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Nicolas Desneux - One of the best experts on this subject based on the ideXlab platform.
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sublethal effects of beta cypermethrin modulate interspecific interactions between specialist and generalist Aphid species on soybean
Ecotoxicology and Environmental Safety, 2020Co-Authors: Farman Ullah, Dunlun Song, Chen Luo, Lucie S Monticelli, Anneviolette Lavoir, Xiwu Gao, Nicolas DesneuxAbstract:Abstract In agroecosystems, plant-pest interactions are at the basis of complex food webs, which can be affected by both biotic and abiotic factors. In the present study, we evaluated the impact of the insecticide beta-cypermethrin on interspecific interactions between the specialist Aphid Aphis glycines and the generalist Aphid Aulacorthum solani on soybean. Aphis glycines showed higher fecundity than A. solani on soybean and the Aphids caused unbalanced reduction in population growth on each other. A sublethal concentration of beta-cypermethrin (LC5 for A. glycines) stimulated the reproduction of A. glycines but it did not impact the fecundity of A. solani. However, the LC5 of beta-cypermethrin enhanced the interspecific inhibition of fecundity between the two Aphid species. Moreover, the two species showed different spatial distribution on soybean seedlings. Aphis glycines mainly aggregated on the stem of soybean plant while A. solani colonized soybean leaves. The LC5 of beta-cypermethrin drove A. solani migrating from soybean leaves to stems independently of interspecific competition. Aphis glycines facilitated A. solani colonization on soybean plant through impacting host susceptibility, and vice versa. Nevertheless, such facilitated colonization-induced susceptibility could be modulated through exposure to the LC5 of beta-cypermethrin. These findings hinted that the pyrethroid insecticide beta-cypermethrin has the potential to mediate the interspecific competition between specialist and generalist Aphids (at the sublethal concentration of LC5), and that it could influence Aphid population growth and community structure in soybean crops. This knowledge could contribute to rationalize application of insecticides and to optimize Integrated Pest Management in soybean.
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worldwide populations of the Aphid aphis craccivora are infected with diverse facultative bacterial symbionts
Microbial Ecology, 2014Co-Authors: Cristina M Brady, Jason A. Wulff, Mark K Asplen, Keith R. Hopper, Catherine R. Linnen, Kerry M Oliver, Nicolas Desneux, George E. Heimpel, Jennifer A WhiteAbstract:Facultative bacterial endosymbionts can play an important role in the evolutionary trajectory of their hosts. Aphids (Hemiptera: Aphididae) are infected with a wide variety of facultative endosymbionts that can confer ecologically relevant traits, which in turn may drive microevolutionary processes in a dynamic selective environment. However, relatively little is known about how symbiont diversity is structured in most Aphid species. Here, we investigate facultative symbiont species richness and prevalence among worldwide populations of the cowpea Aphid, Aphis craccivora Koch. We surveyed 44 populations of A. craccivora, and detected 11 strains of facultative symbiotic bacteria, representing six genera. There were two significant associations between facultative symbiont and Aphid food plant: the symbiont Arsenophonus was found at high prevalence in A. craccivora populations collected from Robinia sp. (locust), whereas the symbiont Hamiltonella was almost exclusively found in A. craccivora populations from Medicago sativa (alfalfa). Aphids collected from these two food plants also had divergent mitochondrial haplotypes, potentially indicating the formation of specialized Aphid lineages associated with food plant (host-associated differentiation). The role of facultative symbionts in this process remains to be determined. Overall, observed facultative symbiont prevalence in A. craccivora was lower than that of some other well-studied Aphids (e.g., Aphis fabae and Acyrthosiphon pisum), possibly as a consequence of A. craccivora's almost purely parthenogenetic life history. Finally, most (70 %) of the surveyed populations were polymorphic for facultative symbiont infection, indicating that even when symbiont prevalence is relatively low, symbiont-associated phenotypic variation may allow population-level evolutionary responses to local selection.
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Multifaceted determinants of host specificity in an Aphid parasitoid
Oecologia, 2009Co-Authors: Nicolas Desneux, Keith R. Hopper, Ruth J. Barta, Kim A. Hoelmer, George E. HeimpelAbstract:The host specificity of insect parasitoids and herbivores is thought to be shaped by a suite of traits that mediate host acceptance and host suitability. We conducted laboratory experiments to identify mechanisms shaping the host specificity of the Aphid parasitoid Binodoxys communis . Twenty species of Aphids were exposed to B. communis females in microcosms, and detailed observations and rearing studies of 15 of these species were done to determine whether patterns of host use resulted from variation in factors such as host acceptance or variation in host suitability. Six species of Aphids exposed to B. communis showed no signs of parasitism. Four of these species were not recognized as hosts and two effectively defended themselves from attack by B. communis . Other Aphid species into which parasitoids laid eggs had low suitability as hosts. Parasitoid mortality occurred in the egg or early larval stages for some of these hosts but for others it occurred in late larval stages. Two hypotheses explaining low suitability were investigated in separate experiments: the presence of endosymbiotic bacteria conferring resistance to parasitoids, and Aphids feeding on toxic plants. An association between resistance and endosymbiont infection was found in one species ( Aphis craccivora ) , and evidence for the toxic plant hypothesis was found for the milkweed Aphids Aphis asclepiadis and Aphis nerii . This research highlights the multifaceted nature of factors determining host specificity in parasitoids.
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Potential of an alternative prey to disrupt predation of the generalist predator, Orius insidiosus, on the pest Aphid, Aphis glycines, via short-term indirect interactions
Bulletin of Entomological Research, 2008Co-Authors: Nicolas Desneux, R.j. O'neilAbstract:Generalist insect predators can significantly impact the dynamics of pest populations; and, using alternative prey, they can rapidly establish in disturbed agroecosystems. However, indirect interactions between prey can occur, leading to either increased or decreased predation on focal prey. The present paper demonstrates how alternative prey can disrupt predation by the hemipteran Orius insidiosus on the soybean Aphid Aphis glycines via short-term indirect interactions. We used laboratory microcosms to measure the impact of the predator on the population growth of the Aphid in the presence of alternative prey, soybean thrips Neohydatothrips variabilis, and we characterized the foraging behaviour of the predator to assess prey preference. We showed that O. insidiosus predation on Aphids was reduced in the presence of thrips and that this positive impact on Aphids increased as thrips density increased. Results from the behavioural experiment support the hypothesis of a prey preference toward thrips. When prey-pest ratio is Aphid-biased, short-term apparent commensalism between prey occurs in favour of the most abundant prey (Aphids) with no switching behaviour appearing in O. insidiosus. These results demonstrate that potential indirect interactions should be taken into account when considering O. insidiosus as a biocontrol agent against the soybean Aphid.
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suppression of population growth of the soybean Aphid aphis glycines matsumura by predators the identification of a key predator and the effects of prey dispersion predator abundance and temperature
Environmental Entomology, 2006Co-Authors: Nicolas Desneux, Robert J OneilAbstract:The soybean Aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), has recently invaded North America from Asia and has become a major pest in soybean. Using field surveys and cage exclusion techniques, we identified the effect of natural enemies and abiotic factors on the growth of soybean Aphid populations in 2004 and 2005. The soybean Aphid population was significantly limited by natural enemies in the field. Generalist predators dominated the natural enemy community. One species, Orius insidiosus Say (Hemiptera: Anthocoridae) represented 85–90% of predators found. There was a significant negative relationship between Aphid population growth and O. insidiosus abundance. For other predators, there were no relationships between abundance and Aphid population growth. The spatial distribution of Aphids among plants affected the impact of O. insidiosus on Aphid population growth. When Aphids were distributed in a clumped manner, increases in O. insidiosus numbers resulted in lower Aphid growth rates. For randomly distributed Aphids, there was no effect of O. insidiosus abundance on Aphid population growth. Finally, we found no relationship between Aphid population growth and degree-day accumulations. The potential of O. insidiosus to suppress soybean Aphid population growth at low Aphid numbers and the importance of the predator to soybean Aphid integrated pest management are discussed.
Christoph Vorburger - One of the best experts on this subject based on the ideXlab platform.
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development specificity and sublethal effects of symbiont conferred resistance to parasitoids in Aphids
Functional Ecology, 2012Co-Authors: Maike Schmid, Raphael N Sieber, Yannickserge Zimmermann, Christoph VorburgerAbstract:Summary 1. One of the most exciting recent discoveries in the field of ecological immunology has been that insects employ the help of heritable symbionts as a defence against parasitoids and pathogens. Aphids commonly harbour the facultative bacterial endosymbiont Hamiltonella defensa, which is known to increase their resistance to parasitoids. It is unknown how this resistance develops during the Aphids’ ontogeny, following the transmission bottleneck between mother and offspring, and how specific symbiont-conferred defences are. 2. We addressed these issues in the black bean Aphid, Aphis fabae, by exposing Aphids of different age classes to the parasitoid Lysiphlebus fabarum. The susceptibility of Aphids that were either naturally or experimentally infected with H. defensa was compared with that of uninfected Aphids. 3. Susceptibility to parasitoids decreased with Aphid age, but Aphids harbouring H. defensa showed an earlier and/or steeper decline to lower levels of susceptibility than Aphids without this symbiont. This is consistent with the hypothesis that during Aphid development, symbiont-conferred resistance builds up with bacterial population growth, which we documented using quantitative polymerase chain reaction (qPCR). 4. Parasitoids that successfully overcame the symbiont-conferred resistance still suffered from sublethal effects of H. defensa. They exhibited lower emergence, delayed development and reduced size compared with parasitoids developing in Aphids without H. defensa. 5. The most striking result was a strong interaction on the rates of parasitism between Aphid sublines infected with different isolates of H. defensa and the parasitoid lines they were exposed to, suggesting a high specificity of symbiont-conferred resistance. 6. Based on these results, we conclude that when faced with hosts possessing H. defensa, Aphid parasitoids are under selection to preferentially attack the youngest host stages and/or to discriminate against symbiont-protected Aphids. Furthermore, the specificity induced by H. defensa in the interaction between host and parasitoid is likely to have important consequences for co-evolution. It may result in negative frequency-dependent selection and thus promote genotypic variation.
George E. Heimpel - One of the best experts on this subject based on the ideXlab platform.
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impact of the parasitoid aphelinus certus on soybean Aphid populations
Biological Control, 2018Co-Authors: Joe M Kaser, George E. HeimpelAbstract:Abstract Aphelinus certus Yasnosh (Hymenoptera: Aphelinidae) is an accidentally introduced parasitoid of the soybean Aphid, Aphis glycines Matsumura (Hemiptera: Aphididae) in North America and it has become one of the most common natural enemies of soybean Aphids in its adventive range. It is unclear, however, if increased prevalence of A. certus has resulted in increased biological control. We conducted an exclusion-cage experiment designed to isolate the impact of parasitoids from that of other resident natural enemies (mainly predators) of the soybean Aphid. We found that A. certus greatly outnumbered all other soybean Aphid parasitoids, and that it significantly reduced soybean Aphid populations over a time span of less than two weeks compared to controls. Moreover, parasitoids alone resulted in Aphid densities that were statistically equivalent to the combined effect of predators and parasitoids. Across all treatment cages, there was a significant negative association between parasitism rate and Aphid population growth, with predicted zero Aphid growth occurring at a parasitism rate of 42.2%.
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The Endosymbiont Arsenophonus Is Widespread in Soybean Aphid, Aphis glycines, but Does Not Provide Protection from Parasitoids or a Fungal Pathogen
2016Co-Authors: Jason A. Wulff, Karrie A Buckman, George E. Heimpel, Jennifer A WhiteAbstract:Aphids commonly harbor bacterial facultative symbionts that have a variety of effects upon their Aphid hosts, including defense against hymenopteran parasitoids and fungal pathogens. The soybean Aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is infected with the symbiont Arsenophonus sp., which has an unknown role in its Aphid host. Our research goals were to document the infection frequency and diversity of the symbiont in field-collected soybean Aphids, and to determine whether Arsenophonus is defending soybean Aphid against natural enemies. We performed diagnostic PCR and sequenced four Arsenophonus genes in soybean Aphids from their native and introduced range to estimate infection frequency and genetic diversity, and found that Arsenophonus infection is highly prevalent and genetically uniform. To evaluate the defensive role of Arsenophonus, we cured two Aphid genotypes of their natural Arsenophonus infection through ampicillin microinjection, resulting in infected and uninfected isolines within the same genetic background. These isolines were subjected to parasitoid assays using a recently introduced biological control agent, Binodoxys communis [Braconidae], a naturally recruited parasitoid, Aphelinus certus [Aphelinidae], and a commercially available biological control agent, Aphidius colemani [Braconidae]. We also assayed the effect of the common Aphid fungal pathogen, Pandora neoAphidis (Remaudiere & Hennebert) Humber (Entomophthorales: Entomophthoraceae), on the same Aphid isolines. We did not find differences in successful parasitism for any of the parasitoid species, nor did we fin
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worldwide populations of the Aphid aphis craccivora are infected with diverse facultative bacterial symbionts
Microbial Ecology, 2014Co-Authors: Cristina M Brady, Jason A. Wulff, Mark K Asplen, Keith R. Hopper, Catherine R. Linnen, Kerry M Oliver, Nicolas Desneux, George E. Heimpel, Jennifer A WhiteAbstract:Facultative bacterial endosymbionts can play an important role in the evolutionary trajectory of their hosts. Aphids (Hemiptera: Aphididae) are infected with a wide variety of facultative endosymbionts that can confer ecologically relevant traits, which in turn may drive microevolutionary processes in a dynamic selective environment. However, relatively little is known about how symbiont diversity is structured in most Aphid species. Here, we investigate facultative symbiont species richness and prevalence among worldwide populations of the cowpea Aphid, Aphis craccivora Koch. We surveyed 44 populations of A. craccivora, and detected 11 strains of facultative symbiotic bacteria, representing six genera. There were two significant associations between facultative symbiont and Aphid food plant: the symbiont Arsenophonus was found at high prevalence in A. craccivora populations collected from Robinia sp. (locust), whereas the symbiont Hamiltonella was almost exclusively found in A. craccivora populations from Medicago sativa (alfalfa). Aphids collected from these two food plants also had divergent mitochondrial haplotypes, potentially indicating the formation of specialized Aphid lineages associated with food plant (host-associated differentiation). The role of facultative symbionts in this process remains to be determined. Overall, observed facultative symbiont prevalence in A. craccivora was lower than that of some other well-studied Aphids (e.g., Aphis fabae and Acyrthosiphon pisum), possibly as a consequence of A. craccivora's almost purely parthenogenetic life history. Finally, most (70 %) of the surveyed populations were polymorphic for facultative symbiont infection, indicating that even when symbiont prevalence is relatively low, symbiont-associated phenotypic variation may allow population-level evolutionary responses to local selection.
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the endosymbiont arsenophonus is widespread in soybean Aphid aphis glycines but does not provide protection from parasitoids or a fungal pathogen
PLOS ONE, 2013Co-Authors: Jason A. Wulff, Karrie A Buckman, George E. Heimpel, Kongming Wu, Jennifer A WhiteAbstract:Aphids commonly harbor bacterial facultative symbionts that have a variety of effects upon their Aphid hosts, including defense against hymenopteran parasitoids and fungal pathogens. The soybean Aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is infected with the symbiont Arsenophonus sp., which has an unknown role in its Aphid host. Our research goals were to document the infection frequency and diversity of the symbiont in field-collected soybean Aphids, and to determine whether Arsenophonus is defending soybean Aphid against natural enemies. We performed diagnostic PCR and sequenced four Arsenophonus genes in soybean Aphids from their native and introduced range to estimate infection frequency and genetic diversity, and found that Arsenophonus infection is highly prevalent and genetically uniform. To evaluate the defensive role of Arsenophonus, we cured two Aphid genotypes of their natural Arsenophonus infection through ampicillin microinjection, resulting in infected and uninfected isolines within the same genetic background. These isolines were subjected to parasitoid assays using a recently introduced biological control agent, Binodoxys communis [Braconidae], a naturally recruited parasitoid, Aphelinus certus [Aphelinidae], and a commercially available biological control agent, Aphidius colemani [Braconidae]. We also assayed the effect of the common Aphid fungal pathogen, Pandora neoAphidis (Remaudiere & Hennebert) Humber (Entomophthorales: Entomophthoraceae), on the same Aphid isolines. We did not find differences in successful parasitism for any of the parasitoid species, nor did we find differences in P. neoAphidis infection between our treatments. Our conclusion is that Arsenophonus does not defend its soybean Aphid host against these major parasitoid and fungal natural enemies.
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combined effects of host plant resistance and intraguild predation on the soybean Aphid parasitoid binodoxys communis in the field
Biological Control, 2012Co-Authors: Juan Matias Chacon, Mark K Asplen, George E. HeimpelAbstract:Soybean varieties that exhibit resistance to the soybean Aphid Aphis glycines have been developed for use in North America. In principle, host-plant resistance to soybean Aphid can influence the interactions between the soybean Aphid and its natural enemies. Resistance could change the quality of soybean Aphids as a food source, the availability of soybean Aphids, or resistance traits could directly affect Aphid predators and parasitoids. Here, we focus on the effect of soybean Aphid resistance on the interactions between soybean Aphids, the parasitoid Binodoxys communis (Hymenoptera: Braconidae), and predators of these two species. We determined whether host-plant resistance affected within-season persistence of B. communis by releasing parasitoids into resistant and susceptible soybean plots. We observed higher B. communis densities in susceptible soybean plots than in resistant plots. There were also higher overall levels of intraguild predation of B. communis in susceptible plots, although the per-capita risk of intraguild predation of B. communis was affected neither by plant genotype nor by Aphid density. We discuss these effects and whether they were caused by direct effects of the resistant plants on B. communis or indirect effects through soybean Aphid or predators.
Robert J Oneil - One of the best experts on this subject based on the ideXlab platform.
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two year oscillation cycle in abundance of soybean Aphid in indiana
Agricultural and Forest Entomology, 2010Co-Authors: Marc Rhainds, Dave Voegtlin, Diana Castillo, Claire E Rutledge, Steve Yaninek, Clifford S Sadof, Pavel Kindlmann, Robert J OneilAbstract:1 The present study evaluated the population dynamics of the heteroecious soybean Aphid Aphis glycines Matsumura (Hemiptera: Aphididae) during an 8-year period in Indiana, shortly after its detection in North America. Sampling conducted at multiple locations revealed that A. glycines exhibited a 2-year oscillation cycle that repeated itself four times between 2001 and 2008: years of low Aphid abundance were consistently followed by years of high Aphid abundance. 2 Similar patterns of abundance of A. glycines and coccinellids (Coleoptera: Coccinellidae) in soybean fields, both within and between-years, suggest that late season predation by coccinellids plays a role in the oscillatory cycle of Aphids. Insidious flower bugs Orius insidiosus (Say) (Hemiptera: Anthocoridae) were numerically more abundant than coccinellids, although the lack of synchrony between Aphids and predatory bugs suggests that O. insidiosus has a limited influence on between-year variations in Aphid density. 3 The inverse relationship between Aphid densities before and after the start of the autumn migratory period changes direction in alternate years. High Aphid density on soybean in the summer is associated with a reduced number of alate migrants produced in the autumn. Conversely, years with low density Aphids on soybean in the summer are characterized by high numbers of alates that migrate to the primary host in the autumn. 4 From a pest management perspective, the 2-year oscillation cycle of A. glycines is a desirable attribute with respect to population dynamics because it implies that Aphids cause significant economic damage only in alternate years (as opposed to every year). Cultural practices enhancing the conservation biological control of Coccinellidae may help to preserve the periodicity of Aphid infestation and restrict the pest status of A. glycines.
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potential of suction traps as a monitoring tool for aphis glycines hemiptera Aphididae in soybean fields
Journal of Economic Entomology, 2010Co-Authors: Marc Rhainds, Steve Yaninek, David J Voegtlin, Clifford S Sadof, Kevin L Steffey, Robert J OneilAbstract:The current study evaluated the potential of using counts of winged adults captured in suction traps to forecast the local abundance of soybean Aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), in soybean, Glycine max (L.) Merr., fields. The abundance of Aphids was evaluated weekly by sampling plants in four to 11 soybean fields and recording the number of Aphids in suction traps between 2006 and 2008 in four counties in Indiana and Illinois. Fields in each county were located within 10 km of their respective suction trap, which allowed us to evaluate the relation between Aphid abundance on soybean plants and in suction traps at the county level. Migrant soybean Aphids caught in suction traps exhibited distinct seasonal trends each year: in 2006, trapped migrants consisted predominantly of individuals dispersing from soybean to buckthorn (Rhamnus sp.); in 2007, in contrast, the majority of trapped migrants were apparently individuals dispersing among soybean fields. The cumulative number of Aphids captured in suction traps was positively related to Aphid densities on soybean plants. However, the utility of suction traps as a monitoring tool may be limited by the variation in temporal patterns observed in suction traps and on soybean plants each year, and the spatial variation in Aphid abundance among soybean fields within a county.
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suppression of population growth of the soybean Aphid aphis glycines matsumura by predators the identification of a key predator and the effects of prey dispersion predator abundance and temperature
Environmental Entomology, 2006Co-Authors: Nicolas Desneux, Robert J OneilAbstract:The soybean Aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), has recently invaded North America from Asia and has become a major pest in soybean. Using field surveys and cage exclusion techniques, we identified the effect of natural enemies and abiotic factors on the growth of soybean Aphid populations in 2004 and 2005. The soybean Aphid population was significantly limited by natural enemies in the field. Generalist predators dominated the natural enemy community. One species, Orius insidiosus Say (Hemiptera: Anthocoridae) represented 85–90% of predators found. There was a significant negative relationship between Aphid population growth and O. insidiosus abundance. For other predators, there were no relationships between abundance and Aphid population growth. The spatial distribution of Aphids among plants affected the impact of O. insidiosus on Aphid population growth. When Aphids were distributed in a clumped manner, increases in O. insidiosus numbers resulted in lower Aphid growth rates. For randomly distributed Aphids, there was no effect of O. insidiosus abundance on Aphid population growth. Finally, we found no relationship between Aphid population growth and degree-day accumulations. The potential of O. insidiosus to suppress soybean Aphid population growth at low Aphid numbers and the importance of the predator to soybean Aphid integrated pest management are discussed.
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defensive response of soybean Aphid hemiptera Aphididae to predation by insidious flower bug hemiptera anthocoridae
Annals of The Entomological Society of America, 2006Co-Authors: Casey D Butler, Robert J OneilAbstract:During research on the life history characteristics of insidious flower bug, Orius insidiosus (Say), fed soybean Aphids, Aphis glycines Matsumura, the mouthparts of some predators were covered by a substance excreted from the cornicles of attacked Aphids. The cornicle exudate was found to encumber both nymphs and adults of O. insidiosus causing death because of molting failure and starvation. Among predator stages, first instars were most severely affected. Feeding frequency affected the number of predators affected by the exudate, with predators fed more often having higher rates of exudate exposure and mortality. Soybean Aphids produce exudate during all life stages, and its production does not seem to compromise the survival of the Aphid. The exudate also seems to contain an alarm pheromone as evidenced by increased movement and activity of Aphids in the vicinity of exudate-producing Aphids. The potential impact of the Aphid’s cornicle defenses on Aphid–predator dynamics in soybean, Glycine max (L.) Merr., is discussed.
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soybean plant stage and population growth of soybean Aphid
Journal of Economic Entomology, 2006Co-Authors: Claire E Rutledge, Robert J OneilAbstract:The soybean Aphid, Aphis glycines Matsumura, is a newly invasive species of Aphid in North America. Previous studies disagree as to whether soybean, Glycine max (L.) Merr., plant stage has an impact on Aphid intrinsic rate of increase. Therefore, the growth rate of soybean Aphids on soybean plants of different stages was examined at two different scales in the field. A planting date experiment was used to measure the population growth of soybean Aphids on plants of different stages. Clip-cages were used to measure life history characteristics of individual Aphids on plants of different stages. No differences were found in the population growth or dynamics of soybean Aphids in the planting date experiment. The life history characteristics of individual Aphids also showed no significant difference when feeding on different growth stages of soybean plants. The impact of these findings on soybean Aphid management is discussed and the possible reasons why the results differ from previous estimates of the Aphid growth–plant stage relationship are considered.
Zhi-juan Sun - One of the best experts on this subject based on the ideXlab platform.
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Host plants and obligate endosymbionts are not the sources for biosynthesis of the Aphid alarm pheromone.
Scientific reports, 2017Co-Authors: Zhi-juan SunAbstract:(E)-β-farnesene (EβF) is the major component of the alarm pheromone of many Aphid species, but where EβF is synthesized in Aphids is only partly understood. There are at least three most possible sources for the alarm pheromone: host plants, Aphid obligate endosymbiont and Aphids themselves. Here we eliminated the possibility of host plants and the obligate endosymbiont Buchnera Aphidicola as the sources for EβF released by Aphids. We excluded the possible effects of host plants on EβF biosynthesis by rearing Aphids on non-plant diets. Both the diet-reared Aphids, including the cotton Aphid Aphis gossypii and the green peach Aphid Myzus persicae, could still release EβF based on solid-phase micro-extraction combined with gas chromatography-mass spectrometer analysis. Meanwhile, we treated host Aphids with antibiotics to fully eliminate Buchnera bacteria. Though the treatment seriously affected the development and fecundity of host Aphids, the treated Aphids could still release EβF, and there was no significant difference in the EβF concentration as per the Aphid weight under different rearing conditions. Taken together, our experimental results suggest that host plants and obligate endosymbionts are not the sources for EβF released by Aphids, indicating that it is most probably the Aphid itself synthesizes the alarm pheromone.