Moscow, Idaho, United States of America. Pea aphid density after infestation at the early reproductive stage of the crop (x) significantly reduced dry pea seed yield (relative weight of US #1 dry peas, y): y = 0.7733 − 0.00998x + 0.000037x2. Economic injury levels were computed based on this relationship and incorporating the cost of control, crop market value, insecticide efficacy, and crop yield potential. The resulting economic injury levels ranged from five to 19 pea aphids per plant at the start of early reproductive growth stages of dry peas. For usability these were converted to sweep net sample size equivalents of 86–307 pea aphids per twenty-five 180-degree sweeps with a standard sweep net. These economic injury levels are applicable in the inland Pacific Northwest, United States of America, where they were developed and likely in other regions with similar climatic and agronomic conditions.
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Tian, Ruizheng, Yixiao Huang, Balachandar Balakrishnan i Maohua Chen. "Gene Expression Profiling Indicated Diverse Functions and Characteristics of Core Genes in Pea Aphid". Insects 11, nr 3 (15.03.2020): 186. http://dx.doi.org/10.3390/insects11030186.
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The pea aphid is a global insect pest, and variable phenotypes can be produced by pea aphids in the same genotype in response to changes in external environmental factors. However, detailed dynamic gene regulation networks and the core markers involved in different biological processes of pea aphids have not yet been reported. In this study, we obtained the published genomic and transcriptomic data, and performed transcriptome profiling of five pea aphid morphs (winged asexual female, wingless asexual female, wingless sexual female, winged male and wingless male) from each of three pea aphid genotypes, i.e., the transcriptomes from a total of 15 types of pea aphids were analyzed and the type-specific expression of genes in five different morphs was identified. The expression profiling was verified by quantitative real-time PCR (qPCR) analysis. Moreover, we determined the expression features and co-expression networks of highly variable genes. We also used the ARACNe method to obtain 263 core genes related to different biological pathways. Additionally, eight of the identified genes were aligned with transcription factor families, indicating that they act as transcription factors and regulate downstream genes. Furthermore, we found reliable markers using random forest methodology to distinguish different morphs of pea aphids. Our study provides a systematic and comprehensive approach for analyzing the core genes that may play important roles in a multitude of biological processes from the insect transcriptomes.
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Liu, Xiaomi, Erica L. Culbert i Jennifer A. Brisson. "Male-Biased microRNA Discovery in the Pea Aphid". Insects 12, nr 6 (8.06.2021): 533. http://dx.doi.org/10.3390/insects12060533.
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Epigenetic mechanisms modulate gene expression levels during development, shaping how a single genome produces a diversity of phenotypes. Here, we begin to explore the epigenetic regulation of sexual dimorphism in pea aphids (Acyrthosiphon pisum) by focusing on microRNAs. Previous analyses of microRNAs in aphids have focused solely on females, so we performed deep sequencing of a sample containing early-stage males. We used this sample, plus samples from Genbank, to find 207 novel pea aphid microRNA coding loci. We localized microRNA loci to a chromosome-level assembly of the pea aphid genome and found that those on the X chromosome have lower overall expression compared to those on autosomes. We then identified a set of 19 putative male-biased microRNAs and found them enriched on the X chromosome. Finally, we performed protein-coding RNA-Seq of first instar female and male pea aphids to identify genes with lower expression in males. 10 of these genes were predicted targets of the 19 male-biased microRNAs. Our study provides the most complete set of microRNAs in the pea aphid to date and serves as foundational work for future studies on the epigenetic control of sexual dimorphism.
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Paulmann, Maria K., Linus Wegner, Jonathan Gershenzon, Alexandra C. U. Furch i Grit Kunert. "Pea Aphid (Acyrthosiphon pisum) Host Races Reduce Heat-Induced Forisome Dispersion in Vicia faba and Trifolium pratense". Plants 12, nr 9 (6.05.2023): 1888. http://dx.doi.org/10.3390/plants12091888.
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Although phloem-feeding insects such as aphids can cause significant damage to plants, relatively little is known about early plant defenses against these insects. As a first line of defense, legumes can stop the phloem mass flow through a conformational change in phloem proteins known as forisomes in response to Ca2+ influx. However, specialized phloem-feeding insects might be able to suppress the conformational change of forisomes and thereby prevent sieve element occlusion. To investigate this possibility, we triggered forisome dispersion through application of a local heat stimulus to the leaf tips of pea (Pisum sativum), clover (Trifolium pratense) and broad bean (Vicia faba) plants infested with different pea aphid (Acyrthosiphon pisum) host races and monitored forisome responses. Pea aphids were able to suppress forisome dispersion, but this depended on the infesting aphid host race, the plant species, and the age of the plant. Differences in the ability of aphids to suppress forisome dispersion may be explained by differences in the composition and quantity of the aphid saliva injected into the plant. Various mechanisms of how pea aphids might suppress forisome dispersion are discussed.
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Soroka, J. J., i P. A. Mackay. "SEASONAL OCCURRENCE OF THE PEA APHID, ACYRTHOSIPHON PISUM (HARRIS) (HOMOPTERA: APHIDIDAE), ON CULTIVARS OF FIELD PEAS IN MANITOBA AND ITS EFFECTS ON PEA GROWTH AND YIELD". Canadian Entomologist 122, nr 3 (czerwiec 1990): 503–13. http://dx.doi.org/10.4039/ent122503-5.
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AbstractPopulations of pea aphid, Acyrthosiphon pisum (Harris), were sampled through the summer of 1984 on five cultivars and in 1985 and 1986 on six cultivars of field peas, Pisum sativum L., grown in field plots in southern Manitoba. Patterns of pea aphid population growth were generally similar among cultivars in any one year. Aphid populations on all cultivars in all years remained relatively low until mid-July, then increased rapidly, peaked at about the beginning of August, and declined sharply to low levels in late August. At the time of peak aphid numbers, significant differences in aphid population densities were found among cultivars in 2 years; the lowest densities were found on the cultivars Century and Tipu, and the highest densities on Triumph or Trapper. Pea aphid feeding was not detrimental to any yield parameters except 1000 seed weight. In 1984 Triumph and Tara, and in 1985 Triumph had significantly decreased 1000 seed weights in plots in which aphid densities were not controlled. Differences in the abundance of the aphid among cultivars were not reflected in their yield responses. Over 3 years the regression line of aphid densities upon Century seed weight was significantly steeper than those of Trapper, Lenca, or Tara. Trapper was least affected by aphid feeding. Results indicated that the economic threshold of pea aphids on peas other than Century needs to be re-evaluated.
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Li, Yang, i Shin-ichi Akimoto. "Self and non-self recognition affects clonal reproduction and competition in the pea aphid". Proceedings of the Royal Society B: Biological Sciences 288, nr 1953 (30.06.2021): 20210787. http://dx.doi.org/10.1098/rspb.2021.0787.
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The spatial interaction of clonal organisms is an unsolved but crucial topic in evolutionary biology. We evaluated the interactions between aphid clones using a colour mutant (yellow) and an original (green) clone. Colonies founded by two aphids of the same clone and mixed colonies, founded by a green aphid and a yellow aphid, were set up to observe population growth for 15 days. We confirmed positive competition effects, with mixed colonies increasing in size more rapidly than clonal colonies. In mixed colonies where reproduction started simultaneously, green aphids overwhelmed yellow aphids in number, and yellow aphids restrained reproduction. However, when yellow aphids started to reproduce earlier, they outnumbered the green aphids. To test whether aphids have the ability to control reproduction according to the densities of self and non-self clones, one yellow aphid or one antennae-excised yellow aphid was transferred into a highly dense green clone colony. Intact yellow aphids produced fewer nymphs in crowded green colonies, whereas the fecundity of antennae-excised aphids did not change. Thus, we conclude that aphid clones can discriminate between self and non-self clones, and can regulate their reproduction, depending on whether they are superior or inferior in number to their competitors.
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Holtkamp, RH, i AD Clift. "Establishment of three species of lucerne aphids on 24 cultivars of lucerne". Australian Journal of Agricultural Research 44, nr 1 (1993): 53. http://dx.doi.org/10.1071/ar9930053.
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A field trial involving 24 cultivars of lucerne was naturally infested by three species of aphids, Therioaphis trifolii (Monell) f. maculata, spotted alfalfa aphid, Acyrthosiphon kondoi Shinji, bluegreen aphid and A. pisurn (Harris), pea aphid. Aphid establishment was found to be related to the lucerne aphid resistance ratings of these cultivars. These observations suggest that both antixenosis and antibiosis resistance mechanisms are operating.
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McLean, A. H. C., M. van Asch, J. Ferrari i H. C. J. Godfray. "Effects of bacterial secondary symbionts on host plant use in pea aphids". Proceedings of the Royal Society B: Biological Sciences 278, nr 1706 (15.09.2010): 760–66. http://dx.doi.org/10.1098/rspb.2010.1654.
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Aphids possess several facultative bacterial symbionts that have important effects on their hosts' biology. These have been most closely studied in the pea aphid ( Acyrthosiphon pisum ), a species that feeds on multiple host plants. Whether secondary symbionts influence host plant utilization is unclear. We report the fitness consequences of introducing different strains of the symbiont Hamiltonella defensa into three aphid clones collected on Lathyrus pratensis that naturally lack symbionts, and of removing symbionts from 20 natural aphid–bacterial associations. Infection decreased fitness on Lathyrus but not on Vicia faba , a plant on which most pea aphids readily feed. This may explain the unusually low prevalence of symbionts in aphids collected on Lathyrus . There was no effect of presence of symbiont on performance of the aphids on the host plants of the clones from which the H. defensa strains were isolated. Removing the symbiont from natural aphid–bacterial associations led to an average approximate 20 per cent reduction in fecundity, both on the natural host plant and on V. faba , suggesting general rather than plant-species-specific effects of the symbiont. Throughout, we find significant genetic variation among aphid clones. The results provide no evidence that secondary symbionts have a major direct role in facilitating aphid utilization of particular host plant species.
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Soroka, J. J., i P. A. Mackay. "POPULATION GROWTH OF THE PEA APHID, ACYRTHOSIPHON PISUM (HARRIS) (HOMOPTERA: APHIDIDAE), AND PLANT RESPONSE TO APHID NUMBERS IN COMMERCIALLY GROWN FIELD PEAS IN MANITOBA". Canadian Entomologist 122, nr 6 (grudzień 1990): 1201–10. http://dx.doi.org/10.4039/ent1221201-11.
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AbstractPea aphids, Acyrthosiphon pisum (Harris), were sampled weekly or biweekly over the summers of 1985 and 1986 in a total of 15 commercial plantings of Century, Trapper, or Triumph field peas across Manitoba. Pea aphid populations rose more quickly in fields of Trapper than in Century or Triumph fields. The owners of all Trapper fields sampled initiated aerial application of insecticide for pea aphid control; at the time of spraying in 1985, plants in Trapper fields had significantly greater numbers of aphids in sweep samples than such samples from Century or Triumph fields. In 1986, Triumph plants supported greater numbers of aphids than Century or Trapper plants. Triumph plants remained green longer than plants of the other cultivais; in 1985 pea aphid numbers on this cultivar were highest on the last date sampled.Yield components were measured in sprayed and unsprayed plots within the commercial fields. When data were averaged for each cultivar, there were no significant differences in yield per area or in 1000 seed weight between sprayed and unsprayed plots. Data indicated that existing economic thresholds are too low for Trapper peas. However, one of the fields of Trapper peas that we sampled had significantly reduced numbers of pods per plant, yield per square metre, and weight of 1000 seeds in the unsprayed plot; this field had the largest population of pea aphids of any field sampled, with aphid numbers peaking at 48.5 ± 9.2 (SE) per plant lip during pod formation and filling. Significant yield losses also occurred in unsprayed plots of a Triumph field, which had a peak aphid population of 4.8 ± 1.6 per plant stem at pod maturation.
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Kordan, Bożena, Lesław Lahuta, Katarzyna Dancewicz, Wojciech Sądej i Beata Gabryś. "Effect of Lupin Cyclitols on Pea Aphid Probing Behaviour". Journal of Plant Protection Research 51, nr 2 (1.04.2011): 171–78. http://dx.doi.org/10.2478/v10045-011-0030-z.
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Effect of Lupin Cyclitols on Pea Aphid Probing BehaviourThe cyclitols: D-pinitol, D-chiro-inositol are naturally present in the tissues ofLupinus angustifolius. The effect of these cyclitols on the behaviour of the pea associated clone ofAcyrthosiphon pisumduring various stages of probing was studied. The main stage of probing studied was the stylet penetration in mesphyll and vascular bundle. D-pinitol, D-chiro-inositol and their mixture were exogenously applied to peaPisum sativumexplants and the aphid probing behaviour was evaluated using the Electrical Penetration Graph technique (EPG). Feeding of peas with cyclitols at a concentration of 10 mM, caused a selective accumulation of D-pinitol and D-chiro-inositol in stems, leaf petioles, and leaf blades. In aphid bodies, both cyclitols were traced, respectively, to the host plant treatment. The new cyclitols in pea tissues did not significantly affect the total duration and frequency of aphid activities during probing in peripheral as well as vascular tissues. However, the aphid behaviour on cyclitol-treated plants as compared to their behaviour on the control was slightly altered. Non-probing and probing in mesophyl prevailed among aphid activities during the initial period of stylet penetration. Aphids on D-pinitol+D-chiro-inositol-treated plants reached phloem vessels relatively later than aphids on the control and D-chiro-inositol plants. There were recurrent switches between E1 (salivation) and E2 (sap ingestion) patterns in some aphids during the phloem phase on D-pinitol and D-pinitol+D-chiro-inositol - treated plants. This may reflect difficulties in the uptake of the phloem sap, and point to lupin cyclitols as being responsible, at least in part, for the rejection ofL. angustifoliusas a host plant by the pea clone ofA. pisum.
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Li, Chunchun, Weining Yuan, Yuping Gou, Kexin Zhang, Qiangyan Zhang, Jing-Jiang Zhou i Changzhong Liu. "The Impact of Ultraviolet-B Radiation on the Sugar Contents and Protective Enzymes in Acyrthosiphon pisum". Insects 12, nr 12 (25.11.2021): 1053. http://dx.doi.org/10.3390/insects12121053.
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Natural and anthropogenic changes have been altering many environmental factors. These include the amount of solar radiation reaching the Earth’s surface. However, the effects of solar radiation on insect physiology have received little attention. As a pest for agriculture and horticulture, aphids are one of the most difficult pest groups to control due to their small size, high fecundity, and non-sexual reproduction. Study of the effects of UV-B radiation on aphid physiology may provide alternative control strategies in pest management. In this study, we examined the effects of UV-B radiation on protein and sugar contents, as well as the activities of protective enzymes, of the red and green morphs of the pea aphid over eight generations. The results indicated a significant interaction between UV-B radiation and aphid generations. Exposure of the pea aphids to UV-B radiation caused a significant decrease in the protein content and a significant increase in the glycogen and trehalose contents at each generation as measured in whole aphid bioassays. The enzyme activity of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) of the pea aphids changed significantly at each generation with UV-B treatments. The SOD activity increased over eight generations to the highest level at G7 generation. However, the enzyme activity of CAT first increased and then decreased with UV-B treatments, and POD mostly gradually decreased over the eight generations. Therefore, UV-B radiation is an environmental factor that could result in physiological changes of the pea aphid. Moreover, our study discovered that red and green aphids did not display a significant consistent difference in the response to the UV-B treatments. These results may prove useful in future studies especially for assessing their significance in the adaptation and management against UV-B radiation.
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Congdon, B. S., B. A. Coutts, M. Renton i R. A. C. Jones. "Pea seed-borne mosaic virus Pathosystem Drivers under Mediterranean-Type Climatic Conditions: Deductions from 23 Epidemic Scenarios". Plant Disease 101, nr 6 (czerwiec 2017): 929–40. http://dx.doi.org/10.1094/pdis-08-16-1203-re.
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Drivers of Pea seed-borne mosaic virus (PSbMV) epidemics in rainfed field pea crops were examined under autumn to spring growing conditions in a Mediterranean-type environment. To collect aphid occurrence and PSbMV epidemic data under a diverse range of conditions, 23 field pea data collection blocks were set up over a 6-year period (2010 to 2015) at five locations in the southwest Australian grain-growing region. PSbMV infection levels in seed sown (0.1 to 13%), time of sowing (22 May to 22 June), and cultivar (Kaspa or PBA Twilight) varied with location and year. Throughout each growing season, rainfall data were collected, leaf and seed samples were tested to monitor PSbMV incidence in the crop and transmission from harvested seed, and sticky traps were used to monitor flying aphid numbers. Winged migrant Acyrthosiphon kondoi, Lipaphis erysimi, Myzus persicae, and Rhopalosiphum padi were identified in green tile traps in 2014 and 2015. However, no aphid colonization of field pea plants ever occurred in the blocks. The deductions made from collection block data illustrated how the magnitude of PSbMV spread prior to flowering is determined by two primary epidemic drivers: (i) PSbMV infection incidence in the seed sown, which defines the magnitude of virus inoculum source for within-crop spread by aphids, and (ii) presowing rainfall that promotes background vegetation growth which, in turn, drives early-season aphid populations and the time of first arrival of their winged migrants to field pea crops. Likely secondary epidemic drivers included wind-mediated PSbMV plant-to-plant contact transmission and time of sowing. PSbMV incidence at flowering time strongly influenced transmission rate from harvested seed to seedlings. The data collected are well suited for development and validation of a forecasting model that informs a Decision Support System for PSbMV control in field pea crops.
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Stadler, B., i M. Mackauer. "INFLUENCE OF PLANT QUALITY ON INTERACTIONS BETWEEN THE APHID PARASITOID EPHEDRUS CALIFORNICUS BAKER (HYMENOPTERA: APHIDIIDAE) AND ITS HOST, ACYRTHOSIPHON PISUM (HARRIS) (HOMOPTERA: APHIDIDAE)". Canadian Entomologist 128, nr 1 (luty 1996): 27–39. http://dx.doi.org/10.4039/ent12827-1.
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AbstractWe determined variations in selected life-history parameters in a tritrophic system that consisted of a plant (broad bean, Vicia faba L.), an aphid (pea aphid, Acyrthosiphon pisum), and an aphid parasitoid (Ephedras californicus). We manipulated plant and aphid quality by growing bean plants in a high- and a low-quality nutrient solution for three generations. Pea aphids adapted to reduced nutrient availability by differentially allocating resources to somatic and gonadal growth across generations. On low-quality plants, time from birth to adult increased and dry mass decreased. The number of sclerotized embryos was correlated with adult dry mass. By contrast, in E. californicus, variations in dry mass, rate of development, and number of ovarial eggs did not suggest transgenerational adaptations to resource quality as measured by aphid size. The number of mature eggs was dependent on female age. Development time varied with parasitoid sex and was independent of aphid stage at the time of death. In the low-quality treatment, males survived on average longer than females eclosing from the same kinds of hosts.Aphids and their parasitoids have evolved flexible life-history strategies in response to variations in plant quality. Pea aphids adapted to qualitatively variable resources by optimizing the balance between somatic and gonadal investment across successive generations. But E. californicus responded to low host quality at the level of the individual, rather than across generations; the trade-off pattern was influenced by the host’s growth potential after parasitization.
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Wu, Qiong, Xiang Zhang, Xianghao Weng, Lingling Gao, Xuefei Chang, Xingxing Wang i Zhaozhi Lu. "Identification and Characterization of Resistance of Three Aphid Species on Contrasting Alfalfa Cultivars". Insects 13, nr 6 (9.06.2022): 530. http://dx.doi.org/10.3390/insects13060530.
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Aphids on alfalfa (Medicago sativa) including Aphis craccivora Koch (cowpea aphid, CPA), Acyrthosiphon pisum Harris (pea aphid, PA) and Therioaphis trifolii Buckton (spotted alfalfa aphid, SAA) cause significant yield losses worldwide. In this experiment, the development of these three species of aphids on 16 alfalfa cultivars was compared. The results showed that the plant cultivar had a significant influence on the development of aphids as there are significant differences in the body weight of aphids reared on different alfalfa cultivars. In addition, antibiosis between the alfalfa cultivars Pegasis and Gannong NO.9 and the three species of aphids was evaluated by measuring aphid body weight and fecundity. Antixenosis was measured using choice tests, and feeding behavior was quantified using electrical penetration graphs (EPG). The Pegasis cultivar was observed to have both antibiosis and antixenosis effects with CPA, but was susceptible to PA and SAA compared with the Gannong NO.9 cultivar. CPA had less mean body weight, less fecundity, and shorter feeding time on the Pegasis cultivar, and preferred to settle on Gannong NO.9 cultivar. In contrast, Gannong NO.9 exhibits antibiosis and antixenosis to PA and SAA compared with Pegasis, as shown by lower body weight, lower fecundity and chose to settle less often, but EPG data showed that PA and SAA showed no different significance in feeding behavior between Pegasis and Gannong NO.9.
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Wilkinson, T., D. Ashford, J. Pritchard i A. Douglas. "Honeydew sugars and osmoregulation in the pea aphid Acyrthosiphon pisum". Journal of Experimental Biology 200, nr 15 (1.01.1997): 2137–43. http://dx.doi.org/10.1242/jeb.200.15.2137.
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Pea aphids, Acyrthosiphon pisum, containing their symbiotic bacteria (untreated aphids) and experimentally deprived of their bacteria by treatment with the antibiotic rifampicin (antibiotic-treated aphids) were reared on the plant Vicia faba. The sugars in the honeydew produced by untreated aphids comprised predominantly the monosaccharides glucose and fructose, while the honeydew of antibiotic-treated aphids contained considerable amounts of oligosaccharides of up to 16 hexose units. The honeydew and haemolymph of the aphids were iso-osmotic, and their osmotic pressure was significantly lower in untreated aphids (0.91­0.95 MPa) than in antibiotic-treated aphids (1.01­1.05 MPa) (P<0.05). For insects reared on chemically defined diets containing 0.15­1.0 mol l-1 sucrose (osmotic pressure 1.1­4.0 MPa), the osmotic pressure of the aphid haemolymph did not vary with dietary osmotic pressure, but was regulated to approximately 1.0 MPa in untreated and 1.3 MPa in antibiotic-treated aphids. The sugars in the aphid honeydew varied with dietary sucrose concentration; with monosaccharides dominant at low concentrations and oligosaccharides dominant at high concentrations of dietary sucrose. The lowest dietary sucrose concentration at which honeydew oligosaccharides were detected was 0.2 mol l-1 for the antibiotic-treated aphids and 0.3 mol l-1 for untreated aphids. These data indicate that the aphid, and not its associated microbiota, mediates the synthesis of oligosaccharides when the osmotic pressure of the ingesta is high.
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Lu, Hong, Junjie Zhu, Jinting Yu, Xiaofang Chen, Le Kang i Feng Cui. "A Symbiotic Virus Facilitates Aphid Adaptation to Host Plants by Suppressing Jasmonic Acid Responses". Molecular Plant-Microbe Interactions® 33, nr 1 (styczeń 2020): 55–65. http://dx.doi.org/10.1094/mpmi-01-19-0016-r.
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Symbiotic viruses exist in many insects; however, their functions in host insects are not well understood. In this study, we explored the role of acyrthosiphon pisum virus (APV) in the interaction of its host aphid Acyrthosiphon pisum with plants. APV is primarily located in aphid salivary glands and gut and propagated in the insect. APV is horizontally transmitted to host plants during aphid feeding, but the virus does not replicate in the host plant. When the pea host race of aphids colonized two low-fitness plants, Medicago truncatula and Vicia villosa, the virus titers in both the aphids and plants significantly increased. Furthermore, APV infection strongly promoted the survival rate of the pea host race on V. villosa. Transcriptomic analysis showed that only 0.85% of aphid genes responded to APV infection when aphids fed on V. villosa, with a fold change in transcript levels of no more than fourfold. The improved survival due to APV infection was apparently related to the inhibitory effect of the virus on levels of phytohormone jasmonic acid (JA) and JA-isoleucine. Our data suggest a benefit of the symbiotic virus to its aphid host and demonstrate a novel case of symbiotic virus-mediated three-species interaction.
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Stewart, Sophie Alice, Simon Hodge, Nurul Ismail, John W. Mansfield, Bart J. Feys, Jean-Marie Prospéri, Thierry Huguet, Cécile Ben, Laurent Gentzbittel i Glen Powell. "The RAP1 Gene Confers Effective, Race-Specific Resistance to the Pea Aphid in Medicago truncatula Independent of the Hypersensitive Reaction". Molecular Plant-Microbe Interactions® 22, nr 12 (grudzień 2009): 1645–55. http://dx.doi.org/10.1094/mpmi-22-12-1645.
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Plant resistance to pathogens is commonly associated with a hypersensitive response (HR), but the degree to which the HR is responsible for incompatibility is subject to debate. Resistance to aphids is likely to share features with resistance to pathogens but is less well understood. Here, we report effective resistance to the pea aphid Acyrthosiphon pisum in Medicago truncatula. Aphids lost weight and died rapidly (within two days) on the resistant genotype Jemalong, which developed necrotic lesions following infestation. Lesions were induced by nonvascular intracellular stylet punctures by aphids, remained localized to the site of stylet entry, stained for the presence of reactive oxygen species, and were similar to the HR induced by the bacterial pathogen Pseudomonas syringae pv. phaseolicola. The implication that aphid-induced lesions confer resistance was tested by quantitative trait loci analysis using recombinant inbred lines derived from a cross between Jemalong and the susceptible genotype DZA315.16. One major locus, RAP1, was identified that was sufficient to confer race-specific resistance against the pea aphid and was mapped to the middle of chromosome 3. Surprisingly, a separate locus, mapping to the top of chromosome 3, governed aphid-induced HR, indicating that the HR-like lesions are not required for RAP1-mediated aphid resistance.
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Seidenglanz, M., I. Huňady, J. Poslušná i A. K. Løes. "Influence of intercropping with spring cereals on the occurrence of pea aphids (Acyrthosiphon pisum Harris, 1776) and their natural enemies in field pea (Pisum sativum L.)". Plant Protection Science 47, No. 1 (1.03.2011): 25–36. http://dx.doi.org/10.17221/40/2010-pps.
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Occurrences of pea aphids and their natural enemies (syrphids, mummies caused by entomopathogenic fungi Beauveria sp. and by the parasitic wasp Aphidius ervi) were compared in monocultures and mixtures of field peas and spring cereals in three seasons (2008–2010). At the beginning of colonisation, the occurrence of aphids was not substantially influenced by intercropping with cereals. However, the numbers of pea aphids located on inflorescences started to decline earlier in mixtures compared with monoculture. More syrphids (eggs + larvae) were found in mixtures than in monoculture, and more syrphid eggs were found in young aphid colonies (10 to 20 individuals) in mixtures. Intercropping did not influence the occurrence of fungal mummies (Beauveria sp.), but mixtures tended to have more aphid colonies infested by A. ervi in 2008 and 2009.
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Gospodarek, Janina, Agnieszka Klimek-Kopyra i Milena Rusin. "Suitability of NDVI index to pea condition evaluation at diverse phosphorus fertilization". Italian Journal of Agronomy 15, nr 1 (2.03.2020): 35–47. http://dx.doi.org/10.4081/ija.2020.1418.
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In this 3-year study the suitability of the normalized differenced vegetation index (NDVI) to the evaluation of pea plant infestation by aphids and expected seeds yield was investigated. The effect was assessed in the conditions of the increasing doses of phosphorus fertilization (0, 70, and 140 kg P2O5 ha–1) and in the different pea aphid (Acyrthosiphon pisum Harris) occurrence on six various cultivars of pea. Independent of the dose, the phosphorus fertilization supported the occurrence of aphids on pea plants of Batuta, Model, and Protecta cultivars where in Tarchalska and Mecenas cultivars only the standard dose (70 kg ha–1) showed such effect. NDVI index was not clearly, unambiguously correlated to the intensity of A. pisum occurrence. Such factors as the deficiency or excessive amount of phosphorus, as well as meteorological conditions and the cultivar of host plant had the greater effect on its value than the presence of aphids. All this testifies that the NDVI index is not reliable indicator of aphid occurrence on pea, however it can offer a promising method to select the cultivars under sub-opitmal conditions. The seed yield was strongly related to agronomical factors (fertilization, cultivars) and plant (NDVI) variable, while marginally to environmental variable (aphids).
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Yadav, Vandana, i Sunita Arya. "EFFECT OF GUARD CROPS ON POPULATION DENSITY OF PEA APHID (ACYRTHOSIPHON PISUM HARRIS) AGAINST PEA (PISUM SATIVUM L.)". International Journal of Biological Innovations 04, nr 01 (2022): 221–26. http://dx.doi.org/10.46505/ijbi.2022.4124.
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A field trial was conducted during two rabi cropping seasons 2017-18 and 2018-19 to evaluate the role of some field crops as guard plants in pea crop. Sorghum, bajra and maize were cultivated at the boundaries of target crop (pea crop) to explore their ability to attract pea aphids (Acyrthosiphon pisum Harris) away from pea crop. The outcome of the study revealed that sowing of maize at the boundaries of pea fields was not much effective in reducing the aphid infestation. On the other hand, fields surrounded by sorghum showed most effective protection from pea aphids attack on pea crop followed by bajra and polyculture (sorghum, bajra and maize with pea crop).
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Quisenberry, S. S., D. J. Schotzko, P. F. Lamb i F. L. Young. "Insect Distribution in a Spring Pea-Winter Wheat-Spring Barley Crop Rotation System". Journal of Entomological Science 35, nr 3 (1.07.2000): 327–33. http://dx.doi.org/10.18474/0749-8004-35.3.327.
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The effects of tillage method (conventional or conservative) and weed management level (recommended or minimum) on insect distribution in a wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), and pea (Pisum sativum L.) rotation were studied. Aphids were the major insect species on winter wheat and spring barley, but were not of economic importance. Beneficial species impacted aphid population levels by maintaining their numbers below economic thresholds. Tillage method and weed management level had limited impact on aphid and beneficial insect populations. Pea leaf weevil (Sitonia lineatus [L.]) and pea weevil (Bruchus pisorum [L.]) populations reached economic injury levels in 1992; two insecticide applications were needed. Pea leaf weevil populations did not reach economic levels in 1993; however, pea weevil populations reached an economic level at flowering stage and an insecticide was applied. Pea leaf weevil populations were higher in conventional tillage plots compared with conservation tillage plots. Early-season insecticide applications suppressed beneficial insects in the pea plots.
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Serteyn, Laurent, Céleste Quaghebeur, Marc Ongena, Nuri Cabrera, Andrea Barrera, Marco A. Molina-Montenegro, Frédéric Francis i Claudio C. Ramírez. "Induced Systemic Resistance by a Plant Growth-Promoting Rhizobacterium Impacts Development and Feeding Behavior of Aphids". Insects 11, nr 4 (8.04.2020): 234. http://dx.doi.org/10.3390/insects11040234.
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The effects of microorganisms on plant-insect interactions have usually been underestimated. While plant growth-promoting rhizobacteria (PGPR) are known to induce plant defenses, endosymbiotic bacteria hosted by herbivorous insects are often beneficial to the host. Here, we aimed to assess whether PGPR-induced defenses in broad bean plants impact the pea aphid, depending on its genotype and the presence of endosymbionts. We estimated aphid reproduction, quantified defense- and growth-related phytohormones by GC-MS, and measured different plant growth and physiology parameters, after PGPR treatment. In addition, we recorded the feeding behavior of aphids by electropenetrography. We found that the PGPR treatment of broad bean plants reduced the reproduction of one of the pea aphid clones. We highlighted a phenomenon of PGPR-induced plant defense priming, but no noticeable plant growth promotion. The main changes in aphid probing behavior were related to salivation events into phloem sieve elements. We suggest that the endosymbiont Hamiltonella defensa played a key role in plant-insect interactions, possibly helping aphids to counteract plant-induced resistance and allowing them to develop normally on PGPR-treated plants. Our results imply that plant- and aphid-associated microorganisms add greater complexity to the outcomes of aphid-plant interactions.
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Febvay, G., Y. Rahbe, M. Rynkiewicz, J. Guillaud i G. Bonnot. "Fate of dietary sucrose and neosynthesis of amino acids in the pea aphid, acyrthosiphon pisum, reared on different diets". Journal of Experimental Biology 202, nr 19 (1.10.1999): 2639–52. http://dx.doi.org/10.1242/jeb.202.19.2639.
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The fate of sucrose, the major nutrient of an aphid's natural food, was explored by radiolabeling in the pea aphid Acyrthosiphon pisum. To investigate the influence of nitrogen quality of food on amino acid neosynthesis, pea aphids were reared on two artificial diets differing in their amino acid composition. The first (diet A) had an equilibrated amino acid balance, similar to that derived from analysis of aphid carcass, and the other (diet B) had an unbalanced amino acid composition similar to that of legume phloem sap. Aphids grown on either diet expired the same quantity of sucrose carbon as CO(2), amounting to 25–30 % of the ingested sucrose catabolized in oxidation pathways. On diet A, the aphids excreted through honeydew about twice as much sucrose carbon as on diet B (amounting to 12.6 % of the ingested sucrose for diet A and 8.4 % for diet B), while amounts of sucrose carbons incorporated into exuviae were almost identical (1.9 % of the ingested sucrose on diet A and 2.7 % on diet B). There was also no difference in the amounts of sucrose carbon incorporated into the aphid tissues, which represented close to 50 % of the ingested sucrose. Sucrose carbons in the aphid tissues were mainly incorporated into lipids and the quantities involved were the same in aphids reared on either diet. On diet B, we observed neosynthesis of all protein amino acids from sucrose carbons and, for the first time in an aphid, we directly demonstrated the synthesis of the essential amino acids leucine, valine and phenylalanine. Amino acid neosynthesis from sucrose was significantly higher on diet B (11.5 % of ingested sucrose carbons) than on diet A (5.4 %). On diet A, neosynthesis of most of the amino acids was significantly diminished, and synthesis of two of them (histidine and arginine) was completely suppressed. The origin of amino acids egested through honeydew was determined from the specific activity of the free amino acid pool in the aphid. Aphids are able to adjust to variation in dietary amino acids by independent egestion of each amino acid. While more than 80 % of excreted nitrogen was from food amino acids, different amino acids were excreted in honeydew of aphids reared on the two diets. The conversion yields of dietary sucrose into aphid amino acids determined in this study were combined with those obtained previously by studying the fate of amino acids in pea aphids reared on diet A. The origin of all the amino acid carbons in aphid tissues was thus computed, and the metabolic abilities of aphid are discussed from an adaptive point of view, with respect to their symbiotic status.
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Smith, Michael T., i Ray F. Severson. "Host Recognition by the Blackmargined Aphid (Homoptera: Aphididae) on Pecan". Journal of Entomological Science 27, nr 2 (1.04.1992): 93–112. http://dx.doi.org/10.18474/0749-8004-27.2.93.
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Leaf discs from pecan, Carya illinoensis (Wangenh.) K. Koch, pea, Pisum sativum L., peach, Prunus persica (L.) Batsch, and fig, Fiscus benjamina L. were presented to nymph and adult blackmargined aphids, Monellia caryella (Fitch) in no-choice and choice bioassays. Nymph longevity and developmental rates, and adult longevity and reproductive rates were significantly greater when aphids were placed on pecan than on pea, peach or fig. In no-choice bioassays, both nymph and adult aphids preferred to settle-on pecan, while they preferred to wander- or settle-off of pea, peach and fig. In choice bioassays, both nymph and adult aphids preferred to settle-on pecan than to settle-on pea, peach and fig. Analysis of pecan, pea, peach and fig leaf cuticular chemistry showed that n-alkane distribution patterns and the major cuticular components, specifically triterpenes and their oxidation products, differed among the four plant species. This study provides the first evidence within the pecan/aphid interactive system which suggests that the distinct foliar cuticular chemistry of pecan may have an influence on the host recognition behavior of M. caryella.
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Chauhan, J. V., Bindu K. Panickar, A. R. Prajapati i J. B. Delvadiya. "Screening of pea germplasms against insect pests". EMERGENT LIFE SCIENCES RESEARCH 09, nr 02 (2023): 221–33. http://dx.doi.org/10.31783/elsr.2023.92221233.
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A field experiment was conducted to screen fifteen germplasms of peas against different insect pests at Pulses Research Station, Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar, Gujarat during rabi 2019-20 and 2020-21. The germplasm HFP 1502 recorded significantly minimum aphid (Aphis craccivora Koch) (3.78 aphids/10 cm shoot) whereas, the germplasm Pant P 476 recorded significantly lowest leafhopper (Empoasca kerri Pruthi) population (1.96 leafhoppers/3 leaves). Out of fifteen field pea germplasm significantly lowest whitefly (Bemisia tabaci Gennadius) population (0.94 whitefly/3 leaves) was noticed on the IPFD 10-12. The Helicoverpa armigera Hubner larval population indicated a significant minimum (0.39 larva/plant) on germplasm Pant P 418 and also recorded significantly lower (3.24%) pod damage. The significantly highest seed yield (937 kg/ha) was recorded on Pant P 476 followed by genotypes IPFD 10-12, Prakash, and IPF 18-14.
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Zhang, Xiang, Qiong Wu, Jianing Mu, Zunqi Chao, Qi He, Ting Gao, Chuan Wang, Mark R. McNeill i Zhaozhi Lu. "The Efficacy of Biological Control for the Suppression of the Pea Aphid (Acyrthosiphon Pisum): Does the Resistance of Alfalfa Cultivars Matter?" Insects 14, nr 1 (27.12.2022): 28. http://dx.doi.org/10.3390/insects14010028.
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The pea aphid, Acyrthosiphon pisum Harris, is a major pest of alfalfa in northwestern China. However, the roles of different groups of natural enemies in combination with aphid-resistant cultivars in the suppression of the pea aphid have not been clarified under field conditions. In this study, we used experimental cages to better understand the top-down (natural enemies) and bottom-up (nine alfalfa cultivars) biological processes, as well as the individual roles of the two processes, in the control of the pea aphid. There was a significant difference in resistance among cultivar classes revealed when natural enemies were excluded. The functional contribution of top-down suppression was higher than the bottom-up process, with natural enemies significantly suppressing aphid populations, regardless of the resistance level of different alfalfa cultivars. The mean biological efficacies of predators, parasitoids, and mixed populations of natural enemies were 85%, 42%, and 88%, respectively. Overall, our study indicated that natural enemies play a critical role in suppressing aphid populations, especially in the summer, whereas cultivar resistance did not combine effectively with natural enemies to inhibit the growth of aphids. Conservation biological control (CBC) can be implemented in the alfalfa production regions in northwestern China to reduce the overreliance on insecticides for the control of pests and mitigate their harmful effects on humans, ecosystems, and biodiversity.
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Pandharikar, Gaurav, Jean-Luc Gatti, Jean-Christophe Simon, Pierre Frendo i Marylène Poirié. "Aphid infestation differently affects the defences of nitrate-fed and nitrogen-fixing Medicago truncatula and alters symbiotic nitrogen fixation". Proceedings of the Royal Society B: Biological Sciences 287, nr 1934 (2.09.2020): 20201493. http://dx.doi.org/10.1098/rspb.2020.1493.
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Legumes can meet their nitrogen requirements through root nodule symbiosis, which could also trigger plant systemic resistance against pests. The pea aphid Acyrthosiphon pisum , a legume pest, can harbour different facultative symbionts (FS) influencing various traits of their hosts. It is therefore worth determining if and how the symbionts of the plant and the aphid modulate their interaction. We used different pea aphid lines without FS or with a single one ( Hamiltonella defensa , Regiella insecticola, Serratia symbiotica ) to infest Medicago truncatula plants inoculated with Sinorhizobium meliloti (symbiotic nitrogen fixation, SNF) or supplemented with nitrate (non-inoculated, NI). The growth of SNF and NI plants was reduced by aphid infestation, while aphid weight (but not survival) was lowered on SNF compared to NI plants. Aphids strongly affected the plant nitrogen fixation depending on their symbiotic status, suggesting indirect relationships between aphid- and plant-associated microbes. Finally, all aphid lines triggered expression of Pathogenesis-Related Protein 1 ( PR1 ) and Proteinase Inhibitor (PI) , respective markers for salicylic and jasmonic pathways, in SNF plants, compared to only PR1 in NI plants. We demonstrate that the plant symbiotic status influences plant–aphid interactions while that of the aphid can modulate the amplitude of the plant's defence response.
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Podjasek, Joshua O., Lisa M. Bosnjak, Daniel J. Brooker i Edward B. Mondor. "Alarm pheromone induces a transgenerational wing polyphenism in the pea aphid, Acyrthosiphon pisum". Canadian Journal of Zoology 83, nr 8 (1.08.2005): 1138–41. http://dx.doi.org/10.1139/z05-108.
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In response to increased predation risk, many organisms exhibit transgenerational polyphenisms whereby offspring have behavioural and (or) morphological adaptations to avoid natural enemies. The mechanisms underlying altered phenotypic expression, however, are not well understood. Aphids commonly exhibit a transgenerational wing-induction polyphenism in response to predators and parasitoids, but the stimuli inducing winged offspring production have not yet been identified. As aphids commonly emit the alarm pheromone (E)-β-farnesene (EBF) when physically attacked, this compound is a reliable signal of increased predation risk for asexual conspecifics. Here we show that maternal detection of EBF induces a transgenerational wing polyphenism in offspring of the pea aphid, Acyrthosiphon pisum (Harris, 1776). In response to 50, 500, or 5000 ng of EBF vapor, aphids responded with 2.5-, 5.0-, and 6.0-fold increases in winged offspring production, respectively. Thus, alarm pheromone may alter aphid transgenerational phenotypic expression, thereby influencing aphid – natural enemy dynamics.
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Flinn, P. W., A. A. Hower i R. A. J. Taylor. "PREFERENCE OF REDUVIOLUS AMERICOFERUS (HEMIPTERA: NABIDAE) FOR POTATO LEAFHOPPER NYMPHS AND PEA APHIDS". Canadian Entomologist 117, nr 12 (grudzień 1985): 1503–8. http://dx.doi.org/10.4039/ent1171503-12.
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AbstractThe preference of the nabid, Reduviolus americoferus (L.), for potato leafhopper nymphs, Empoasca fabae (Harris), and pea aphids, Acyrthosiphon pisum (Harris), was examined using functional response models. The nabid exhibited a type-II functional response to each prey. Handling time was much higher for the aphid than for the leafhopper (3.623 vs. 0.211 h). Instantaneous search rates were also higher for the aphid (0.096 vs. 0.020 h−1). A preference index was calculated using the ratio of the instantaneous search rates. The nabid exhibited strong preference for the aphid; when both prey were present in equal numbers, the nabid consumed 3 times as many aphids. The predator did not switch to leafhopper nymphs as the proportion of leafhoppers was increased.
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Loth, Karine, Nicolas Parisot, Françoise Paquet, Hugo Terrasson, Catherine Sivignon, Isabelle Rahioui, Mélanie Ribeiro Lopes i in. "Aphid BCR4 Structure and Activity Uncover a New Defensin Peptide Superfamily". International Journal of Molecular Sciences 23, nr 20 (18.10.2022): 12480. http://dx.doi.org/10.3390/ijms232012480.
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Aphids (Hemiptera: Aphidoidea) are among the most detrimental insects for agricultural plants, and their management is a great challenge in agronomical research. A new class of proteins, called Bacteriocyte-specific Cysteine-Rich (BCR) peptides, provides an alternative to chemical insecticides for pest control. BCRs were initially identified in the pea aphid Acyrthosiphon pisum. They are small disulfide bond-rich proteins expressed exclusively in aphid bacteriocytes, the insect cells that host intracellular symbiotic bacteria. Here, we show that one of the A. pisum BCRs, BCR4, displays prominent insecticidal activity against the pea aphid, impairing insect survival and nymphal growth, providing evidence for its potential use as a new biopesticide. Our comparative genomics and phylogenetic analyses indicate that BCRs are restricted to the aphid lineage. The 3D structure of BCR4 reveals that this peptide belongs to an as-yet-unknown structural class of peptides and defines a new superfamily of defensins.
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Ballesteros, Gabriel I., Jürgen Gadau, Fabrice Legeai, Angelica Gonzalez-Gonzalez, Blas Lavandero, Jean-Christophe Simon i Christian C. Figueroa. "Expression differences in Aphidius ervi (Hymenoptera: Braconidae) females reared on different aphid host species". PeerJ 5 (21.08.2017): e3640. http://dx.doi.org/10.7717/peerj.3640.
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The molecular mechanisms that allow generalist parasitoids to exploit many, often very distinct hosts are practically unknown. The wasp Aphidius ervi, a generalist koinobiont parasitoid of aphids, was introduced from Europe into Chile in the late 1970s to control agriculturally important aphid species. A recent study showed significant differences in host preference and host acceptance (infectivity) depending on the host A. ervi were reared on. In contrast, no genetic differentiation between A. ervi populations parasitizing different aphid species and aphids of the same species reared on different host plants was found in Chile. Additionally, the same study did not find any fitness effects in A. ervi if offspring were reared on a different host as their mothers. Here, we determined the effect of aphid host species (Sitobion avenae versus Acyrthosiphon pisum reared on two different host plants alfalfa and pea) on the transcriptome of adult A. ervi females. We found a large number of differentially expressed genes (between host species: head: 2,765; body: 1,216; within the same aphid host species reared on different host plants: alfalfa versus pea: head 593; body 222). As expected, the transcriptomes from parasitoids reared on the same host species (pea aphid) but originating from different host plants (pea versus alfalfa) were more similar to each other than the transcriptomes of parasitoids reared on a different aphid host and host plant (head: 648 and 1,524 transcripts; body: 566 and 428 transcripts). We found several differentially expressed odorant binding proteins and olfactory receptor proteins in particular, when we compared parasitoids from different host species. Additionally, we found differentially expressed genes involved in neuronal growth and development as well as signaling pathways. These results point towards a significant rewiring of the transcriptome of A. ervi depending on aphid-plant complex where parasitoids develop, even if different biotypes of a certain aphid host species (A. pisum) are reared on the same host plant. This difference seems to persist even after the different wasp populations were reared on the same aphid host in the laboratory for more than 50 generations. This indicates that either the imprinting process is very persistent or there is enough genetic/allelic variation between A. ervi populations. The role of distinct molecular mechanisms is discussed in terms of the formation of host fidelity.
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Linz, Lucas B., Sijun Liu, Nanasaheb P. Chougule i Bryony C. Bonning. "In VitroEvidence Supports Membrane Alanyl Aminopeptidase N as a Receptor for a Plant Virus in the Pea Aphid Vector". Journal of Virology 89, nr 22 (26.08.2015): 11203–12. http://dx.doi.org/10.1128/jvi.01479-15.
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ABSTRACTInsect-borne plant viruses cause significant agricultural losses and jeopardize sustainable global food production. Although blocking plant virus transmission would allow for crop protection, virus receptors in insect vectors are unknown. Here we identify membrane alanyl aminopeptidase N (APN) as a receptor for pea enation mosaic virus (PEMV) coat protein (CP) in the gut of the pea aphid,Acyrthosiphon pisum, using a far-Western blot method. Pulldown and immunofluorescence binding assays and surface plasmon resonance were used to confirm and characterize CP-APN interaction. PEMV virions and a peptide comprised of PEMV CP fused to a proline-rich hinge (-P-) and green fluorescent protein (CP-P-GFP) specifically bound to APN. Recombinant APN expressed in Sf9 cells resulted in internalization of CP-P-GFP, which was visualized by confocal microscopy; such internalization is an expected hallmark of a functional gut receptor. Finally, in assays with aphid gut-derived brush border membrane vesicles, binding of CP-P-GFP competed with binding of GBP3.1, a peptide previously demonstrated to bind to APN in the aphid gut and to impede PEMV uptake into the hemocoel; this finding supports the hypothesis that GBP3.1 and PEMV bind to and compete for the same APN receptor. Thesein vitrodata combined with previously publishedin vivoexperiments (S. Liu, S. Sivakumar, W. O. Sparks, W. A. Miller, and B. C. Bonning, Virology 401:107–116, 2010,http://dx.doi.org/10.1016/j.virol.2010.02.009) support the identification of APN as the first receptor in a plant virus vector. Knowledge of this receptor will provide for technologies based on PEMV-APN interaction designed to block plant virus transmission and to suppress aphid populations.IMPORTANCEA significant proportion of global food production is lost to insect pests. Aphids, in addition to weakening plants by feeding on their sap, are responsible for transmitting about half of the plant viruses vectored by insects. Growers rely heavily on the application of chemical insecticides to manage both aphids and aphid-vectored plant viral disease. To increase our understanding of plant virus-aphid vector interaction, we providein vitroevidence supporting earlierin vivowork for identification of a receptor protein in the aphid gut called aminopeptidase N, which is responsible for entry of the plant virus pea enation mosaic virus into the pea aphid vector. Enrichment of proteins found on the surface of the aphid gut epithelium resulted in identification of this first aphid gut receptor for a plant virus. This discovery is particularly important since the disruption of plant virus binding to such a receptor may enable the development of a nonchemical strategy for controlling aphid-vectored plant viruses to maximize food production.
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Kouamé, K. L., i M. Mackauer. "INFLUENCE OF STARVATION ON DEVELOPMENT AND REPRODUCTION IN APTEROUS VIRGINOPARAE OF THE PEA APHID, ACYRTHOSIPHON PISUM (HARRIS) (HOMOPTERA: APHIDIDAE)". Canadian Entomologist 124, nr 1 (luty 1992): 87–95. http://dx.doi.org/10.4039/ent12487-1.
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AbstractThe influence of nutrient stress on growth, development, and reproduction in apterous virginoparae of the pea aphid, Acyrthosiphon pisum (Harris), was investigated in the laboratory. We tested the hypothesis that species with a high reproductive investment have low resistance to starvation. Aphids in two groups were starved daily from birth for 4 h and 6 h, respectively, and compared with feeding counterparts reared on leaves of broad beans, Vicia faba L. Aphid wet weight increased as an exponential function of age in all groups. Starved aphids had lower adult weight and required longer from birth to parturition than feeding aphids. These effects increased with the length of daily starvation. The number of offspring produced was correlated with adult dry weight. Aphids were unable to compensate, or to compensate completely, for water and nutrient loss resulting from starvation. It is suggested that pea aphids allocate resources first to maintenance and then to reproduction when deprived of food.