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Sample records for aphid acyrthosiphon pisum

  1. Genome sequence of the pea aphid Acyrthosiphon pisum

    DEFF Research Database (Denmark)

    Richards, S.; Gibbs, R. A.; Gerardo, N. M.;

    2010-01-01

    Aphids are important agricultural pests and also biological models for studies of insect-plant interactions, symbiosis, virus vectoring, and the developmental causes of extreme phenotypic plasticity. Here we present the 464 Mb draft genome assembly of the pea aphid Acyrthosiphon pisum. This first...... published whole genome sequence of a basal hemimetabolous insect provides an outgroup to the multiple published genomes of holometabolous insects. Pea aphids are host-plant specialists, they can reproduce both sexually and asexually, and they have coevolved with an obligate bacterial symbiont. Here we...... include genes involved in chromatin modification, miRNA synthesis, and sugar transport. Gene losses include genes central to the IMD immune pathway, selenoprotein utilization, purine salvage, and the entire urea cycle. The pea aphid genome reveals that only a limited number of genes have been acquired...

  2. Neonicotinoid Binding, Toxicity and Expression of Nicotinic Acetylcholine Receptor Subunits in the Aphid Acyrthosiphon pisum

    OpenAIRE

    Taillebois, Emiliane; Beloula, Abdelhamid; Quinchard, Sophie; Jaubert-Possamai, Stéphanie; Daguin, Antoine; Servent, Denis; Tagu, Denis; Thany, Steeve H.; Tricoire-Leignel, Helene

    2014-01-01

    Neonicotinoid insecticides act on nicotinic acetylcholine receptor and are particularly effective against sucking pests. They are widely used in crops protection to fight against aphids, which cause severe damage. In the present study we evaluated the susceptibility of the pea aphid Acyrthosiphon pisum to the commonly used neonicotinoid insecticides imidacloprid (IMI), thiamethoxam (TMX) and clothianidin (CLT). Binding studies on aphid membrane preparations revealed the existence of high and ...

  3. Modification of Cry4Aa toward Improved Toxin Processing in the Gut of the Pea Aphid, Acyrthosiphon pisum

    OpenAIRE

    Rausch, Michael A.; Nanasaheb P Chougule; Deist, Benjamin R.; Bonning, Bryony C.

    2016-01-01

    Aphids are sap-sucking insects (order: Hemiptera) that cause extensive damage to a wide range of agricultural crops. Our goal was to optimize a naturally occurring insecticidal crystalline (Cry) toxins produced by the soil-dwelling bacterium Bacillus thuringiensis for use against the pea aphid, Acyrthosiphon pisum. On the basis that activation of the Cry4Aa toxin is a rate-limiting factor contributing to the relatively low aphicidal activity of this toxin, we introduced cathepsin L and cathep...

  4. The physiology of sterol nutrition in the pea aphid Acyrthosiphon pisum.

    Science.gov (United States)

    Bouvaine, Sophie; T Behmer, Spencer; Lin, George G; Faure, Marie-Line; Grebenok, Robert J; Douglas, Angela E

    2012-11-01

    The phloem sap of fava bean (Vicia faba) plants utilized by the pea aphid Acyrthosiphon pisum contains three sterols, cholesterol, stigmasterol and sitosterol, in a 2:2:1 ratio. To investigate the nutritional value of these sterols, pea aphids were reared on chemically-defined diets containing each sterol at 0.1, 1 and 10μgml(-1) with a sterol-free diet as control. Larval growth rate and aphid lifespan did not vary significantly across the diets, indicating that sterol reserves can buffer some performance indices against a shortfall in dietary sterol over at least one generation. However, lifetime reproductive output was depressed in aphids on diets containing stigmasterol or no sterol, relative to diets supplemented with cholesterol or sitosterol. The cholesterol density of embryos in teneral adults was significantly higher than in the total body; and the number and biomass of embryos in aphids on diets with stigmasterol and no sterols were reduced relative to diets with cholesterol or sitosterol, indicating that the reproductive output of the pea aphid can be limited by the amount and composition of dietary sterol. In a complementary RNA-seq analysis of pea aphids reared on plants and diets with different sterol contents, 7.6% of the 17,417 detected gene transcripts were differentially expressed. Transcript abundance of genes with annotated function in sterol utilization did not vary significantly among treatments, suggesting that the metabolic response to dietary sterol may be mediated primarily at the level of enzyme function or metabolite concentration. PMID:22878342

  5. Diapause in the pea aphid (Acyrthosiphon pisum is a slowing but not a cessation of development

    Directory of Open Access Journals (Sweden)

    Sisk Geoffroy C

    2003-08-01

    Full Text Available Abstract Background Many insects undergo a period of arrested development, called diapause, to avoid seasonally recurring adverse conditions. Whilst the phenology and endocrinology of insect diapause have been well studied, there has been comparatively little research into the developmental details of diapause. We investigated developmental aspects of diapause in sexually-produced embryos of the pea aphid, Acyrthosiphon pisum. Results We found that early stages of embryogenesis progressed at a temperature-independent rate, characteristic of diapause, whereas later stages of embryogenesis progressed at a temperature-dependent rate. However, embryos maintained at very high temperatures during the temperature-independent stage showed severe developmental abnormalities. Under no temperature regime did embryos display a distinct resting stage. Rather, morphological development progressed slowly but continuously throughout embryogenesis. Conclusion Diapause in the pea aphid, and perhaps in many other insects, is a temperature-independent slowing but not a cessation of morphological development. This suggests that the mechanisms limiting developmental rate during diapause may be the same as those controlling developmental rate at other stages of growth.

  6. New insight into the RNA interference response against cathepsin-L gene in the pea aphid, Acyrthosiphon pisum

    DEFF Research Database (Denmark)

    Sapountzis, Panagiotis; Duport, Gabrielle; Balmand, Séverine;

    2014-01-01

    RNA interference (RNAi) has been widely and successfully used for gene inactivation in insects, including aphids, where dsRNA administration can be performed either by feeding or microinjection. However, several aspects related to the aphid response to RNAi, as well as the influence......-L gene in the pea aphid, Acyrthosiphon pisum. In order to maximize the possibility of discovering specific phenotypes, the effect of the treatment was analyzed in single individual aphids at the level of five body compartments: the bacteriocytes, the gut, the embryonic chains, the head and the remaining...... body carcass. Our analysis revealed that gene expression knockdown effect in each single body compartment was dependent on the administration method used, and allowed us to discover new functions for the cathepsin-L gene in aphids. Injection of cathepsin-L dsRNA was much more effective on carcass...

  7. Neonicotinoid binding, toxicity and expression of nicotinic acetylcholine receptor subunits in the aphid Acyrthosiphon pisum.

    Directory of Open Access Journals (Sweden)

    Emiliane Taillebois

    Full Text Available Neonicotinoid insecticides act on nicotinic acetylcholine receptor and are particularly effective against sucking pests. They are widely used in crops protection to fight against aphids, which cause severe damage. In the present study we evaluated the susceptibility of the pea aphid Acyrthosiphon pisum to the commonly used neonicotinoid insecticides imidacloprid (IMI, thiamethoxam (TMX and clothianidin (CLT. Binding studies on aphid membrane preparations revealed the existence of high and low-affinity binding sites for [3H]-IMI (Kd of 0.16 ± 0.04 nM and 41.7 ± 5.9 nM and for the nicotinic antagonist [125I]-α-bungarotoxin (Kd of 0.008 ± 0.002 nM and 1.135 ± 0.213 nM. Competitive binding experiments demonstrated that TMX displayed a higher affinity than IMI for [125I]-α-bungarotoxin binding sites while CLT affinity was similar for both [125I]-α-bungarotoxin and [3H]-IMI binding sites. Interestingly, toxicological studies revealed that at 48 h, IMI (LC50 = 0.038 µg/ml and TMX (LC50 = 0.034 µg/ml were more toxic than CLT (LC50 = 0.118 µg/ml. The effect of TMX could be associated to its metabolite CLT as demonstrated by HPLC/MS analysis. In addition, we found that aphid larvae treated either with IMI, TMX or CLT showed a strong variation of nAChR subunit expression. Using semi-quantitative PCR experiments, we detected for all insecticides an increase of Apisumα10 and Apisumβ1 expressions levels, whereas Apisumβ2 expression decreased. Moreover, some other receptor subunits seemed to be differently regulated according to the insecticide used. Finally, we also demonstrated that nAChR subunit expression differed during pea aphid development. Altogether these results highlight species specificity that should be taken into account in pest management strategies.

  8. Evaluation of the susceptibility of the pea aphid, Acyrthosiphon pisum, to a selection of novel biorational insecticides using an artificial diet

    OpenAIRE

    Sadeghi, Amin; Van Damme, Els; Smagghe, Guy

    2009-01-01

    An improved technique was developed to assay the toxicity of insecticides against aphids using an artificial diet. The susceptibility of the pea aphid Acyrthosiphon pisum (Harris) (Hemiptera: Aphidoidea) was determined for a selection of novel biorational insecticides, each representing a novel mode of action. Flonicamid, a novel systemic insecticide with selective activity as feeding blocker against sucking insects, showed high toxicity against first-instar A. pisum nymphs with an LC50 of 20...

  9. Cytochrome P450 gene, CYP4G51, modulates hydrocarbon production in the pea aphid, Acyrthosiphon pisum.

    Science.gov (United States)

    Chen, Nan; Fan, Yong-Liang; Bai, Yu; Li, Xiang-Dong; Zhang, Zhan-Feng; Liu, Tong-Xian

    2016-09-01

    Terrestrial insects deposit a layer of hydrocarbons (HCs) as waterproofing agents on their epicuticle. The insect-specific CYP4G genes, subfamily members of P450, have been found in all insects with sequenced genomes to date. They are critical for HC biosynthesis in Drosophila; however, their functional roles in other insects including the piercing-sucking hemipterous aphids remain unknown. In this study, we presented the molecular characterization and a functional study of the CYP4G51 gene in the pea aphid, Acyrthosiphon pisum (Harris). CYP4G51 transcript was detectable across the whole life cycle of A. pisum, and was prominently expressed in the aphid head and abdominal cuticle. Up-regulation of CYP4G51 under desiccation stress was more significant in the third instar nymphs compared with the adults. Also, up-regulation of CYP4G51 was observed when the aphids fed on an artificial diet compared with those fed on the broad bean plant, and was positively correlated with a high level of cuticular HCs (CHCs). RNAi knockdown of CYP4G51 significantly reduced its expression and caused reductions in both internal and external HCs. A deficiency in CHCs resulted in aphids being more susceptible to desiccation, with increased mortality under desiccation stress. The current results confirm that CYP4G51 modulates HC biosynthesis to protect aphids from desiccation. Moreover, our data also indicate that saturated and straight-chain HCs play a major role in cuticular waterproofing in the pea aphid. A. pisum CYP4G51 could be considered as a novel RNAi target in the field of insect pest management. PMID:27425674

  10. Modification of Cry4Aa toward Improved Toxin Processing in the Gut of the Pea Aphid, Acyrthosiphon pisum.

    Directory of Open Access Journals (Sweden)

    Michael A Rausch

    Full Text Available Aphids are sap-sucking insects (order: Hemiptera that cause extensive damage to a wide range of agricultural crops. Our goal was to optimize a naturally occurring insecticidal crystalline (Cry toxins produced by the soil-dwelling bacterium Bacillus thuringiensis for use against the pea aphid, Acyrthosiphon pisum. On the basis that activation of the Cry4Aa toxin is a rate-limiting factor contributing to the relatively low aphicidal activity of this toxin, we introduced cathepsin L and cathepsin B cleavage sites into Cry4Aa for rapid activation in the aphid gut environment. Incubation of modified Cry4Aa and aphid proteases in vitro demonstrated enhanced processing of the toxin into the active form for some of the modified constructs relative to non-modified Cry4Aa. Aphids fed artificial diet with toxin at a final concentration of 125 μg/ml showed enhanced mortality after two days for one of the four modified constructs. Although only modest toxin improvement was achieved by use of this strategy, such specific toxin modifications designed to overcome factors that limit aphid toxicity could be applied toward managing aphid populations via transgenic plant resistance.

  11. Modification of Cry4Aa toward Improved Toxin Processing in the Gut of the Pea Aphid, Acyrthosiphon pisum.

    Science.gov (United States)

    Rausch, Michael A; Chougule, Nanasaheb P; Deist, Benjamin R; Bonning, Bryony C

    2016-01-01

    Aphids are sap-sucking insects (order: Hemiptera) that cause extensive damage to a wide range of agricultural crops. Our goal was to optimize a naturally occurring insecticidal crystalline (Cry) toxins produced by the soil-dwelling bacterium Bacillus thuringiensis for use against the pea aphid, Acyrthosiphon pisum. On the basis that activation of the Cry4Aa toxin is a rate-limiting factor contributing to the relatively low aphicidal activity of this toxin, we introduced cathepsin L and cathepsin B cleavage sites into Cry4Aa for rapid activation in the aphid gut environment. Incubation of modified Cry4Aa and aphid proteases in vitro demonstrated enhanced processing of the toxin into the active form for some of the modified constructs relative to non-modified Cry4Aa. Aphids fed artificial diet with toxin at a final concentration of 125 μg/ml showed enhanced mortality after two days for one of the four modified constructs. Although only modest toxin improvement was achieved by use of this strategy, such specific toxin modifications designed to overcome factors that limit aphid toxicity could be applied toward managing aphid populations via transgenic plant resistance. PMID:27171411

  12. Nicotinic Acetylcholine Receptor Gene Family of the Pea Aphid, Acyrthosiphon pisum

    Institute of Scientific and Technical Information of China (English)

    LIU Yi-peng; LIN Ke-jian; LIU Yang; GUI Fu-rong; WANG Gui-rong

    2013-01-01

    The nicotinic acetylcholine receptors (nAchRs) are cholinergic receptors that form ligand-gated ion channels by ifve subunits in insect and vertebrate nervous systems. The insect nAChR is the molecular target of a class of insecticides, neonicotinoids. Here, we identiifed and cloned 11 candidate nAChR subunit genes in Acyrthosiphon pisum using genome-based bioinformatics combined modern molecular techniques. Most A. pisum nAChRs including α1, α2, α3, α4, α6, α8, and β1 show highly sequence identities with the counterparts of other insects examined. Expression proifles analysis showed that all subunit genes were expressed in adult head. At least two subunits have alternative splicing that obviously increase A. pisum nicotinic receptor diversity. This study will be invaluable for exploring the molecular mechanisms of neonicotinoid-like insecticides in sucking pests, and for ultimately establishing the screening platform of novel insecticides.

  13. Revisiting the anatomy of the central nervous system of a hemimetabolous model insect species: the pea aphid Acyrthosiphon pisum.

    Science.gov (United States)

    Kollmann, Martin; Minoli, Sebastian; Bonhomme, Joël; Homberg, Uwe; Schachtner, Joachim; Tagu, Denis; Anton, Sylvia

    2011-02-01

    Aphids show a marked phenotypic plasticity, producing asexual or sexual and winged or wingless morphs depending on environmental conditions and season. We describe here the general structure of the brain of various morphs of the pea aphid Acyrthosiphon pisum. This is the first detailed anatomical study of the central nervous system of an aphid by immunocytochemistry (synapsin, serotonin, and several neuropeptides), ethyl-gallate staining, confocal laser scanning microscopy, and three-dimensional reconstructions. The study has revealed well-developed optic lobes composed of lamina, medulla, and lobula complex. Ocelli are only present in males and winged parthenogenetic females. The central complex is well-defined, with a central body divided into two parts, a protocerebral bridge, and affiliated lateral accessory lobes. The mushroom bodies are ill-defined, lacking calyces, and only being visualized by using an antiserum against the neuropeptide orcokinin. The antennal lobes contain poorly delineated glomeruli but can be clearly visualized by performing antennal backfills. On the basis of our detailed description of the brain of winged and wingless parthenogenetic A. pisum females, an anatomical map is now available that should improve our knowledge of the way that these structures are involved in the regulation of phenotypic plasticity.

  14. Gene expression analysis of parthenogenetic embryonic development of the pea aphid, Acyrthosiphon pisum, suggests that aphid parthenogenesis evolved from meiotic oogenesis.

    Directory of Open Access Journals (Sweden)

    Dayalan G Srinivasan

    Full Text Available Aphids exhibit a form of phenotypic plasticity, called polyphenism, in which genetically identical females reproduce sexually during one part of the life cycle and asexually (via parthenogenesis during the remainder of the life cycle. The molecular basis for aphid parthenogenesis is unknown. Cytological observations of aphid parthenogenesis suggest that asexual oogenesis evolved either through a modification of meiosis or from a mitotic process. As a test of these alternatives, we assessed the expression levels and expression patterns of canonical meiotic recombination and germline genes in the sexual and asexual ovaries of the pea aphid, Acyrthosiphon pisum. We observed expression of all meiosis genes in similar patterns in asexual and sexual ovaries, with the exception that some genes encoding Argonaute-family members were not expressed in sexual ovaries. In addition, we observed that asexual aphid tissues accumulated unspliced transcripts of Spo11, whereas sexual aphid tissues accumulated primarily spliced transcripts. In situ hybridization revealed Spo11 transcript in sexual germ cells and undetectable levels of Spo11 transcript in asexual germ cells. We also found that an obligately asexual strain of pea aphid produced little spliced Spo11 transcript. Together, these results suggest that parthenogenetic oogenesis evolved from a meiosis-like, and not a mitosis-like, process and that the aphid reproductive polyphenism may involve a modification of Spo11 gene activity.

  15. Stable isotope studies reveal pathways for the incorporation of non-essential amino acids in Acyrthosiphon pisum (pea aphids).

    Science.gov (United States)

    Haribal, Meena; Jander, Georg

    2015-12-01

    Plant roots incorporate inorganic nitrogen into the amino acids glutamine, glutamic acid, asparagine and aspartic acid, which together serve as the primary metabolites of nitrogen transport to other tissues. Given the preponderance of these four amino acids, phloem sap is a nutritionally unbalanced diet for phloem-feeding insects. Therefore, aphids and other phloem feeders typically rely on microbial symbionts for the synthesis of essential amino acids. To investigate the metabolism of the four main transport amino acids by the pea aphid (Acyrthosiphon pisum), and its Buchnera aphidicola endosymbionts, aphids were fed defined diets with stable isotope-labeled glutamine, glutamic acid, asparagine or aspartic acid (U-(13)C, U-(15)N; U-(15)N; α-(15)N; or γ-(15)N). The metabolic fate of the dietary (15)N and (13)C was traced using gas chromatography-mass spectrometry (GC-MS). Nitrogen was the major contributor to the observed amino acid isotopomers with one additional unit mass (M+1). However, there was differential incorporation, with the amine nitrogen of asparagine being incorporated into other amino acids more efficiently than the amide nitrogen. Higher isotopomers (M+2, M+3 and M+4) indicated the incorporation of varying numbers of (13)C atoms into essential amino acids. GC-MS assays also showed that, even with an excess of dietary labeled glutamine, glutamic acid, asparagine or aspartic acid, the overall content of these amino acids in aphid bodies was mostly the product of catabolism of dietary amino acids and subsequent re-synthesis within the aphids. Thus, these predominant dietary amino acids are not passed directly to Buchnera endosymbionts for synthesis of essential amino acids, but are rather are produced de novo, most likely by endogenous aphid enzymes. PMID:26632455

  16. Dickeya dadantii, a plant pathogenic bacterium producing Cyt-like entomotoxins, causes septicemia in the pea aphid Acyrthosiphon pisum.

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    Denis Costechareyre

    Full Text Available Dickeya dadantii (syn. Erwinia chrysanthemi is a plant pathogenic bacteria that harbours a cluster of four horizontally-transferred, insect-specific toxin genes. It was recently shown to be capable of causing an acute infection in the pea aphid Acyrthosiphon pisum (Insecta: Hemiptera. The infection route of the pathogen, and the role and in vivo expression pattern of these toxins, remain unknown. Using bacterial numeration and immunolocalization, we investigated the kinetics and the pattern of infection of this phytopathogenic bacterium within its insect host. We compared infection by the wild-type strain and by the Cyt toxin-deficient mutant. D. dadantii was found to form dense clusters in many luminal parts of the aphid intestinal tract, including the stomach, from which it invaded internal tissues as early as day 1 post-infection. Septicemia occurred soon after, with the fat body being the main infected tissue, together with numerous early infections of the embryonic chains showing embryonic gut and fat body as the target organs. Generalized septicemia led to insect death when the bacterial load reached about 10(8 cfu. Some individual aphids regularly escaped infection, indicating an effective partial immune response to this bacteria. Cyt-defective mutants killed insects more slowly but were capable of localisation in any type of tissue. Cyt toxin expression appeared to be restricted to the digestive tract where it probably assisted in crossing over the first cell barrier and, thus, accelerating bacterial diffusion into the aphid haemocel. Finally, the presence of bacteria on the surface of leaves hosting infected aphids indicated that the insects could be vectors of the bacteria.

  17. Identification of distinct quantitative trait loci associated with defence against the closely related aphids Acyrthosiphon pisum and A. kondoi in Medicago truncatula

    KAUST Repository

    Guo, Su-Min

    2012-03-21

    Aphids are a major family of plant insect pests. Medicago truncatula and Acyrthosiphon pisum (pea aphid, PA) are model species with a suite of resources available to help dissect the mechanism underlying plant-aphid interactions. A previous study focused on monogenic and relatively strong resistance in M. truncatula to PA and other aphid species. In this study a moderate resistance to PA was characterized in detail in the M. truncatula line A17 and compared with the highly susceptible line A20 and the more resistant line Jester. The results show that PA resistance in A17 involves both antibiosis and tolerance, and that resistance is phloem based. Quantitative trait locus (QTL) analysis using a recombinant inbred line (RIL) population (n=114) from a cross between A17 and A20 revealed that one locus, which co-segregated with AIN (Acyrthosiphon-induced necrosis) on chromosome 3, is responsible for the reduction of aphid biomass (indicator of antibiosis) for both PA and bluegreen aphid (BGA, A. kondoi), albeit to a lesser degree for PA than BGA. Interestingly, two independent loci on chromosomes 5 and 3 were identified for the plant biomass reduction (indicator of plant tolerance) by PA and BGA, respectively, demonstrating that the plant\\'s tolerance response to these two closely related aphid species is distinct. Together with previously identified major resistant (R) genes, the QTLs identified in this study are powerful tools to understand fully the spectrum of plant defence against sap-sucking insects and provide opportunities for breeders to generate effective and sustainable strategies for aphid control. 2012 The Author.

  18. Selection of reference genes for expression analysis using quantitative real-time PCR in the pea aphid, Acyrthosiphon pisum (Harris (Hemiptera, Aphidiae.

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    Chunxiao Yang

    Full Text Available To facilitate gene expression study and obtain accurate qRT-PCR analysis, normalization relative to stable expressed housekeeping genes is required. In this study, expression profiles of 11 candidate reference genes, including actin (Actin, elongation factor 1 α (EF1A, TATA-box-binding protein (TATA, ribosomal protein L12 (RPL12, β-tubulin (Tubulin, NADH dehydrogenase (NADH, vacuolar-type H+-ATPase (v-ATPase, succinate dehydrogenase B (SDHB, 28S ribosomal RNA (28S, 16S ribosomal RNA (16S, and 18S ribosomal RNA (18S from the pea aphid Acyrthosiphon pisum, under different developmental stages and temperature conditions, were investigated. A total of four analytical tools, geNorm, Normfinder, BestKeeper, and the ΔCt method, were used to evaluate the suitability of these genes as endogenous controls. According to RefFinder, a web-based software tool which integrates all four above-mentioned algorithms to compare and rank the reference genes, SDHB, 16S, and NADH were the three most stable house-keeping genes under different developmental stages and temperatures. This work is intended to establish a standardized qRT-PCR protocol in pea aphid and serves as a starting point for the genomics and functional genomics research in this emerging insect model.

  19. Genomic evidence for complementary purine metabolism in the pea aphid, Acyrthosiphon pisum, and its symbiotic bacterium Buchnera aphidicola.

    Science.gov (United States)

    Ramsey, J S; MacDonald, S J; Jander, G; Nakabachi, A; Thomas, G H; Douglas, A E

    2010-03-01

    The purine salvage pathway recycles purines to nucleotides, promoting efficient utilization of purine nucleotides. Exceptionally among animals with completely sequenced genomes, the pea aphid lacks key purine recycling genes that code for purine nucleoside phosphorylase and adenosine deaminase, indicating that the aphid can neither metabolize nucleosides to the corresponding purines, nor adenosine to inosine. Purine metabolism genes in the symbiotic bacterium Buchnera complement aphid genes, and Buchnera can meet its nucleotide requirement from aphid-derived guanosine. Buchnera demand for nucleosides may have relaxed the selection for purine recycling in the aphid, leading to the loss of key aphid purine salvage genes. Further, the coupled purine metabolism of aphid and Buchnera could contribute to the dependence of the pea aphid on this symbiosis.

  20. Taxonomy Icon Data: pea aphid [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available pea aphid Acyrthosiphon pisum Arthropoda Acyrthosiphon_pisum_L.png Acyrthosiphon_pisum_NL.png Acyrthosiph...on_pisum_S.png Acyrthosiphon_pisum_NS.png http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Acyrthosiph...on+pisum&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Acyrthosiphon+pisum&t=NL http:...//biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Acyrthosiphon+pisum&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Acyrthosiphon+pisum&t=NS ...

  1. Effects of biological insecticides NeemAzal T/S and Pyrethrum FS EC and their interaction with organic products in treatments of pea aphid Acyrthosiphon pisum (Harris (Hemiptera: Aphididae on Pisum sativum (L.

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    Ivelina Nikolova

    2014-09-01

    Full Text Available The efficacy and effects of two biological insecticides, NeemAzal T/S® and Pyrethrum FS EC, applied individually and in combination with Polyversum (a biological growth regulator and fungicide and Biofa (an organic foliar fertilizer, in controlling Acyrthosyphon pisum population density were studied. Nurelle D (a synthetic insecticide, applied alone and in combination with Flordimex 420 (a synthetic growth regulator, was used as a standard. The products were applied once (at budding stage or twice (at budding and flowering stages. Twenty-four variants were studied. The interaction of Pyrethrum with Biofa was the most efficient variant of the biological products, causing a reduction in aphid density that reached 48.2% after double treatment, while Pyrethrum+Polyversum (42.5% was the second most successful treatment. The combination of Pyrethrum with Biofa achieved the highest efficacy and synergism and their efficacy approached that of the synthetic insecticide.

  2. Solenopsis invicta virus 3: mapping of structural proteins, ribosomal frameshifting, and similarities to Acyrthosiphon pisum virus and Kelp fly virus.

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    Steven M Valles

    Full Text Available Solenopsis invicta virus 3 (SINV-3 is a positive-sense single-stranded RNA virus that infects the red imported fire ant, Solenopsis invicta. We show that the second open reading frame (ORF of the dicistronic genome is expressed via a frameshifting mechanism and that the sequences encoding the structural proteins map to both ORF2 and the 3' end of ORF1, downstream of the sequence that encodes the RNA-dependent RNA polymerase. The genome organization and structural protein expression strategy resemble those of Acyrthosiphon pisum virus (APV, an aphid virus. The capsid protein that is encoded by the 3' end of ORF1 in SINV-3 and APV is predicted to have a jelly-roll fold similar to the capsid proteins of picornaviruses and caliciviruses. The capsid-extension protein that is produced by frameshifting, includes the jelly-roll fold domain encoded by ORF1 as its N-terminus, while the C-terminus encoded by the 5' half of ORF2 has no clear homology with other viral structural proteins. A third protein, encoded by the 3' half of ORF2, is associated with purified virions at sub-stoichiometric ratios. Although the structural proteins can be translated from the genomic RNA, we show that SINV-3 also produces a subgenomic RNA encoding the structural proteins. Circumstantial evidence suggests that APV may also produce such a subgenomic RNA. Both SINV-3 and APV are unclassified picorna-like viruses distantly related to members of the order Picornavirales and the family Caliciviridae. Within this grouping, features of the genome organization and capsid domain structure of SINV-3 and APV appear more similar to caliciviruses, perhaps suggesting the basis for a "Calicivirales" order.

  3. Genetic Mapping of a Major Resistance Gene to Pea Aphid (Acyrthosipon pisum) in the Model Legume Medicago truncatula.

    Science.gov (United States)

    Kamphuis, Lars G; Guo, Su-Min; Gao, Ling-Ling; Singh, Karam B

    2016-01-01

    Resistance to the Australian pea aphid (PA; Acyrthosiphon pisum) biotype in cultivar Jester of the model legume Medicago truncatula is mediated by a single dominant gene and is phloem-mediated. The genetic map position for this resistance gene, APR (Acyrthosiphon pisum resistance), is provided and shows that APR maps 39 centiMorgans (cM) distal of the A. kondoi resistance (AKR) locus, which mediates resistance to a closely related species of the same genus bluegreen aphid (A. kondoi). The APR region on chromosome 3 is dense in classical nucleotide binding site leucine-rich repeats (NLRs) and overlaps with the region harbouring the RAP1 gene which confers resistance to a European PA biotype in the accession Jemalong A17. Further screening of a core collection of M. truncatula accessions identified seven lines with strong resistance to PA. Allelism experiments showed that the single dominant resistance to PA in M. truncatula accessions SA10481 and SA1516 are allelic to SA10733, the donor of the APR locus in cultivar Jester. While it remains unclear whether there are multiple PA resistance genes in an R-gene cluster or the resistance loci identified in the other M. truncatula accessions are allelic to APR, the introgression of APR into current M. truncatula cultivars will provide more durable resistance to PA. PMID:27483247

  4. Genetic Mapping of a Major Resistance Gene to Pea Aphid (Acyrthosipon pisum in the Model Legume Medicago truncatula

    Directory of Open Access Journals (Sweden)

    Lars G. Kamphuis

    2016-07-01

    Full Text Available Resistance to the Australian pea aphid (PA; Acyrthosiphon pisum biotype in cultivar Jester of the model legume Medicago truncatula is mediated by a single dominant gene and is phloem-mediated. The genetic map position for this resistance gene, APR (Acyrthosiphon pisum resistance, is provided and shows that APR maps 39 centiMorgans (cM distal of the A. kondoi resistance (AKR locus, which mediates resistance to a closely related species of the same genus bluegreen aphid (A. kondoi. The APR region on chromosome 3 is dense in classical nucleotide binding site leucine-rich repeats (NLRs and overlaps with the region harbouring the RAP1 gene which confers resistance to a European PA biotype in the accession Jemalong A17. Further screening of a core collection of M. truncatula accessions identified seven lines with strong resistance to PA. Allelism experiments showed that the single dominant resistance to PA in M. truncatula accessions SA10481 and SA1516 are allelic to SA10733, the donor of the APR locus in cultivar Jester. While it remains unclear whether there are multiple PA resistance genes in an R-gene cluster or the resistance loci identified in the other M. truncatula accessions are allelic to APR, the introgression of APR into current M. truncatula cultivars will provide more durable resistance to PA.

  5. Ultrastructural and cytochemical changes in Pelargonium leaves due to aphid (Acyrthosiphon pelargonii (Kalt. infestation

    Directory of Open Access Journals (Sweden)

    Joanna Ślusarczyk

    2012-12-01

    Full Text Available Infestation of aphid Acyrthosiphon pelargonii (Kalt. caused increased deposition of phenolic compounds in the leaves of Pelargonium sp. Most deposits were located in the vacuole and in the area between the plasma membrane and cell wall, as well as some in the intercellular spaces. In cytoplasm damages were observed involving tonoplast and numerous vesicle deposits in the vicinity of the plasma membrane. Endoplasmic reticulum and myelin structures increased in number, as well as mitochondria whose cristae were longer and larger. Thus, we observed both the increase of organelle activity in such cells and the segregation of damaged areas in the form of membrane degradation.

  6. Optimization of Agroinfiltration in Pisum sativum Provides a New Tool for Studying the Salivary Protein Functions in the Pea Aphid Complex.

    Science.gov (United States)

    Guy, Endrick; Boulain, Hélène; Aigu, Yoann; Le Pennec, Charlotte; Chawki, Khaoula; Morlière, Stéphanie; Schädel, Kristina; Kunert, Grit; Simon, Jean-Christophe; Sugio, Akiko

    2016-01-01

    Aphids are piercing-sucking insect pests and feed on phloem sap. During feeding, aphids inject a battery of salivary proteins into host plant. Some of these proteins function like effectors of microbial pathogens and influence the outcome of plant-aphid interactions. The pea aphid (Acyrthosiphon pisum) is the model aphid and encompasses multiple biotypes each specialized to one or a few legume species, providing an opportunity to investigate the underlying mechanisms of the compatibility between plants and aphid biotypes. We aim to identify the aphid factors that determine the compatibility with host plants, hence involved in the host plant specialization process, and hypothesize that salivary proteins are one of those factors. Agrobacterium-mediated transient gene expression is a powerful tool to perform functional analyses of effector (salivary) proteins in plants. However, the tool was not established for the legume species that A. pisum feeds on. Thus, we decided to optimize the method for legume plants to facilitate the functional analyses of A. pisum salivary proteins. We screened a range of cultivars of pea (Pisum sativum) and alfalfa (Medicago sativa). None of the M. sativa cultivars was suitable for agroinfiltration under the tested conditions; however, we established a protocol for efficient transient gene expression in two cultivars of P. sativum, ZP1109 and ZP1130, using A. tumefaciens AGL-1 strain and the pEAQ-HT-DEST1 vector. We confirmed that the genes are expressed from 3 to 10 days post-infiltration and that aphid lines of the pea adapted biotype fed and reproduced on these two cultivars while lines of alfalfa and clover biotypes did not. Thus, the pea biotype recognizes these two cultivars as typical pea plants. By using a combination of ZP1109 and an A. pisum line, we defined an agroinfiltration procedure to examine the effect of in planta expression of selected salivary proteins on A. pisum fitness and demonstrated that transient expression of

  7. An evaluation of the main cultivated Medicago sativa cultivars (strains) for Acyrthosiphon pisum resistance in Ningxia%宁夏主栽苜蓿品种(系)对豌豆蚜的抗性评价

    Institute of Scientific and Technical Information of China (English)

    马建华; 魏淑花; 张洪英; 张蓉; 李克昌; 罗晓玲; 张宇

    2016-01-01

    An evaluation of the 12 main Medicago sativa cultivars (strains)for aphid resistance was carried out using aphid ration and fuzzy recognition methods in field and indoor conditions in Ningxia.The aphid popula-tion in the field was complex,consisting mainly of Acyrthosiphon pisum (over 80% of the total aphid popula-tion).Field and indoor analysis showed that Surprising,WL343HQ and Derby were high susceptible strains, with aphid rations above 1.25 and significantly higher than the other cultivars.Platon,Zhongmu No.3 and Gannong No.4 were susceptible varieties,with aphid rations between 0.76 and 1.25.Pioneer was a middle re-sistant variety,with an aphid ration of 0.51.Santory,Crown,Queen,SR4030 and MF4020 were resistant va-rieties,with aphid rations between 0.26 and 0.50.Based on this study,a standard damage index of aphids to Medicago ,and aphid ration and fuzzy recognition methods,are recommended for evaluating aphid resistance in field and indoor situations.%运用蚜量比值法和模糊识别法,对12个宁夏主栽苜蓿品种(系)进行了田间和室内抗蚜评价试验。田间蚜虫种类以豌豆蚜(Acyrthosiphon pisum )为主,占混合种群数量的80%以上。田间和室内结果综合分析表明:供试12个苜蓿品种(品系)中,惊喜、WL343HQ 和德宝3个品种为高感品种,其蚜量比值均大于1.25,并与其他品种间差异极显著;柏拉图、中苜3号、甘农4号等3个品种为感蚜品种,其蚜量比值位于0.76~1.25之间;先行者为中抗品种,蚜量比值为0.51,位于0.51~0.75之间;皇冠、三得利、皇后、SR4030和 MF40205等5个品种为抗蚜品种,其蚜量比值0.26~0.50之间。同时,本研究也提出了室内和田间苜蓿抗蚜鉴定方法分别为模糊识别法和蚜量比值法的评价方法和标准。

  8. Can snow depth be used to predict the distribution of the high Arctic aphid Acyrthosiphon svalbardicum (Hemiptera: Aphididae on Spitsbergen?

    Directory of Open Access Journals (Sweden)

    Ávila-Jiménez María L

    2011-10-01

    Full Text Available Abstract Background The Svalbard endemic aphid Acyrthosiphon svalbardicum (Heikinheimo, 1968 is host specific to Dryas octopetala L. ssp octopetala (Rosaceae. It has been hypothesized that the aphid is present on those areas with a thin winter snow cover and which therefore clear of snow earlier in the season. This early snow clearance results in a longer growing period and allows the aphid to experience at least the minimum number of degree days required to complete its life cycle. However, this hypothesis lacked a detailed field validation. We aimed to test the relationship between the aphid distribution and time of snow clearance at landscape scale, mapping snow depth at peak of snow accumulation for the two succeeding years 2009 and 2010 and examining site occupancy and plant phenology the following summers. Additionally, the distribution range mapped by Strathdee & Bale (1995 was revisited to address possible changes in range along the coast of the fjord. Results A linear relation between snow depth and timing of snow melt was found but with strong inter-annual and landscape variation. Both snow depth and plant phenology were found to affect patch occupancy. In August, the aphid, at the three life stages scored (viviparae, oviparae/males and eggs, was present most frequently in those D. octopetala patches with the most advanced plant phenology and which showed shallower snow depths in spring. However, many patches predicted to contain aphids were empty. The aphid distribution range has expanded 4.7 km towards the fjord mouth from 1995. Conclusions Snow depth alone, and hence date of snow clearance, cannot precisely define species distribution at landscape scale, as this cannot explain why are they unoccupied patches under shallow snow depths with advanced plant phenology. We nonetheless present a model Arctic system that could form the basis for long term monitoring for climate- driven species shifts.

  9. Effects of Herbivore Stress by Acyrthosiphon pisum on the Contents of Tannin and Physiological Activity in Different Alfalfa Cultivars%豌豆蚜刺吸胁迫对不同苜蓿品种体内单宁含量及生理活性的影响

    Institute of Scientific and Technical Information of China (English)

    武德功; 王森山; 刘长仲; 胡桂馨; 杜军利; 贺春贵

    2011-01-01

    It is necessary to study the relationship between aphid stress and physiological activity in different alfalfa yarieties for breeding of resistant alfalfa varieties and sustainable control of aphids. The dynamics of Malondialdehyde (MDA) and Tannin contents and the activities of protective enzymes (Superoxide dismutase (SOD), Peroxidase (POD)) were studied in the leaves of four alfalfa cultivars, Gannong No. 5 (G5), Gannong No. 3 (G3), Gloden Empress (JH), and Hunter River (Hu), infested by pea aphid,Acyrthosiphon pisum Harris. Results show that the MDA contents of resistant variety (G5) were lower than that of the susceptible variety (Hu) and low resistant varieties (G3) when their leaves were piercingsucked by the aphid. The Tannin contents of resistant variety (G5) and the susceptible variety (Hu) were lower than that of the low resistant ones (G3 and JH), While the SOD and POD activities in the susceptible variety (Hu) appeared lower than that of the resistant variety (G5) and low resistant varieties (G3,JH). Throughout the period of aphid attacks, the activities of SOD and POD of all varieties rose initially then declined, whereas the dynamics of MDA and Tannin contents of four alfalfa cultivars were irregular.Therefore, under the aphid stress, the contents of MDA and the activity of SOD, POD in susceptible, low resistant and resistant varieties are closely related to the aphid-resistance of alfalfa. These biochemical markers may be used as physiological indices for aphid-resistance appraisal. However, the relationship between Tannin contents and aphid-resistance of alfalfa requires further research.%通过对甘农5号(G5)、甘农3号(G3)、金皇后(JH)和猎人河(Hu)4种不同抗蚜苜蓿(Medicago sativa L.)品种受豌豆蚜(Acyrthosiphon pisum)胁迫后其叶片内丙二醛(MDA)和单宁含量及防御性酶(超氧化物歧化酶(SOD)和过氧化物酶(POD))活性的动态变化研究,以期明确各项生理指标与抗虫性之间的关系.结果表

  10. Do plant viruses facilitate their aphid vectors by inducing symptoms that alter behavior and performance?

    Science.gov (United States)

    Hodge, Simon; Powell, Glen

    2008-12-01

    Aphids can respond both positively and negatively to virus-induced modifications of the shared host plant. It can be speculated that viruses dependent on aphids for their transmission might evolve to induce changes in the host plant that attract aphids and improve their performance, subsequently enhancing the success of the pathogen itself. We studied how pea aphids [Acyrthosiphon pisum (Harris)] responded to infection of tic beans (Vicia faba L.) by three viruses with varying degrees of dependence on this aphid for their transmission: pea enation mosaic virus (PEMV), bean yellow mosaic virus (BYMV), and broad bean mottle virus (BBMV). BYMV has a nonpersistent mode of transmission by aphids, whereas PEMV is transmitted in a circulative-persistent manner. BBMV is not aphid transmitted. When reared on plants infected by PEMV, no changes in aphid survival, growth, or reproductive performance were observed, whereas infection of beans by the other aphid-dependent virus, BYMV, actually caused a reduction in aphid survival in some assays. None of the viruses induced A. pisum to increase production of winged progeny, and aphids settled preferentially on leaf tissue from plants infected by all three viruses, the likely mechanism being visual responses to yellowing of foliage. Thus, in this system, the attractiveness of an infected host plant and its quality in terms of aphid growth and reproduction were not related to the pathogen's dependence on the aphid for transmission to new hosts. PMID:19161702

  11. Taux de reproduction du puceron du pois (Acyrthosiphon pisum Harris) et teneur en acide médicagénique de la luzerne (Medicago sativa L)

    OpenAIRE

    Bournoville, R

    1996-01-01

    Medicagenic acid, a major component of the saponin content of lucerne, has been reported by some authors as one of the possible mechanisms of resistance of lucerne to the pea aphid. We have measured the net reproductive rate of the pea aphid on 12 clones or hybrids of lucerne, derived from cultivars or lines of American (La, Res, Te) and French (12, 58, Eur) origins. The pea aphid performances were tested on plants growing under controlled conditions (temperature 20 °C, photophasis 16 h). Bef...

  12. Identification of Critical Conditions for Immunostaining in the Pea Aphid Embryos: Increasing Tissue Permeability and Decreasing Background Staining.

    Science.gov (United States)

    Lin, Gee-Way; Chang, Chun-che

    2016-01-01

    The pea aphid Acyrthosiphon pisum, with a sequenced genome and abundant phenotypic plasticity, has become an emerging model for genomic and developmental studies. Like other aphids, A. pisum propagate rapidly via parthenogenetic viviparous reproduction, where the embryos develop within egg chambers in an assembly-line fashion in the ovariole. Previously we have established a robust platform of whole-mount in situ hybridization allowing detection of mRNA expression in the aphid embryos. For analyzing the expression of protein, though, established protocols for immunostaining the ovarioles of asexual viviparous aphids did not produce satisfactory results. Here we report conditions optimized for increasing tissue permeability and decreasing background staining, both of which were problems when applying established approaches. Optimizations include: (1) incubation of proteinase K (1 µg/ml, 10 min), which was found essential for antibody penetration in mid- and late-stage aphid embryos; (2) replacement of normal goat serum/bovine serum albumin with a blocking reagent supplied by a Digoxigenin (DIG)-based buffer set and (3) application of methanol rather hydrogen peroxide (H2O2) for bleaching endogenous peroxidase; which significantly reduced the background staining in the aphid tissues. These critical conditions optimized for immunostaining will allow effective detection of gene products in the embryos of A. pisum and other aphids. PMID:26862939

  13. A simple wax-embedding method for isolation of aphid hemolymph for detection of luteoviruses in the hemocoel.

    Science.gov (United States)

    Liu, Sijun; Bonning, Bryony C; Allen Miller, W

    2006-03-01

    A protocol for isolating hemolymph from viruliferous aphids has been developed. This method uses warm melted wax to immobilize the aphid. Following removal of a hind leg, the hemolymph can be collected readily. Flushing with RNase-free water allows for collection of sufficient hemolymph for RNA extraction from individual aphids. The extracted RNA was successfully used for detection of barley yellow dwarf virus (BYDV) and pea enation mosaic virus (PEMV) from individual viruliferous Rhopalosiphum padi and Acyrthosiphon pisum aphids, respectively. A TaqMan real-time RT-PCR protocol for quantitation of PEMV in the hemolymph of individual aphids was developed. The wax-embedding hemolymph collection technique provides a useful tool for studying molecular interactions between persistent and circulative plant viruses and their insect vectors. PMID:16307802

  14. Dropping Behavior in the Pea Aphid (Hemiptera: Aphididae): How Does Environmental Context Affect Antipredator Responses?

    Science.gov (United States)

    Harrison, Katharine V; Preisser, Evan L

    2016-01-01

    The pea aphid Acyrthosiphon pisum : Harris (Hemiptera: Aphididae) is a phloem-feeding insect whose antipredator defenses include kicking, walking away, and dropping from the plant. Aphid dropping, a risky and energetically costly antipredator behavior, can be increased by the release of aphid alarm pheromone; there is also evidence that insect density and plant health can affect the likelihood of aphids engaging in this behavior. We investigated whether interactions between alarm cues, insect density, and plant health can alter the dropping behavior of aphids in response to an artificial disturbance. The presence of the alarm pheromone E-β-farnesene resulted in a nearly 15-fold increase in aphid dropping behavior; the other two factors, however, did not affect dropping and none of the two- or three-way interactions were significant. This was surprising because aphids affected plant health: production of new plant biomass after 5 d of exposure to high aphid densities was 50% lower than in the control treatment. This research adds to our understanding of the factors affecting aphid antipredator behavior; the fact that neither aphid density nor feeding period impacted dropping may reflect the high energetic costs of this activity and an unwillingness to use it in any but the riskiest situations. PMID:27638950

  15. Aphid salivary proteases are capable of degrading sieve-tube proteins.

    Science.gov (United States)

    Furch, Alexandra C U; van Bel, Aart J E; Will, Torsten

    2015-02-01

    Sieve tubes serve as transport conduits for photo-assimilates and other resources in angiosperms and are profitable targets for piercing-sucking insects such as aphids. Sieve-tube sap also contains significant amounts of proteins with diverse functions, for example in signalling, metabolism, and defence. The identification of salivary proteases in Acyrthosiphon pisum led to the hypothesis that aphids might be able to digest these proteins and by doing so suppress plant defence and access additional nitrogen sources. Here, the scarce knowledge of proteases in aphid saliva is briefly reviewed. In order to provide a better platform for discussion, we conducted a few tests on in vitro protease activity and degradation of sieve-tube sap proteins of Cucurbita maxima by watery saliva. Inhibition of protein degradation by EDTA indicates the presence of different types of proteases (e.g. metalloproteses) in saliva of A. pisum. Proteases in the watery saliva from Macrosiphum euphorbiae and A. pisum were able to degrade the most abundant phloem protein, which is phloem protein 1. Our results provide support for the breakdown of sieve-element proteins by aphid saliva in order to suppress/neutralize the defence responses of the plant and to make proteins of sieve-tube sap accessible as a nitrogen source, as is discussed in detail. Finally, we discuss whether glycosylation of sieve-element proteins and the presence of protease inhibitors may confer partial protection against the proteolytic activity of aphid saliva. PMID:25540441

  16. Winged Pea Aphids Can Modify Phototaxis in Different Development Stages to Assist Their Host Distribution.

    Science.gov (United States)

    Zhang, Yi; Wang, Xing-Xing; Jing, Xiangfeng; Tian, Hong-Gang; Liu, Tong-Xian

    2016-01-01

    The pea aphid, Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae), shows wing polyphenism (winged and wingless morphs) in its life cycle. The winged morph is adapted for dispersal; its two developmental adult stages (for dispersal and reproduction) are based on its breeding periods. The two morphs show different phototactic behavior and the winged can change its preference to light according to the developmental stages. To determine the mechanism and ecological functions of phototaxis for A. pisum, we first investigated the phototaxis of the two aphid morphs at different stages and analyzed the phototactic response to lights of different wavelengths; the correlation between alate fecundity and their phototactic behaviors were then studied. Finally, we focused on the possible functions of phototaxis in aphid host location and distribution in combination with gravitaxis behaviors. Negative phototaxis was found for breeding winged adults but all the other stages of both winged and wingless morphs showed positive phototaxis. The reactions of the aphids to different wavelengths were also different. Nymph production in winged adults showed negative correlation to phototaxis. The dopamine pathway was possibly involved in these behavior modifications. We speculated that winged adults can use light for dispersal in the early dispersal stage and for position holding in the breeding stage. Based on our results, we assume that light signals are important for aphid dispersal and distribution, and are also essential for the pea aphids to cope with environmental changes. PMID:27531980

  17. Enemy-free space promotes maintenance of host races in an aphid species.

    Science.gov (United States)

    Vosteen, Ilka; Gershenzon, Jonathan; Kunert, Grit

    2016-07-01

    The enormous biodiversity of herbivorous insects may arise from ecological speciation via continuous host-plant switches. Whether such switches are successful depends on the trade-off between different selection pressures that act on herbivores. Decreased herbivore performance due to suboptimal nutrition might be compensated for by a reduced natural enemy pressure. As a consequence, an "enemy-free space" on a certain plant might facilitate host-plant switches and maintain biotypes. To test this hypothesis, we used the pea aphid (Acyrthosiphon pisum) complex, which consists of at least 11 genetically distinct host races that are native to specific legume host plants but can all develop on the universal host plant Vicia faba. Three A. pisum host races native to Trifolium pratense, Pisum sativum, and Medicago sativa were investigated in experiments on their respective host plants and on the universal host plant V. faba. We found that hoverflies preferred to oviposit on P. sativum and the universal host V. faba. Since feeding by hoverfly larvae suppressed aphid population growth on these host plants, the native hosts M. sativa and T. pratense provided enemy-free space for the respective A. pisum races. Mobile predators, such as ants and ladybird beetles, preferred Pisum race aphids on V. faba over P. sativum. Thus, all three of the native host plants studied supply enemy-free space for A. pisum compared to the universal host V. faba. Reducing encounters between aphid races on V. faba would reduce gene flow among them and could contribute to maintaining the host races.

  18. Enemy-free space promotes maintenance of host races in an aphid species.

    Science.gov (United States)

    Vosteen, Ilka; Gershenzon, Jonathan; Kunert, Grit

    2016-07-01

    The enormous biodiversity of herbivorous insects may arise from ecological speciation via continuous host-plant switches. Whether such switches are successful depends on the trade-off between different selection pressures that act on herbivores. Decreased herbivore performance due to suboptimal nutrition might be compensated for by a reduced natural enemy pressure. As a consequence, an "enemy-free space" on a certain plant might facilitate host-plant switches and maintain biotypes. To test this hypothesis, we used the pea aphid (Acyrthosiphon pisum) complex, which consists of at least 11 genetically distinct host races that are native to specific legume host plants but can all develop on the universal host plant Vicia faba. Three A. pisum host races native to Trifolium pratense, Pisum sativum, and Medicago sativa were investigated in experiments on their respective host plants and on the universal host plant V. faba. We found that hoverflies preferred to oviposit on P. sativum and the universal host V. faba. Since feeding by hoverfly larvae suppressed aphid population growth on these host plants, the native hosts M. sativa and T. pratense provided enemy-free space for the respective A. pisum races. Mobile predators, such as ants and ladybird beetles, preferred Pisum race aphids on V. faba over P. sativum. Thus, all three of the native host plants studied supply enemy-free space for A. pisum compared to the universal host V. faba. Reducing encounters between aphid races on V. faba would reduce gene flow among them and could contribute to maintaining the host races. PMID:26520659

  19. Hoverfly preference for high honeydew amounts creates enemy-free space for aphids colonizing novel host plants.

    Science.gov (United States)

    Vosteen, Ilka; Gershenzon, Jonathan; Kunert, Grit

    2016-09-01

    The existence of an enemy-free space can play an important role in aphid host race formation processes, but little is known about the mechanisms that create an area of low predation pressure on particular host plants. In this paper, we identify a mechanism generating lower predation pressure that promotes the maintenance of the different host races of the pea aphid (Acyrthosiphon pisum) complex, a well-studied model for ecological speciation. The pea aphid consists of at least 15 genetically distinct host races which are native to specific host plants of the legume family, but can all develop on the universal host plant Vicia faba. Previous work showed that hoverfly (Episyrphus balteatus) oviposition preferences contribute to the enemy-free space that helps to maintain the different pea aphid host races, and that higher amounts of honeydew are more attractive to ovipositing hoverflies. Here we demonstrated that aphid honeydew is produced in large amounts when aphid reproduction rate was highest, and is an important oviposition cue for hoverflies under field conditions. However, on less suitable host plants, where honeydew production is reduced, pea aphids enjoy lower predation rates. A reduction in enemy pressure can mitigate the performance disadvantages of aphids colonizing a novel host and probably plays an important role in pea aphid host race formation. PMID:27328648

  20. Hoverfly preference for high honeydew amounts creates enemy-free space for aphids colonizing novel host plants.

    Science.gov (United States)

    Vosteen, Ilka; Gershenzon, Jonathan; Kunert, Grit

    2016-09-01

    The existence of an enemy-free space can play an important role in aphid host race formation processes, but little is known about the mechanisms that create an area of low predation pressure on particular host plants. In this paper, we identify a mechanism generating lower predation pressure that promotes the maintenance of the different host races of the pea aphid (Acyrthosiphon pisum) complex, a well-studied model for ecological speciation. The pea aphid consists of at least 15 genetically distinct host races which are native to specific host plants of the legume family, but can all develop on the universal host plant Vicia faba. Previous work showed that hoverfly (Episyrphus balteatus) oviposition preferences contribute to the enemy-free space that helps to maintain the different pea aphid host races, and that higher amounts of honeydew are more attractive to ovipositing hoverflies. Here we demonstrated that aphid honeydew is produced in large amounts when aphid reproduction rate was highest, and is an important oviposition cue for hoverflies under field conditions. However, on less suitable host plants, where honeydew production is reduced, pea aphids enjoy lower predation rates. A reduction in enemy pressure can mitigate the performance disadvantages of aphids colonizing a novel host and probably plays an important role in pea aphid host race formation.

  1. Aphid amino acid transporter regulates glutamine supply to intracellular bacterial symbionts.

    Science.gov (United States)

    Price, Daniel R G; Feng, Honglin; Baker, James D; Bavan, Selvan; Luetje, Charles W; Wilson, Alex C C

    2014-01-01

    Endosymbiotic associations have played a major role in evolution. However, the molecular basis for the biochemical interdependence of these associations remains poorly understood. The aphid-Buchnera endosymbiosis provides a powerful system to elucidate how these symbioses are regulated. In aphids, the supply of essential amino acids depends on an ancient nutritional symbiotic association with the gamma-proteobacterium Buchnera aphidicola. Buchnera cells are densely packed in specialized aphid bacteriocyte cells. Here we confirm that five putative amino acid transporters are highly expressed and/or highly enriched in Acyrthosiphon pisum bacteriocyte tissues. When expressed in Xenopus laevis oocytes, two bacteriocyte amino acid transporters displayed significant levels of glutamine uptake, with transporter ACYPI001018, LOC100159667 (named here as Acyrthosiphon pisum glutamine transporter 1, ApGLNT1) functioning as the most active glutamine transporter. Transporter ApGLNT1 has narrow substrate selectivity, with high glutamine and low arginine transport capacity. Notably, ApGLNT1 has high binding affinity for arginine, and arginine acts as a competitive inhibitor for glutamine transport. Using immunocytochemistry, we show that ApGLNT1 is localized predominantly to the bacteriocyte plasma membrane, a location consistent with the transport of glutamine from A. pisum hemolymph to the bacteriocyte cytoplasm. On the basis of functional transport data and localization, we propose a substrate feedback inhibition model in which the accumulation of the essential amino acid arginine in A. pisum hemolymph reduces the transport of the precursor glutamine into bacteriocytes, thereby regulating amino acid biosynthesis in the bacteriocyte. Structural similarities in the arrangement of hosts and symbionts across endosymbiotic systems suggest that substrate feedback inhibition may be mechanistically important in other endosymbioses.

  2. Aphid wing induction and ecological costs of alarm pheromone emission under field conditions.

    Directory of Open Access Journals (Sweden)

    Eduardo Hatano

    Full Text Available The pea aphid, Acyrthosiphon pisum Harris, (Homoptera: Aphididae releases the volatile sesquiterpene (E-beta-farnesene (EBF when attacked by a predator, triggering escape responses in the aphid colony. Recently, it was shown that this alarm pheromone also mediates the production of the winged dispersal morph under laboratory conditions. The present work tested the wing-inducing effect of EBF under field conditions. Aphid colonies were exposed to two treatments (control and EBF and tested in two different environmental conditions (field and laboratory. As in previous experiments aphids produced higher proportion of winged morphs among their offspring when exposed to EBF in the laboratory but even under field conditions the proportion of winged offspring was higher after EBF application (6.84+/-0.98% compared to the hexane control (1.54+/-0.25%. In the field, the proportion of adult aphids found on the plant at the end of the experiment was lower in the EBF treatment (58.1+/-5.5% than in the control (66.9+/-4.6%, in contrast to the climate chamber test where the numbers of adult aphids found on the plant at the end of the experiment were, in both treatments, similar to the numbers put on the plant initially. Our results show that the role of EBF in aphid wing induction is also apparent under field conditions and they may indicate a potential cost of EBF emission. They also emphasize the importance of investigating the ecological role of induced defences under field conditions.

  3. To feed or not to feed: plant factors located in the epidermis, mesophyll, and sieve elements influence pea aphid's ability to feed on legume species.

    Directory of Open Access Journals (Sweden)

    Alexander Schwarzkopf

    Full Text Available The pea aphid (Acyrthosiphon pisum Harris, a legume specialist, encompasses at least 11 genetically distinct sympatric host races. Each host race shows a preference for a certain legume species. Six pea aphid clones from three host races were used to localize plant factors influencing aphid probing and feeding behavior on four legume species. Aphid performance was tested by measuring survival and growth. The location of plant factors influencing aphid probing and feeding was determined using the electrical penetration graph (EPG technique. Every aphid clone performed best on the plant species from which it was originally collected, as well as on Vicia faba. On other plant species, clones showed intermediate or poor performance. The most important plant factors influencing aphid probing and feeding behavior were localized in the epidermis and sieve elements. Repetitive puncturing of sieve elements might be relevant for establishing phloem feeding, since feeding periods appear nearly exclusively after these repetitive sieve element punctures. A combination of plant factors influences the behavior of pea aphid host races on different legume species and likely contributes to the maintenance of these races.

  4. Pea aphid promotes amino acid metabolism both in Medicago truncatula and bacteriocytes to favor aphid population growth under elevated CO2.

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    Guo, Huijuan; Sun, Yucheng; Li, Yuefei; Tong, Bin; Harris, Marvin; Zhu-Salzman, Keyan; Ge, Feng

    2013-10-01

    Rising atmospheric CO(2) levels can dilute the nitrogen (N) resource in plant tissue, which is disadvantageous to many herbivorous insects. Aphids appear to be an exception that warrants further study. The effects of elevated CO(2) (750 ppm vs. 390 ppm) were evaluated on N assimilation and transamination by two Medicago truncatula genotypes, a N-fixing-deficient mutant (dnf1) and its wild-type control (Jemalong), with and without pea aphid (Acyrthosiphon pisum) infestation. Elevated CO(2) increased population abundance and feeding efficiency of aphids fed on Jemalong, but reduced those on dnf1. Without aphid infestation, elevated CO(2) increased photosynthetic rate, chlorophyll content, nodule number, biomass, and pod number for Jemalong, but only increased pod number and chlorophyll content for dnf1. Furthermore, aphid infested Jemalong plants had enhanced activities of N assimilation-related enzymes (glutamine synthetase, Glutamate synthase) and transamination-related enzymes (glutamate oxalate transaminase, glutamine phenylpyruvate transaminase), which presumably increased amino acid concentration in leaves and phloem sap under elevated CO(2). In contrast, aphid infested dnf1 plants had decreased activities of N assimilation-related enzymes and transmination-related enzymes and amino acid concentrations under elevated CO(2). Furthermore, elevated CO(2) up-regulated expression of genes relevant to amino acid metabolism in bacteriocytes of aphids associated with Jemalong, but down-regulated those associated with dnf1. Our results suggest that pea aphids actively elicit host responses that promote amino acid metabolism in both the host plant and in its bacteriocytes to favor the population growth of the aphid under elevated CO(2).

  5. Elevated CO2 decreases the response of the ethylene signaling pathway in Medicago truncatula and increases the abundance of the pea aphid.

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    Guo, Huijuan; Sun, Yucheng; Li, Yuefei; Liu, Xianghui; Zhang, Wenhao; Ge, Feng

    2014-01-01

    The performance of herbivorous insects is greatly affected by plant nutritional quality and resistance, which are likely to be altered by rising concentrations of atmospheric CO2 . We previously reported that elevated CO2 enhanced biological nitrogen (N) fixation of Medicago truncatula, which could result in an increased supply of amino acids to the pea aphid (Acyrthosiphon pisum). The current study examined the N nutritional quality and aphid resistance of sickle, an ethylene-insensitive mutant of M. truncatula with supernodulation, and its wild-type control A17 under elevated CO2 in open-top field chambers. Regardless of CO2 concentration, growth and amino acid content were greater and aphid resistance was lower in sickle than in A17. Elevated CO2 up-regulated N assimilation and transamination-related enzymes activities and increased phloem amino acids in both genotypes. Furthermore, elevated CO2 down-regulated expression of 1-amino-cyclopropane-carboxylic acid (ACC), sickle gene (SKL) and ethylene response transcription factors (ERF) genes in the ethylene signaling pathway of A17 when infested by aphids and decreased resistance against aphids in terms of lower activities of superoxide dismutase (SOD), peroxidase (POD), and polyphenol oxidase (PPO). Our results suggest that elevated CO2 suppresses the ethylene signaling pathway in M. truncatula, which results in an increase in plant nutritional quality for aphids and a decrease in plant resistance against aphids.

  6. Transcriptome Analysis of Green Peach Aphid (Myzus persicae): Insight into Developmental Regulation and Inter-Species Divergence

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    Ji, Rui; Wang, Yujun; Cheng, Yanbin; Zhang, Meiping; Zhang, Hong-Bin; Zhu, Li; Fang, Jichao; Zhu-Salzman, Keyan

    2016-01-01

    Green peach aphid (Myzus persicae) and pea aphid (Acyrthosiphon pisum) are two phylogenetically closely related agricultural pests. While pea aphid is restricted to Fabaceae, green peach aphid feeds on hundreds of plant species from more than 40 families. Transcriptome comparison could shed light on the genetic factors underlying the difference in host range between the two species. Furthermore, a large scale study contrasting gene expression between immature nymphs and fully developed adult aphids would fill a previous knowledge gap. Here, we obtained transcriptomic sequences of green peach aphid nymphs and adults, respectively, using Illumina sequencing technology. A total of 2244 genes were found to be differentially expressed between the two developmental stages, many of which were associated with detoxification, hormone production, cuticle formation, metabolism, food digestion, and absorption. When searched against publically available pea aphid mRNA sequences, 13,752 unigenes were found to have no homologous counterparts. Interestingly, many of these unigenes that could be annotated in other databases were involved in the “xenobiotics biodegradation and metabolism” pathway, suggesting the two aphids differ in their adaptation to secondary metabolites of host plants. Conversely, 3989 orthologous gene pairs between the two species were subjected to calculations of synonymous and nonsynonymous substitutions, and 148 of the genes potentially evolved in response to positive selection. Some of these genes were predicted to be associated with insect-plant interactions. Our study has revealed certain molecular events related to aphid development, and provided some insight into biological variations in two aphid species, possibly as a result of host plant adaptation.

  7. Transcriptomic and proteomic analyses of seasonal photoperiodism in the pea aphid

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    Gauthier J-P

    2009-09-01

    Full Text Available Abstract Background Aphid adaptation to harsh winter conditions is illustrated by an alternation of their reproductive mode. Aphids detect photoperiod shortening by sensing the length of the night and switch from viviparous parthenogenesis in spring and summer, to oviparous sexual reproduction in autumn. The photoperiodic signal is transduced from the head to the reproductive tract to change the fate of the future oocytes from mitotic diploid embryogenesis to haploid formation of gametes. This process takes place in three consecutive generations due to viviparous parthenogenesis. To understand the molecular basis of the switch in the reproductive mode, transcriptomic and proteomic approaches were used to detect significantly regulated transcripts and polypeptides in the heads of the pea aphid Acyrthosiphon pisum. Results The transcriptomic profiles of the heads of the first generation were slightly affected by photoperiod shortening. This suggests that trans-generation signalling between the grand-mothers and the viviparous embryos they contain is not essential. By analogy, many of the genes and some of the proteins regulated in the heads of the second generation are implicated in visual functions, photoreception and cuticle structure. The modification of the cuticle could be accompanied by a down-regulation of the N-β-alanyldopamine pathway and desclerotization. In Drosophila, modification of the insulin pathway could cause a decrease of juvenile hormones in short-day reared aphids. Conclusion This work led to the construction of hypotheses for photoperiodic regulation of the switch of the reproductive mode in aphids.

  8. Serratia symbiotica from the aphid Cinara cedri: a missing link from facultative to obligate insect endosymbiont.

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    Araceli Lamelas

    2011-11-01

    Full Text Available The genome sequencing of Buchnera aphidicola BCc from the aphid Cinara cedri, which is the smallest known Buchnera genome, revealed that this bacterium had lost its symbiotic role, as it was not able to synthesize tryptophan and riboflavin. Moreover, the biosynthesis of tryptophan is shared with the endosymbiont Serratia symbiotica SCc, which coexists with B. aphidicola in this aphid. The whole-genome sequencing of S. symbiotica SCc reveals an endosymbiont in a stage of genome reduction that is closer to an obligate endosymbiont, such as B. aphidicola from Acyrthosiphon pisum, than to another S. symbiotica, which is a facultative endosymbiont in this aphid, and presents much less gene decay. The comparison between both S. symbiotica enables us to propose an evolutionary scenario of the transition from facultative to obligate endosymbiont. Metabolic inferences of B. aphidicola BCc and S. symbiotica SCc reveal that most of the functions carried out by B. aphidicola in A. pisum are now either conserved in B. aphidicola BCc or taken over by S. symbiotica. In addition, there are several cases of metabolic complementation giving functional stability to the whole consortium and evolutionary preservation of the actors involved.

  9. Proton-dependent glutamine uptake by aphid bacteriocyte amino acid transporter ApGLNT1.

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    Price, Daniel R G; Wilson, Alex C C; Luetje, Charles W

    2015-10-01

    Aphids house large populations of the gammaproteobacterial symbiont Buchnera aphidicola in specialized bacteriocyte cells. The combined biosynthetic capability of the holobiont (Acyrthosiphon pisum and Buchnera) is sufficient for biosynthesis of all twenty protein coding amino acids, including amino acids that animals alone cannot synthesize; and that are present at low concentrations in A. pisum's plant phloem sap diet. Collaborative holobiont amino acid biosynthesis depends on glutamine import into bacteriocytes, which serves as a nitrogen-rich amino donor for biosynthesis of other amino acids. Recently, we characterized A. pisum glutamine transporter 1 (ApGLNT1), a member of the amino acid/auxin permease family, as the dominant bacteriocyte plasma membrane glutamine transporter. Here we show ApGLNT1 to be structurally and functionally related to mammalian proton-dependent amino acid transporters (PATs 1-4). Using functional expression in Xenopus laevis oocytes, combined with two-electrode voltage clamp electrophysiology we demonstrate that ApGLNT1 is electrogenic and that glutamine induces large inward currents. ApGLNT1 glutamine induced currents are dependent on external glutamine concentration, proton (H+) gradient across the membrane, and membrane potential. Based on these transport properties, ApGLNT1-mediated glutamine uptake into A. pisum bacteriocytes can be regulated by changes in either proton gradients across the plasma membrane or membrane potential. PMID:26028424

  10. Insulin-related peptide 5 is involved in regulating embryo development and biochemical composition in pea aphid with wing polyphenism

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    Shan-Shan eGuo

    2016-02-01

    Full Text Available In aphids there is a fecundity-dispersal trade-off between wingless and winged morphs. Recent research on the molecular mechanism of wing morphs associated with dispersal reveals that insulin receptors in the insulin signaling (IS pathway regulate alteration of wing morphs in planthoppers. However, little is known about whether genes in the IS pathway are involved in developmental regulation in aphid nymphs with different wing morphs. In this study, we show that expression of the insulin-related peptide 5 gene (Apirp5 affects biochemical composition and embryo development of wingless pea aphids, Acyrthosiphon pisum. After comparing expression levels of major genes in the IS pathway between third instar winged and wingless nymphs, we found that Apirp5 showed higher expression in head and thorax of the wingless nymphs than in the winged nymphs. Although microinjection treatment affects physical performance in aphids, nymphs with RNA interference of Apirp5 had less weight, smaller embryo size and higher carbohydrate and protein contents compared to control group. Comparison between winged and wingless nymphs showed a similar trend. These results indicate that Apirp5 is involved in embryo development and metabolic regulation in wing dimorphic pea aphid.

  11. Dropping behaviour of pea aphid nymphs increases their development time and reduces their reproductive capacity as adults.

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    Agabiti, Barbara; Wassenaar, Roxanne J; Winder, Linton

    2016-01-01

    Background. Many aphid species, including the pea aphid Acyrthosiphon pisum, exhibit a behaviour where they drop or fall from their host plant, a commonly used strategy to avoid predation, parasitism or physical disturbance. We hypothesised that there was a physiological non-consumptive cost due to such dropping behaviour because aphids would expend energy re-establishing themselves on a host plant and also lose feeding time. Methods. We evaluated this non-consumptive cost by determining the development time and reproductive potential of pea aphids that whilst developing as nymphs had regularly dropped to the ground following dislodgment from their host plant. Using a microcosm approach, in a replicated and balanced laboratory experiment, we caused aphid dropping behaviour by tapping the plants on which they were feeding. Results. The results demonstrated that disturbance by dropping behaviour increased nymphal development time and reduced their subsequent reproductive capacity as adults. Discussion. We conclude that dropping behaviour had a strong negative effect on the development of nymphs and their subsequent reproductive capacity. This implies that the physiological cost of such a behaviour choice is substantial, and that such avoidance strategies require a trade-off which reduces the capacity of a population to increase. PMID:27547545

  12. Using the pea aphid Acrythociphon pisum as a tool for screening biological responses to chemicals and drugs

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    Ledger Terence

    2009-09-01

    Full Text Available Abstract Background Though the biological process of aphid feeding is well documented, no one to date has sought to apply it as a tool to screen the biological responses to chemicals and drugs, in ecotoxicology, genotoxicology and/or for interactions in the cascade of sequential molecular events of embryogenesis. Parthenogenetic insect species present the advantage of an anatomical system composed of multiple germarium/ovarioles in the same mother with all the intermediate maturation stages of embryos from oocyte to first instar larva birth. This could be used as an interesting model to visualize at which step drugs interact with the cell signalling pathway during the ordered developmental process. Findings We designed a simple test for screening drugs by investigating simultaneously zygote mitotic division, the progression of embryo development, cell differentiation at early developmental stages and finally organogenesis and population growth rate. We aimed to analyze the toxicology effects of compounds and/or their interference on cellular signalling by examining at which step of the cascade, from zygote to mature embryo, the developmental process is perturbed. We reasoned that a parthenogenetic founder insect, in which the ovarioles shelter numerous embryos at different developmental stages, would allow us to precisely pinpoint the step of embryogenesis in which chemicals act through specific molecular targets as the known ordered homeobox genes. Conclusion Using this method we report the results of a genotoxicological and demographic analysis of three compound models bearing in common a bromo group: one is integrated as a base analog in DNA synthesis, two others activate permanently kinases. We report that one compound (Br-du altered drastically embryogenesis, which argues in favor of this simple technique as a cheap first screening of chemicals or drugs to be used in a number of genotoxicology applications.

  13. Aphid thermal tolerance is governed by a point mutation in bacterial symbionts.

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    Helen E Dunbar

    2007-05-01

    Full Text Available Symbiosis is a ubiquitous phenomenon generating biological complexity, affecting adaptation, and expanding ecological capabilities. However, symbionts, which can be subject to genetic limitations such as clonality and genomic degradation, also impose constraints on hosts. A model of obligate symbiosis is that between aphids and the bacterium Buchnera aphidicola, which supplies essential nutrients. We report a mutation in Buchnera of the aphid Acyrthosiphon pisum that recurs in laboratory lines and occurs in field populations. This single nucleotide deletion affects a homopolymeric run within the heat-shock transcriptional promoter for ibpA, encoding a small heat-shock protein. This Buchnera mutation virtually eliminates the transcriptional response of ibpA to heat stress and lowers its expression even at cool or moderate temperatures. Furthermore, this symbiont mutation dramatically affects host fitness in a manner dependent on thermal environment. Following a short heat exposure as juveniles, aphids bearing short-allele symbionts produced few or no progeny and contained almost no Buchnera, in contrast to aphids bearing symbionts without the deletion. Conversely, under constant cool conditions, aphids containing symbionts with the short allele reproduced earlier and maintained higher reproductive rates. The short allele has appreciable frequencies in field populations (up to 20%, further supporting the view that lowering of ibpA expression improves host fitness under some conditions. This recurring Buchnera mutation governs thermal tolerance of aphid hosts. Other cases in which symbiont microevolution has a major effect on host ecological tolerance are likely to be widespread because of the high mutation rates of symbiotic bacteria and their crucial roles in host metabolism and development.

  14. Differential gene expression according to race and host plant in the pea aphid.

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    Eyres, Isobel; Jaquiéry, Julie; Sugio, Akiko; Duvaux, Ludovic; Gharbi, Karim; Zhou, Jing-Jiang; Legeai, Fabrice; Nelson, Michaela; Simon, Jean-Christophe; Smadja, Carole M; Butlin, Roger; Ferrari, Julia

    2016-09-01

    Host-race formation in phytophagous insects is thought to provide the opportunity for local adaptation and subsequent ecological speciation. Studying gene expression differences amongst host races may help to identify phenotypes under (or resulting from) divergent selection and their genetic, molecular and physiological bases. The pea aphid (Acyrthosiphon pisum) comprises host races specializing on numerous plants in the Fabaceae and provides a unique system for examining the early stages of diversification along a gradient of genetic and associated adaptive divergence. In this study, we examine transcriptome-wide gene expression both in response to environment and across pea aphid races selected to cover the range of genetic divergence reported in this species complex. We identify changes in expression in response to host plant, indicating the importance of gene expression in aphid-plant interactions. Races can be distinguished on the basis of gene expression, and higher numbers of differentially expressed genes are apparent between more divergent races; these expression differences between host races may result from genetic drift and reproductive isolation and possibly divergent selection. Expression differences related to plant adaptation include a subset of chemosensory and salivary genes. Genes showing expression changes in response to host plant do not make up a large portion of between-race expression differences, providing confirmation of previous studies' findings that genes involved in expression differences between diverging populations or species are not necessarily those showing initial plasticity in the face of environmental change. PMID:27474484

  15. Circulative Nonpropagative Aphid Transmission of Nanoviruses: an Oversimplified View

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    Sicard, Anne; Zeddam, Jean-Louis; Yvon, Michel; Michalakis, Yannis; Gutiérrez, Serafin

    2015-01-01

    ABSTRACT Plant virus species of the family Nanoviridae have segmented genomes with the highest known number of segments encapsidated individually. They thus likely represent the most extreme case of the so-called multipartite, or multicomponent, viruses. All species of the family are believed to be transmitted in a circulative nonpropagative manner by aphid vectors, meaning that the virus simply crosses cellular barriers within the aphid body, from the gut to the salivary glands, without replicating or even expressing any of its genes. However, this assumption is largely based on analogy with the transmission of other plant viruses, such as geminiviruses or luteoviruses, and the details of the molecular and cellular interactions between aphids and nanoviruses are poorly investigated. When comparing the relative frequencies of the eight genome segments in populations of the species Faba bean necrotic stunt virus (FBNSV) (genus Nanovirus) within host plants and within aphid vectors fed on these plants, we unexpectedly found evidence of reproducible changes in the frequencies of some specific segments. We further show that these changes occur within the gut during early stages of the virus cycle in the aphid and not later, when the virus is translocated into the salivary glands. This peculiar observation, which was similarly confirmed in three aphid vector species, Acyrthosiphon pisum, Aphis craccivora, and Myzus persicae, calls for revisiting of the mechanisms of nanovirus transmission. It reveals an unexpected intimate interaction that may not fit the canonical circulative nonpropagative transmission. IMPORTANCE A specific mode of interaction between viruses and arthropod vectors has been extensively described in plant viruses in the three families Luteoviridae, Geminiviridae, and Nanoviridae, but never in arboviruses of animals. This so-called circulative nonpropagative transmission contrasts with the classical biological transmission of animal arboviruses in that

  16. Seasonal Changes in the Endosymbiotic Consortia of Aphids from the Genus Cinara

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    Martínez-Díaz, Vanesa; Latorre, Amparo; Gil, Rosario

    2016-01-01

    Buchnera aphidicola is the primary endosymbiont of aphids with which it maintains an obligate mutualistic symbiotic relationship. Insects also maintain facultative symbiotic relationships with secondary symbionts, and Serratia symbiotica is the most common in aphids. The presence of both symbionts in aphids of the subfamily Lachninae has been widely studied by our group. We examined two closely related aphids, Cinara tujafilina and C. cedri in the present study. Even though both B. aphidicola strains have similar genome sizes and gene contents, the genomes of the two S. symbiotica strains were markedly different. The SCc strain has the smallest genome known for this species, while SCt possesses a larger genome in an intermediate stage between the facultative S. symbiotica of Acyrthosiphon pisum (SAp) and the co-obligate S. symbiotica SCc. Aphids are vulnerable to high temperatures. Previous studies indicated that S. symbiotica SAp confers resistance to heat-shock stress. In order to clarify whether S. symbiotica strains from genus Cinara also play a role in heat stress protection, we performed a quantitative determination of the consortium Buchnera/Serratia from two geographically close populations, each of which belonged to the Cinara species examined, over two years in natural environments. We found no variation in the consortium from our C. cedri population, but a positive correlation between both endosymbiont densities and average daily temperatures in the C. tujafilina population. Even though S. symbiotica SCt may retain some protective role against heat stress, this does not appear to be due to the release of protective metabolites by cell lysis. PMID:27297891

  17. Increasing phosphorus supply is not the mechanism by which arbuscular mycorrhiza increase attractiveness of bean (Vicia faba) to aphids

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    Babikova, Zdenka; Gilbert, Lucy; Randall, Kate C.; Bruce, Toby J. A.; Pickett, John A.; Johnson, David

    2014-01-01

    Arbuscular mycorrhizal (AM) fungi, important plant mutualists, provide plants with nutrients such as phosphorus (P) in return for carbon. AM fungi also enhance the attractiveness of plants to aphids via effects on emissions of plant volatiles used in aphid host location. We tested whether increased P uptake by plants is the mechanism through which AM fungi alter the volatile profile of plants and aphid behavioural responses by manipulating the availability of P and AM fungi to broad beans (Vicia faba L.) in a multi-factorial design. If AM fungi affect plant volatiles only via increased P acquisition, we predicted that the emission of volatiles and the attractiveness of mycorrhizal beans to aphids would be similar to those of non-mycorrhizal beans supplied with additional P. AM fungi and P addition increased leaf P concentrations by 40 and 24%, respectively. The production of naphthalene was less in mycorrhizal plants, regardless of P addition. By contrast, production of (S)-linalool, (E)-caryophyllene and (R)-germacrene D was less in plants colonized by AM fungi but only in the absence of P additions. The attractiveness of plants to pea aphids (Acyrthosiphon pisum Harris) was positively affected by AM fungi and correlated with the extent of root colonization; however, attractiveness was neither affected by P treatment nor correlated with leaf P concentration. These findings suggest that increased P uptake is not the main mechanism by which mycorrhiza increase the attractiveness of plants to aphids. Instead, the mechanism is likely to operate via AM fungi-induced plant systemic signalling. PMID:25200735

  18. Young aphids avoid erroneous dropping when evading mammalian herbivores by combining input from two sensory modalities.

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    Moshe Gish

    Full Text Available Mammalian herbivores may incidentally ingest plant-dwelling insects while foraging. Adult pea aphids (Acyrthosiphon pisum avoid this danger by dropping off their host plant after sensing the herbivore's warm and humid breath and the vibrations it causes while feeding. Aphid nymphs may also drop (to escape insect enemies, but because of their slow movement, have a lower chance of finding a new plant. We compared dropping rates of first-instar nymphs with those of adults, after exposing pea aphids to different combinations of simulated mammalian breath and vibrations. We hypothesized that nymphs would compensate for the greater risk they face on the ground by interpreting more conservatively the mammalian herbivore cues they perceive. Most adults dropped in response to breath alone, but nymphs rarely did so. Breath stimulus accompanied by one concurrent vibrational stimulus, caused a minor rise in adult dropping rates. Adding a second vibration during breath had no additional effect on adults. The nymphs, however, relied on a combination of the two types of stimuli, with a threefold increase in dropping rates when the breath was accompanied by one vibration, and a further doubling of dropping rates when the second vibration was added. The age-specificity of the aphids' herbivore detection mechanism is probably an adaptation to the different cost of dropping for the different age groups. Relying on a combination of stimuli from two sensory modalities enables the vulnerable nymphs to avoid costly mistakes. Our findings emphasize the importance of the direct trophic effect of mammalian herbivory for plant-dwelling insects.

  19. Glucosinolates from Host Plants Influence Growth of the Parasitic Plant Cuscuta gronovii and Its Susceptibility to Aphid Feeding.

    Science.gov (United States)

    Smith, Jason D; Woldemariam, Melkamu G; Mescher, Mark C; Jander, Georg; De Moraes, Consuelo M

    2016-09-01

    Parasitic plants acquire diverse secondary metabolites from their hosts, including defense compounds that target insect herbivores. However, the ecological implications of this phenomenon, including the potential enhancement of parasite defenses, remain largely unexplored. We studied the translocation of glucosinolates from the brassicaceous host plant Arabidopsis (Arabidopsis thaliana) into parasitic dodder vines (Convolvulaceae; Cuscuta gronovii) and its effects on the parasite itself and on dodder-aphid interactions. Aliphatic and indole glucosinolates reached concentrations in parasite tissues higher than those observed in corresponding host tissues. Dodder growth was enhanced on cyp79B2 cyp79B3 hosts (without indole glucosinolates) but inhibited on atr1D hosts (with elevated indole glucosinolates) relative to wild-type hosts, which responded to parasitism with localized elevation of indole and aliphatic glucosinolates. These findings implicate indole glucosinolates in defense against parasitic plants. Rates of settling and survival on dodder vines by pea aphids (Acyrthosiphon pisum) were reduced significantly when dodder parasitized glucosinolate-producing hosts (wild type and atr1D) compared with glucosinolate-free hosts (cyp79B2 cyp79B3 myb28 myb29). However, settling and survival of green peach aphids (Myzus persicae) were not affected. M. persicae population growth was actually reduced on dodder parasitizing glucosinolate-free hosts compared with wild-type or atr1D hosts, even though stems of the former contain less glucosinolates and more amino acids. Strikingly, this effect was reversed when the aphids fed directly upon Arabidopsis, which indicates an interactive effect of parasite and host genotype on M. persicae that stems from host effects on dodder. Thus, our findings indicate that glucosinolates may have both direct and indirect effects on dodder-feeding herbivores. PMID:27482077

  20. Abundancia y riqueza específica de pulgones (Hemiptera: Aphididae y sus parasitoides en diferentes genotipos y estados fenologicos del garbanzo Species richness and abundance of aphids (Hemiptera: Aphididae and their parasitoids in different genotypes and at different growth stages of chickpea

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    V. E. Mazzuferi

    2011-12-01

    Full Text Available Los áfidos son insectos perjudiciales tanto por la succión de savia como por la transmisión de enfermedades. Los objetivos de este trabajo fueron conocer las especies de áfidos y sus parasitoides presentes en diferentes genotipos de garbanzo, calcular la incidencia del parasitismo e informar sobre las fluctuaciones poblacionales de pulgones y parasitoides en relación a los estados fenológicos del cultivo. El estudio se realizó durante 2006 y 2007 en San Marcos Sierras (Córdoba. Se evaluaron siete líneas y dos cultivares sembrados en un diseño en bloques completamente aleatorizados con tres repeticiones. Cada 15 días se colectaron manualmente áfidos y "momias" presentes en 10 plantas seleccionadas al azar, de cada genotipo y bloque. Se determinaron 13 especies de áfidos. En 2006 se observó mayor abundancia y riqueza de especies que en 2007. Las especies numéricamente dominantes fueron: Acyrthosiphon pisum y A. kondoi. Solamente cinco especies colonizaron el cultivo. El cultivar Chañaritos presentó la mayor abundancia de insectos en los dos años agrícolas, y los genotipos M60 y M75 mostraron la mayor riqueza de especies. En ambos años, los pulgones estuvieron presentes durante la etapa reproductiva del cultivo. Se registraron tres especies de parasitoides y se estimó un 35% de parasitismo total.Aphids may damage plants by sucking plant juices or by transmitting diseases. The aim of this study was to obtain further information about aphid species and their parasitoids in different genotypes of chickpea, calculate the incidence of parasitism and report on fluctuating populations (from aphids and parasitoid in relation to plant phenology. The study was undertaken during 2006 and 2007 in San Marcos Sierras (Cordoba. Seven lines and two cultivars of chickpea were evaluated. Crop plots were planted following a completely randomized design block with 3 replicates. Every two weeks different developmental stages of aphids and "mummies

  1. Developmental origin and evolution of bacteriocytes in the aphid-Buchnera symbiosis.

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    Christian Braendle

    2003-10-01

    Full Text Available Symbiotic relationships between bacteria and insect hosts are common. Although the bacterial endosymbionts have been subjected to intense investigation, little is known of the host cells in which they reside, the bacteriocytes. We have studied the development and evolution of aphid bacteriocytes, the host cells that contain the endosymbiotic bacteria Buchnera aphidicola. We show that bacteriocytes of Acyrthosiphon pisum express several gene products (or their paralogues: Distal-less, Ultrabithorax/Abdominal-A, and Engrailed. Using these markers, we find that a subpopulation of the bacteriocytes is specified prior to the transmission of maternal bacteria to the embryo. In addition, we discovered that a second population of cells is recruited to the bacteriocyte fate later in development. We experimentally demonstrate that bacteriocyte induction and proliferation occur independently of B. aphidicola. Major features of bacteriocyte development, including the two-step recruitment of bacteriocytes, have been conserved in aphids for 80-150 million years. Furthermore, we have investigated two cases of evolutionary loss of bacterial symbionts: in one case, where novel extracellular, eukaryotic symbionts replaced the bacteria, the bacteriocyte is maintained; in another case, where symbionts are absent, the bacteriocytes are initiated but not maintained. The bacteriocyte represents an evolutionarily novel cell fate, which is developmentally determined independently of the bacteria. Three of five transcription factors we examined show novel expression patterns in bacteriocytes, suggesting that bacteriocytes may have evolved to express many additional transcription factors. The evolutionary transition to a symbiosis in which bacteria and an aphid cell form a functional unit, similar to the origin of plastids, has apparently involved extensive molecular adaptations on the part of the host cell.

  2. Monitoring of aphid flight activities in seed potato crops in Serbia.

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    Vučetić, Andja; Vukov, Tanja; Jovičić, Ivana; Petrović-Obradović, Olivera

    2013-01-01

    Aphid flight activities in seed potato fields have been studied by the yellow water traps. It is a good method for monitoring aphids as vectors of viruses, but this study also showed it is a suitable method for insect-diversity research. During the four-year studies, over 11.500 specimens were collected and a total of 107 different taxa of aphids were identified. The most abundant species were polyphagous species, such as: Acyrthosiphon pisum (Haris), Aphis fabae Scopoli, Aphis gossypii Gloverand Brachycaudus helichrysi (Kaltenbach). The results of the studies show that diversity of aphids in different regions of Serbia is similar regardless of the altitude and the diversity of terrain. At most sites it ranged from 2 to 3. The highest value was recorded in Begeč, locality in northern part of Serbia, in year 2008, and it was 2.92. The maximum values of the Shannon-Weaver diversity index at all sites were recorded in the first weeks of the monitoring of aphid flight activities. Morisita-Horn similarity index shows no significant differences between sites regardless of altitudes. The sites are grouped by year, not by similarity of relief. In spite of these results, the Chi-square analysis showed highly significant difference in vector frequencies among seasons and sites with more pronounced differences for PVY. As a consequence of differences in vector frequencies, the vector pressure index in some regions was different also. The number of vectors and vector pressure index vary depending on the altitude of localities. At localities at altitudes under 1000 m, they were high. The highest index was at Kotraža, locality in central part of Serbia, in 2007, when PVY index exceeded the value of 180, while for PLRV it was 60. At high altitudes on mountain Golija, above 1100 m, the number of aphids was low, as well as the vector pressure index which indicates that these regions are suitable for producing virus-free seed potato. PMID:24039529

  3. Monitoring of aphid flight activities in seed potato crops in Serbia

    Directory of Open Access Journals (Sweden)

    Andja Vucetic

    2013-07-01

    Full Text Available Aphid flight activities in seed potato fields have been studied by the yellow water traps. It is a good method for monitoring aphids as vectors of viruses, but this study also showed it is a suitable method for insect-diversity research. During the four-year studies, over 11.500 specimens were collected and a total of 107 different taxa of aphids were identified. The most abundant species were polyphagous species, such as: Acyrthosiphon pisum (Haris, Aphis fabae Scopoli, Aphis gossypii Glover and Brachycaudus helichrysi (Kaltenbach. The results of the studies show that diversity of aphids in different regions of Serbia is similar regardless of the altitude and the diversity of terrain. At most sites it ranged from 2 to 3. The highest value was recorded in Begeč, locality in northern part of Serbia, in year 2008, and it was 2.92. The maximum values of the Shannon-Weaver diversity index at all sites were recorded in the first weeks of the monitoring of aphid flight activities. Morisita-Horn similarity index shows no significant differences between sites regardless of altitudes. The sites are grouped by year, not by similarity of relief. In spite of these results, the Chi-square analysis showed highly significant difference in vector frequencies among seasons and sites with more pronounced differences for PVY. As a consequence of differences in vector frequencies, the vector pressure index in some regions was different also. The number of vectors and vector pressure index vary depending on the altitude of localities. At localities at altitudes under 1000 m, they were high. The highest index was at Kotraža, locality in central part of Serbia, in 2007, when PVY index exceeded the value of 180, while for PLRV it was 60. At high altitudes on mountain Golija, above 1100 m, the number of aphids was low, as well as the vector pressure index which indicates that these regions are suitable for producing virus-free seed potato.

  4. A genomic reappraisal of symbiotic function in the aphid/Buchnera symbiosis: reduced transporter sets and variable membrane organisations.

    Directory of Open Access Journals (Sweden)

    Hubert Charles

    Full Text Available Buchnera aphidicola is an obligate symbiotic bacterium that sustains the physiology of aphids by complementing their exclusive phloem sap diet. In this study, we reappraised the transport function of different Buchnera strains, from the aphids Acyrthosiphon pisum, Schizaphis graminum, Baizongia pistaciae and Cinara cedri, using the re-annotation of their transmembrane proteins coupled with an exploration of their metabolic networks. Although metabolic analyses revealed high interdependencies between the host and the bacteria, we demonstrate here that transport in Buchnera is assured by low transporter diversity, when compared to free-living bacteria, being mostly based on a few general transporters, some of which probably have lost their substrate specificity. Moreover, in the four strains studied, an astonishing lack of inner-membrane importers was observed. In Buchnera, the transport function has been shaped by the distinct selective constraints occurring in the Aphididae lineages. Buchnera from A. pisum and S. graminum have a three-membraned system and similar sets of transporters corresponding to most compound classes. Transmission electronic microscopic observations and confocal microscopic analysis of intracellular pH fields revealed that Buchnera does not show any of the typical structures and properties observed in integrated organelles. Buchnera from B. pistaciae seem to possess a unique double membrane system and has, accordingly, lost all of its outer-membrane integral proteins. Lastly, Buchnera from C. cedri revealed an extremely poor repertoire of transporters, with almost no ATP-driven active transport left, despite the clear persistence of the ancestral three-membraned system.

  5. Two odorant-binding proteins mediate the behavioural response of aphids to the alarm pheromone (E-ß-farnesene and structural analogues.

    Directory of Open Access Journals (Sweden)

    Yu Feng Sun

    Full Text Available BACKGROUND: Aphids are agricultural pests of great economical interest. Alternatives to insecticides, using semiochemicals, are of difficult applications. In fact, sex pheromones are of little use as aphids reproduce partenogenetically most of the time. Besides, the alarm pheromone, (E-ß-farnesene for a great number of species, is difficult to synthesize and unstable in the environment. The search for novel semiochemicals to be used in population control can be efficiently approached through the study of the olfactory system at the biochemical level. Recently odorant-binding proteins (OBPs have been shown to play a central role in olfactory recognition, thus becoming the target of choice for designing new semiochemicals. METHODOLOGY/PRINCIPAL FINDINGS: To address the question of how the alarm message is recognised at the level of OBPs, we have tested 29 compounds, including (E-ß-farnesene, in binding assays with 6 recombinant proteins and in behaviour experiments. We have found that good repellents bind OBP3 and/or OBP7, while non repellents present different spectra of binding. These results have been verified with two species of aphids, Acyrthosiphon pisum and Myzus persicae, both using (E-ß-farnesene as the alarm pheromone. CONCLUSIONS: Our results represent further support to the idea (so far convincingly demonstrated only in Drosophila that OBPs are involved in decoding the chemical information of odorants and pheromones, and for the first time provide such evidence in other insect species and using wild-type insects. Moreover, the data offer guidelines and protocols for the discovery of potential alarm pheromones, using ligand-binding assays as a preliminary screening before subjecting selected compounds to behaviour tests.

  6. Dicty_cDB: FC-BI13 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available pisum, Pea Aphid Acyrthosiphon pisum cDNA clone WHAP-002_A12 5', mRNA sequence. 50 3e-04 2 CD036313 |CD036313.1 mgmt...015xA07f.b Mated culture Magnaporthe grisea cDNA clone mgmt015xA07 5', mR

  7. Arabidopsis thaliana—Aphid Interaction

    OpenAIRE

    Louis, Joe; Singh, Vijay,; Shah, Jyoti

    2012-01-01

    Aphids are important pests of plants that use their stylets to tap into the sieve elements to consume phloem sap. Besides the removal of photosynthates, aphid infestation also alters source-sink patterns. Most aphids also vector viral diseases. In this chapter, we will summarize on recent significant findings in plant-aphid interaction, and how studies involving Arabidopsis thaliana and Myzus persicae (Sülzer), more commonly known as the green peach aphid (GPA), are beginning to provide impor...

  8. Crop association to improve biological control: case study on pea and wheat aphids

    OpenAIRE

    Chevalier Mendes Lopes, Thomas; Bodson, Bernard; Francis, Frédéric

    2013-01-01

    Nowadays, strategies used to control aphids in fields of pea, Pisum sativum L., and wheat, Triticum aestivum L., still rely on synthetic insecticides which have negative effects on the environment and human health. This research focused on the development of sustainable alternative methods, with special emphasis on cultural practices and plant management systems. Increasing the diversity within crops may have several beneficial effects on pest control, creating attractive habitats for indigen...

  9. Aphid populations (Hemiptera: Aphidoidea depend of mulching in watermelon production in the Mediterranean region of Croatia

    Directory of Open Access Journals (Sweden)

    K. Zanic

    2013-10-01

    Full Text Available Winged morphs of aphids were investigated under field conditions during 2008, 2010 and 2011 in the Mediterranean region of Croatia. Field experiments were conducted to record aphid diversity and compare polyethylene black mulch to straw mulch and bare soil in terms of their attractiveness to aphid species in a watermelon crop. Aphids were collected weekly using yellow water metal traps from May to July. During the study, 44 species in 31 genera were detected; 36 species in 24 genera were identified in 2008, 18 species in 15 genera were identified in 2010, and 34 species in 25 genera were identified in 2011. The overall seasonal percentage composition showed that Aphis fabae Scopoli and Myzus persicae (Sulzer were consistently eudominant species, whereas Acyrtosiphon pisum (Harris was consistently dominant. Cabbage aphid Brevicoryne brassicae (L. was determined as the dominant species in 2008 and as eudominant species in 2011. Additionally, Macrosiphum rosae (L. was twice recorded as the dominant species, whereas Aphis gossipii Glover was dominant once, and Phorodon humuli (Schrank was eudominant once. Our study also demonstrated that mulching sporadically affected the abundance of individual species. The attractiveness of mulching for aphid species differed between the treatments. It was found that bare soil was attractive to A. pisum and M. rosae, black mulch was attractive to B. helichrysi and P. humuli, and straw mulch was attractive to four aphid species, of which two were eudominant, A. fabae and M. persicae. The presented species are mostly polyphagous, and their preference for certain mulches can be used in crop protection management.

  10. Solenopsis invicta virus 3: mapping of structural proteins, ribosomal frameshifting, and similarities to Acyrthosiphon pisum virus and kelp fly virus

    Science.gov (United States)

    Solenopsis invicta virus 3 (SINV-3) is a positive-sense single-stranded RNA virus that infects the red imported fire ant, Solenopsis invicta. We show that the second open reading frame (ORF) of the dicistronic genome is expressed via a frameshifting mechanism and that the sequences encoding the stru...

  11. Drawing the line

    OpenAIRE

    Saxon, Emma

    2015-01-01

    The pea aphid Acyrthosiphon pisum is an agriculturally important pest of leguminous plants including peas and broad beans. The widespread use of chemical pesticides impacts heavily on the environment, and increases pesticide-resistant pea aphid populations, so alternative strategies are being actively sought. Pseudomonas syringae bacteria are known to infect and kill the pea aphid, and offer a possible control strategy. In this study, the authors measured the effects of injecting P. syringae ...

  12. Dicty_cDB: SFJ609 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 2 CD036313 |CD036313.1 mgmt015xA07f.b Mated culture Magnaporthe grisea cDNA clone mgmt015xA07 5', mRNA seque...ea Aphid Acyrthosiphon pisum cDNA clone WHAP-002_A12 5', mRNA sequence. 50 3e-04

  13. Effects of some Insecticides Applied in Sublethal Concentrations on the Survival and Longevity of Aphidius ervi (Haliday) (Hymenoptera: Aphidiidae) Adults Efecto de algunos Insecticidas Aplicados en Concentraciones Subletales en la Supervivencia y Longevidad de Adultos de Aphidius ervi (Haliday) (Hymenoptera: Aphidiidae)

    OpenAIRE

    Jaime E. Araya; Manuel Araya; María Angélica Guerrero

    2010-01-01

    The effects of four insecticides (dimethoate, pirimicarb, imidacloprid, and spinosad) applied in an ST4 Potter tower at sublethal concentrations (50% of those recommended commercially for aphid control) were studied in the laboratory on aphidiid Aphidius ervi (Haliday) adults, an important parasitoid of the pea aphid Acyrthosiphon pisum (Harris). The most selective treatment on the hymenopteran was imidacloprid, followed in decreasing order by spinosad, pirimicarb, and finally dimethoate, whi...

  14. Ant larval demand reduces aphid colony growth rates in an ant-aphid interaction

    OpenAIRE

    Cook, James M.; Leather, Simon R; Oliver, Tom H.

    2012-01-01

    Ants often form mutualistic interactions with aphids, soliciting honeydew in return for protective services. Under certain circumstances, however, ants will prey upon aphids. In addition, in the presence of ants aphids may increase the quantity or quality of honeydew produced, which is costly. Through these mechanisms, ant attendance can reduce aphid colony growth rates. However, it is unknown whether demand from within the ant colony can affect the ant-aphid interaction. In a factorial exper...

  15. New Records of Aphid Fauna in Turkey

    OpenAIRE

    Kaygin, Azize Toper; Gorur, Gazi; Cota, Figen

    2010-01-01

    Three aphid species were identified as new records for Turkey aphid fauna from Bartin province. These species are Ceruraphis viburnicola (Gillette) (Hemiptera: Aphididae), Dysaphis apiifolia (Theobald) (Hemiptera: Aphididae) and Macrosiphum mordvilkoi Miyazaki (Hemiptera: Aphididae). These records increase the recorded aphid-fauna of Turkey to 433 species.

  16. Contributions to the aphid fauna (Hemiptera, Aphidoidea) of Chukotka Autonomous Okrug with descriptions of five new species.

    Science.gov (United States)

    Stekolshchikov, Andrey V; Khruleva, Olga A

    2015-01-01

    The first study of the aphid fauna from Chukotka Autonomous Okrug has been made; 18 species are reported from this territory, the most north-eastern of Russia and of the Palaeartic Region. Five new species are described: Aphis aquilonalis sp. nov. on Rumex arcticus Trautv.; Aphis beringiensis sp. nov. were collected by yellow trap; Macrosiphoniella (Asterobium) jaroslavi sp. nov. on Artemisia arctica Less. and Artemisia tilesii Ledeb.; Macrosiphum chukotense sp. nov., a polyphagous species found on plants in nine different families; and Pleotrichophorus tuberculatus sp. nov. on Artemisia tilesii Ledeb. In addition, the male and oviparous female of Acyrthosiphon boreale Hille Ris Lambers, 1952 and the fundatrix and male of Pleotrichophorus knowltoni Corpuz-Raros and Cook, 1974 are described for the first time. PMID:26624700

  17. Efficacy of Chemical Mimicry by Aphid Predators Depends on Aphid-Learning by Ants.

    Science.gov (United States)

    Hayashi, Masayuki; Nomura, Masashi; Nakamuta, Kiyoshi

    2016-03-01

    Chemical mimicry is an effective strategy when signal receivers recognize and discriminate models by relying on chemical cues. Some aphid enemies mimic the cuticular chemicals of aphids through various means thus avoiding detection and attack by aphid-tending ants. However, because ants have been reported to learn the chemical signatures of aphids in order to distinguish the aphids, the efficacy of chemical mimicry is predicted to depend on the experience of the ants that had tended aphids. The present study tested this hypothesis using two predator species: larvae of the green lacewing Mallada desjardinsi, and larvae of the ladybeetle Scymnus posticalis. Lacewing larvae carry the carcasses of aphids on which they have preyed upon their backs, and these function via chemical camouflage to reduce the aggressiveness of aphid-tending ants toward the larvae. Ladybeetle larvae reportedly produce a covering of wax structures, and their chemicals appear to attenuate ant aggression. We examined whether the behavior of the ant Tetramorium tsushimae toward these predators changed depending on their aphid-tending experience. Ants moderated their aggressiveness toward both predators when they had previously tended aphids, indicating that chemical mimicry by both aphid predators is dependent on previous experience of the ants in tending aphids. Chemical mimicry by the predators of ant-tended aphids is therefore considered to exploit learning-dependent aphid recognition systems of ants.

  18. Stylet penetration activities by aphids

    NARCIS (Netherlands)

    Tjallingii, W.F.

    1985-01-01

    The composition of stylet penetration behaviour in aphids and its possible role in food-plant selection is the subject of these studies. Evidence is presented that the labium is devoid of external chemoreceptors (Chapter 1). In addition to other morphological data (Wensler & Filshie, 1969; Wensler,

  19. Evidence for the establishment of aphid-eubacterium endosymbiosis in an ancestor of four aphid families.

    OpenAIRE

    Munson, M. A.; Baumann, P.; Clark, M A; Baumann, L; Moran, N A; Voegtlin, D J; Campbell, B C

    1991-01-01

    Aphids (superfamily Aphidoidea) contain eubacterial endosymbionts localized within specialized cells (mycetocytes). The endosymbionts are essential for the survival of the aphid hosts. Sequence analyses of the 16S rRNAs from endosymbionts of 11 aphid species from seven tribes and four families have indicated that the endosymbionts are monophyletic. Furthermore, phylogenetic relationships within the symbiont clade parallel the relationships of the corresponding aphid hosts. Our findings sugges...

  20. AphidBase: A centralized bioinformatic resource for annotation of the pea aphid genome

    OpenAIRE

    Legeai, Fabrice; Shigenobu, Shuji; Gauthier, Jean-Pierre; Colbourne, John; Rispe, Claude; Collin, Olivier; Richards, Stephen; Wilson, Alex C. C.; Tagu, Denis

    2010-01-01

    AphidBase is a centralized bioinformatic resource that was developed to facilitate community annotation of the pea aphid genome by the International Aphid Genomics Consortium (IAGC). The AphidBase Information System designed to organize and distribute genomic data and annotations for a large international community was constructed using open source software tools from the Generic Model Organism Database (GMOD). The system includes Apollo and GBrowse utilities as well as a wiki, blast search c...

  1. Altruistic defence behaviours in aphids

    Directory of Open Access Journals (Sweden)

    Brodeur Jacques

    2010-01-01

    Full Text Available Abstract Background Altruistic anti-predatory behaviours pose an evolutionary problem because they are costly to the actor and beneficial to the recipients. Altruistic behaviours can evolve through indirect fitness benefits when directed toward kin. The altruistic nature of anti-predatory behaviours is often difficult to establish because the actor can obtain direct fitness benefits, or the behaviour could result from selfish coercion by others, especially in eusocial animals. Non-eusocial parthenogenetically reproducing aphids form colonies of clone-mates, which are ideal to test the altruistic nature of anti-predatory defence behaviours. Many aphids release cornicle secretions when attacked by natural enemies such as parasitoids. These secretions contain an alarm pheromone that alerts neighbours (clone-mates of danger, thereby providing indirect fitness benefits to the actor. However, contact with cornicle secretions also hampers an attacker and could provide direct fitness to the actor. Results We tested the hypothesis that cornicle secretions are altruistic by assessing direct and indirect fitness consequences of smearing cornicle secretions onto an attacker, and by manipulating the number of clone-mates that could benefit from the behaviour. We observed parasitoids, Aphidius rhopalosiphi, foraging singly in patches of the cereal aphid Sitobion avenae of varied patch size (2, 6, and 12 aphids. Aphids that smeared parasitoids did not benefit from a reduced probability of parasitism, or increase the parasitoids' handling time. Smeared parasitoids, however, spent proportionately more time grooming and less time foraging, which resulted in a decreased host-encounter and oviposition rate within the host patch. In addition, individual smearing rate increased with the number of clone-mates in the colony. Conclusions Cornicle secretions of aphids were altruistic against parasitoids, as they provided no direct fitness benefits to secretion

  2. Aphid alarm pheromone as a cue for ants to locate aphid partners.

    Directory of Open Access Journals (Sweden)

    François J Verheggen

    Full Text Available The mutualistic relationships that occur between myrmecophilous aphids and ants are based on the rich food supply that honeydew represents for ants and on the protection they provide against aphid natural enemies. While aphid predators and parasitoids actively forage for oviposition sites by using aphid semiochemicals, scouts of aphid-tending ant species would also benefit from locating honeydew resources by orienting toward aphid pheromone sources. The present study aims to provide additional information on the use of Aphis fabae alarm pheromone, i.e. (E-β-farnesene (EβF, by ant scouts. The perception and behavioral impact of EβF on Lasius niger were investigated using electroantennography and two bio-assays measuring their attraction and orientation towards aphid semiochemicals. Pronounced electrical depolarizations were observed from L. niger scout antennae to stimulations of A. fabae alarm pheromone, while other sesquiterpenes elicited weak or no responses. L. niger scouts were significantly attracted toward EβF in a four-arm olfactometer, as well as in an two-choice bioassay. These laboratory results suggest for the first time that low amounts of aphid alarm pheromone can be used by L. niger scouts as a cue indicating the presence of aphid colonies and could therefore mediate the aphid-ant partnership in the field.

  3. Transparency Master: The Annual Aphid Cycle.

    Science.gov (United States)

    Sessions, Mary Lynne

    1983-01-01

    Aphids, often referred to as plant lice, can be found in great numbers on stems, leaves, and flowers of many plants. In many cases these organisms are potentially harmful to their plant hosts. Provided is a description of the annual life cycle of the aphid and an accompanying transparency master. (Author/JN)

  4. Biosynthesis of the phytoalexin pisatin. [Pisum sativum

    Energy Technology Data Exchange (ETDEWEB)

    Preisig, C.L.; Bell, J.N.; Matthews, D.E.; VanEtten, H.D. (Cornell Univ., Ithaca, NY (USA)); Sun, Yuejin; Hrazdina, G. (Cornell Univ., Geneva, NY (USA))

    1990-11-01

    NADPH-dependent reduction of 2{prime},7-dihydroxy-4{prime},5{prime}-methylenedioxyisoflavone to the isoflavanone sophorol, a proposed intermediate step in pisatin biosynthesis, was detected in extracts of Pisum sativum. This isoflavone reductase activity was inducible by treatment of pea seedlings with CuCl{sub 2}. The timing of induction coincided with that of the 6a-hydroxymaackiain 3-O-methyltransferase, which catalyzes the terminal biosynthetic step. Neither enzyme was light inducible. Further NADPH-dependent metabolism of sophorol by extracts of CuCl{sub 2}-treated seedlings was also observed; three products were radiolabeled when ({sup 3}H)sophorol was the substrate, one of which is tentatively identified as maackiain.

  5. Rag1 aphid resistant soybeans alter the movement and distribution of soybean aphid (Hemiptera: Aphididae).

    Science.gov (United States)

    Whalen, Rebecca; Harmon, Jason P

    2012-12-01

    Herbivorous insects often move and distribute according to the quality of the plant they are on, and this behavior could influence interactions with plants bred for herbivore resistance. However, when an insect is normally considered sedentary, less is known about the potential importance of movement. We performed experiments to determine if a resistant soybean variety alters the movement and distribution, both within and between plants, of the soybean aphid Aphis glycines Matsumura. We did this by counting apterous aphids on leaves of resistant and susceptible soybean plants across several days. In individual plant tests aphid distribution was different between susceptible and resistant soybeans. Most notably aphids on resistant plants were quickly found off the original leaf on which they were placed and were ultimately distributed throughout the resistant soybean. Aphids on susceptible plants, however, tended to stay on their initial leaf of placement. Follow up experiments indicated this was primarily because of the movement of individuals and not differential demography on various plant parts. In experiments where aphids were able to walk to an adjacent plant there appeared to be a net movement of aphids off resistant plants and on to susceptible plants. Aphid populations on susceptible plants were higher when the plant was adjacent to a resistant plant than when adjacent to another susceptible plant. The effect of resistant plants on aphid movement and distribution could lead to unintended side-effects such as greater spread of plant viruses or altered effectiveness of biological control agents.

  6. Decomposition analysis of LTREs may facilitate the design of short-term ecotoxicological tests

    OpenAIRE

    Hamda, Natnael T.; Jevtić, Dragan M.; Laskowski, Ryszard

    2012-01-01

    This study compared two methods, based on re-analyzed data from a partly published life table response experiment (LTRE), to help determine the optimal approach for designing ecotoxicological assessments. The 36-day LTRE data recorded the toxic effects of cadmium (Cd) and imidacloprid, alone and in combination, on the reproduction and survivorship of aphids (Acyrthosiphon pisum Harris). We used this data to construct an age-classified matrix model (six age classes, each 6 days long) to estima...

  7. Categorizing sugarcane cultivar resistance to the sugarcane aphid and yellow sugarcane aphid (Hemiptera: Aphididae).

    Science.gov (United States)

    Akbar, W; Showler, A T; Reagan, T E; White, W H

    2010-08-01

    Sugarcane (Saccharum spp.) in Louisiana is colonized by two aphid species, the sugarcane aphid, Melanaphis sacchari (Zehntner), and the yellow sugarcane aphid, Sipha flava (Forbes) (Hemiptera: Aphididae). The main problem associated with M. sacchari is transmission of sugarcane yellow leaf virus, a casual agent of yellow leaf disease whose absence has been added to certification standards for micropropagated sugarcane in Louisiana. Greenhouse studies were conducted to categorize dominant commercial sugarcane cultivars for their ability to tolerate aphid injury and to express antixenotic or antibiotic effects on both aphid species. Antixenosis tests showed no preference among cultivars by either aphid species. Loss of chlorophyll content in tolerance tests also did not show differences among cultivars for both aphid species. However, antibiosis tests revealed that life history parameters such as the duration of the reproductive period and fecundity of both aphid species were negatively affected on 'HoCP 91-555' compared with 'L 97-128'. Estimation of demographic statistics indicated that both aphid species exhibited a significantly lower intrinsic rate of increase (1.8-2.8-fold) and longer doubling time (1.7-3.1-fold) on HoCP 91-555 relative to L 97-128. From these tests, cultivars in the current study can be ranked from most to the least susceptible as L 97-128 > 'LCP 85-384' > 'HoCP 96-540' > 'Ho 95-988' > HoCP 91-555 for M. sacchari and L 97-128 > LCP 85-384 > HoCP 91-555 for S. flava. Therefore, antibiosis is an important category of resistance in sugarcane to both aphid species, and HoCP 91-555 might provide useful germplasm for developing aphid resistant cultivars. PMID:20857758

  8. Seasonal Abundance of Aphids and Aphidophagous Insects in Pecan

    OpenAIRE

    Ghulam Abbas; Dutcher, James D.; Haider Karar

    2012-01-01

    Seasonal occurrence of aphids and aphidophagous insects was monitored for six years (2006–2011) from full leaf expansion in May to leaf fall in October in “Desirable” variety pecan trees that were not treated with insecticides. Aphid outbreaks occurred two times per season, once in the spring and again in the late summer. Yellow pecan and blackmargined aphids exceeded the recommended treatment thresholds one time and black pecan aphids exceeded the recommended treatment levels three times ove...

  9. Community-wide impact of an exotic aphid on introduced tall goldenrod

    OpenAIRE

    Ando, Yoshino; Utsumi, Shunsuke; Ohgushi, Takayuki

    2011-01-01

    1. The aphid Uroleucon nigrotuberculatum Olive, which is specialised to the tall goldenrod, Solidago altissima L., in its native range, has become a dominant species on the introduced tall goldenrod in Japan. How this exotic aphid influenced arthropod communities on the introduced tall goldenrod in aphid-present (spring) and aphid-absent (autumn) seasons was examined, using an aphid removal experiment. 2. In spring, aphid presence increased ant abundance because aphid honeydew attracted fo...

  10. Loss of aphid transmissibility of plum pox virus isolates

    NARCIS (Netherlands)

    Kamenova, I.; Lohuis, H.; Peters, D.

    2002-01-01

    The aphid transmissibility of seven Plum pox virus (PPV) isolates and the amino acid sequences of their coat proteins were analysed Two aphid transmissible isolates PPV-A and PPV-P contained the DAG amino triplet, while DAL or NAG replaced this triplet in the coat proteins of non-aphid transmissible

  11. Root-Lesion Nematodes Suppress Cabbage Aphid Population Development by Reducing Aphid Daily Reproduction.

    Science.gov (United States)

    Hol, W H G; Raaijmakers, Ciska E; Mons, Ilse; Meyer, Katrin M; van Dam, Nicole M

    2016-01-01

    Empirical studies have shown that belowground feeding herbivores can affect the performance of aboveground herbivores in different ways. Often the critical life-history parameters underlying the observed performance effects remain unexplored. In order to better understand the cause for the observed effects on aboveground herbivores, these ecological mechanisms must be better understood. In this study we combined empirical experiments with a modeling approach to analyze the effect of two root feeding endoparasitic nematodes with different feeding strategies on the population growth of the aboveground feeding specialist aphid Brevicoryne brassicae on Brassica nigra. The aim was to test whether emerging differences in life history characteristics (days until reproduction, daily reproduction) would be sufficient to explain observed differences in aphid population development on plants with and without two species of nematodes. Aphid numbers were lower on plants with Pratylenchus penetrans in comparison to aphid numbers on plants with Meloidogyne spp. A dedicated experiment showed that aphid daily reproduction was lower on plants with P. penetrans (3.08 offspring female(-1) day(-1)) in comparison to both uninfested plants and plants with Meloidogyne spp. (3.50 offspring female(-1) day(-1)). The species-specific reduction of aphid reproduction appeared independent of changes in amino acids, soluble sugars or the glucosinolate sinigrin in the phloem. An individual-based model revealed that relatively small differences in reproduction rate per female were sufficient to yield a similar difference in aphid populations as was found in the empirical experiments.

  12. Aphid-AutoEPG software for analysing electrically monitored feeding behaviour of aphids

    Directory of Open Access Journals (Sweden)

    Toni Prüfer

    2014-06-01

    Full Text Available Aphid-AutoEPG is a new software program, developed to acquire and automatically analyse electrical penetration graph (EPG signals used for monitoring plant penetration by aphids. Characteristically EPG signals include waveforms that allow one to study the effects of plants on the acquisition and transmission of viruses, plant protection substances on pests and identify the location of resistance in plants to aphids. The success of electrical monitoring arises from the fact that different species of aphids generate similar EPG patterns. But the visual analysis of EPG waveforms in recorded signals is very time consuming, which has greatly hampered the wider application of EPG technology. To overcome this Aphid-AutoEPG software was developed, which has been extensively tested using data files for several different species of aphids, M. persicae, A. frangulae gossypii, M. albifrons, S. avenae, B. brassicae and N. ribis-nigri. The results have also been compared with visual analyses using Stylet+ software. When used in combination with the user friendly correction options Aphid-AutoEPG is not only easy to use but can also result in a considerable saving in terms of time.

  13. Partial aphid resistance in lettuce negatively affects parasitoids.

    Science.gov (United States)

    Lanteigne, Marie-Eve; Brodeur, Jacques; Jenni, Sylvie; Boivin, Guy

    2014-10-01

    This study investigated the effects of partial plant resistance on the lettuce aphid Nasonovia ribisnigri (Mosley) (Hemiptera: Aphididae), a major pest of cultivated lettuce (Lactuca sativa L.), and one of its parasitoids, Aphidius ervi Haliday (Hymenoptera: Braconidae). Aphids were reared on susceptible (L. sativa variety Estival; S) or partially resistant (Lactuca serriola L. PI 491093; PR) lettuce, and next parasitized by A. ervi females. Fitness proxies were measured for both aphids and parasitoids. Developmental time to adult stage took longer for alate and apterous aphids (an average of 3.5 and 1.5 additional days, respectively) on PR than on S lettuce, and fecundity of alate aphids reared on PR lettuce was reduced by 37.8% relative to those reared on S lettuce. Size (tibia length) and weight of aphids reared on PR lettuce were lower than for aphids reared on S lettuce from the third and second instar onward, respectively. Parasitism of aphids reared on PR plants resulted in lower parasitoid offspring emergence (-49.9%), lower adult female (-30.3%) and male (-27.5%) weight, smaller adult female (-17.5%) and male (-11.9%) size, and lower female fecundity (37.8% fewer eggs) than when parasitoids developed from aphids reared on S plants. Our results demonstrate that partial aphid resistance in lettuce negatively affects both the second and third trophic levels. Host plant resistance in cultivated lettuce may therefore create an ecological sink for aphid parasitoids. PMID:25197882

  14. Drawing the line.

    Science.gov (United States)

    Saxon, Emma

    2015-01-01

    The pea aphid Acyrthosiphon pisum is an agriculturally important pest of leguminous plants including peas and broad beans. The widespread use of chemical pesticides impacts heavily on the environment, and increases pesticide-resistant pea aphid populations, so alternative strategies are being actively sought. Pseudomonas syringae bacteria are known to infect and kill the pea aphid, and offer a possible control strategy. In this study, the authors measured the effects of injecting P. syringae on the survival of pea aphid populations at 24 and 48 hours. The pea aphid population was killed more rapidly (98 % after 24 hours) with a higher concentration of injected bacteria than in the control or with lower concentrations, indicating that a P. syringae-based control strategy may be a useful alternative to conventional pesticides. PMID:26438421

  15. Pan trapping soybean aphids (Hemiptera: Aphididae) using attractants.

    Science.gov (United States)

    Behrens, Nicholas S; Zhu, Junwei; Coats, Joel R

    2012-06-01

    Since its introduction into the United States in the past 10 yr, soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), has been a damaging pest to soybean, Glycine max (L.) Merrill. During 2008 and 2009, fields in central and north central Iowa experienced pockets of high soybean aphid populations. Electroantennograms have shown that soybean aphid alatae are capable of detecting host plant volatiles and sex pheromones. Here, we evaluated baited pan traps as a potential soybean aphid attractant. Yellow pan traps were placed in soybean fields after planting along with lures that contained plant volatiles and sex pheromones in 2008 or sex pheromones only in 2009. Pan trap contents were collected weekly, and plant counts also were conducted. Aphids were identified, and soybean aphids were counted to determine whether one chemical lure was more attractive to spring migrants than other lures. In both years, soybean aphids collected in pan traps with lures were not significantly different from the other products tested. PMID:22812127

  16. Early interactions during the encounter of plants, aphids and arboviruses.

    Science.gov (United States)

    Bak, Aurélie; Martinière, Alexandre; Blanc, Stéphane; Drucker, Martin

    2013-06-01

    Aphids infest many plants and cause damage by depriving them of nutrients and by transmitting many viral diseases. Aphid infestation and arbovirus transmission are controlled by establishment (or not) of a compatible reaction between the insects and the plants. This reaction is the result of defense reactions of the plant and counter-defense reactions of the parasite. Contrarily to plant-bacteria, plant-fungi and plant-herbivorous insects pathosystems, the plant-aphid pathosystem is understudied, although recent advances have begun to uncover some of its details. Especially the very early steps in plant-aphid interactions are hardly known. We here resume the present knowledge of these interactions. We discuss further how an aphid-transmitted plant virus that is transmitted during the first moments of the plant-aphid encounter, might help to study the very early plant aphid interactions.

  17. Symbiotic bacterium modifies aphid body color.

    Science.gov (United States)

    Tsuchida, Tsutomu; Koga, Ryuichi; Horikawa, Mitsuyo; Tsunoda, Tetsuto; Maoka, Takashi; Matsumoto, Shogo; Simon, Jean-Christophe; Fukatsu, Takema

    2010-11-19

    Color variation within populations of the pea aphid influences relative susceptibility to predators and parasites. We have discovered that infection with a facultative endosymbiont of the genus Rickettsiella changes the insects' body color from red to green in natural populations. Approximately 8% of pea aphids collected in Western Europe carried the Rickettsiella infection. The infection increased amounts of blue-green polycyclic quinones, whereas it had less of an effect on yellow-red carotenoid pigments. The effect of the endosymbiont on body color is expected to influence prey-predator interactions, as well as interactions with other endosymbionts. PMID:21097935

  18. Pea (Pisum sp.) genetic resources, its analysis and exploration

    Science.gov (United States)

    Pea is important temperate region pulse, with feed, fodder and vegetable uses. Originated and domesticated in Middle East and Mediterranean, it formed important dietary components of early civilizations. Although Pisum is a small genus with two or three species, it is very diverse and structured, r...

  19. National Plant Diagnostic Network, Taxonomic training videos: Introduction to Aphids - Part 1

    Science.gov (United States)

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides visual instruction on important subject areas for aphid examination and identification. Aphid topics such as classification, morphology, plant disease transmission, and references are discussed. This dis...

  20. Infestation and natural parasitism of aphids in single and mixed pastures of black oats and ryegrass

    OpenAIRE

    Vinícius Soares Sturza; Sônia Poncio; Aline Bosak dos Santos; Marcelo Lopes-da-Silva

    2012-01-01

    Some species of aphids are major pests on cereal crops and grass pastures. Usually these pests are not adequately controlled in pasture lands that become sources of aphid infestations to cereal crops. The dynamics of aphids and the incidence of natural enemies are less known in pasture systems than in cereal fields. The objective of this work was to assess the aphid infestation and natural aphid parasitism in different pasture composition. Three hypotheses were tested: 1- the aphid species co...

  1. Molecular sabotage of plant defense by aphid saliva

    OpenAIRE

    Will, T; Tjallingii, W.F.; Thönnessen, A.; Bel,, T.

    2007-01-01

    Aphids, which constitute one of the most important groups of agricultural pests, ingest nutrients from sieve tubes, the photoassimilate transport conduits in plants. Aphids are able to successfully puncture sieve tubes with their piercing mouthparts (stylets) and ingest phloem sap without eliciting the sieve tubes' normal occlusion response to injury. Occlusion mechanisms are calcium-triggered and may be prevented by chemical constituents in aphid saliva injected into sieve tubes before and d...

  2. Life-history strategies affect aphid preference for yellowing leaves

    OpenAIRE

    Holopainen, Jarmo K.; Semiz, Gürkan; Blande, James D

    2009-01-01

    According to the nutrient-translocation hypothesis, yellowing tree leaves are colonized by aphids at the end of the growing season owing to improved availability of nutrients in the phloem sap after chlorophyll degradation. We measured aphid densities on potted Betula pendula seedlings in a field site where a small proportion of foliage rapidly turned yellow before normal autumn coloration as a consequence of root anoxia. The number of adults and nymphs of the birch-feeding specialist aphids ...

  3. Crop association to improve aphid biological control

    OpenAIRE

    Chevalier Mendes Lopes, Thomas; Bosquée, Emilie; Bodson, Bernard; Francis, Frédéric

    2014-01-01

    This research focused on the development of sustainable alternative methods to control aphids, giving special emphasis on cultural practices and plant management systems. Increasing the diversity within crops may have several beneficial effects on pest control, creating attractive habitats for indigenous beneficial fauna and simultaneously deterring pests (“push-pull” approach). In this field study, two wheat/pea associations (mixed cropping and strip cropping) where compared to monocultures ...

  4. Antagonistic effects of soybean viruses on soybean aphid performance.

    Science.gov (United States)

    Donaldson, Jack R; Gratton, Claudio

    2007-08-01

    Although there is long-standing recognition that pest complexes require different management approaches than individual pests, relatively little research has explored how pests interact. In particular, little is known of how herbivorous insects and plant pathogens interact when sharing the same host plant. The soybean aphid, Aphis glycines Mastumura, a recently introduced pest of soybean in the upper midwestern United States, and a complex of plant viruses vectored to soybean by insects have become a major concern for growers in the region. Given the abundance of soybean aphid and the increase in virus incidence in recent years, soybean aphids often use soybean infected by plant viral pathogens. We tested the hypothesis that soybean aphid performance is affected by virus infection of soybean plants. We conducted a series of field and laboratory experiments that examined how infection of soybeans with the common plant viruses, alfalfa mosaic, soybean mosaic, and bean pod mottle viruses, influenced soybean aphid performance. Soybean plants (in the field and laboratory) were hand inoculated with individual viruses, and aphids were allowed to colonize plants naturally in field experiments or added to the plants in clip-cages or within mesh bags in laboratory assays. In the field, aphid density on uninfected control soybean plants was nearly double that on infected plants. In laboratory assays, aphid population growth rates were on average 20% lower for aphids on virus infected compared with uninfected plants. Life table analyses showed that increased mortality on virus-infected plants likely explain differences in aphid population growth. Although there was some heterogeneity in the significance of treatment effects among different experiments, when independent experiments are taken together, there is on average an overall negative effect of these viruses on soybean aphids. PMID:17716484

  5. National Plant Diagnostic Network, Taxonomic training videos: Introduction to Aphids - Part 2

    Science.gov (United States)

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides visual instruction on important subject areas for aphid regulatory issues. Here the subject of aphids as they relate to disease transmission, biology, identification, and pathways is addressed. Aphid topi...

  6. Molecular sabotage of plant defense by aphid saliva

    NARCIS (Netherlands)

    Will, T.; Tjallingii, W.F.; Thönnessen, A.; Bel, van A.J.E.

    2007-01-01

    Aphids, which constitute one of the most important groups of agricultural pests, ingest nutrients from sieve tubes, the photoassimilate transport conduits in plants. Aphids are able to successfully puncture sieve tubes with their piercing mouthparts (stylets) and ingest phloem sap without eliciting

  7. Seasonal Abundance of Aphids and Aphidophagous Insects in Pecan

    Directory of Open Access Journals (Sweden)

    Ghulam Abbas

    2012-12-01

    Full Text Available Seasonal occurrence of aphids and aphidophagous insects was monitored for six years (2006–2011 from full leaf expansion in May to leaf fall in October in “Desirable” variety pecan trees that were not treated with insecticides. Aphid outbreaks occurred two times per season, once in the spring and again in the late summer. Yellow pecan and blackmargined aphids exceeded the recommended treatment thresholds one time and black pecan aphids exceeded the recommended treatment levels three times over the six seasons. Increases in aphidophagous insect abundance coincided with aphid outbreaks in five of the six seasons. Among aphidophagous insects Harmonia axyridis and Olla v-nigrum were frequently collected in both the tree canopy and at the ground level, whereas, Coccinella septempunctata, Hippodamia convergens were rarely found in the tree canopy and commonly found at the ground level. Green lacewing abundance was higher in the ground level than in the tree canopy. Brown lacewings were more abundant in the tree canopy than at the ground level. Dolichopodid and syrphid fly abundance, at the ground level increased during peak aphid abundance in the tree canopy. Application of an aqueous solution of fermenting molasses to the pecan foliage during an aphid outbreak significantly increased the abundance of ladybeetles and lacewings and significantly reduced the abundance of yellow pecan, blackmargined and black pecan aphids.

  8. Seasonal Abundance of Aphids and Aphidophagous Insects in Pecan.

    Science.gov (United States)

    Dutcher, James D; Karar, Haider; Abbas, Ghulam

    2012-01-01

    Seasonal occurrence of aphids and aphidophagous insects was monitored for six years (2006-2011) from full leaf expansion in May to leaf fall in October in "Desirable" variety pecan trees that were not treated with insecticides. Aphid outbreaks occurred two times per season, once in the spring and again in the late summer. Yellow pecan and blackmargined aphids exceeded the recommended treatment thresholds one time and black pecan aphids exceeded the recommended treatment levels three times over the six seasons. Increases in aphidophagous insect abundance coincided with aphid outbreaks in five of the six seasons. Among aphidophagous insects Harmonia axyridis and Olla v-nigrum were frequently collected in both the tree canopy and at the ground level, whereas, Coccinella septempunctata, Hippodamia convergens were rarely found in the tree canopy and commonly found at the ground level. Green lacewing abundance was higher in the ground level than in the tree canopy. Brown lacewings were more abundant in the tree canopy than at the ground level. Dolichopodid and syrphid fly abundance, at the ground level increased during peak aphid abundance in the tree canopy. Application of an aqueous solution of fermenting molasses to the pecan foliage during an aphid outbreak significantly increased the abundance of ladybeetles and lacewings and significantly reduced the abundance of yellow pecan, blackmargined and black pecan aphids. PMID:26466738

  9. Genome-wide association mapping of soybean aphid resistance traits

    Science.gov (United States)

    Soybean aphid is the most damaging insect pest of soybean in the Upper Midwest and is primarily controlled by insecticides. Soybean aphid resistance (i.e., Rag genes) has been documented in some soybean lines at chromosomes 6, 7, 13, and 16, but more sources of resistance are needed. Genome-wide ass...

  10. Breeding for resistance to the sugarcane aphid [Melanaphis sacchari (Zehntner)

    Science.gov (United States)

    The sugarcane aphid [Melanaphis sacchari] (SCA) was first reported to damage sorghum [Sorghum bicolor (L.) Moench] in the United States in Louisiana and Texas in 2013, and was subsequently detected in Oklahoma and the Mississippi Delta. In 2014, the aphid spread and was eventually reported in state...

  11. Anomalous stylet punctures of phloem sieve elements by aphids

    NARCIS (Netherlands)

    Tjallingii, W.F.; Gabrys, B.

    1999-01-01

    A deviating type of potential drop (pd), i.e. the electrically recorded intracellular punctures during the pathway phase of plant penetration by aphids, is described and discussed. This so-called repetitive pd (R-pd) has been observed in 4 aphid species, two on herbs and two on sycamore. Apart from

  12. New aphid (Aphidoidea) records for the Netherlands (1984-2005)

    NARCIS (Netherlands)

    Piron, P.G.M.

    2009-01-01

    Presented are 18 species.of aphids in combination with their food-plants found in The Netherlands from 1984 to 2005 not earlier described here. Among these are well-known species that are caught with the high suction trap andlor MOERICKE yellow water traps and aphids new for The Netherlands. The tax

  13. Predator efficiency reconsidered for a ladybird-aphid system

    Directory of Open Access Journals (Sweden)

    Pavel eKindlmann

    2015-03-01

    Full Text Available Some experiments indicate that ladybirds can significantly suppress aphid abundance. For example, exclusion of predators by caging aphid-infested plants repeatedly results in higher aphid populations and faster aphid population growth rates. However, aphidophagous ladybirds have never proved effective in controlling aphid populations in the field, which is consistent with the theoretical prediction that long-lived predators cannot be effective in controlling a short-lived prey (the generation time ratio hypothesis, GTR. To resolve this paradox, field experiments, involving two species of ladybirds, Coccinella septempunctata bruckii and Harmonia axyridis were used to determine their efficiency in suppressing populations of the aphid, Aphis gossypii, on small shrubs of Hibiscus syriacus under natural conditions. Instead of by caging, the effect of each ladybird species on aphid population dynamics was determined by removing all the eggs of C. septempunctata from 8 shrubs, those of H. axyridis from a further 8 shrubs, all those of both species from an additional 12 shrubs and leaving the eggs on 6 control shrubs. These predators did not have a negative effect on the peak numbers of the aphids. Thus one should be cautious when interpreting the results of cage experiments, used to assess the efficiency of predators in reducing the abundance of their prey.

  14. Detection of novel QTLs for foxglove aphid resistance in soybean

    Science.gov (United States)

    Foxglove aphid, Aulacorthum solani (Kaltenbach), is a Hemipteran insect that infected a wide variety of plants worldwide and caused serious yield losses in crops. The objective of this study was to identify the putative QTL for foxglove aphid resistance in wild soybean, PI 366121, (Glycine soja Sieb...

  15. Tracking the global dispersal of a cosmopolitan insect pest, the peach potato aphid

    OpenAIRE

    Kasprowicz Louise; Margaritopoulos John T; Malloch Gaynor L; Fenton Brian

    2009-01-01

    Abstract Background Global commerce and human transportation are responsible for the range expansion of various insect pests such as the plant sucking aphids. High resolution DNA markers provide the opportunity to examine the genetic structure of aphid populations, identify aphid genotypes and infer their evolutionary history and routes of expansion which is of value in developing management strategies. One of the most widespread aphid species is the peach-potato aphid Myzus persicae, which i...

  16. Inheritance of enlarged leaf mutations in pea (Pisum sativum L.)

    International Nuclear Information System (INIS)

    In the present study, two pea (Pisum sativum L.) mutants experimentally obtained after gamma irradiation of dry seeds are described. Both mutants were characterized by enlarged leaf size. The mutant 2/462 was shown to have semi-dominant inheritance pattern; 2/927 was sterile and inherited monogenic recessive. The induced mutations have pleiotropic effect, affecting morphological and reproductive traits. New mutants had similar phenotypes to previously named mutants latifolium (lat) and cabbage leaf (calf), but no allelism tests were made between the new and the previously reported mutants. Both mutant lines may be useful plant material for research on leaf development

  17. Genetic study of necrotic leaf pea (Pisum sativum L.) mutants

    International Nuclear Information System (INIS)

    Four pea (Pisum sativum L.) mutants characterized by necrotic leaves were isolated following mutagenesis. The mutants were shown to have single-gene recessive inheritance, characterized morphologically and for seed production. New mutants 1/704, 1/711M, XV/915 and 2/352 had similar phenotypes, respectively, to previously named mutants dgl (degenerating leaves), nec (necrosis), bls (brown leaf spots) and bls (brown leaf), but no allelism tests were made between the new and the previously reported mutants. Mutants 1/704 and 1/711M were shown to be non-allelic. The mutation in line 2/352 may be useful as a genetic marker

  18. Preacondicionamiento de la Semilla de Arveja (Pisum sativum L.)

    OpenAIRE

    Henao Omar A; Marciales Bertha N; Medina Clara I; Lobo A. Mario

    1997-01-01

    En el Centro de Investigación "La selva ", de la Corporación Colombiana de Investigación Agropecuaria. CORPOICA, ubicado en Rionegro, Antioquia. a 2120 msnm, con una temperatura promedio de 17 °C y perteneciente a la formación ecológica Bosque Húmedo Montano Bajo, se llevó a cabo un estudio con la especie arveja (Pisum sativum L.), con el fin de evaluar el efecto del tratamiento de preacondicionamiento de las semillas, conocido como humedecimiento-secado, sobre la germinación, la emergencia y...

  19. Preacondicionamiento de la semilla de arveja (pisum sativum l.)

    OpenAIRE

    Henao, Omar A; Marciales, Bertha N; Medina, Clara I; Lobo A., Mario

    2012-01-01

    En el Centro de Investigación "La selva ", de la Corporación Colombiana de Investigación Agropecuaria. CORPOICA, ubicado en Rionegro, Antioquia. a 2120 msnm, con una temperatura promedio de 17 °C y perteneciente a la formación ecológica Bosque Húmedo Montano Bajo, se llevó a cabo un estudio con la especie arveja (Pisum sativum L.), con el fin de evaluar el efecto del tratamiento de preacondicionamiento de las semillas, conocido como humedecimiento-secado, sobre la germinación, la emergencia y...

  20. Aphid Transmission of the Ontario Isolate of Plum Pox Virus.

    Science.gov (United States)

    Lowery, D Thomas; Vickers, Patricia M; Bittner, Lori A; Stobbs, Lorne W; Foottit, Robert G

    2015-10-01

    Utilization of timed virus acquisition access probes in studies of plum pox virus (PPV) transmission by aphids demonstrated that endemic species transmitted the virus readily from plum, Prunus domestica (L.) Batsch; peach, P. persica (L.); or dwarf flowering almond, P. glandulosa Thunberg., to peach seedlings. The green peach aphid, Myzus persicae (Sulzer), was shown to be the most efficient vector. Acquisition of virus by green peach aphids from infected peach leaves resulted in 18-28% infected peach seedlings, while aphids previously fed on infected leaves of plum transferred virus to 36% of peach seedlings. Although the spirea aphid, Aphis spiraecola (Patch), was a less efficient vector than M. persicae it is perhaps more important for the spread of PPV due to its greater abundance and occurrence earlier in the season when peach trees are thought to be more susceptible to infection. Virus transmission rates varied depending on the virus source and healthy test plant species. In contrast to many previous studies, aphid inoculation of the experimental host Nicotiana benthamiana Domin occurred at a low rate, never exceeding 4%. Acquisition of PPV by M. persicae from infected peach fruit was greatly reduced compared with acquisition from leaves. The results of this research indicate that the Ontario isolate of PPV-D is readily transmissible by aphids to peach and natural spread of the virus needs to be considered in future management or eradication programs.

  1. Life-history strategies affect aphid preference for yellowing leaves.

    Science.gov (United States)

    Holopainen, Jarmo K; Semiz, Gürkan; Blande, James D

    2009-10-23

    According to the nutrient-translocation hypothesis, yellowing tree leaves are colonized by aphids at the end of the growing season owing to improved availability of nutrients in the phloem sap after chlorophyll degradation. We measured aphid densities on potted Betula pendula seedlings in a field site where a small proportion of foliage rapidly turned yellow before normal autumn coloration as a consequence of root anoxia. The number of adults and nymphs of the birch-feeding specialist aphids Euceraphis betulae, Betulaphis brevipilosa and Callipterinella tuberculata were counted from leaves on each of the 222 plants. Aphids were detected on 19 per cent of green leaves and on 41 per cent of yellow leaves. There was no indication of aphid avoidance of yellow leaves, and the number of winged (alate) viviparous E. betulae adults and their nymphs were significantly higher on yellow leaves than on green leaves, while the numbers of apterous B. brevipilosa and C. tuberculata did not differ between the leaf colour types. Our result suggests that only aphid species with alate generation during colour change can take advantage of yellowing leaves. This may explain the exceptional abundance of E. betulae compared with other aphid species on birches. PMID:19535364

  2. Color polymorphism in an aphid is maintained by attending ants.

    Science.gov (United States)

    Watanabe, Saori; Murakami, Taiga; Yoshimura, Jin; Hasegawa, Eisuke

    2016-09-01

    The study of polymorphisms is particularly informative for enhancing our understanding of phenotypic and genetic diversity. The persistence of polymorphism in a population is generally explained by balancing selection. Color polymorphisms that are often found in many insects and arthropods are prime examples of the maintenance of polymorphisms via balancing selection. In some aphids, color morphs are maintained through frequency-dependent predation by two predatory insects. However, the presence of color polymorphism in ant-attended aphids cannot be explained by traditional balancing selection because these aphids are free from predation. We examined the selective advantages of the existence of two color (red and green) morphs in the ant-attended aphid, Macrosiphoniella yomogicola, in fields. We measured the degree of ant attendance on aphid colonies with different proportions of color morphs. The results show that the ants strongly favor aphid colonies with intermediate proportions of the two color morphs. The relationship between the degree of ant attendance and the proportion of color morphs in the field is convex when aphid colony size and ant colony size are controlled. This function has a peak of approximately 65% of green morphs in a colony. This system represents the first case of a balancing polymorphism that is not maintained by opposing factors but by a symbiotic relationship. PMID:27617289

  3. Multiple cues for winged morph production in an aphid metacommunity.

    Directory of Open Access Journals (Sweden)

    Mohsen Mehrparvar

    Full Text Available Environmental factors can lead individuals down different developmental pathways giving rise to distinct phenotypes (phenotypic plasticity. The production of winged or unwinged morphs in aphids is an example of two alternative developmental pathways. Dispersal is paramount in aphids that often have a metapopulation structure, where local subpopulations frequently go extinct, such as the specialized aphids on tansy (Tanacetum vulgare. We conducted various experiments to further understand the cues involved in the production of winged dispersal morphs by the two dominant species of the tansy aphid metacommunity, Metopeurum fuscoviride and Macrosiphoniella tanacetaria. We found that the ant-tended M. fuscoviride produced winged individuals predominantly at the beginning of the season while the untended M. tanacetaria produced winged individuals throughout the season. Winged mothers of both species produced winged offspring, although in both species winged offspring were mainly produced by unwinged females. Crowding and the presence of predators, effects already known to influence wing production in other aphid species, increased the percentage of winged offspring in M. tanacetaria, but not in M. fuscoviride. We find there are also other factors (i.e. temporal effects inducing the production of winged offspring for natural aphid populations. Our results show that the responses of each aphid species are due to multiple wing induction cues.

  4. Aphids (Hemiptera, Aphididae on ornamental plants in greenhouses in Bulgaria

    Directory of Open Access Journals (Sweden)

    Mariya Yovkova

    2013-07-01

    Full Text Available Investigations on the species composition and host range of aphids on ornamental greenhouse plants in Bulgaria was conducted over a period of five years, from 2008 to 2012. Twenty greenhouses, growing ornamentals for landscaping, plant collections and other purposes were observed. They were located in the regions of Sofia, Plovdiv, Smolyan, Pavlikeni, Varna and Burgas. The total number of collected aphid samples was 279. Their composition included 33 aphid species and one subspecies from 13 genera and 5 subfamilies. Twenty-eight species were found to belong to subfamily Aphidinae. Almost 70 % of all recorded species were polyphagous. The most widespread aphid species was Myzus persicae, detected in 13 greenhouses all year round, followed by Aulacorthum solani (10 greenhouses and Aphis gossypii (9 greenhouses. The widest host range was shown by Myzus persicae (43 hosts, Aulacorthum solani (32 hosts and Aulacorthum circumflexum (23 hosts.The list of host plants includes 114 species from 95 genera and 58 families. The greatest variety of aphid species was detected on Hibiscus (9 species. Out of all aphid samples 12.9 % were collected on Hibiscus and 6.8 %, on Dendranthema. The greatest variety of aphid species was detected on Hibiscus (9 species.Periphyllus californiensis and Aphis (Aphis fabae mordvilkoi are reported for the first time for Bulgaria. Furthermore, Aphis spiraecola has been found in new localities and has widened its host range in this country.

  5. Bacterial communities of two parthenogenetic aphid species cocolonizing two host plants across the Hawaiian Islands.

    Science.gov (United States)

    Jones, Ryan T; Bressan, Alberto; Greenwell, April M; Fierer, Noah

    2011-12-01

    Aphids (Hemiptera: Aphididae) have been the focus of several studies with respect to their interactions with inherited symbionts, but bacterial communities of most aphid species are still poorly characterized. In this research, we used bar-coded pyrosequencing to characterize bacterial communities in aphids. Specifically, we examined the diversity of bacteria in two obligately parthenogenetic aphid species (the melon aphid, Aphis gossypii, and the cardamom aphid, Pentalonia caladii) cocolonizing two plant species (taro, Colocasia esculenta, and ginger, Alpinia purpurata) across four Hawaiian Islands (Hawaii, Kauai, Maui, and Oahu). Results from this study revealed that heritable symbionts dominated the bacterial communities for both aphid species. The bacterial communities differed significantly between the two species, and A. gossypii harbored a more diverse bacterial community than P. caladii. The bacterial communities also differed across aphid populations sampled from the different islands; however, communities did not differ between aphids collected from the two host plants. PMID:21965398

  6. Ants farm subterranean aphids mostly in single clone groups

    DEFF Research Database (Denmark)

    Ivens, Aniek B.F.; Kronauer, Daniel Jan Christoph; Pen, Ido;

    2012-01-01

    if not exclusively asexual reproduction, we here investigate aphid diversity within and between ant nest mounds. Results The three focal species (Geoica utricularia, Forda marginata and Tetraneura ulmi) had considerable clonal diversity at the population level. Yet more than half of the ant mounds contained just...... separated with more than 95% of the aphid chambers containing individuals of a single clone. Conclusions L. flavus “husbandry” is characterized by low aphid “livestock” diversity per colony, especially at the nest-chamber level, but it lacks the exclusive monocultures known from other cultivation mutualisms...... benefitting the domesticated aphids as long as their clone-mates reproduce successfully. The cost-benefit logic of this type of polyculture husbandry has striking analogies with human farming practices based on slaughtering young animals for meat to maximize milk-production by a carefully regulated adult...

  7. Identification of Soybean Resources of Resistance to Aphids

    Institute of Scientific and Technical Information of China (English)

    WU Tian-long; MA Xiao-hong; YAO Lu-ming; WANG Biao

    2009-01-01

    Four soybean [Glycine max (L.) Merr.] cultivars with soybean aphid resistance (Aphis glycines Matsmura), P189, P203, P574,and P746, were identified in field test, choice test, and non-choice test. The grade of resistance to aphids and the damage index of P189, P203, and P746 were significantly different from the susceptible cultivars (P=0.05). P574 and P746 showed antibiosis resistance, preventing aphids from reproducing on the plants. P203 showed antixenosis resistance, preventing aphids from reproducing in field test and choice test, but susceptible in non-choice test. Population development on plants was significantly different in field test, choice test, and non-choice test, which was caused by different selective pressures.

  8. Venomous protease of aphid soldier for colony defense

    OpenAIRE

    Kutsukake, Mayako; Shibao, Harunobu; Nikoh, Naruo; Morioka, Mizue; Tamura, Tomohiro; Hoshino, Tamotsu; Ohgiya, Satoru; Fukatsu, Takema

    2004-01-01

    In social aphids, morphological, behavioral, and physiological differences between soldiers and normal insects are attributed to differences in gene expression between them, because they are clonal offspring parthenogenetically produced by the same mothers. By using cDNA subtraction, we identified a soldier-specific cysteine protease of the family cathepsin B in a social aphid, Tuberaphis styraci, with a second-instar soldier caste. The cathepsin B gene was specifically expressed in soldiers ...

  9. Artificial nighttime light changes aphid-parasitoid population dynamics

    OpenAIRE

    Dirk Sanders; Rachel Kehoe; Katie Tiley; Jonathan Bennie; Dave Cruse; Davies, Thomas W; F J Frank van Veen; Gaston, Kevin J

    2015-01-01

    Artificial light at night (ALAN) is recognized as a widespread and increasingly important anthropogenic environmental pressure on wild species and their interactions. Understanding of how these impacts translate into changes in population dynamics of communities with multiple trophic levels is, however, severely lacking. In an outdoor mesocosm experiment we tested the effect of ALAN on the population dynamics of a plant-aphid-parasitoid community with one plant species, three aphid species an...

  10. Spontaneous electrical activity recorded from the aphid central nervous system

    OpenAIRE

    Nguyen, Dan-Thanh T.; Blacker, Melissa J.; Goodchild, James A.

    2012-01-01

    Whilst many classes of insecticides target the insect central nervous system (CNS), their effects in the CNS of pest aphids have not been demonstrated. In this report, we describe an electrophysiological method for recording spontaneous neuronal activity from the giant willow aphid (Tuberolachnus salignus). Using extracellular recording electrodes and two analysis methods (threshold and template search), spontaneous spike activity was shown to exhibit sensitivity to the neuroexcitatory insect...

  11. New data about the Costa Rican aphid fauna (Hemiptera, Aphididae)

    OpenAIRE

    Zamora Mejías, D.; Pérez Hidalgo, N.; W. Villalobos; Hanson, P

    2012-01-01

    Aphids were collected from 39 locations throughout Costa Rica, representing a wide altitudinal range, and from both crops and native plants. In total, 48 species of aphids were identified, associated with 62 families and 111 species of plants, many of these representing new host plant records. Aphis nasturtii Kaltenbach, 1843 is reported here for the first time in Central America and Trichosiphonaphis (Xenomyzus) polygoni (van der Goot, 1917) for the ...

  12. Biological control of tortricids and aphids in strawberries

    DEFF Research Database (Denmark)

    Sigsgaard, Lene; Enkegaard, Annie; Eilenberg, Jørgen;

    Cropping practice and biological control can contribute to reduced pesticide use in strawberries. Organic strawberries are less attacked by strawberry tortricid and buckwheat flower strips can augment its natural enemies. Against shallot aphid the two-spot ladybird is promising.......Cropping practice and biological control can contribute to reduced pesticide use in strawberries. Organic strawberries are less attacked by strawberry tortricid and buckwheat flower strips can augment its natural enemies. Against shallot aphid the two-spot ladybird is promising....

  13. Stylet penetration behaviors of the cotton aphid Aphis gossypii on transgenic Bt cotton

    Institute of Scientific and Technical Information of China (English)

    Kun Xue; Xiao-Ying Wang; Cui-Hong Huang; Rong-Jiang Wang; Biao Liu; Feng-Ming Yan; Chong-Ren Xu

    2009-01-01

    Stylet penetration behaviors of cotton aphids Aphis gossypii Glover on a tmnsgenic cotton line "GK-12" expressing Bt toxic protein ofCry1A (Bt cotton) and a non-Bt conventional cotton line "Simian-3" (CK cotton) were recorded with the direct current electrical penetration graph (DC-EPG) technique. Cotton aphids reared on Bt cotton (abbreviated as Bt-aphids) and its parental non-Bt control line (CK-aphids) for more than 20 generations each, were used for recordings on two cotton lines. Among 47 selected parameters reflecting the activities of aphid stylets within plant tissues, there were eight parameters of CK-aphids showing significant differences between the performances of CK-aphids on Bt cotton and CK cotton, while for Bt-aphids, all the parameters were statistically equal between the performances on the two cotton lines. All parameters with significant differences indicated that CK-aphids could penetrate into Bt cotton more easily, but the phloem saps of Bt cotton were not as good as those of regular cotton for CK-aphids. Based on the present results, we concluded that there were some factors in Bt cotton affecting penetration behaviors of CK-aphids, but it just took several generations for CK-aphids to completely adapt Bt cotton, and Bt-aphids could feed on two cotton lines without difficulty.

  14. Agronomy of strip intercropping broccoli with alyssum for biological control of aphids

    Science.gov (United States)

    Organic broccoli growers in California typically control aphids by intercropping broccoli with strips of alyssum (Lobularia maritima (L.) Desv.) which attracts hoverflies (Diptera: Syrphidae) that are important predators of aphids. A three year study with transplanted organic broccoli in Salinas, ...

  15. Species response to environmental change: impacts of food web interactions and evolution.

    Science.gov (United States)

    Harmon, Jason P; Moran, Nancy A; Ives, Anthony R

    2009-03-01

    How environmental change affects species abundances depends on both the food web within which species interact and their potential to evolve. Using field experiments, we investigated both ecological and evolutionary responses of pea aphids (Acyrthosiphon pisum), a common agricultural pest, to increased frequency of episodic heat shocks. One predator species ameliorated the decrease in aphid population growth with increasing heat shocks, whereas a second predator did not, with this contrast caused by behavioral differences between predators. We also compared aphid strains with stably inherited differences in heat tolerance caused by bacterial endosymbionts and showed the potential for rapid evolution for heat-shock tolerance. Our results illustrate how ecological and evolutionary complexities should be incorporated into predictions of the consequences of environmental change for species' populations.

  16. New Cyt-like δ-endotoxins from Dickeya dadantii: structure and aphicidal activity

    OpenAIRE

    Loth, Karine; Costechareyre, Denis; Effantin, Géraldine; Rahbé, Yvan; Condemine, Guy; Landon, Céline; DA SILVA, Pedro

    2015-01-01

    International audience; In the track of new biopesticides, four genes namely cytA, cytB, cytC and cytD encoding proteins homologous to Bacillus thuringiensis (Bt) Cyt toxins have been identified in the plant pathogenic bacteria Dickeya dadantii genome. Here we show that three Cyt-like d-endotoxins from D. dadantii (CytA, CytB and CytC) are toxic to the pathogen of the pea aphid Acyrthosiphon pisum in terms of both mortality and growth rate. The phylogenetic analysis of the comprehensive set o...

  17. Cereal aphid colony turnover and persistence in winter wheat.

    Directory of Open Access Journals (Sweden)

    Linton Winder

    Full Text Available An understanding of spatial and temporal processes in agricultural ecosystems provides a basis for rational decision-making with regards to the management and husbandry of crops, supporting the implementation of integrated farming strategies. In this study we investigated the spatial and temporal distribution of aphid pests (Sitobion avenae and Metopolophium dirhodum within winter wheat fields. Using an intensive sampling programme we investigated distributions at both the small (single shoot and large (field scales. Within two fields, a grid with 82 locations was established (area 120 m by 168 m. At each location, 25 shoots were individually marked and aphid counts by observation conducted on 21 and 22 occasions as the crop matured, resulting in 43,050 and 45,100 counts being conducted in the two fields respectively. We quantified field scale spatial distributions, demonstrating that spatial pattern generally emerged, with temporal stability being both species- and field- dependent. We then measured turnover of colonies at the small (individual shoot and large (field scales by comparing consecutive pairs of sampling occasions. Four turnover categories were defined: Empty (no aphids recorded on either occasion; Colonised (aphids recorded on the second occasion but not the first; Extinction (aphids recorded on the first occasion but not the second; Stable (aphids recorded on both occasions. At the field scale, population stability soon established, but, at the small scale there was a consistently high proportion of unoccupied shoots with considerable colonisation and extinction and low stability. The redistribution of aphids within the crop at the local scale is a vulnerability which could be used to disrupt population development--by mediating exposure to ground-active natural enemies and by incurring a metabolic cost caused by the physiological demands to re-establish on a nearby host plant.

  18. Aphidius gifuensis: a promising parasitoid for biological control of two important aphid species in sweet pepper

    NARCIS (Netherlands)

    Messelink, G.J.; Bloemhard, C.M.J.; Hoogerbrugge, H.; Schelt, van J.

    2011-01-01

    The parasitoid Aphidius gifuensis is able to parasitize both the green peach aphid Myzus persicae and the foxglove aphid Aulacorthum solani in sweet pepper. In a greenhouse experiment we showed that rates of parasitism on green peach aphids alone were equal to the commonly used Aphidius colemani, bu

  19. National Plant Diagnostic Network, Taxonomic training videos: Aphids under the microscope - overview

    Science.gov (United States)

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This training video provides provides an overview of general aphid morphology by using a compound microscope. The narrator discusses and highlights structures on the aphid that are important to make a species identification....

  20. National Plant Diagnostic Network, Taxonomic training videos: Introduction to AphID

    Science.gov (United States)

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides visual instruction on the use of the expert system, AphID, for aphid examination and identification. The video demonstrates the use of different training modules that allow the user to gain familiarity wi...

  1. Predicting the occurrence of alate aphids in Brassicaceae

    Directory of Open Access Journals (Sweden)

    Francisco Jorge Cividanes

    2012-04-01

    Full Text Available The objective of this work was to predict the occurrence of alates of Brevicoryne brassicae, Lipaphis erysimi, and Myzus persicae (Hemiptera, Aphididae in Brassicaceae. The alate aphids were collected in yellow water traps from July 1997 to August 2005. Aphid population peaks were predicted using a degree‑day model. The meteorological factors, temperature, air relative humidity, rainfall, and sunshine hours, were used to provide precision indexes to evaluate the best predictor for the date of the first capture of alate aphids by the traps. The degree‑day model indicated that the peak population of the evaluated aphid species can be predicted using one of the following biofix dates: January 1st, June 1st, and the date of the first capture of the alate aphid species by the yellow water traps. The best predictor of B. brassicae occurrence is the number of days with minimum temperature >15°C, and of L. erysimi and M. persicae, the number of days with rainfall occurrence.

  2. Functional genomics of Buchnera and the ecology of aphid hosts.

    Science.gov (United States)

    Moran, Nancy A; Degnan, Patrick H

    2006-04-01

    In many animal groups, mutualistic bacterial symbionts play a central role in host ecology, by provisioning rare nutrients and thus enabling specialization on restricted diets. Among such symbionts, genomic studies are most advanced for Buchnera, the obligate symbiont of aphids, which feed on phloem sap. The contents of the highly reduced Buchnera genomes have verified its role in aphid nutrition. Comparisons of Buchnera gene sets indicate ongoing, irreversible gene losses that are expected to affect aphid nutritional needs. Furthermore, almost all regulatory genes have been eliminated, raising the question of whether and how gene expression responds to environmental change. Microarray studies on genome-wide expression indicate that Buchnera has evolved some constitutive changes in gene expression: homologues of heat stress genes have elevated transcript levels in Buchnera (relative to other bacteria) even in the absence of stress. Additionally, the microarray results indicate that responses to heat stress and to amino acid availability are both few and modest. Observed responses are consistent with control by the few ancestral regulators retained in the genome. Initial studies on the role of host genes in mediating the symbiosis reveal distinctive expression patterns in host cells harbouring Buchnera. In the near future, a complete genome of pea aphid will accelerate progress in understanding the functional integration of aphid and Buchnera genomes. Although information for other insect symbioses is relatively limited, studies on symbionts of carpenter ants and tsetse flies indicate many similarities to Buchnera. PMID:16626452

  3. Relationship of soybean aphid (Hemiptera: Aphididae) to soybean plant nutrients, landscape structure, and natural enemies.

    Science.gov (United States)

    Noma, Takuji; Gratton, Claudio; Colunga-Garcia, Manuel; Brewer, Michael J; Mueller, Emily E; Wyckhuys, Kris A G; Heimpel, George E; O'Neal, Matthew E

    2010-02-01

    In the north central United States, populations of the exotic soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), are highly variable across space, complicating effective aphid management. In this study we examined relationships of plant nutrients, landscape structure, and natural enemies with soybean aphid abundance across Iowa, Michigan, Minnesota, and Wisconsin, representing the range of conditions where soybean aphid outbreaks have occurred since its introduction. We sampled soybean aphid and its natural enemies, quantified vegetation land cover and measured soybean nutrients (potassium [K] and nitrogen [N]) in 26 soybean sites in 2005 and 2006. Multiple regression models found that aphid abundance was negatively associated with leaf K content in 2005, whereas it was negatively associated with habitat diversity (Simpson's index) and positively associated with leaf N content in 2006. These variables accounted for 25 and 27% of aphid variability in 2005 and 2006, respectively, suggesting that other sources of variability are also important. In addition, K content of soybean plants decreased with increasing prevalence of corn-soybean cropland in 2005, suggesting that landscapes that have a high intensification of agriculture (as indexed by increasing corn and soybean) are more likely to have higher aphid numbers. Soybean aphid natural enemies, 26 species of predators and parasitoids, was positively related to aphid abundance; however, enemy-to-aphid abundance ratios were inversely related to aphid density, suggesting that soybean aphids are able to escape control by resident natural enemies. Overall, soybean aphid abundance was most associated with soybean leaf chemistry and landscape heterogeneity. Agronomic options that can ameliorate K deficiency and maintaining heterogeneity in the landscape may reduce aphid risk.

  4. Virulent Diuraphis noxia Aphids Over-Express Calcium Signaling Proteins to Overcome Defenses of Aphid-Resistant Wheat Plants.

    Science.gov (United States)

    Sinha, Deepak K; Chandran, Predeesh; Timm, Alicia E; Aguirre-Rojas, Lina; Smith, C Michael

    2016-01-01

    The Russian wheat aphid, Diuraphis noxia, an invasive phytotoxic pest of wheat, Triticum aestivum, and barley, Hordeum vulgare, causes huge economic losses in Africa, South America, and North America. Most acceptable and ecologically beneficial aphid management strategies include selection and breeding of D. noxia-resistant varieties, and numerous D. noxia resistance genes have been identified in T. aestivum and H. vulgare. North American D. noxia biotype 1 is avirulent to T. aestivum varieties possessing Dn4 or Dn7 genes, while biotype 2 is virulent to Dn4 and avirulent to Dn7. The current investigation utilized next-generation RNAseq technology to reveal that biotype 2 over expresses proteins involved in calcium signaling, which activates phosphoinositide (PI) metabolism. Calcium signaling proteins comprised 36% of all transcripts identified in the two D. noxia biotypes. Depending on plant resistance gene-aphid biotype interaction, additional transcript groups included those involved in tissue growth; defense and stress response; zinc ion and related cofactor binding; and apoptosis. Activation of enzymes involved in PI metabolism by D. noxia biotype 2 aphids allows depletion of plant calcium that normally blocks aphid feeding sites in phloem sieve elements and enables successful, continuous feeding on plants resistant to avirulent biotype 1. Inhibition of the key enzyme phospholipase C significantly reduced biotype 2 salivation into phloem and phloem sap ingestion.

  5. Virulent Diuraphis noxia Aphids Over-Express Calcium Signaling Proteins to Overcome Defenses of Aphid-Resistant Wheat Plants.

    Directory of Open Access Journals (Sweden)

    Deepak K Sinha

    Full Text Available The Russian wheat aphid, Diuraphis noxia, an invasive phytotoxic pest of wheat, Triticum aestivum, and barley, Hordeum vulgare, causes huge economic losses in Africa, South America, and North America. Most acceptable and ecologically beneficial aphid management strategies include selection and breeding of D. noxia-resistant varieties, and numerous D. noxia resistance genes have been identified in T. aestivum and H. vulgare. North American D. noxia biotype 1 is avirulent to T. aestivum varieties possessing Dn4 or Dn7 genes, while biotype 2 is virulent to Dn4 and avirulent to Dn7. The current investigation utilized next-generation RNAseq technology to reveal that biotype 2 over expresses proteins involved in calcium signaling, which activates phosphoinositide (PI metabolism. Calcium signaling proteins comprised 36% of all transcripts identified in the two D. noxia biotypes. Depending on plant resistance gene-aphid biotype interaction, additional transcript groups included those involved in tissue growth; defense and stress response; zinc ion and related cofactor binding; and apoptosis. Activation of enzymes involved in PI metabolism by D. noxia biotype 2 aphids allows depletion of plant calcium that normally blocks aphid feeding sites in phloem sieve elements and enables successful, continuous feeding on plants resistant to avirulent biotype 1. Inhibition of the key enzyme phospholipase C significantly reduced biotype 2 salivation into phloem and phloem sap ingestion.

  6. Virulent Diuraphis noxia Aphids Over-Express Calcium Signaling Proteins to Overcome Defenses of Aphid-Resistant Wheat Plants.

    Science.gov (United States)

    Sinha, Deepak K; Chandran, Predeesh; Timm, Alicia E; Aguirre-Rojas, Lina; Smith, C Michael

    2016-01-01

    The Russian wheat aphid, Diuraphis noxia, an invasive phytotoxic pest of wheat, Triticum aestivum, and barley, Hordeum vulgare, causes huge economic losses in Africa, South America, and North America. Most acceptable and ecologically beneficial aphid management strategies include selection and breeding of D. noxia-resistant varieties, and numerous D. noxia resistance genes have been identified in T. aestivum and H. vulgare. North American D. noxia biotype 1 is avirulent to T. aestivum varieties possessing Dn4 or Dn7 genes, while biotype 2 is virulent to Dn4 and avirulent to Dn7. The current investigation utilized next-generation RNAseq technology to reveal that biotype 2 over expresses proteins involved in calcium signaling, which activates phosphoinositide (PI) metabolism. Calcium signaling proteins comprised 36% of all transcripts identified in the two D. noxia biotypes. Depending on plant resistance gene-aphid biotype interaction, additional transcript groups included those involved in tissue growth; defense and stress response; zinc ion and related cofactor binding; and apoptosis. Activation of enzymes involved in PI metabolism by D. noxia biotype 2 aphids allows depletion of plant calcium that normally blocks aphid feeding sites in phloem sieve elements and enables successful, continuous feeding on plants resistant to avirulent biotype 1. Inhibition of the key enzyme phospholipase C significantly reduced biotype 2 salivation into phloem and phloem sap ingestion. PMID:26815857

  7. Evaluation of SRAP markers for mapping of Pisum sativum L.

    Directory of Open Access Journals (Sweden)

    María Fernanda Guindon

    2016-09-01

    Full Text Available Linkage maps have become important tools for genetic studies. With the aim of evaluating the SRAP (sequence-related amplified polymorphism technique for linkage mapping in Pisum sativum L., a F2 mapping population derived from an initial cross between cvs. DDR11 and Zav25 was generated. A total of 25 SRAP primer combinations were evaluated in 45 F2 plants and both parental lines, generating 208 polymorphic bands/markers. The markers were analyzed by the chi-square goodness-of-fit test to check the expected Mendelian segregation ratio. The resulting linkage map consists of 112 genetic markers distributed in 7 linkage groups (LGs, covering a total of 528.8 cM. The length of the LGs ranged from 47.6 to 144.3 cM (mean 75.54 cM, with 9 to 34 markers. The linkage map developed in this study indicates that the SRAP marker system could be applied to mapping studies of pea.

  8. Burdock fructooligosaccharide induces stomatal closure in Pisum sativum.

    Science.gov (United States)

    Guo, Yanling; Guo, Moran; Zhao, Wenlu; Chen, Kaoshan; Zhang, Pengying

    2013-09-12

    Burdock fructooligosaccharide (BFO) isolated from the root tissue of Arctium lappa is a reserve carbohydrate that can induce resistance against a number of plant diseases. Stomatal closure is a part of plant innate immune response to restrict bacterial invasion. In this study, the effects of BFO on stomata movement in Pisum sativum and the possible mechanisms were studied with abscisic acid (ABA) as a positive control. The results showed that BFO could induce stomatal closure accompanied by ROS and NO production, as is the case with ABA. BFO-induced stomatal closure was inhibited by pre-treatment with L-NAME (N(G)-nitro-L-arginine methyl ester, hydrochloride; nitric oxide synthase inhibitor) and catalase (hydrogen peroxide scavenger). Exogenous catalase completely restricted BFO-induced production of ROS and NO in guard cells. In contrast, L-NAME prevented the rise in NO levels but only partially restricted the ROS production. These results indicate that BFO-induced stomatal closure is mediated by ROS and ROS-dependent NO production.

  9. Transient protein expression in three Pisum sativum (green pea) varieties.

    Science.gov (United States)

    Green, Brian J; Fujiki, Masaaki; Mett, Valentina; Kaczmarczyk, Jon; Shamloul, Moneim; Musiychuk, Konstantin; Underkoffler, Susan; Yusibov, Vidadi; Mett, Vadim

    2009-02-01

    The expression of proteins in plants both transiently and via permanently transformed lines has been demonstrated by a number of groups. Transient plant expression systems, due to high expression levels and speed of production, show greater promise for the manufacturing of biopharmaceuticals when compared to permanent transformants. Expression vectors based on a tobacco mosaic virus (TMV) are the most commonly utilized and the primary plant used, Nicotiana benthamiana, has demonstrated the ability to express a wide range of proteins at levels amenable to purification. N. benthamiana has two limitations for its use; one is its relatively slow growth, and the other is its low biomass. To address these limitations we screened a number of legumes for transient protein expression. Using the alfalfa mosaic virus (AMV) and the cucumber mosaic virus (CMV) vectors, delivered via Agrobacterium, we were able to identify three Pisum sativum varieties that demonstrated protein expression transiently. Expression levels of 420 +/- 26.24 mg GFP/kgFW in the green pea variety speckled pea were achieved. We were also able to express three therapeutic proteins indicating promise for this system in the production of biopharmaceuticals. PMID:19156736

  10. Burdock fructooligosaccharide induces stomatal closure in Pisum sativum.

    Science.gov (United States)

    Guo, Yanling; Guo, Moran; Zhao, Wenlu; Chen, Kaoshan; Zhang, Pengying

    2013-09-12

    Burdock fructooligosaccharide (BFO) isolated from the root tissue of Arctium lappa is a reserve carbohydrate that can induce resistance against a number of plant diseases. Stomatal closure is a part of plant innate immune response to restrict bacterial invasion. In this study, the effects of BFO on stomata movement in Pisum sativum and the possible mechanisms were studied with abscisic acid (ABA) as a positive control. The results showed that BFO could induce stomatal closure accompanied by ROS and NO production, as is the case with ABA. BFO-induced stomatal closure was inhibited by pre-treatment with L-NAME (N(G)-nitro-L-arginine methyl ester, hydrochloride; nitric oxide synthase inhibitor) and catalase (hydrogen peroxide scavenger). Exogenous catalase completely restricted BFO-induced production of ROS and NO in guard cells. In contrast, L-NAME prevented the rise in NO levels but only partially restricted the ROS production. These results indicate that BFO-induced stomatal closure is mediated by ROS and ROS-dependent NO production. PMID:23911508

  11. Review of the health benefits of peas (Pisum sativum L.).

    Science.gov (United States)

    Dahl, Wendy J; Foster, Lauren M; Tyler, Robert T

    2012-08-01

    Pulses, including peas, have long been important components of the human diet due to their content of starch, protein and other nutrients. More recently, the health benefits other than nutrition associated with pulse consumption have attracted much interest. The focus of the present review paper is the demonstrated and potential health benefits associated with the consumption of peas, Pisum sativum L., specifically green and yellow cotyledon dry peas, also known as smooth peas or field peas. These health benefits derive mainly from the concentration and properties of starch, protein, fibre, vitamins, minerals and phytochemicals in peas. Fibre from the seed coat and the cell walls of the cotyledon contributes to gastrointestinal function and health, and reduces the digestibility of starch in peas. The intermediate amylose content of pea starch also contributes to its lower glycaemic index and reduced starch digestibility. Pea protein, when hydrolysed, may yield peptides with bioactivities, including angiotensin I-converting enzyme inhibitor activity and antioxidant activity. The vitamin and mineral contents of peas may play important roles in the prevention of deficiency-related diseases, specifically those related to deficiencies of Se or folate. Peas contain a variety of phytochemicals once thought of only as antinutritive factors. These include polyphenolics, in coloured seed coat types in particular, which may have antioxidant and anticarcinogenic activity, saponins which may exhibit hypocholesterolaemic and anticarcinogenic activity, and galactose oligosaccharides which may exert beneficial prebiotic effects in the large intestine. PMID:22916813

  12. Processing Pisum sativum seed storage protein precursors in vitro

    Institute of Scientific and Technical Information of China (English)

    YANGLIJUN; CDOMONEY; 等

    1990-01-01

    The profile of polypeptides separated by SDS-PAGE from seed of major crop species such as pea(Pisum sativum) is complex,resulting from cleavage (processing) of precursors expressed from multiple copies of genes encoding vicilin and legumin,the major storage globulins.Translation in vitro of mRNAs hybridselected from mid-maturation pea seed RNAs by defined vicilin and legumin cDNA clones provided precursor molecules that were cleaved in vitro by a cell-free protease extract obtained from similar stage seed;the derived polypeptides were of comparable sizes to those observed in vivo.The feasibility of transcribing mRNA in vitro from a cDNA clone and cleavage in vitro of the derived translation products was established for a legumin clone,providing a method for determining polypeptide products of an expressed sequence.This approach will also be useful for characterising cleavage site requirements since modifications an readily be introduced at the DNA level.

  13. Fertility improvement in pea (Pisum sativum L.) autotetraploids -mutation breeding

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, H.; Mercykuty, V.C.; Srivastava, C.P. [Banaras Hindu Univ., Varanasi (India). Dept. of Genetics and Plant Breeding

    1995-12-31

    C{sub 2} seeds of autotetraploids (colchicine-induced) of two diverse genotypes, T 163 and 5064-S, of pea (Pisum sativum L.) and their corresponding diploids were irradiated with 10 kR gamma-ray. Autotetraploids showed a high seed-sterility as compared to diploids. Seed fertility increased in M{sub 2} as compared to M{sub 1}. Both quadrivalent and bivalent frequencies decreased in the M{sub 1} generation of autotetraploids in relation to their respective controls. However, a positive shift in the mean bivalent formation was noted at the cost of other configurations in C{sub 3}-M{sub 2} with respect to C{sub 2}-M{sub 1} and varied with the genotype. In the M{sub 2} generation of autotetraploids, the variability was relatively higher for the number of pods per plant and seed yield per plant. Although the mean values for pods per plant, number of seeds per pod and seed yield per plant remained more or less parallel in autotetraploids in M{sub 1} and M{sub 2} generations, there was an increase in the upper range limit probably due to micromutation for these characters in M{sub 2}. (author). 15 refs, 2 tabs.

  14. Infestation and natural parasitism of aphids in single and mixed pastures of black oats and ryegrass

    Directory of Open Access Journals (Sweden)

    Vinícius Soares Sturza

    2012-09-01

    Full Text Available Some species of aphids are major pests on cereal crops and grass pastures. Usually these pests are not adequately controlled in pasture lands that become sources of aphid infestations to cereal crops. The dynamics of aphids and the incidence of natural enemies are less known in pasture systems than in cereal fields. The objective of this work was to assess the aphid infestation and natural aphid parasitism in different pasture composition. Three hypotheses were tested: 1- the aphid species composition in pastures may vary according to the cereal species in the field; 2- the mixture of two plant species can modify the amount and diversity of aphids; 3- the plant species composition of pasture fields influences the parasitism of aphids. Empirical data were obtained from three Poaceae fields: black oats (Avena strigosa L., ryegrass (Lolium multiflorum L., and a mixed field of black oats and ryegrass. The most abundant aphid species was Rhopalosiphum padi followed by Sitobion avenae. Plant species composition increases the amount and the parasitism rates of aphids. The mixture of heavily infested black oats with a poorly infested ryegrass resulted in reduction of aphid infestation in comparison with heavily-infested single plant species field. This is possible because the conditions are favorable for the development of parasitoid populations. Aphidius colemani was the main parasitoid found in these areas.

  15. Olfactory responses of Aphidius gifuensis to odors of host plants and aphid-plant complexes

    Institute of Scientific and Technical Information of China (English)

    Song Yang; Rui Xu; Shuo-Yuan Yang; Rong-Ping Kuang

    2009-01-01

    The olfactory responses of Aphidius gifuensis to odors from two host plants (Nicotiana tabacum and Brassica napus ssp.) and their complexes with different infestation levels of two host aphids (Myzus persicae and Lipaphis erysimi) were respectively examined in an olfactometer. The results showed that female A. gifuensis did not respond to odors of undamaged or mechanically damaged host plants, but significantly responded to odors of aphid/plant complexes. Moreover, A. gifuensis responded significantly to odors of both M persicae and L. erysimi/plant complexes when host plants were infested by high levels of aphids, suggesting that quantity of aphid-induced volatiles could be important for attracting A. gifuensis. When tested between aphid/plant complexes, A. gifuensis did not show its preference for either complex. The efficiency of A. gifuensis against aphids in open fields potentially could be improved by using its olfactory response to aphid/plant complexes.

  16. Age-dependent variation in membrane lipid synthesis in leaves of garden pea (Pisum sativum L.)

    DEFF Research Database (Denmark)

    Hellgren, Lars; Sandelius, A.S.

    2001-01-01

    To study membrane lipid synthesis during the lifespan of a dicotyledon leaf, the second oldest leaf of 10-40-d-old plants of garden pea (Pisum sativum L.) was labelled with [1-C- 14]acetate and the distribution of radioactivity between the major membrane lipids was followed for 3 d. In the expand......To study membrane lipid synthesis during the lifespan of a dicotyledon leaf, the second oldest leaf of 10-40-d-old plants of garden pea (Pisum sativum L.) was labelled with [1-C- 14]acetate and the distribution of radioactivity between the major membrane lipids was followed for 3 d...

  17. The role of malate in the synthesis of glutamate in Pisum arvense roots

    Directory of Open Access Journals (Sweden)

    Genowefa Kubik-Dorosz

    2014-02-01

    Full Text Available The in vivo and in vitro activities of NADH-dependent glutamate synthase in excised Pisum arvense roots increased several-fold under the influence of malate while pyruvate oxaloacctate. citrate and succinate inhibited this entyme. The plastids isolated from Pisum arvense root,. ahen incubated with glutamine and α-ketoglutarate, released glutamate into the medium Malate clearly stimulated this process. Albizziin (25 mM completely reduced the presence of glutamate in the incubation mixture. These results indicate that reduced pyridine nucleotides arising in P. arvense root plastids during oxidation of malic acid may constitute the indispensable source of electrons for glutamic acid synthesis.

  18. Pea (Pisum sativum L. in the Genomic Era

    Directory of Open Access Journals (Sweden)

    Robert J. Redden

    2012-04-01

    Full Text Available Pea (Pisum sativum L. was the original model organism used in Mendel’s discovery (1866 of the laws of inheritance, making it the foundation of modern plant genetics. However, subsequent progress in pea genomics has lagged behind many other plant species. Although the size and repetitive nature of the pea genome has so far restricted its sequencing, comprehensive genomic and post genomic resources already exist. These include BAC libraries, several types of molecular marker sets, both transcriptome and proteome datasets and mutant populations for reverse genetics. The availability of the full genome sequences of three legume species has offered significant opportunities for genome wide comparison revealing synteny and co-linearity to pea. A combination of a candidate gene and colinearity approach has successfully led to the identification of genes underlying agronomically important traits including virus resistances and plant architecture. Some of this knowledge has already been applied to marker assisted selection (MAS programs, increasing precision and shortening the breeding cycle. Yet, complete translation of marker discovery to pea breeding is still to be achieved. Molecular analysis of pea collections has shown that although substantial variation is present within the cultivated genepool, wild material offers the possibility to incorporate novel traits that may have been inadvertently eliminated. Association mapping analysis of diverse pea germplasm promises to identify genetic variation related to desirable agronomic traits, which are historically difficult to breed for in a traditional manner. The availability of high throughput ‘omics’ methodologies offers great promise for the development of novel, highly accurate selective breeding tools for improved pea genotypes that are sustainable under current and future climates and farming systems.

  19. Inventory and assessment of foliar natural enemies of the soybean aphid (Hemiptera: Aphididae) in South Dakota.

    Science.gov (United States)

    Hesler, Louis S

    2014-06-01

    Soybean aphid (Aphis glycines Matsumura) (Hemiptera: Aphididae) is a major pest of soybean in northern production regions of North America, and insecticides have been the primary management approach while alternative methods are developed. Knowledge of arthropod natural enemies and their impact on soybean aphid is critical for developing biological control as a management tool. Soybean is a major field crop in South Dakota, but information about its natural enemies and their impact on soybean aphid is lacking. Thus, this study was conducted in field plots in eastern South Dakota during July and August of 2004 and 2005 to characterize foliar-dwelling, arthropod natural enemies of soybean aphid, and it used exclusion techniques to determine impact of natural enemies and ants (Hymenoptera: Formicidae) on soybean aphid densities. In open field plots, weekly soybean aphid densities reached a plateau of several hundred aphids per plant in 2004, and peaked at roughly 400 aphids per plant in 2005. Despite these densities, a relatively high frequency of aphid-infested plants lacked arthropod natural enemies. Lady beetles (Coleoptera: Coccinellidae) were most abundant, peaking at 90 and 52% of all natural enemies sampled in respective years, and Harmonia axyridis Pallas was the most abundant lady beetle. Green lacewings (Neuroptera: Chrysopidae) were abundant in 2005, due mainly to large numbers of their eggs. Abundances of arachnids and coccinellid larvae correlated with soybean aphid densities each year, and chrysopid egg abundance was correlated with aphid density in 2005. Three-week cage treatments of artificially infested soybean plants in 2004 showed that noncaged plants had fewer soybean aphids than caged plants, but abundance of soybean aphid did not differ among open cages and ones that provided partial or total exclusion of natural enemies. In 2005, plants within open cages had fewer soybean aphids than those within cages that excluded natural enemies, and aphid

  20. The endosymbiont Arsenophonus is widespread in soybean aphid, Aphis glycines, but does not provide protection from parasitoids or a fungal pathogen

    Science.gov (United States)

    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., ...

  1. First report of Pandora neoaphidis resting spore formation in vivo in aphid hosts

    DEFF Research Database (Denmark)

    Clara Scorsetti, Ana; Jensen, Annette Bruun; Lopez Lastra, Claudia;

    2012-01-01

    The entomopathogenic fungus Pandora neoaphidis is a recognized pathogen of aphids, causes natural epizootics in aphid populations, and interacts and competes with aphid predators and parasitoids. Survival of entomophthoralean fungi in periods of unsuitable weather conditions or lack of appropriat...

  2. High susceptibility of Bt maize to aphids enhances the performance of parasitoids of lepidopteran pests.

    Directory of Open Access Journals (Sweden)

    Cristina A Faria

    Full Text Available Concerns about possible undesired environmental effects of transgenic crops have prompted numerous evaluations of such crops. So-called Bt crops receive particular attention because they carry bacteria-derived genes coding for insecticidal proteins that might negatively affect non-target arthropods. Here we show a remarkable positive effect of Bt maize on the performance of the corn leaf aphid Rhopalosiphum maidis, which in turn enhanced the performance of parasitic wasps that feed on aphid honeydew. Within five out of six pairs that were evaluated, transgenic maize lines were significantly more susceptible to aphids than their near-isogenic equivalents, with the remaining pair being equally susceptible. The aphids feed from the phloem sieve element content and analyses of this sap in selected maize lines revealed marginally, but significantly higher amino acid levels in Bt maize, which might partially explain the observed increased aphid performance. Larger colony densities of aphids on Bt plants resulted in an increased production of honeydew that can be used as food by beneficial insects. Indeed, Cotesia marginiventris, a parasitoid of lepidopteran pests, lived longer and parasitized more pest caterpillars in the presence of aphid-infested Bt maize than in the presence of aphid-infested isogenic maize. Hence, depending on aphid pest thresholds, the observed increased susceptibility of Bt maize to aphids may be either a welcome or an undesirable side effect.

  3. Associations of wheat with pea can reduce aphid infestations.

    Science.gov (United States)

    Lopes, T; Bodson, B; Francis, F

    2015-06-01

    Increasing plant diversity within crops can be beneficial for pest control. In this field study, the effects of two wheat and pea associations (mixed cropping and strip cropping) on aphid populations were compared with pure stands of both crops by observations on tillers and plants. Pea was more susceptible to infestations than wheat. As expected, the density of aphid colonies was significantly higher in pure stands during the main occurrence periods, compared with associations. Additionally, flying beneficials, such as not only aphidophagous adult ladybirds but also parasitoid, hoverfly and lacewing species that feed on aphids at the larval stage, were monitored using yellow pan traps. At specific times of the sampling season, ladybirds and hoverflies were significantly more abundant in the pure stand of pea and wheat, respectively, compared with associations. Few parasitoids and lacewings were trapped. This study showed that increasing plant diversity within crops by associating cultivated species can reduce aphid infestations, since host plants are more difficult to locate. However, additional methods are needed to attract more efficiently adult beneficials into wheat and pea associations. PMID:26013274

  4. Sugarcane aphid resistance in sorghum and a host range

    Science.gov (United States)

    The sugarcane aphid (SCA), Melanaphis sacchari, has been present in the United States primarily on sugarcane in Florida, Hawaii, and Louisiana until 2013 where it was found on grain sorghum near Beaumont, Texas. Since 2013, the SCA has been rapidly spreading and overwintering. Depending on the plant...

  5. Sugarcane aphid in Oklahoma: Responding to a new pest

    Science.gov (United States)

    The sugarcane aphid (SCA) was first found in Oklahoma in 2013, and quickly became a major threat to grain sorghum production. Scientists at Oklahoma State University and the USDA's Wheat, Peanut and Other Field Crops Research Lab in Stillwater, working with cooperators in other sorghum producing st...

  6. Catalog of the Aphid Genera Described from the New World

    Science.gov (United States)

    This manuscript presents a synthesis and catalogue of the genera of New World aphids (sensu stricto) from 1758 to 2004. It includes information on 215 generic and subgeneric names, type localities, bibliographic information, etymology, as well as synonymic and other nomenclatural data. Two nomencl...

  7. Differential effects of weather and natural enemies on coexisting aphid populations.

    Science.gov (United States)

    Alyokhin, Andrei; Drummond, Francis A; Sewell, Gary; Storch, Richard H

    2011-06-01

    Study of mechanisms responsible for regulating populations of living organisms is essential for a better comprehension of the structure of biological communities and evolutionary forces in nature. Aphids (Hemiptera: Sternorrhyncha) comprise a large and economically important group of phytophagous insects distributed worldwide. Previous studies determined that density-dependent mechanisms play an important role in regulating their populations. However, only a few of those studies identified specific factors responsible for the observed regulation. Time series data used in this study originated from the untreated control plots that were a part of potato (Solanum tuberosum L.) insecticide trials in northern Maine from 1971 to 2004. The data set contained information on population densities of three potato-colonizing aphid species (buckthorn aphid, Aphis nasturtii; potato aphid, Macrosiphum euphorbiae; and green peach aphid, Myzus persicae) and their natural enemies. We used path analysis to explore effects of weather and natural enemies on the intrinsic growth rates of aphid populations. Weather factors considered in our analyses contributed to the regulation of aphid populations, either directly or through natural enemies. However, direct weather effects were in most cases detectable only at P ≤ 0.10. Potato aphids were negatively affected by both fungal disease and predators, although buckthorn aphids were negatively affected by predators only. Parasitoids did not have a noticeable effect on the growth of any of the three aphid species. Growth of green peach aphid populations was negatively influenced by interspecific interactions with the other two aphid species. Differential population regulation mechanisms detected in the current study might at least partially explain coexistence of three ecologically similar aphid species sharing the same host plant.

  8. [Population dynamics and control techniques of aphids on honeysuckle].

    Science.gov (United States)

    Sun, Ying; Xue, Ming; Zhang, Xiao; Zhao, Hai-Peng; Li, Zhao-Xia

    2013-11-01

    The objective of this study is to define the population dynamics of Semiaphis heraclei in the main-producing district of Lonicera japonica in Shandong, and screen for highly efficient, safety control technique. Through fixed field investigation, we tested the toxicity of eight kinds of insecticides by using dipping methods, and carried out the field experiment. The results showed that the aphids' emergence peak appeared in May. The aphids on the Sijihua variety of L. japonica was more susceptible and the peak was also seven days earlier than Damao variety of L. japonica. The aphid populations on Sijihua were 1 fold than those on the Daomao in happened peak. Comparing the eight kinds of insecticides, the LC50 of lambda-cyhaothrin, abamectin, imidacloprid and pyrethrin to wingless aphids were 1.494, 1.690, 2.840, 2.861 mg x L(-1), respectively, whose toxicity were higher, the toxicity of matrine, pymetrozine and azadirachtin were also high. The field efficacy trials indicated that during the period of aphids occurred, 25% imidacloprid wettable powder, 1.8% abamectin missible oil, 2.5% lambda-cyhaothrin missible oil, 25% pymetrozine wettable powder, 5% pyrethrin missible oil, 1% matrine water aqua were sprayed at concentrations of 20,000, 2,000, 2,500, 5,000, 500 and 50 times, respectively,the control effect achieved 91.69%, 98.90%, 96.18%, 95.06%, 99.24%, 90.10%, respectively, after 5 days. During the growing period of L. japonica in spring, application of thiamethoxam, thiacloprid, pymetrozine and imidacloprid, all of the control effect against aphids achieved above 98.88% after 50 days. The result indicated that May was the S. heraclei Takahashi's emergence peak in Pingyi, Shandong. The efficient safety and environmentally friendly insecticides by spraying and systemic insecticide of pymetrozine and imidacloprid by root application were all efficient controlled aphids. These insecticides were long for controlling S. heraclei Takahashi and worthy of being widely

  9. High throughput phenotyping for aphid resistance in large plant collections

    Directory of Open Access Journals (Sweden)

    Chen Xi

    2012-08-01

    Full Text Available Abstract Background Phloem-feeding insects are among the most devastating pests worldwide. They not only cause damage by feeding from the phloem, thereby depleting the plant from photo-assimilates, but also by vectoring viruses. Until now, the main way to prevent such problems is the frequent use of insecticides. Applying resistant varieties would be a more environmental friendly and sustainable solution. For this, resistant sources need to be identified first. Up to now there were no methods suitable for high throughput phenotyping of plant germplasm to identify sources of resistance towards phloem-feeding insects. Results In this paper we present a high throughput screening system to identify plants with an increased resistance against aphids. Its versatility is demonstrated using an Arabidopsis thaliana activation tag mutant line collection. This system consists of the green peach aphid Myzus persicae (Sulzer and the circulative virus Turnip yellows virus (TuYV. In an initial screening, with one plant representing one mutant line, 13 virus-free mutant lines were identified by ELISA. Using seeds produced from these lines, the putative candidates were re-evaluated and characterized, resulting in nine lines with increased resistance towards the aphid. Conclusions This M. persicae-TuYV screening system is an efficient, reliable and quick procedure to identify among thousands of mutated lines those resistant to aphids. In our study, nine mutant lines with increased resistance against the aphid were selected among 5160 mutant lines in just 5 months by one person. The system can be extended to other phloem-feeding insects and circulative viruses to identify insect resistant sources from several collections, including for example genebanks and artificially prepared mutant collections.

  10. Differential reactions of soybean isolines with combinations of aphid resistance genes Rag1, Rag2, and Rag3 to four soybean aphid biotypes

    Science.gov (United States)

    With the discovery of the soybean aphid (Aphis glycines Matsumura) as a devastating insect pest of soybean (Glycine max (L.) Merr.) in the United States, host resistance was recognized as an important management option. However, the identification of soybean aphid isolates exhibiting strong virulenc...

  11. Transcriptomic responses of the aphid Myzus persicae nicotianae Blackman (Hemiptera: Aphididae to insecticides: Analyses in the single Chilean clone of the tobacco aphid

    Directory of Open Access Journals (Sweden)

    Marco Cabrera-Brandt

    2014-04-01

    Full Text Available The tobacco aphid Myzus persicae nicotianae Blackman is a subspecies of the highly polyphagous and agricultural pest Myzus persicae (Sulzer. For its control, insecticide applications are widely used, but resistance to numerous molecules has been reported, displaying at least three insecticide resistance mechanisms, including: (i elevated carboxylesterases (E-Carb, (ii modification of the acetylcholinesterase (MACE, and (iii kdr and super-kdr insensitivity mutations. In Chile, populations of the tobacco aphid are characterized by the presence of a single predominant clone, which is also present in high proportions in other countries of the Americas. This aphid clone exhibits low levels of carboxylesterase activity and is kdr susceptible, but the MACE mechanism of insecticide resistance has not been studied. In order to characterize the tobacco aphid in terms of the MACE mechanism and to identify a preliminary group of aphid genes putatively involved in insecticide resistance, a cDNA microarray was used to study the transcriptomic responses when aphids are sprayed with a carbamate insecticide. The single Chilean clone of the tobacco aphid was characterized as MACE susceptible, but we found 38 transcripts significantly regulated by insecticide exposure (13 up- and 25 down-regulated genes. The expression of six of them was validated by qRT-PCR experiments at several time points (6, 12, 18, 24, 30, 36, and 42 h after insecticide application. This mutational and transcriptomic characterization of the tobacco aphid responding to insecticide spray opens new hypotheses in the understanding of the molecular mechanisms underlying insecticide resistance.

  12. Physiological responses of pisum sativum plant to exogenous aba application under drought conditions

    International Nuclear Information System (INIS)

    This study was carried out to investigate the possibility of using foliar ABA application with different concentrations (50,100 and 150 meu g/L-1) in order to decrease the adverse effect of water-deficit stress. The main parameters of interest were; growth parameters; endogenous phytohormones, proline; pigments contents; number and shape of stomata; minerals concentrations; isozymes; and SDS -PAGE protein profile in Pisum sativum plant at 36 days under drought and ABA treatments. The results showed that ABA reduces the reduction in both fresh and dry weights shoot and root of Pisum induced by drought stress. Proline content was increased in response to drought and ABA treatments. Water-stress caused significant reduction in Chl. a, b, whereas application of ABA significantly increased in total chlorohpyll. Water stress significantly decreased IAA, GA concentrations and increased ABA level in leaves than these of the control. ABA treatment partially overcame the decrease in IAA and GA contents. Water stress and ABA increased the activity of (POD) and (ACP) enzymes in Pisum plants. Proteins profile of Pisum sativum in shoot revealed qualitative and quantitative changes, also appearance or disappearance of some bands. After 54 days the yield harvested and total carbohydrates and SDS -PAGE protein profile in seed were investigated. The data showed that total carbohydrates contents were significantly decreased in plant under drought and ABA partially alleviate the adverse effect of water-deficit stress. (author)

  13. Effect of TDZ on plant regeneration from mature seeds in pea (Pisum sativum)

    NARCIS (Netherlands)

    Shan, Zhihui; Tzitzikas, E.; Raemakers, C.J.J.M.; Zhengqiang, M.; Visser, R.G.F.

    2009-01-01

    Pea (Pisum sativum L. cv. Espace) seeds directly cultured on thidiazuron (TDZ)-containing medium formed high numbers of shoots. The number of shoots per seedling depended on the concentration and duration of the TDZ treatment. The best treatment was 12-wk incubation on MS medium supplemented with 4

  14. Genetic Diversity of Chinese and Global Pea (Pisum sativum L.) Collections.

    Science.gov (United States)

    Pea (Pisum sativum L.) is an important food and feed legume grown across many temperate regions of the world, especially from Asia to Europe and North America. The goal of this study was to use 30 informative pea microsatellite markers to compare genetic diversity in a global core from the USDA and ...

  15. Danish Rhizobium leguminosarum strains nodulating ‘Afghanistan’ pea (Pisum sativum)

    DEFF Research Database (Denmark)

    Jensen, Erik Steen; Sørensen, Lasse Holst; Engvild, Kjeld Christensen

    1986-01-01

    A wild pea (Pisum sativum L.) native to Afghanistan normally known to be resisant to nodulation with European strains of Rhizobium leguminosarum was nodulated early and effectively in field soil in Denmark. Isolates from nodules formed effective nodules abundantly on 'Afghanistan' on reinfection...... pattern with Rhizobium leguminosarum strains isolated from a modern pea variety cultivated in the same field....

  16. Pea (Pisum sativum) Seed Production as an Assay for Reproductive Effects Due to Herbicides.

    Science.gov (United States)

    Even though herbicide drift can affect plant reproduction, current plant testing protocols emphasize effects on vegetative growth. In this study, we determined whether a short–growing season plant can indicate potential effects of herbicides on seed production. Pea (Pisum sativum...

  17. The intracellular localization of malate dehydrogenase isoenzymes in Pisum arvense roots

    Directory of Open Access Journals (Sweden)

    Genowefa Kubik-Dorosz

    2014-02-01

    Full Text Available Mitochondria and plastids were isolated from Pisum arvense root cells by sucrose density gradient centrifugation. The individual subcellular fractions so obtained were subjected to isoelectric focusing on cellulose acetate strips. Mitochondria and plastids each contained one NAD -malate dehydrogenase, while three isoenzymes were associated with the supernatant.

  18. First survey on ecological host range of aphid pathogenic fungi (Phylum Entomophthoromycota) in Tunisia

    DEFF Research Database (Denmark)

    Ben Fekih, Ibtissem; Boukhris-Bouhachem, Sonia; Allagui, Mohamed Bechir;

    2015-01-01

    Summary. The natural occurrence of fungal pathogens of aphids and their ecological host range was investigated in Tunisia from 2009 to 2012. The survey focused on aphid infesting different crops and weeds and included 10 different aphid species. Samples were collected from eight agricultural crops...... (Entomophthorales: Ancylistaceae) and Neozygites fresenii (Neozygitales: Neozygitaceae). The occurrence of entomophthoralean fungi depended on the sampling area, the bioclimatic zone, and aphid species. P. neoaphidis and E. planchoniana were the predominant pathogens infecting a wide range of aphid species whereas...... C. obscurus and N. fresenii were sporadically present on a limited number of aphid species. This study is the first survey on ecological host range of entomophthoralean fungi in Tunisia, and the first documentation of C. obscurus and N. fresenii to occur in Tunisia and Maghreb Region....

  19. Arabidopsis thaliana - Myzus persicae interaction: shaping the understanding of plant defense against phloem-feeding aphids

    Directory of Open Access Journals (Sweden)

    Joe eLouis

    2013-07-01

    Full Text Available The phloem provides a unique niche for several organisms. Aphids are a large group of Hemipteran insects that utilize stylets present in their mouthparts to pierce sieve elements and drink large volumes of phloem sap. In addition, many aphids also vector viral diseases. Myzus persicae, commonly known as the green peach aphid (GPA, is an important pest of a large variety of plants that includes Arabidopsis thaliana. This review summarizes recent studies that have exploited the compatible interaction between Arabidopsis and GPA to understand the molecular and physiological mechanisms utilized by plants to control aphid infestation, as well as genes and mechanisms that contribute to susceptibility. In addition, recent efforts to identify aphid-delivered elicitors of plant defenses and novel aphid salivary components that facilitate infestation are also discussed.

  20. Preacondicionamiento de la Semilla de Arveja (Pisum sativum L.

    Directory of Open Access Journals (Sweden)

    Henao Omar A

    1997-06-01

    Full Text Available En el Centro de Investigación "La selva ", de la Corporación Colombiana de Investigación Agropecuaria. CORPOICA, ubicado en Rionegro, Antioquia. a 2120 msnm, con una temperatura promedio de 17 °C y perteneciente a la formación ecológica Bosque Húmedo Montano Bajo, se llevó a cabo un estudio con la especie arveja (Pisum sativum L., con el fin de evaluar el efecto del tratamiento de preacondicionamiento de las semillas, conocido como humedecimiento-secado, sobre la germinación, la emergencia y el establecimiento de plantas. Adicionalmente se evaluó el procedimiento con diferentes concentraciones del fungicida sistémico benomyl, en comparación con agua destilada, buscándose reducir la pérdida de plantas durante el período de establecimiento del cultivo, y se midió el efecto de los tratamientos con y sin fungicida sobre el rendimiento, en comparación con plantas provenientes de semilla no preacondicionada. A nivel de laboratorio se encontró que el tratamiento que produjo mayor velocidad de germinación fué la imbibición hasta el 75% de peso de la semilla, con secado posterior hasta recobrar el peso inicial. Utilizando el tratamiento anterior, se halló que la adición de benomyl, en diferentes concentraciones, no afectó la velocidad de germinación ni la germinación total, incrementándose el porcentaje de plantas sanas obtenidas en comparación con el preacondicionamiento sin fungicida, con valores máximos al imbibir con una solución de benomyl al 0.1%. En el campo no se observó efecto de los tratamientos de preacondicionamiento con y sin fungicida sobre la velocidad de emergencia y la emergencia total, reduciendo los tratamientos con fungicida la incidencia de plantas muertas en forma sensible con una respuesta diferencial en rendimiento, por parte de las dos variedades estudiadas, al aplicar los diversos procedimientos de preacondicionamiento. Así, mientras que con el cultivar 'Small Sieve All Sweet ', no hubo efecto

  1. Comparative transcriptome analysis of Gossypium hirsutum L. in response to sap sucking insects: aphid and whitefly

    OpenAIRE

    Dubey, Neeraj Kumar; Goel, Ridhi; Ranjan, Alok; Idris, Asif; Singh, Sunil Kumar; Bag, Sumit K; Chandrashekar, Krishnappa; Pandey, Kapil Deo; Singh, Pradhyumna Kumar; Sawant, Samir V.

    2013-01-01

    Background Cotton (Gossypium hirsutum L.) is a major fiber crop that is grown worldwide; it faces extensive damage from sap-sucking insects, including aphids and whiteflies. Genome-wide transcriptome analysis was performed to understand the molecular details of interaction between Gossypium hirsutum L. and sap-sucking pests, namely Aphis gossypii (Aphid) and Bemisia tabacci (Whiteflies). Roche’s GS-Titanium was used to sequence transcriptomes of cotton infested with aphids and whiteflies for ...

  2. In vitro interactions of the aphid endosymbiotic SymL chaperonin with barley yellow dwarf virus.

    OpenAIRE

    Filichkin, S A; Brumfield, S; Filichkin, T P; Young, M. J.

    1997-01-01

    Barley yellow dwarf virus (BYDV)-vector relationships suggest that there are specific interactions between BYDV virions and the aphid's cellular components. However, little is known about vector factors that mediate virion recognition, cellular trafficking, and accumulation within the aphid. Symbionins are molecular chaperonins produced by intracellular endosymbiotic bacteria and are the most abundant proteins found in aphids. To elucidate the potential role of symbionins in BYDV transmission...

  3. Distribution, host plants and natural enemies of sugar beet root aphid (Pemphigus fuscicornis) In Slovakia

    OpenAIRE

    Tóth Peter; Tancik Ján I.; Tóthová Monika; Pačuta Vladimir

    2006-01-01

    During 2003-2004, field surveys were realized to observe the distribution of sugar beet aphid, Pemphigus fuscicornis (K o c h) (Sternorrhyncha Pemphigidae) in southwestern Slovakia. The research was carried out at 60 different localities with altitudes 112-220 m a. s. l. Sugar beet root aphid was recorded at 30 localities. The aphid was recorded in Slovakia for the first time, but its occurrence was predicted and symptoms and harmfulness overlooked by now. The presence of P. fuscicornis was i...

  4. Changes in the Russian Wheat Aphid (Hemiptera: Aphididae) Biotype Complex in South Africa.

    Science.gov (United States)

    Jankielsohn, Astrid

    2016-04-01

    Russian wheat aphid Diuraphis noxia (Kurdjumov) has spread from its native area in central Asia to all the major wheat-producing countries in the world to become an international wheat pest. Because the Russian wheat aphid is a serious threat to the wheat industry in South Africa, it is important to investigate the key factors involved in the distribution of Russian wheat aphid biotypes and in the changes of the Russian wheat aphid biotype complex in South Africa. There are currently four known Russian wheat aphid biotypes occurring in South Africa. Russian wheat aphid samples were collected from 2011 to 2014 during the wheat-growing season in spring and summer and these samples were screened to determine the biotype status. RWASA1 occurred predominantly in the Western Cape, while RWASA2 and RWASA3 occurred predominantly in the Eastern Free State. Following the first record of RWASA4 in 2011, this biotype was restricted to the Eastern Free State. The surveys suggest that the Russian wheat aphid bioype complex was more diverse in the Eastern Free State than in the other wheat production areas. There was also a shift in Russian wheat aphid biotype composition over time. The Russian wheat aphid biotype complex is dynamic, influenced by environmental factors such as host plants, altitude, and climate, and it can change and diversify over time causing fluctuation in populations over sites and years. This dynamic nature of the Russian wheat aphid will continue to challenge the development of Russian wheat aphid-resistant wheat cultivars in South Africa, and the continued monitoring of the biotypic and genetic structure, to determine genetic relatedness and variation in different biotypes, of Russian wheat aphid populations is important for protecting wheat.

  5. New additions and invasive aphids for Turkey’s aphidofauna (Hemiptera: Aphidoidea)

    OpenAIRE

    Şenol, Özhan; BEĞEN, Hayal AKYILDIRIM; Görür, Gazi; DEMİRTAŞ, Emin

    2015-01-01

    This study was carried out in order to determine aphid species in the Inner Western Anatolian Subregion of Turkey. Nineteen aphid species are reported as new to the Turkish aphid fauna. These species are Aphis eryngiiglomerata Bozhko, 1963; Aphis glareosae Bozhko, 1959; Capitophorus eniwanus Miyazaki, 1971; Chaitophorus indicus A.K. Ghosh, M.R. Ghosh & D.N. Raychaudhuri, 1970; Chaitophorus ramicola (Börner, 1949); Cinara indica Verma, 1970; Cinara juniperensis (Gillette & Palmer, 1925...

  6. New Additions and Invasive Aphids for Turkey’s Aphidofauna (Hemiptera: Aphidoidea)

    OpenAIRE

    Şenol, Özhan; Akyıldırım, Hayal; Görür, Gazi; Demirtaş, Emin

    2015-01-01

    This study was carried out in order to determine aphid species in the Inner Western Anatolian Subregion of Turkey. Nineteen aphid species are reported as new to the Turkish aphid fauna. These species are Aphis eryngiiglomerata Bozhko, 1963; Aphis glareosae Bozhko, 1959; Capitophorus eniwanus Miyazaki, 1971; Chaitophorus indicus A.K. Ghosh, M.R. Ghosh & D.N. Raychaudhuri, 1970; Chaitophorus ramicola (Börner, 1949); Cinara indica Verma, 1970; Cinara juniperensis (Gillette & Palmer, 1925); Cinar...

  7. Changes in the Russian Wheat Aphid (Hemiptera: Aphididae) Biotype Complex in South Africa.

    Science.gov (United States)

    Jankielsohn, Astrid

    2016-04-01

    Russian wheat aphid Diuraphis noxia (Kurdjumov) has spread from its native area in central Asia to all the major wheat-producing countries in the world to become an international wheat pest. Because the Russian wheat aphid is a serious threat to the wheat industry in South Africa, it is important to investigate the key factors involved in the distribution of Russian wheat aphid biotypes and in the changes of the Russian wheat aphid biotype complex in South Africa. There are currently four known Russian wheat aphid biotypes occurring in South Africa. Russian wheat aphid samples were collected from 2011 to 2014 during the wheat-growing season in spring and summer and these samples were screened to determine the biotype status. RWASA1 occurred predominantly in the Western Cape, while RWASA2 and RWASA3 occurred predominantly in the Eastern Free State. Following the first record of RWASA4 in 2011, this biotype was restricted to the Eastern Free State. The surveys suggest that the Russian wheat aphid bioype complex was more diverse in the Eastern Free State than in the other wheat production areas. There was also a shift in Russian wheat aphid biotype composition over time. The Russian wheat aphid biotype complex is dynamic, influenced by environmental factors such as host plants, altitude, and climate, and it can change and diversify over time causing fluctuation in populations over sites and years. This dynamic nature of the Russian wheat aphid will continue to challenge the development of Russian wheat aphid-resistant wheat cultivars in South Africa, and the continued monitoring of the biotypic and genetic structure, to determine genetic relatedness and variation in different biotypes, of Russian wheat aphid populations is important for protecting wheat. PMID:26803815

  8. Aphids (Homoptera, Aphidodea inhabiting the trees Crataegus x media Bechst. in the urban green area. Part II. Domination and frequency of aphids, their enemies and the damage caused by aphids

    Directory of Open Access Journals (Sweden)

    Aneta Sławińska

    2013-12-01

    Full Text Available The studies were conducted in Lublin in the years 1999-2001 in two sites (street and park ones on the trees Crataegus x inedia Bechst. The purpose was to determine the domination and frequency of particular aphid species, their effect on the decorative character of plants as well as the occurrence of the aphidophagous in aphid colonies. It was found out that A. pomi was the dominating species in both sites. The decorative character of the studied trees was lowered by aphids A. pomi and aphids from the genus Dysaphis. Aphids from the genus Dysaphis also caused changes in the chemical composition of the injured plant parts. The presence of predatory arthropods was observed in aphid colonies occurring on hawthorn. The most numerous of these were the larvae of Syrphidae and Coccinellidae. The culture of parasitized aphids gave numerous flights of parasitoids and hyperparasitoids. Greater number of both predators and parasitoids of I and II grades were observed in the street site as compared to the park site.

  9. Modification of non-vector aphid feeding behavior on virus-infected host plant.

    Science.gov (United States)

    Hu, Zuqing; Zhao, Huiyan; Thieme, Thomas

    2013-01-01

    Virus-infected host plants can have positive, neutral or negative effects on vector aphids. Even though the proportion of non-vector aphids associated with a plant far exceeds that of vector species, little is known about the effect of virus-infected plants on non-vector aphids. In the present study, the English grain aphid Sitobion avenae (Fabricius) (Hemiptera: Aphididae), a non-vector of Wheat dwarf virus (WDV) and Cereal yellow dwarf virus-RPV (CYDV-RPV), was monitored on, virus-infected, virus-free and leafhopper/aphid-infested, and virus- and insect-free (control) barley, Hordeum vulgare L. (Poales: Poaceae), plants. Electrical penetration graph recordings were performed. Compared with the control plants, S. avenae on infected plants exhibited reduced non-probing and pathway phase, and increased phloem sap ingestion phase, and more aphids reached sustained phloem ingestion. However, the electrical penetration graph parameters described above showed no significant differences in aphid feeding behavior on virus-free and vector pre-infested plants and the control barley plants during S. avenae feeding. The results suggest that WDV/CYDV-RPV-infected host plants positively affected the feeding behavior of the non-vector aphid S. avenae. Based on these results, the reasons and trends among the virus-infected host plants' effects on the feeding behavior of non-vector aphids are discussed. PMID:23902296

  10. THE ROLE OF BACTERIAL SYMBIONTS IN AMINO ACID COMPOSITION OF BLACK BEAN APHIDS

    Institute of Scientific and Technical Information of China (English)

    MingGan; De-ChengDing; Xue-xiaMiao

    2003-01-01

    To evaluate the role of bacterial symbionts ( Buchnera spp. ) in the black bean aphids ( Aphis craccivora Koch), the aphids were treated with the antibiotic, rifampicin, to eliminate their intracellular symbiotic bacteria. Analysis of protein and amino acid concentration in 7-day-old of aposymbiotic aphids showed that the total protein content per mg fresh weight was significantly reduced by 29 %, but free amino acid titers were increased by 17% . The ratio of the essential amino acids was in general only around 20% essential amino acids in phloem sap of broad bean, whereas it was 44% and 37% in symbiotic and aposymbiotic aphids, respectively,suggesting that the composition of the free amino acids was unbalanced. For example, the essential amino acid,threonine represented 21. 6% of essential amino acids in symbiotic aphids, but it was only 16.7% in aposymbiotic aphids. Likewise, two nonessential amino acids, tyrosine and serine, represented 8.9% and 5.6% of total amino acids in symbiontic aphids, respectively, but they enhanced to 21.1% and 13.6% in aposymbiotic aphids. It seems likely that the elevated free amino acid concentration in aposymbiotic aphids was caused by the limited protein anabolism as the result of the unbalanced amino acid composition.

  11. Identification and Analysis of Genetic Diversity Structure Within Pisum Genus Based on Microsatellite Markers

    Institute of Scientific and Technical Information of China (English)

    ZONG Xu-xiao; Rebecca Ford; Robert R Redden; GUAN Jian-ping; WANG Shu-min

    2009-01-01

    To assesse the genetic diversity among wild and cultivated accessions of 8 taxonomic groups in 2 species, and 5 subspecies under Pisum genus, and to analyze population structure and their genetic relationships among various groups of taxonomy,the study tried to verify the fitness of traditionally botanical taxonomic system under Pisum genus and to provide essential information for the exploration and utilization of wild relatives of pea genetic resources. 197 Pisum accessions from 62 counties of 5 continents were employed for SSR analysis using 21 polymorphic primer pairs in this study. Except for cultivated field pea Pisum sativum ssp. sativum vat. sativum (94 genotypes), also included were wild relative genotypes that were classified as belonging to P. fulvum, P. sativum ssp.abyssinicum, P. sativum ssp. asiaticum, P. sativum ssp. transcaucasicum, P. sativum ssp. elatius vat. elatius, P. sativum ssp. elatius vat. pumilio and P. sativum ssp.sativum vat. arvense (103 genotypes). The PCA analyses and 3-dimension PCA graphs were conducted and drawn by NTSYSpe 2.2d statistical package. Nei78 genetic distances among groups of genetic resources were calculated, and cluster analysis using UPGMA method was carried out by using Popgene V1.32 statistical package, the dendrogram was drawn by MEGA3.1 statistical package. Allelie statistics were carried out by Popgene V1.32. The significance test between groups of genotypes was carried out by Fstat V2.9.3.2 statistical package. 104 polymorphic bands were amplified using 21 SSR primer pairs with unambiguous unique polymorphic bands. 4.95 alleles were detected by each SSR primer pair in average, of which 65.56% were effective alleles for diversity. PSAD270, PSAC58, PSAA18, PSAC75, PSAA175 and PSAB72 were the most effective SSR pairs. SSR alleles were uniformly distributed among botanical taxon units under Pisum genus, but significant difference appeared in most pairwise comparisons for genetic diversity between taxon unit based

  12. The genetic diversity and evolution of field pea (Pisum studied by high throughput retrotransposon based insertion polymorphism (RBIP marker analysis

    Directory of Open Access Journals (Sweden)

    Smýkal Petr

    2010-02-01

    Full Text Available Abstract Background The genetic diversity of crop species is the result of natural selection on the wild progenitor and human intervention by ancient and modern farmers and breeders. The genomes of modern cultivars, old cultivated landraces, ecotypes and wild relatives reflect the effects of these forces and provide insights into germplasm structural diversity, the geographical dimension to species diversity and the process of domestication of wild organisms. This issue is also of great practical importance for crop improvement because wild germplasm represents a rich potential source of useful under-exploited alleles or allele combinations. The aim of the present study was to analyse a major Pisum germplasm collection to gain a broad understanding of the diversity and evolution of Pisum and provide a new rational framework for designing germplasm core collections of the genus. Results 3020 Pisum germplasm samples from the John Innes Pisum germplasm collection were genotyped for 45 retrotransposon based insertion polymorphism (RBIP markers by the Tagged Array Marker (TAM method. The data set was stored in a purpose-built Germinate relational database and analysed by both principal coordinate analysis and a nested application of the Structure program which yielded substantially similar but complementary views of the diversity of the genus Pisum. Structure revealed three Groups (1-3 corresponding approximately to landrace, cultivar and wild Pisum respectively, which were resolved by nested Structure analysis into 14 Sub-Groups, many of which correlate with taxonomic sub-divisions of Pisum, domestication related phenotypic traits and/or restricted geographical locations. Genetic distances calculated between these Sub-Groups are broadly supported by principal coordinate analysis and these, together with the trait and geographical data, were used to infer a detailed model for the domestication of Pisum. Conclusions These data provide a clear picture

  13. Host Plant Specialization in the Sugarcane Aphid Melanaphis sacchari.

    Directory of Open Access Journals (Sweden)

    Samuel Nibouche

    Full Text Available Most aphids are highly specialized on one or two related plant species and generalist species often include sympatric populations adapted to different host plants. Our aim was to test the hypothesis of the existence of host specialized lineages of the aphid Melanaphis sacchari in Reunion Island. To this end, we investigated the genetic diversity of the aphid and its association with host plants by analyzing the effect of wild sorghum Sorghum bicolor subsp. verticilliflorum or sugarcane as host plants on the genetic structuring of populations and by performing laboratory host transfer experiments to detect trade-offs in host use. Genotyping of 31 samples with 10 microsatellite loci enabled identification of 13 multilocus genotypes (MLG. Three of these, Ms11, Ms16 and Ms15, were the most frequent ones. The genetic structure of the populations was linked to the host plants. Ms11 and Ms16 were significantly more frequently observed on sugarcane, while Ms15 was almost exclusively collected in colonies on wild sorghum. Laboratory transfer experiments demonstrated the existence of fitness trade-offs. An Ms11 isofemale lineage performed better on sugarcane than on sorghum, whereas an Ms15 lineage developed very poorly on sugarcane, and two Ms16 lineages showed no significant difference in performances between both hosts. Both field and laboratory results support the existence of host plant specialization in M. sacchari in Reunion Island, despite low genetic differentiation. This study illustrates the ability of asexual aphid lineages to rapidly undergo adaptive changes including shifting from one host plant to another.

  14. Theoretical and experimental studies on behavioral syndromes in aphids

    OpenAIRE

    Simon, Franz Wesley

    2014-01-01

    Individuals’ behaviors can be correlated across time and contexts, in a phenomenon now known as behavioral syndromes. Using an experimental approach, I demonstrate that genetically identical pea aphids are highly repeatable in multiple behavioral traits, however these behaviors are uncorrelated. Then using a state variable model I show that asymmetries in size can maintain a hierarchy between least and most bold individuals in foraging intensity across development. However, individuals tha...

  15. Orange oil effect in the control of fennel aphid

    Directory of Open Access Journals (Sweden)

    Ivanildo Cavalcanti de Albuquerque

    2009-08-01

    Full Text Available In the properties where fennel is grown, in the states of Bahia, Sergipe, Pernambuco and Paraiba, at the Northeast of Brazil, a high rate of usage of pesticides in the crop, aiming to control the aphid Hyadaphis foeniculi. The purpose of this study was to evaluate the effect of orange oil Prev-Am (sodium tetraborohydrate decahydrate, in the control of H. foeniculi aphid of the fennel crop. The trial was conducted in a fennel field located in Lagoa Seca Experimental Station, belonging to the EMEPA-PB. Forty-eight hours after the product has been sprayed, one flower of the umbel was collected and removed her aphids, which were placed in a "petri" plate from 9cm in diameter. As a following step, the insects were counted as part of two groups, considering the number of insects dead and alive, being tabulated for later analysis. The data were subjected to analysis of variance, using the experimental design of randomized blocks composed of six treatments (doses of 0.3, 0.4, 0.5, 0.6, 0.7% of orange oil (Prev-am and pure water as check, with five repetitions. The data were submitted to the regression analysis. The orange oil (Prev-am controls effectively H. foeniculi at the concentration of 0.3%, increasing the control up to concentrations of 0.6 and 0.7%. The product does not kill ladybugs (Cycloneda sanguinea and can be used in programs for integrated pest management.Keywords: Foeniculum vulgare, aphid, vegetable oil, ladybug, umbel.

  16. The Process of Aphid Egg-Laying and the Little Known Role of the Coccinellidae in Aphid Egg Destruction in Poland – Preliminary Results

    Directory of Open Access Journals (Sweden)

    Lubiarz Magdalena

    2014-07-01

    Full Text Available No detailed studies have been conducted in Poland with regard to aphid eggs or egg survival in particular. So far, no studies have been conducted concerning the role of ladybird beetles in reducing the number of aphid eggs in spring, before the development of leaves, and in autumn, after the leaves have been shed. At these times, other developmental stages of aphids are unavailable as food for the ladybirds. The paper presents the preliminary results of a three-year study on the process of aphid egg-laying (especially Chaetosiphon tetrarhodum, Macrosiphum rosae, Metopolophium dirhodum, and Maculolachnus submacula. The paper also deals with the little known role of ladybirds in aphid egg destruction. Research was conducted in Otrębusy (Western Mazovia, Poland, in the years 2008-2010, on the rugosa rose and on the dog rose. In the years 2011-2013, in Otrębusy, the occurrence of M. submacula was also observed on the ornamental grandiflora rose. Furthermore, in the years 2003-2004, observations were conducted on the pedunculate oak in Polesie National Park and in the town of Puławy (Lublin Region, Poland. The observations which took place in Puławy focused on egglaying of aphids representing the genera Phylloxera and Lachnus. The study investigated aphid oviposition sites. Data was collected on the number of aphid eggs noted on the studied plants. The study also showed, that sometimes winter eggs of aphids could provide nutrition for ladybirds. This was especially true in autumn when ladybird beetles were preparing for hibernation.

  17. The Potato Aphid Salivary Effector Me47 Is a Glutathione-S-Transferase Involved in Modifying Plant Responses to Aphid Infestation.

    Science.gov (United States)

    Kettles, Graeme J; Kaloshian, Isgouhi

    2016-01-01

    Polyphagous aphid pests cause considerable economic damage to crop plants, primarily through the depletion of photoassimilates and transfer of viruses. The potato aphid (Macrosiphum euphorbiae) is a notable pest of solanaceous crops, however, the molecular mechanisms that underpin the ability to colonize these hosts are unknown. It has recently been demonstrated that like other aphid species, M. euphorbiae injects a battery of salivary proteins into host plants during feeding. It is speculated that these proteins function in a manner analagous to secreted effectors from phytopathogenic bacteria, fungi and oomycetes. Here, we describe a novel aphid effector (Me47) which was identified from the potato aphid salivary secretome as a putative glutathione-S-transferase (GST). Expression of Me47 in Nicotiana benthamiana enhanced reproductive performance of green peach aphid (Myzus persicae). Similarly, delivery of Me47 into leaves of tomato (Solanum lycopersicum) by Pseudomonas spp. enhanced potato aphid fecundity. In contrast, delivery of Me47 into Arabidopsis thaliana reduced GPA reproductive performance, indicating that Me47 impacts the outcome of plant-aphid interactions differently depending on the host species. Delivery of Me47 by the non-pathogenic Pseudomonas fluorescens revealed that Me47 protein or activity triggers defense gene transcriptional upregulation in tomato but not Arabidopsis. Recombinant Me47 was purified and demonstrated to have GST activity against two specific isothiocyanates (ITCs), compounds implicated in herbivore defense. Whilst GSTs have previously been associated with development of aphid resistance to synthetic insecticides, the findings described here highlight a novel function as both an elicitor and suppressor of plant defense when delivered into host tissues. PMID:27536306

  18. The Potato Aphid Salivary Effector Me47 Is a Glutathione-S-Transferase Involved in Modifying Plant Responses to Aphid Infestation

    Science.gov (United States)

    Kettles, Graeme J.; Kaloshian, Isgouhi

    2016-01-01

    Polyphagous aphid pests cause considerable economic damage to crop plants, primarily through the depletion of photoassimilates and transfer of viruses. The potato aphid (Macrosiphum euphorbiae) is a notable pest of solanaceous crops, however, the molecular mechanisms that underpin the ability to colonize these hosts are unknown. It has recently been demonstrated that like other aphid species, M. euphorbiae injects a battery of salivary proteins into host plants during feeding. It is speculated that these proteins function in a manner analagous to secreted effectors from phytopathogenic bacteria, fungi and oomycetes. Here, we describe a novel aphid effector (Me47) which was identified from the potato aphid salivary secretome as a putative glutathione-S-transferase (GST). Expression of Me47 in Nicotiana benthamiana enhanced reproductive performance of green peach aphid (Myzus persicae). Similarly, delivery of Me47 into leaves of tomato (Solanum lycopersicum) by Pseudomonas spp. enhanced potato aphid fecundity. In contrast, delivery of Me47 into Arabidopsis thaliana reduced GPA reproductive performance, indicating that Me47 impacts the outcome of plant–aphid interactions differently depending on the host species. Delivery of Me47 by the non-pathogenic Pseudomonas fluorescens revealed that Me47 protein or activity triggers defense gene transcriptional upregulation in tomato but not Arabidopsis. Recombinant Me47 was purified and demonstrated to have GST activity against two specific isothiocyanates (ITCs), compounds implicated in herbivore defense. Whilst GSTs have previously been associated with development of aphid resistance to synthetic insecticides, the findings described here highlight a novel function as both an elicitor and suppressor of plant defense when delivered into host tissues.

  19. INFLUENCE OF NOSTOC VAUCHER EX BORNET ET FLAHAULT STRAINS ON GROWTH AND DEVELOPMENT OF PISUM SATIVUM L.

    Directory of Open Access Journals (Sweden)

    Maltsev Ye. I.

    2015-12-01

    Full Text Available We investigated the positive impact of cultures cyanobacteria genus Nostoc Vaucher ex Bornet et Flahault on growth and development of higher plants as an example Pisum sativum L. All the Nostoc species have a positive effect on the viability, germination energy, and biometric characteristics of Pisum sativum. The greatest positive influence was registered for N. entophytum Born. et. Flah. and N. linckia (Roth Bornetet Flahault f. linckia.

  20. 77 FR 46373 - Field Release of Aphelinus glycinis for the Biological Control of the Soybean Aphid in the...

    Science.gov (United States)

    2012-08-03

    ... the Biological Control of the Soybean Aphid in the Continental United States; Availability of an... release of Aphelinus glycinis for the biological control of the soybean aphid, Aphis glycines, in the...-2323. SUPPLEMENTARY INFORMATION: Background The soybean aphid, Aphis glycinis, which is native to...

  1. Impact of aphid alarm pheromone release on virus transmission efficiency: When pest control strategy could induce higher virus dispersion.

    Science.gov (United States)

    Lin, Fang-Jing; Bosquée, Emilie; Liu, Ying-Jie; Chen, Ju-Lian; Yong, Liu; Francis, Frédéric

    2016-09-01

    Aphids cause serious damages to crops not only by tacking sap but also by transmitting numerous viruses. To develop biological control, the aphid alarm pheromone, namely E-β-farnesene (EβF), has been demonstrated to be efficient to repel aphids and as attract beneficials, making it a potential tool to control aphid pests. Considering aphids also as virus vectors, changes of their behavior could also interfere with the virus acquisition and transmission process. Here, a combination of two aphid species and two potato virus models were selected to test the influence of EβF release on aphid and virus dispersion under laboratory conditions. EβF release was found to significantly decrease the population of Myzus persicae and Macrosiphum euphorbiae around the infochemical releaser but simultaneously also increasing the dispersal of Potato Virus Y (PVY). At the opposite, no significant difference for Potato Leaf Roll Virus (PLRV) transmission efficiency was observed with similar aphid alarm pheromone releases for none of the aphid species. These results provide some support to carefully consider infochemical releasers not only for push-pull strategy and pest control but also to include viral disease in a the plant protection to aphids as they are also efficient virus vectors. Impact of aphid kinds and transmission mechanisms will be discussed according to the large variation found between persistent and non persistent potato viruses and interactions with aphids and related infochemicals.

  2. The Process of Aphid Egg-Laying and the Little Known Role of the Coccinellidae in Aphid Egg Destruction in Poland – Preliminary Results

    OpenAIRE

    Lubiarz Magdalena; Cichocka Elżbieta

    2014-01-01

    No detailed studies have been conducted in Poland with regard to aphid eggs or egg survival in particular. So far, no studies have been conducted concerning the role of ladybird beetles in reducing the number of aphid eggs in spring, before the development of leaves, and in autumn, after the leaves have been shed. At these times, other developmental stages of aphids are unavailable as food for the ladybirds. The paper presents the preliminary results of a three-year study on the process of ap...

  3. MOLECULAR CLONING, EXPRESSION PATTERN OF MULTIDRUG RESISTANCE ASSOCIATED PROTEIN 1 (MRP1, ABCC1) GENE, AND THE SYNERGISTIC EFFECTS OF VERAPAMIL ON TOXICITY OF TWO INSECTICIDES IN THE BIRD CHERRY-OAT APHID.

    Science.gov (United States)

    Kang, Xin-Le; Zhang, Meng; Wang, Kang; Qiao, Xian-Feng; Chen, Mao-Hua

    2016-05-01

    The ATP-binding cassette (ABC) transporters are important transmembrane proteins encoded by a supergene family. The majority of ABC proteins are primary active transporters that bind and hydrolyze ATP to mediate the efflux of a diverse range of substrates across lipid membranes. In this study, we cloned and characterized a putative multidrug resistance associated protein 1 (MRP1) from Rhopalosiphum padi encoded by ABCC1. Structural analysis showed that this protein has structural features typical of the ABC transporter family. Phylogenetic analysis indicated that the amino acid sequence was highly similar that of the corresponding protein from Acyrthosiphon pisum. Real-time quantitative polymerase chain reaction (PCR) analysis showed that ABCC1 was expressed throughout all R. padi developmental stages, with the highest level of expression in the fourth larval instar. We also examined ABCC1 expression in four different tissue types and found that it was most highly expressed in the midgut. Exposing R. padi to imidacloprid and chlorpyrifos increased ABCC1 expression. Furthermore, ABCC1 expression was higher in the imidacloprid-resistant (IR) and chlorpyrifos-resistant (CR) strains than in an insecticide-susceptible strain (SS) of R. padi. Exposing R. padi to verapamil in combination with insecticides significantly increased the toxicity of the insecticides. The respective synergy factor of CR and IR R. padi strain was 1.33 and 1.26, which was lower than that (2.72 and 1.64, respectively) of the SS. Our results clarify the biological function of ABCC1 in R. padi, particularly its role in insecticide resistance, and suggest novel strategies for pest management that use ABC transporter inhibitors to increase the effectiveness of insecticides. PMID:27110952

  4. The molecular basis of the interactions between luteoviruses and their aphid vectors

    NARCIS (Netherlands)

    Hogenhout, S.A.

    1999-01-01

    Luteoviruses essentially replicate in the phloem tissue and are transmitted from plant to plant by aphids in a circulative, persistent manner. Virus particles are acquired when aphids feed on phloem sap. Particles are then transported from the midgut or hindgut into the haemolymph and from the haemo

  5. The Effects of Aphid Traits on Parasitoid Host Use and Specialist Advantage

    Science.gov (United States)

    Gagic, Vesna; Petrović-Obradović, Olivera; Fründ, Jochen; Kavallieratos, Nickolas G.; Athanassiou, Christos G.; Starý, Petr; Tomanović, Željko

    2016-01-01

    Specialization is a central concept in ecology and one of the fundamental properties of parasitoids. Highly specialized parasitoids tend to be more efficient in host-use compared to generalized parasitoids, presumably owing to the trade-off between host range and host-use efficiency. However, it remains unknown how parasitoid host specificity and host-use depends on host traits related to susceptibility to parasitoid attack. To address this question, we used data from a 13-year survey of interactions among 142 aphid and 75 parasitoid species in nine European countries. We found that only aphid traits related to local resource characteristics seem to influence the trade-off between host-range and efficiency: more specialized parasitoids had an apparent advantage (higher abundance on shared hosts) on aphids with sparse colonies, ant-attendance and without concealment, and this was more evident when host relatedness was included in calculation of parasitoid specificity. More traits influenced average assemblage specialization, which was highest in aphids that are monophagous, monoecious, large, highly mobile (easily drop from a plant), without myrmecophily, habitat specialists, inhabit non-agricultural habitats and have sparse colonies. Differences in aphid wax production did not influence parasitoid host specificity and host-use. Our study is the first step in identifying host traits important for aphid parasitoid host specificity and host-use and improves our understanding of bottom-up effects of aphid traits on aphid-parasitoid food web structure. PMID:27309729

  6. Soybean Aphid Infestation Induces Changes in Fatty Acid Metabolism in Soybean.

    Directory of Open Access Journals (Sweden)

    Charles Kanobe

    Full Text Available The soybean aphid (Aphis glycines Matsumura is one of the most important insect pests of soybeans in the North-central region of the US. It has been hypothesized that aphids avoid effective defenses by inhibition of jasmonate-regulated plant responses. Given the role fatty acids play in jasmonate-induced plant defenses, we analyzed the fatty acid profile of soybean leaves and seeds from aphid-infested plants. Aphid infestation reduced levels of polyunsaturated fatty acids in leaves with a concomitant increase in palmitic acid. In seeds, a reduction in polyunsaturated fatty acids was associated with an increase in stearic acid and oleic acid. Soybean plants challenged with the brown stem rot fungus or with soybean cyst nematodes did not present changes in fatty acid levels in leaves or seeds, indicating that the changes induced by aphids are not a general response to pests. One of the polyunsaturated fatty acids, linolenic acid, is the precursor of jasmonate; thus, these changes in fatty acid metabolism may be examples of "metabolic hijacking" by the aphid to avoid the induction of effective defenses. Based on the changes in fatty acid levels observed in seeds and leaves, we hypothesize that aphids potentially induce interference in the fatty acid desaturation pathway, likely reducing FAD2 and FAD6 activity that leads to a reduction in polyunsaturated fatty acids. Our data support the idea that aphids block jasmonate-dependent defenses by reduction of the hormone precursor.

  7. GroEL from the endosymbiont Buchnera aphidicola betrays the aphid by triggering plant defense.

    Science.gov (United States)

    Chaudhary, Ritu; Atamian, Hagop S; Shen, Zhouxin; Briggs, Steven P; Kaloshian, Isgouhi

    2014-06-17

    Aphids are sap-feeding plant pests and harbor the endosymbiont Buchnera aphidicola, which is essential for their fecundity and survival. During plant penetration and feeding, aphids secrete saliva that contains proteins predicted to alter plant defenses and metabolism. Plants recognize microbe-associated molecular patterns and induce pattern-triggered immunity (PTI). No aphid-associated molecular pattern has yet been identified. By mass spectrometry, we identified in saliva from potato aphids (Macrosiphum euphorbiae) 105 proteins, some of which originated from Buchnera, including the chaperonin GroEL. Because GroEL is a widely conserved bacterial protein with an essential function, we tested its role in PTI. Applying or infiltrating GroEL onto Arabidopsis (Arabidopsis thaliana) leaves induced oxidative burst and expression of PTI early marker genes. These GroEL-induced defense responses required the known coreceptor BRASSINOSTEROID INSENSITIVE 1-ASSOCIATED RECEPTOR KINASE 1. In addition, in transgenic Arabidopsis plants, inducible expression of groEL activated PTI marker gene expression. Moreover, Arabidopsis plants expressing groEL displayed reduced fecundity of the green peach aphid (Myzus persicae), indicating enhanced resistance against aphids. Furthermore, delivery of GroEL into tomato (Solanum lycopersicum) or Arabidopsis through Pseudomonas fluorescens, engineered to express the type III secretion system, also reduced potato aphid and green peach aphid fecundity, respectively. Collectively our data indicate that GroEL is a molecular pattern that triggers PTI. PMID:24927572

  8. Aphidoletes aphidimyza oviposition behaviour when multiple aphid pests are present in the greenhouse

    Science.gov (United States)

    The generalist aphid predator Aphidoletes aphidimyza was investigated for oviposition behaviour on the pest aphids Myzus persicae and Aulacorthum solani in greenhouse trials. Oviposition was significantly lower on A. solani than M. persicae. Myzus persicae were concentrated at the growing points of ...

  9. National Plant Diagnostic Network, Taxonomic training videos: Aphids under the microscope - Aphis gossypii

    Science.gov (United States)

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides provides training to identify the cotton aphid, Aphis gossypii, using a compound microscope and an electronic identification key called “LUCID.” The video demonstrates key morphological structures that ca...

  10. National Plant Diagnostic Network, Taxonomic training videos: Aphids under the microscope - Myzus persicae

    Science.gov (United States)

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides provides training to identify the green peach aphid, Myzus persicae, using a compound microscope and an electronic identification key called “LUCID.” The video demonstrates key morphological structures t...

  11. National Plant Diagnostic Network, Taxonomic training videos: Aphids under the microscope - Cerataphis brasiliensis

    Science.gov (United States)

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides provides training to identify the palm aphid, Cerataphis brasiliensis, using a compound microscope and an electronic identification key called “LUCID.” The video demonstrates key morphological structures...

  12. Detection and decay rates of prey and prey symbionts in the gut of a predator through metagenomics.

    Science.gov (United States)

    Paula, Débora P; Linard, Benjamin; Andow, David A; Sujii, Edison R; Pires, Carmen S S; Vogler, Alfried P

    2015-07-01

    DNA methods are useful to identify ingested prey items from the gut of predators, but reliable detection is hampered by low amounts of degraded DNA. PCR-based methods can retrieve minute amounts of starting material but suffer from amplification biases and cross-reactions with the predator and related species genomes. Here, we use PCR-free direct shotgun sequencing of total DNA isolated from the gut of the harlequin ladybird Harmonia axyridis at five time points after feeding on a single pea aphid Acyrthosiphon pisum. Sequence reads were matched to three reference databases: Insecta mitogenomes of 587 species, including H. axyridis sequenced here; A. pisum nuclear genome scaffolds; and scaffolds and complete genomes of 13 potential bacterial symbionts. Immediately after feeding, multicopy mtDNA of A. pisum was detected in tens of reads, while hundreds of matches to nuclear scaffolds were detected. Aphid nuclear DNA and mtDNA decayed at similar rates (0.281 and 0.11 h(-1) respectively), and the detectability periods were 32.7 and 23.1 h. Metagenomic sequencing also revealed thousands of reads of the obligate Buchnera aphidicola and facultative Regiella insecticola aphid symbionts, which showed exponential decay rates significantly faster than aphid DNA (0.694 and 0.80 h(-1) , respectively). However, the facultative aphid symbionts Hamiltonella defensa, Arsenophonus spp. and Serratia symbiotica showed an unexpected temporary increase in population size by 1-2 orders of magnitude in the predator guts before declining. Metagenomics is a powerful tool that can reveal complex relationships and the dynamics of interactions among predators, prey and their symbionts.

  13. Impact of dyeing industry effluent on germination and growth of pea (Pisum sativum).

    Science.gov (United States)

    Malaviya, Piyush; Hali, Rajesh; Sharma, Neeru

    2012-11-01

    Dye industry effluent was analyzed for physico-chemical characteristics and its impact on germination and growth behaviour of Pea (Pisum sativum). The 100% effluent showed high pH (10.3) and TDS (1088 mg l(-1)). The germination parameters included percent germination, delay index, speed of germination, peak value and germination period while growth parameters comprised of root and shoot length, root and shootweight, root-shoot ratio and number of stipules. The study showed the maximum values of positive germination parameters viz. speed of germination (7.85), peak value (3.28), germination index (123.87) and all growth parameters at 20% effluent concentration while the values of negative germination parameters viz. delay index (-0.14) and percent inhibition (-8.34) were found to be minimum at 20% effluent concentration. The study demonstrated that at lower concentrations the dyeing industry effluent caused a positive impact on germination and growth of Pisum sativum. PMID:23741804

  14. Linkages in Pisum L. Pt. 7. Locus for the sterile gene calf (cabbage leaf)

    International Nuclear Information System (INIS)

    The recessive, pleiotropic gene calf, artificially induced was described by Sharma in 1975. An identical mutant gene at the same locus was isolated in this research. Two lines were included in the Pisum gene bank - the type line for the gene calf - Wt 15873 and the representative line - Wt 16024. In linkage studies the representative line was crossed with tester lines bearing gene markers. Analyses of dihybrid segregation in F2 generations revealed linkages of the gene calf with chromosome 2 markers. Two isozymic markers helped to reveal the calf locus on chromosome 2 with the following order: Orp - Calf - K Pgm-p Fum. This is agriment with the current Pisum linkage map

  15. Parasitoids and hyperparasitoids (Hymenoptera) on aphids (Hemiptera) infesting citrus in east Mediterranean region of Turkey.

    Science.gov (United States)

    Satar, Serdar; Satar, Gül; Karacaoğlu, Mehmet; Uygun, Nedim; Kavallieratos, Nickolas G; Starý, Petr; Athanassiou, Christos G

    2014-01-01

    The aphids, aphid parasitoids, and hyperparasitoids found in citrus orchards, the parasitoids' and hyperparasitoids' seasonal abundance, and the plant-aphid-parasitoid relationships in Hatay, Osmaniye, Adana, and Mersin provinces of the east Mediterranean region of Turkey are presented in the present 2-yr study. Aphidius colemani Viereck, Binodoxys angelicae (Haliday), and Lysiphlebus confusus Tremblay and Eady (Hymenoptera: Braconidae: Aphidiinae) were encountered as the most common parasitoids among 10 identified aphidiine and aphelinid taxa on different citrus species. Hyperparasitoids belonging to the genera Alloxysta, Phaenoglyphis, Asaphes, Pachyneuron, Syrphophagus, and Dendrocerus are reported for the first time emerging from aphids feeding on citrus in Turkey. Among them, Asaphes spp., Pachyneuron spp., and Syrphophagus spp. were recorded as the most common ones. Citrus reticulata Blanco and Citrus limon (L.) Burm. fil. were recorded as main hosts for the aphid parasitoids and their hyperparasitoids. PMID:25480969

  16. Relationships Between Aphids (Insecta: Homoptera: Aphididae) and Slugs (Gastropoda: Stylommatophora: Agriolimacidae) Pests of Legumes (Fabaceae: Lupinus).

    Science.gov (United States)

    Kozłowski, Jan; Strażyński, Przemysław; Jaskulska, Monika; Kozłowska, Maria

    2016-01-01

    Lupin plants are frequently damaged by various herbivorous invertebrates. Significant among these are slugs and aphids, which sometimes attack the same plants. Relationships between aphids, slugs and food plant are very interesting. Grazing by these pests on young plants can lead to significant yield losses. There is evidence that the alkaloids present in some lupin plants may reduce grazing by slugs, aphids and other invertebrates. In laboratory study was analyzed the relationships between aphid Aphis craccivora and slug Deroceras reticulatum pests of legumes Lupinus angustifolius. It was found that the presence of aphids significantly reduced slug grazing on the plants. The lupin cultivars with high alkaloid content were found to be less heavily damaged by D. reticulatum, and the development of A. craccivora was found to be inhibited on such plants. PMID:27324580

  17. Reliable screening technique for evaluation of wild crucifers against mustard aphid Lipaphis erysimi (Kalt.).

    Science.gov (United States)

    Singh, S P; Kumar, Sandeep; Singh, Y P; Singh, Ram

    2014-12-01

    Wild crucifers namely Arabidopsis thaliana, Brassica fruticulosa, B. rugosa, B. spinescens, B. tournefortii, Camelina sativa, Capsella bursa-pastoris, Crambe abysinnica, Cronopus didymus, Diplotaxis assurgens, D. gomez-campoi, D. muralis, D. siettiana, D. tenuisiliqua, Enatharocarpus lyratus, Lepidium sativum and Sinapis alba along with five cultivated Brassica species including B. rapa (BSH-1), B. juncea (Rohini), B. napus (GSC-6), B. carinata (DLSC-2) and Eruca sativa (T-27) were screened against mustard aphid Lipaphis erysimi (Kalt.) with a standardized technique under definite level of aphid pressure developed using specially designed cages. Observations have revealed that B. fruticulosa, B. spinescens, Camelina sativa, Crambe abysinnica and Lepidium sativum were resistant to mustard aphid L. erysimi with aphid infestation index (AII) ≤ 1. Capsella bursa-pastoris was highly susceptible to bean aphid, Aphis fabae during its vegetative stage (with 100% mortality). Other genotypes were found in the range of 'susceptible' to 'highly susceptible' with AII ranging 3-5.

  18. Comportement agronomique d'une collection de pois (Pisum sativum L)

    OpenAIRE

    M. BOUSLAMA; Rezgui, S.; Hannachi, C.; Mani, F.

    2007-01-01

    Agronomical Behaviour of a Pea Collection (Pisum sativum L.). This experience was achieved under greenhouse conditions. Twelve genotypes of pea were used (Asgrow, Jumbo, Lincoln, Merveille de Kelvedon, Purser, Rajai Torpe, Snajor Kosep, Korai,Wando, Rondo, local genotype, Major Kosep Korai and Surgevil). They were cultivated on peat during 5.5 months (from October to April). Some agronomical parameters were studied: resistance to diseases, (Powdery-mildew, mildew, top yellow virus, anthracnos...

  19. Nitrogen and phosphorus compounds in the aleurone grains of Iris pseudoacorus endosperm and Pisum sativum cotyledons

    OpenAIRE

    Ligia Konopska

    2015-01-01

    Aleurone grains from Iris pseudoacorus endosperm and Pisum sativum cotyledons were isolated partly according to Tombs's method (1967). Nitrogen compounds content was determined in them by Kjeldahl's micromethod, and in the particular fractions after Thiman and Laloraya (1960). Mainly protein N was detected in the aleurone grains, constituting 14.8 and 15.2 per cent of the dry mass of pea and Iris seeds, respectively. Moreover, phosphorus compounds were fractionated according to Holden and Pir...

  20. Sources of reducing equivalents for nitrite reductase in Pisum arvense roots

    OpenAIRE

    Grażyna Kłobus

    2014-01-01

    Glucose-6-phosphate and NADP+ as well as malic acid and NADP+ present in the incubation mixture enhanced nitrite reductase (EC 1.6.6.4) activity in Pisum arvense roots. This was manifested by a depression of the nitrite level in the tissues and an increased reduction of nitrites by plastids isolated from P. arvense roots. A marked stimulation of plastid malate dehydrogenase was also observed under the influence of nitrates present in the medium. These results suggest that pyridin nucleotides ...

  1. NCBI nr-aa BLAST: CBRC-TTRU-01-1236 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TTRU-01-1236 ref|YP_002468587.1| hypothetical protein BUAPTUC7_278 [Buchnera a...phidicola str. Tuc7 (Acyrthosiphon pisum)] gb|ACL30092.1| hypothetical protein BUAPTUC7_278 [Buchnera aphidicola str. Tuc7 (Acyrthosiphon pisum)] YP_002468587.1 0.005 26% ...

  2. NCBI nr-aa BLAST: CBRC-TTRU-01-1236 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TTRU-01-1236 ref|YP_002468032.1| hypothetical protein BUAP5A_276 [Buchnera aph...ola str. LSR1 (Acyrthosiphon pisum)] gb|ACL30644.1| hypothetical protein BUAP5A_276 [Buchnera aphidicola str. 5A (Acyrthosiphon pisum)] YP_002468032.1 0.005 26% ...

  3. NCBI nr-aa BLAST: CBRC-VPAC-01-0194 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available yltransferase [Candidatus Hamiltonella defensa 5AT (Acyrthosiphon pisum)] gb|ACQ67332.1| UDP-3-O-(3-hydroxym...yristoyl)-glucosamine N-acyltransferase [Candidatus Hamiltonella defensa 5AT (Acyrthosiphon pisum)] YP_002923480.1 0.58 29% ...

  4. NCBI nr-aa BLAST: CBRC-MDOM-11-0019 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available (LIV-II) (LIVCS family) [Candidatus Hamiltonella defensa 5AT (Acyrthosiphon pisum)] gb|ACQ67379.1| branched...-chain amino acid transport system II (LIV-II) (LIVCS family) [Candidatus Hamiltonella defensa 5AT (Acyrthosiphon pisum)] YP_002923527.1 4.1 29% ...

  5. NCBI nr-aa BLAST: CBRC-VPAC-01-0381 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available yltransferase [Candidatus Hamiltonella defensa 5AT (Acyrthosiphon pisum)] gb|ACQ67332.1| UDP-3-O-(3-hydroxym...yristoyl)-glucosamine N-acyltransferase [Candidatus Hamiltonella defensa 5AT (Acyrthosiphon pisum)] YP_002923480.1 0.76 28% ...

  6. NCBI nr-aa BLAST: CBRC-TTRU-01-1371 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available ndent protein export [Candidatus Hamiltonella defensa 5AT (Acyrthosiphon pisum)] gb|ACQ68339.1| twin-arginin...e translocase subunit, sec-independent protein export [Candidatus Hamiltonella defensa 5AT (Acyrthosiphon pisum)] YP_002924487.1 0.89 24% ...

  7. Methyl salicylate attracts natural enemies and reduces populations of soybean aphids (Hemiptera: Aphididae) in soybean agroecosystems.

    Science.gov (United States)

    Mallinger, Rachel E; Hogg, David B; Gratton, Claudio

    2011-02-01

    Methyl salicylate, an herbivore-induced plant volatile, has been shown to attract natural enemies and affect herbivore behavior. In this study, methyl salicylate was examined for its attractiveness to natural enemies of the soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), and for its direct effects on soybean aphid population growth rates. Methyl salicylate lures were deployed in plots within organic soybean [Glycine max (L.) Merr.] fields. Sticky card traps adjacent to and 1.5 m from the lure measured the relative abundance of natural enemies, and soybean aphid populations were monitored within treated and untreated plots. In addition, exclusion cage studies were conducted to determine methyl salicylate's effect on soybean aphid population growth rates in the absence of natural enemies. Significantly greater numbers of syrphid flies (Diptera: Syrphidae) and green lacewings (Neuroptera: Chrysopidae) were caught on traps adjacent to the methyl salicylate lure, but no differences in abundance were found at traps 1.5 m from the lure. Furthermore, abundance of soybean aphids was significantly lower in methyl salicylate-treated plots. In exclusion cage studies, soybean aphid numbers were significantly reduced on treated soybean plants when all plants were open to natural enemies. When plants were caged, however, soybean aphid numbers and population growth rates did not differ between treated and untreated plants suggesting no effect of methyl salicylate on soybean aphid reproduction and implicating the role of natural enemies in depressing aphid populations. Although aphid populations were reduced locally around methyl salicylate lures, larger scale studies are needed to assess the technology at the whole-field scale.

  8. Parasitization of commercially available parasitoid species against the lettuce aphid, Nasonovia ribisnigri (Hemiptera: Aphididae).

    Science.gov (United States)

    Shrestha, G; Skovgård, H; Enkegaard, A

    2014-12-01

    The lettuce aphid, Nasonovia ribisnigri (Mosley), is an economically important pest of lettuce worldwide. Little documentation exists for the control efficacy of aphid parasitoids against N. ribisnigri. This laboratory study evaluated three commercially available parasitoid species: Aphidius colemani (Viereck), Lysiphlebus testaceipes (Cresson), and Aphelinus abdominalis (Dalman) for their mortality impact on N. ribisnigri. The green peach aphid Myzus persicae (Sulzer) was included as a reference aphid. The study showed that A. abdominalis successfully parasitized 39 and 13% of the offered N. ribisnigri and M. persicae, respectively, within a 24-h exposure period. In contrast, none of the lettuce aphids exposed to Ap. colemani or L. testaceipes were successfully parasitized, whereas 60 and 3.5% of M. persicae, respectively, were successfully parasitized within a 6-h exposure period. Lettuce aphid mortality due to incomplete parasitization was 26 and 31% when exposed to Ap. colemani and L. testaceipes, respectively, with corresponding values for M. persicae being 5 and 10%, respectively. Mortality as a result of incomplete parasitization when aphids were exposed to A. abdominalis was low for both aphid species. The total mortality inflicted by A. abdominalis within a 24-h exposure period was 51% for the lettuce aphids and significantly less (19%) for green peach aphids. In contrast, Ap. colemani inflicted a higher mortality in M. persicae (65%) compared with N. ribisnigri (26%) within a 6-h exposure period. L. testaceipes caused a greater mortality in N. ribisnigri as compared with M. persicae. This study concludes that A. abdominalis has the potential to be used against N. ribisnigri in inoculative biocontrol programs as compared with the other parasitoid species based on successful parasitization. PMID:25290653

  9. Weed Host Specificity of the Aphid, Aphis spiraecola: Developmental and Reproductive Performance of Aphids in Relation to Plant Growth and Leaf Chemicals of the Siam Weed, Chromolaena odorata

    OpenAIRE

    Agarwala, B. K.; Das, Jhuma

    2012-01-01

    Density, distribution, and nutritional quality of plants are the causal basis of host plant selection in aphids. Nutritional qualities of a plant vary according to its growth stage and also in response to seasonal variation. How host plant growth stages shape aphid performance was studied in Aphis spiraecola Patch (Homoptera: Aphididae) on the perennial Siam weed, Chromolaena odorata (L.) King and Robinson (Asterales: Asteraceae). This plant species is the preferred host in the hot and humid ...

  10. Survey of aphid population in a yellow passion fruit crop and its relationship on the spread Cowpea aphid-borne mosaic virus in a subtropical region of Brazil

    OpenAIRE

    Garcêz, Renata Maia; Chaves, Alexandre Levi Rodrigues; Eiras, Marcelo; Meletti, Laura Maria Molina; de Azevedo Filho, Joaquim Adelino; da Silva, Leonardo Assis; Colariccio, Addolorata

    2015-01-01

    Background Passion fruit woodiness may be caused by Cowpea aphid-borne mosaic virus (CABMV) and is currently the major passion fruit disease in Brazil. To assess the virus-vector-host interactions, a newly introduced golden passion fruit plantation located in eastern region of São Paulo State, Brazil, was monitored. Methods Dissemination of CABMV was determined analyzing golden passion fruit plants monthly for 18 months by PTA-ELISA. Seasonality and aphid fauna diversity was determined by ide...

  11. Feeding by the aphid Sipha flava produces a reddish spot on leaves of Sorghum halepense: an induced defense?

    Science.gov (United States)

    Costa-Arbulú, C; Gianoli, E; Gonzáles, W L; Niemeyer, H M

    2001-02-01

    Feeding by the aphid Sipha flava produces a reddish spot on mature leaves of Sorghum halepense. The present work is aimed at determining whether this plant response entails induced resistance against the aphid. Old and young leaves showed the same response to aphid feeding (reddish coloration). Water-stressed plants displayed a similar reddish coloration to aphid-infested plants. This was verified by evaluation of absorbance peaks of the respective leaf extracts. Aphid fecundity was reduced on previously infested (and hence reddish colored) leaves. However, aphid fecundity was not affected on water stressed plants. Furthermore, aphid survival was not different on artificial diets containing increasing concentrations of the reddish pigment. It is concluded that the reddish spot is correlated with, but is not itself responsible for, the observed induced resistance of S. halepense against S. flava.

  12. The genomewide transcriptional response underlying the pea aphid wing polyphenism.

    Science.gov (United States)

    Vellichirammal, Neetha N; Madayiputhiya, Nandakumar; Brisson, Jennifer A

    2016-09-01

    Phenotypic plasticity is a key life history strategy used by many plants and animals living in heterogeneous environments. A multitude of studies have investigated the costs and limits of plasticity, as well as the conditions under which it evolves. Much less well understood are the molecular genetic mechanisms that enable an organism to sense its environment and respond in a plastic manner. The pea aphid wing polyphenism is a compelling laboratory model to study these mechanisms. In this polyphenism, environmental stressors like high density cause asexual, viviparous adult female aphids to change the development of their embryos from wingless to winged morphs. The life history trade-offs between the two morphs have been intensively studied, but the molecular mechanisms underlying this process remain largely unknown. We therefore performed a genomewide study of the maternal transcriptome at two time points with and without a crowding stress to discover the maternal molecular changes that lead to the development of winged vs. wingless offspring. We observed significant transcriptional changes in genes associated with odorant binding, neurotransmitter transport, hormonal activity and chromatin remodelling in the maternal transcriptome. We also found that titres of serotonin, dopamine and octopamine were higher in solitary compared to crowded aphids. We use these results to posit a model for how maternal signals inform a developing embryo to be winged or wingless. Our findings add significant insights into the identity of the molecular mechanisms that underlie environmentally induced morph determination and suggest a possible role for biogenic amine regulation in polyphenisms generally. PMID:27393739

  13. A single genetic locus in the phytopathogen Pantoea stewartii enables gut colonization and pathogenicity in an insect host.

    Science.gov (United States)

    Stavrinides, John; No, Alexander; Ochman, Howard

    2010-01-01

    Aphids are typically exposed to a variety of epiphytic and phytopathogenic bacteria, many of which have entomopathogenic potential. Here we describe the interaction between Pantoea stewartii ssp. stewartii DC283 (DC283), an enteric phytopathogen and causal agent of Stewart's wilt, and the pea aphid, Acyrthosiphon pisum. When ingested by aphids, DC283 establishes and aggregates in the crop and gut, preventing honeydew flow and excretion, resulting in aphid death in 72 h. A mutagenesis screen identified a single locus, termed ucp1 (youcannot pass), whose disruption abolishes aphid pathogenicity. Moreover, the expression of ucp1 in Escherichia coli is sufficient to mediate the hindgut aggregation phenotype by this normally avirulent species. Ucp1 is related to six other proteins in the DC283 genome, each having a common N-terminal region and a divergent C-terminus, but only ucp1 has a role in pathogenicity. Based on predicted motifs and secondary structure, Ucp1 is a membrane-bound protein that functions in bacterial adhesion and promotes the formation of aggregates that are lethal to the insect host. These results illustrate that the enteric plant pathogenic bacteria have the capacity to exploit alternative non-plant hosts, and retain genetic determinants for colonizing the gut. PMID:19788413

  14. Experimental replacement of an obligate insect symbiont.

    Science.gov (United States)

    Moran, Nancy A; Yun, Yueli

    2015-02-17

    Symbiosis, the close association of unrelated organisms, has been pivotal in biological diversification. In the obligate symbioses found in many insect hosts, organisms that were once independent are permanently and intimately associated, resulting in expanded ecological capabilities. The primary model for this kind of symbiosis is the association between the bacterium Buchnera and the pea aphid (Acyrthosiphon pisum). A longstanding obstacle to efforts to illuminate genetic changes underlying obligate symbioses has been the inability to experimentally disrupt and reconstitute symbiont-host partnerships. Our experiments show that Buchnera can be experimentally transferred between aphid matrilines and, furthermore, that Buchnera replacement has a massive effect on host fitness. Using a recipient pea aphid matriline containing Buchnera that are heat sensitive because of an allele eliminating the heat shock response of a small chaperone, we reduced native Buchnera through heat exposure and introduced a genetically distinct Buchnera from another matriline, achieving complete replacement and stable inheritance. This transfer disrupted 100 million years (∼ 1 billion generations) of continuous maternal transmission of Buchnera in its host aphids. Furthermore, aphids with the Buchnera replacement enjoyed a dramatic increase in heat tolerance, directly demonstrating a strong effect of symbiont genotype on host ecology.

  15. Experimental replacement of an obligate insect symbiont.

    Science.gov (United States)

    Moran, Nancy A; Yun, Yueli

    2015-02-17

    Symbiosis, the close association of unrelated organisms, has been pivotal in biological diversification. In the obligate symbioses found in many insect hosts, organisms that were once independent are permanently and intimately associated, resulting in expanded ecological capabilities. The primary model for this kind of symbiosis is the association between the bacterium Buchnera and the pea aphid (Acyrthosiphon pisum). A longstanding obstacle to efforts to illuminate genetic changes underlying obligate symbioses has been the inability to experimentally disrupt and reconstitute symbiont-host partnerships. Our experiments show that Buchnera can be experimentally transferred between aphid matrilines and, furthermore, that Buchnera replacement has a massive effect on host fitness. Using a recipient pea aphid matriline containing Buchnera that are heat sensitive because of an allele eliminating the heat shock response of a small chaperone, we reduced native Buchnera through heat exposure and introduced a genetically distinct Buchnera from another matriline, achieving complete replacement and stable inheritance. This transfer disrupted 100 million years (∼ 1 billion generations) of continuous maternal transmission of Buchnera in its host aphids. Furthermore, aphids with the Buchnera replacement enjoyed a dramatic increase in heat tolerance, directly demonstrating a strong effect of symbiont genotype on host ecology. PMID:25561531

  16. Conditional Reduction of Predation Risk Associated with a Facultative Symbiont in an Insect.

    Directory of Open Access Journals (Sweden)

    Sarah Polin

    Full Text Available Symbionts are widespread among eukaryotes and their impacts on the ecology and evolution of their hosts are meaningful. Most insects harbour obligate and facultative symbiotic bacteria that can influence their phenotype. In the pea aphid Acyrthosiphon pisum, an astounding symbiotic-mediated phenotype has been recently observed: when infected with the symbiotic bacteria Rickettsiella viridis, young red aphid larvae become greener at adulthood and even darker green when co-infected with Rickettsiella viridis and Hamiltonella defensa. As body colour affects the susceptibility towards natural enemies in aphids, the influence of the colour change due to these facultative symbionts on the host survival in presence of predators was tested. Our results suggested that the Rickettsiella viridis infection may impact positively host survival by reducing predation risk. Due to results from uninfected aphids (i.e., more green ones attacked, the main assumption is that this symbiotic infection would deter the predatory ladybird feeding by reducing the profitability of their hosts rather than decreasing host detection through body colour change. Aphids co-infected with Rickettsiella viridis and Hamiltonella defensa were, however, more exposed to predation suggesting an ecological cost associated with multiple infections. The underlying mechanisms and ecological consequences of these symbiotic effects are discussed.

  17. Differential expression of superoxide dismutase genes in aphid-stressed maize (Zea mays L. seedlings.

    Directory of Open Access Journals (Sweden)

    Hubert Sytykiewicz

    Full Text Available The aim of this study was to compare the expression patterns of superoxide dismutase genes (sod2, sod3.4, sod9 and sodB in seedling leaves of the Zea mays L. Tasty Sweet (susceptible and Ambrozja (relatively resistant cultivars infested with one of two hemipteran species, namely monophagous Sitobion avenae F. (grain aphid or oligophagous Rhopalosiphum padi L. (bird cherry-oat aphid. Secondarily, aphid-elicited alternations in the antioxidative capacity towards DPPH (1,1-diphenyl-2-picrylhydrazyl radical in insect-stressed plants were evaluated. Comprehensive comparison of expression profiles of the four sod genes showed that both insect species evoked significant upregulation of three genes sod2, sod3.4 and sod9. However, aphid infestation affected non-significant fluctuations in expression of sodB gene in seedlings of both maize genotypes. The highest levels of transcript accumulation occurred at 8 h (sod2 and sod3.4 or 24 h (sod9 post-infestation, and aphid-induced changes in the expression of sod genes were more dramatic in the Ambrozja cultivar than in the Tasty Sweet variety. Furthermore, bird cherry-oat aphid colonization had a more substantial impact on levels of DPPH radical scavenging activity in infested host seedlings than grain aphid colonization. Additionally, Ambrozja plants infested by either hemipteran species showed markedly lower antioxidative capacity compared with attacked Tasty Sweet plants.

  18. Yield response of brassica varieties/strains in relation to mustard aphid lipaphis erysimi (Kalt.)

    International Nuclear Information System (INIS)

    Nine brassica varieties/advanced lines were tested to find out the varietal comparison against mustard aphid Lipaphis erysimi (kalt.) in relation to aphid population. average number of branches/plant, average number of grains per pod and grain yield (kg/ha) during 2004-2006. Minimum aphid population was observed on promising cultivar P-20 during both years 2004-2005-06 which were 2005-06 which were 31 and 23 aphid/30 cm of apical inflorescence from randomly selected five plants respectively. This promising strain also proved significantly the highest yielder and gave 1633 kg. grains/ha (2004,05) and 817.5 kg grains/ha (2005-06) followed by SP-36 which showed aphid population 36 and 32.5 aphid/30 cm inflorescence having yield 1373 and 780 kg grains/ha during the both periods respectively under report. The other parameters viz. Average number of branches per plant and average no. of grains/pod remained non significant as far as aphid effect is concerned. (author)

  19. Studies on the Host Biotypes and Its Cause of Cotton Aphid in Nanjing, China

    Institute of Scientific and Technical Information of China (English)

    LIU Xiang-dong; ZHAI Bao-ping; ZHANG Xiao-xi

    2002-01-01

    The fitness of cotton aphid, Aphis gossypii Glover, on different host plants was studied. The results showed that the cotton aphid population in Nanjing formed host preference bio-types on cucumber and cotton. The aphids from cotton and cucumber could not inter-transplant successfully between the two host plants. The apterous and alate offspring of stem mother from hibiscus could not survive, reproduce and form population normally when they were transplanted to cucumber and water melon, but they could form normally when transplanted to cotton and muskmelon. There was no significant difference between the stylet length of cotton aphids from cucumber and cotton, so the stylet length was not the cause of the host preference. When the aphids originated on hibiscus were transplanted to cotton, water melon and muskmelon, the stylet could reach host phloem to absorb host plant's nutrients, but it couldn't when transplanted to cucumber. Cotton aphid can feed on muskmelon without secretion of water-soluble saliva. It could be concluded that the two host biotypes of cotton aphid came from different winter host plants.

  20. The Temperature Response and Aggressiveness of Peyronellaea pinodes Isolates Originating from Wild and Domesticated Pisum sp. in Israel.

    Science.gov (United States)

    Golani, M; Abbo, S; Sherman, A; Frenkel, O; Shtienberg, D

    2016-08-01

    Domesticated pea fields are grown in relatively close proximity to wild pea species in Israel. Despite the major role attributed to ascochyta blight in causing yield losses in domesticated pea, very limited information is available on the pathogens prevailing in natural ecosystems. The objectives of this study were (i) to identify the species causing ascochyta blight symptoms on leaves, stems, and petioles of domesticated pea and wild Pisum plants in Israel, and (ii) to quantify the temperature response(s) and aggressiveness of such pathogens originating from Pisum plants growing in sympatric and allopatric contexts. Eighteen fungal isolates were examined and identified; three of them were sampled from Pisum sativum, 11 from Pisum fulvum, and four from Pisum elatius. All isolates were identified as Peyronellaea pinodes. Spore germination and mycelial growth took place over a wide range of temperatures, the lower and upper cardinal temperatures being 2 to 9 and 33 to 38°C, respectively; the optimal temperatures ranged from 22 to 26°C. At an optimal temperature, disease severity was significantly higher for plants maintained under moist conditions for 24 h postinoculation than for those exposed to humidity for 5 or 10 h. Analyses of the data revealed that temperature responses, spore germination rates, and aggressiveness of isolates sampled from domesticated pea plants did not differ from those of isolates sampled from adjacent or distant wild populations. Host specificity was not observed. These observations suggest that Israel may be inhabited by a single metapopulation of P. pinodes. PMID:27050578

  1. Differential Life History Trait Associations of Aphids with Nonpersistent Viruses in Cucurbits.

    Science.gov (United States)

    Angelella, G M; Egel, D S; Holland, J D; Nemacheck, J A; Williams, C E; Kaplan, I

    2015-06-01

    The diversity of vectors and fleeting nature of virus acquisition and transmission renders nonpersistent viruses a challenge to manage. We assessed the importance of noncolonizing versus colonizing vectors with a 2-yr survey of aphids and nonpersistent viruses on commercial pumpkin farms. We quantified aphid alightment using pan traps, while testing leaf samples with multiplex RT-PCR targeting cucumber mosaic virus (CMV), zucchini yellow mosaic virus (ZYMV), watermelon mosaic virus (WMV), and papaya ringspot virus (PRSV). Overall, we identified 53 aphid species (3,899 individuals), from which the melon aphid, Aphis gossypii Glover, a pumpkin-colonizing species, predominated (76 and 37% of samples in 2010 and 2011, respectively). CMV and ZYMV were not detected, but WMV and PRSV were prevalent, both regionally (WMV: 28/29 fields, PRSV: 21/29 fields) and within fields (infection rates = 69 and 55% for WMV in 2010 and 2011; 28 and 25% for PRSV in 2010 and 2011). However, early-season samples showed extremely low infection levels, suggesting cucurbit viruses are not seed-transmitted and implicating aphid activity as a causal factor driving virus spread. Interestingly, neither noncolonizer and colonizer alightment nor total aphid alightment were good predictors of virus presence, but community analyses revealed species-specific relationships. For example, cowpea aphid (Aphis craccivora Koch) and spotted alfalfa aphid (Therioaphis trifolii Monell f. maculata) were associated with PRSV infection, whereas the oleander aphid (Aphis nerii Bover de Fonscolombe) was associated with WMV spread within fields. These outcomes highlight the need for tailored management plans targeting key vectors of nonpersistent viruses in agricultural systems. PMID:26313961

  2. Changes in activity of lysine decarboxylase in winter triticale in response to grain aphid feeding.

    Science.gov (United States)

    Sempruch, C; Leszczyński, B; Wójcicka, Agnieszka; Makosz, M; Matok, H; Chrzanowski, G

    2010-12-01

    Changes in lysine decarboxylase (LDC) activity caused by Sitobion avenae (F.) feeding on two winter triticale cultivars (cvs) were studied. The aphid fecundity and values of intrinsic rate of natural increase showed that cv Witon was less susceptible to S. avenae than cv Tornado. The grain aphid feeding on more susceptible triticale caused a decrease in the LDC activity, with exceptions of root tissues after two weeks of the feeding. In case of less susceptible cv Witon reduction of the LDC activity was observed only during initial period of S. avenae feeding. Later the aphid infestation induced activity of the LDC within tissues of cv Witon. PMID:21112841

  3. Host settling behavior, reproductive performance, and effects on plant growth of an exotic cereal aphid, Metopolophium festucae subsp. cerealium (Hemiptera: Aphididae).

    Science.gov (United States)

    Davis, T S; Wu, Y; Eigenbrode, S D

    2014-06-01

    The cereal aphid Metopolophium festucae subsp. cerealium (Stroyan) is a recent addition to North America, but little is known about this species in its exotic habitat. We surveyed aphid populations for 3 years (2011-2013) to investigate changes in aphid density in the Pacific Northwest United States. We tested aphid host settling preference and fecundity on eight grass species, four native grasses (bluebunch wheatgrass, blue wild rye, Idaho fescue, and rough fescue) and four cereal crops (corn, wheat, barley, and oat), and evaluated the effects of aphid feeding on plant biomass. Four important findings emerged: 1) aphid prevalence in sweep net samples increased from 2011 to 2012, but remained stable from 2012 to 2013; 2) aphids preferentially settled on wheat and avoided corn, but aphids did not discriminate between barley, oat, and native grasses; 3) aphid fecundity was high on wheat and barley, intermediate on oat and blue wild rye, low on Idaho fescue, rough fescue, and bluebunch wheatgrass, and aphids did not reproduce at all on corn; and 4) barley, corn, oats, Idaho fescue, and blue wild rye were not susceptible to aphid feeding damage, but wheat, rough fescue, and bluebunch wheatgrass were susceptible to aphid feeding damage. Our results suggest that wheat and barley are preferred by M. festucae cerealium, and that aphids reproduce most rapidly on these hosts and cause significant reductions in wheat but not barley growth. Also, M. festucae cerealium appears capable of surviving on native grasses, although only bluebunch wheatgrass and rough fescue were susceptible to aphid feeding damage.

  4. [UV-induced DNA mutation of peach aphid].

    Science.gov (United States)

    Du, Erxia; Guo, Jianwen; Zhao, Huiyan

    2006-07-01

    By using PCR technique and microsatellite marks, this paper studied the DNA polymorphism of peach aphid (Myzus persicae) under UV-radiation. The fragments of three primers were amplified, and the gene diversity and the rate of loci polymorphisms of their genomic DNA, which could reflect the damage degree of DNA after UV-radiation, were measured. The results revealed that after treated with different radiation intensity (15, 30, 45 W) and duration (2, 4, 6 h) , the UV-induced DNA mutations were genetic and could be delivered to F2 generation. The mutations depended on the interaction of radiation intensity and duration. Variance analysis on the gene diversity and the rate of loci polymorphisms showed that there existed a significant difference between UV-treated and control groups, except the rate of loci polymorphisms under 2 h radiation. The average value of the control was higher than that of 2 h radiation treatment. According to the cluster analysis of the genetic distance, the aphids were divided into three groups, i. e., control group, 2 h (15, 30 W) treatment group, and the other, which was consistent with the result of variance analysis.

  5. Effects of some Insecticides Applied in Sublethal Concentrations on the Survival and Longevity of Aphidius ervi (Haliday (Hymenoptera: Aphidiidae Adults Efecto de algunos Insecticidas Aplicados en Concentraciones Subletales en la Supervivencia y Longevidad de Adultos de Aphidius ervi (Haliday (Hymenoptera: Aphidiidae

    Directory of Open Access Journals (Sweden)

    Jaime E. Araya

    2010-06-01

    Full Text Available The effects of four insecticides (dimethoate, pirimicarb, imidacloprid, and spinosad applied in an ST4 Potter tower at sublethal concentrations (50% of those recommended commercially for aphid control were studied in the laboratory on aphidiid Aphidius ervi (Haliday adults, an important parasitoid of the pea aphid Acyrthosiphon pisum (Harris. The most selective treatment on the hymenopteran was imidacloprid, followed in decreasing order by spinosad, pirimicarb, and finally dimethoate, which quickly eliminated the parasitoid and thus its capacity to produce progeny. Three toxicity groups were distinguished in the study. The least damaging treatment to adults of A. ervi was imidacloprid, followed by a group of medium toxicity made up of spinosad and pirimicarb, and lastly dimethoate, which was extremely toxic to A. pisum.Se evaluaron en laboratorio los efectos de cuatro insecticidas (dimetoato, pirimicarb, imidacloprid, y spinosad aplicados en torre Potter ST4 en concentraciones subletales (50% de las dosis comerciales recomendadas para el control de áfidos sobre adultos del afídido Aphidius ervi Haliday, un importante parasitoide del pulgón de la arveja Acyrthosiphon pisum (Harris. El tratamiento más selectivo sobre el himenóptero fue imidacloprid, seguido en orden decreciente por spinosad, pirimicarb, y finalmente dimetoato, compuesto que eliminó rápidamente al parasitoide y su capacidad de producir descendencia. Se distinguieron tres grupos de toxicidad. El tratamiento menos dañino para los adultos de A. ervi fue imidacloprid; seguido por un grupo de selectividad media formado por spinosad y pirimicarb; y por último dimetoato, que fue extremadamente tóxico.

  6. Relations between protein production, protein quality and environmental factors in Pisum mutants

    International Nuclear Information System (INIS)

    The seed protein content of 138 radiation-induced Pisum mutants was determined. The variability of this genetically well-defined material agrees approximately with that of the world collection of Pisum sativum. Some environmental factors to a great extent influence the protein production of the mutants and the initial line. Therefore, it is necessary to consider the relations between the genetically controlled protein production and its dependence upon the environmental factors. This is especially evident if the protein situation of the same genotypes cultivated under the moderate climatic conditions of middle Europe is compared with the subtropical conditions of India. A generally firm correlation between seed size and protein content could not be found in material regarding 148 different mutants of our assortment. Therefore, the selection of small-grained mutants does not result in a selection of protein-rich genotypes in Pisum sativum. Considering all the criteria positively and negatively influencing the protein production, a positive situation could be found in some mutants, especially in the fasciated ones. Furthermore, an improvement of the protein quality could be reached by a genetically conditioned alteration of the globulin-albumin ratio leading to an increase of some essential amino acids such as methionine and lysine. The combined action of mutant genes results in unexpected changes of the protein quantity as well as the quality of the recombinants in relation to their parental mutants. The comparison of some essential amino acids of our useful mutants with those of the varieties of other genera of the Leguminosae shows certain trends of biochemical alterations realized during evolutionary development of the family. (author)

  7. All 37 Mitochondrial Genes of Aphid Aphis craccivora Obtained from Transcriptome Sequencing: Implications for the Evolution of Aphids.

    Science.gov (United States)

    Song, Nan; Zhang, Hao; Li, Hu; Cai, Wanzhi

    2016-01-01

    The availability of mitochondrial genome data for Aphididae, one of the economically important insect pest families, in public databases is limited. The advent of next generation sequencing technology provides the potential to generate mitochondrial genome data for many species timely and cost-effectively. In this report, we used transcriptome sequencing technology to determine all the 37 mitochondrial genes of the cowpea aphid, Aphis craccivora. This method avoids the necessity of finding suitable primers for long PCRs or primer-walking amplicons, and is proved to be effective in obtaining the whole set of mitochondrial gene data for insects with difficulty in sequencing mitochondrial genome by PCR-based strategies. Phylogenetic analyses of aphid mitochondrial genome data show clustering based on tribe level, and strongly support the monophyly of the family Aphididae. Within the monophyletic Aphidini, three samples from Aphis grouped together. In another major clade of Aphididae, Pterocomma pilosum was recovered as a potential sister-group of Cavariella salicicola, as part of Macrosiphini. PMID:27314587

  8. All 37 Mitochondrial Genes of Aphid Aphis craccivora Obtained from Transcriptome Sequencing: Implications for the Evolution of Aphids.

    Directory of Open Access Journals (Sweden)

    Nan Song

    Full Text Available The availability of mitochondrial genome data for Aphididae, one of the economically important insect pest families, in public databases is limited. The advent of next generation sequencing technology provides the potential to generate mitochondrial genome data for many species timely and cost-effectively. In this report, we used transcriptome sequencing technology to determine all the 37 mitochondrial genes of the cowpea aphid, Aphis craccivora. This method avoids the necessity of finding suitable primers for long PCRs or primer-walking amplicons, and is proved to be effective in obtaining the whole set of mitochondrial gene data for insects with difficulty in sequencing mitochondrial genome by PCR-based strategies. Phylogenetic analyses of aphid mitochondrial genome data show clustering based on tribe level, and strongly support the monophyly of the family Aphididae. Within the monophyletic Aphidini, three samples from Aphis grouped together. In another major clade of Aphididae, Pterocomma pilosum was recovered as a potential sister-group of Cavariella salicicola, as part of Macrosiphini.

  9. Growth, seed development and genetic analysis in wild type and Def mutant of Pisum sativum L

    OpenAIRE

    Ayeh Kwadwo; Lee YeonKyeong; Ambrose Mike J; Hvoslef-Eide Anne

    2011-01-01

    Abstract Background The def mutant pea (Pisum sativum L) showed non-abscission of seeds from the funicule. Here we present data on seed development and growth pattern and their relationship in predicting this particular trait in wild type and mutant lines as well as the inheritance pattern of the def allele in F2 and F3 populations. Findings Pod length and seed fresh weight increase with fruit maturity and this may affect the abscission event in pea seeds. However, the seed position in either...

  10. Analysis of nucleolar pre-rRNA processing sites in pea(Pisum sativum)

    Institute of Scientific and Technical Information of China (English)

    LONG; Hong; (龙; 鸿); ZENG; Xianlu; (曾宪录); JIAO; Mingda; (焦明大); HU; Bo; (胡; 波); SUN; Haijing; (孙海晶); LIU; Zhenlan; (刘振兰); ZHANG; Liyong; (张立勇); HAO; Shui; (郝; 水)

    2003-01-01

    The location of rRNA processing was analyzed by using in situ hybridization with ITS1 probe and immunolabeling of anti-fibrillarin mAb in pea (Pisum sativum) root pole cells. The results showed that rRNA processing sites were in dense fibrillar components (DFCs) and granular components (GCs), but not in fibrillar centers (FCs). Low doses of actinomycin D (AMD) treatment can selectively suppress pre-rRNA synthesis but cannot disturb the processing of preformed pre-rRNAs. With AMD treatment prolonged, the density of labeled signals gradually decreased, indicating the preformed pre-rRNAs were gradually processed.

  11. Genetic study of pea (Pisum sativum L.) mutants with altered shape of the pod (moniliform pod)

    International Nuclear Information System (INIS)

    Mutants 1/39 and 2/179 were induced in pea cultivars Auralia and Borek after gamma-ray irradiation and temperature treatment of the seeds. The mutants were isolated in M2 generation and were characterized by altered shape of the pod. It was established that the mutants were allelic and resulted from mutation of a single recessive gene. The designation moniliform pod was proposed for the mutation type and the symbol mfp for the gene. Mutants are useful plant material for studying the genetics of the mutated trait, i.e. the shape of pod in peas (Pisum sativum L.)

  12. Isolation and Characterization of Novel EST-Derived Genic Markers in Pisum sativum (Fabaceae

    Directory of Open Access Journals (Sweden)

    Shalu Jain

    2013-10-01

    Full Text Available Premise of the study: Novel markers were developed for pea (Pisum sativum from pea expressed sequence tags (ESTs having significant homology to Medicago truncatula gene sequences to investigate genetic diversity, linkage mapping, and cross-species transferability. Methods and Results: Seventy-seven EST-derived genic markers were developed through comparative mapping between M. truncatula and P. sativum in which 75 markers produced PCR products and 33 were polymorphic among 16 pea genotypes. Conclusions: The novel markers described here will be useful for future genetic studies of P. sativum; their amplification in lentil (Lens culinaris demonstrates their potential for use in closely related species.

  13. Nitrogen and phosphorus compounds in the aleurone grains of Iris pseudoacorus endosperm and Pisum sativum cotyledons

    Directory of Open Access Journals (Sweden)

    Ligia Konopska

    2015-05-01

    Full Text Available Aleurone grains from Iris pseudoacorus endosperm and Pisum sativum cotyledons were isolated partly according to Tombs's method (1967. Nitrogen compounds content was determined in them by Kjeldahl's micromethod, and in the particular fractions after Thiman and Laloraya (1960. Mainly protein N was detected in the aleurone grains, constituting 14.8 and 15.2 per cent of the dry mass of pea and Iris seeds, respectively. Moreover, phosphorus compounds were fractionated according to Holden and Pirie (1955. Analyses demonstrated the presence in aleurone grains of inorganic P, acid-soluble organophosphorus compounds, phospholipids and RNA.

  14. Characterisation and cross-amplification of polymorphic microsatellite loci in ant-associated root-aphids

    DEFF Research Database (Denmark)

    Ivens, A.B.F.; Kronauer, Daniel Jan Christoph; Boomsma, J.J.

    2011-01-01

    Twenty-six polymorphic microsatellite loci were developed for four species of ant-associated root-aphids: Geoica utricularia, Forda marginata, Tetraneura ulmi and Anoecia corni. We found up to 9 alleles per locus, with an average of 4.8. We also report polymorphic cross-amplification of eleven...... of these markers between different pairs of study species. Furthermore, we tested previously published aphid microsatellites and found one locus developed for Pemphigus bursarius to be polymorphic in G. utricularia. These microsatellite markers will be useful to study the population structure of aphids associated...... with the ant Lasius flavus and possibly other ants. Such studies are relevant because: 1. L. flavus mounds and their associated flora and fauna are often key components in protected temperate grasslands, and 2. L. flavus and its diverse community of root-aphids provide an interesting model system for studying...

  15. Natural enemies of woolly apple aphid (Hemiptera: Aphididae) in Washington State.

    Science.gov (United States)

    Gontijo, Lessando M; Cockfield, Stephen D; Beers, Elizabeth H

    2012-12-01

    Woolly apple aphid, Eriosoma lanigerum (Hausmann), has become a pest of increasing importance in Washington apple orchards in the past decade. The increase in aphid outbreaks appears to be associated with changes in pesticide programs and disruption of biological control. We sampled woolly apple aphid colonies in central Washington apple orchards for natural enemies of this pest from 2006 to 2008. The most common predators encountered were Syrphidae (Syrphus opinator Osten Sacken, Eupeodes fumipennis Thomson, and Eupeodes americanus Wiedemann); Chrysopidae (Chrysopa nigricornis Burmeister); and Coccinellidae (Coccinella transversoguttata Brown and Hippodamia convergens Guérin-Méneville). The specialist syrphid Heringia calcarata Loew was recorded for the first time occurring in Washington apple orchards. The only parasitoid found in aerial colonies of woolly apple aphid was Aphelinus mali Haldeman; root colonies, however, were not parasitized. Identification of important natural enemies provides a better basis for conservation biological control of this pest.

  16. Reproduction and dispersal in an ant-associated root aphid community

    DEFF Research Database (Denmark)

    Ivens, A.B.F.; Kronauer, Daniel Jan Christoph; Pen, I.;

    2012-01-01

    above ground, whereas dispersal constraints and dependence on ant-tending may differentially affect the costs and benefits of sex in subterranean aphids. Here, we studied reproductive mode and dispersal in a community of root aphids that are obligately associated with the ant Lasius flavus. We assessed...... viscosity is high and winged aphids rare, consistent with infrequent horizontal transmission between ant host colonies. The absence of the primary host shrub (Pistacia) may explain the absence of sex in three of the studied species, but elm trees (Ulmus) that are primary hosts of the fourth species (T....... ulmi) occurred within a few km of the study population. We discuss the extent to which obligate ant-tending and absence of primary hosts may have affected selection for permanent parthenogenesis, and we highlight the need for further study of these aphids in Southern Europe where primary hosts may occur close...

  17. Kaolin particle films suppress many apple pests, disrupt natural enemies and promote woolly apple aphid

    NARCIS (Netherlands)

    Markó, V.; Blommers, L.H.M.; Bogya, S.; Helsen, H.H.M.

    2008-01-01

    Multiple applications of hydrophobic kaolin particle film in apple orchards suppressed numbers of blossom weevil (Anthonomus pomorum), brown leaf weevil (Phyllobius oblongus), attelabid weevil (Caenorhinus pauxillus), leafhoppers (Empoasca vitis and Zygina flammigera) and green apple aphid (Aphis po

  18. Tracking the global dispersal of a cosmopolitan insect pest, the peach potato aphid

    Directory of Open Access Journals (Sweden)

    Kasprowicz Louise

    2009-05-01

    Full Text Available Abstract Background Global commerce and human transportation are responsible for the range expansion of various insect pests such as the plant sucking aphids. High resolution DNA markers provide the opportunity to examine the genetic structure of aphid populations, identify aphid genotypes and infer their evolutionary history and routes of expansion which is of value in developing management strategies. One of the most widespread aphid species is the peach-potato aphid Myzus persicae, which is considered as a serious pest on various crops in many parts of the world. The present study examined the genetic variation of this aphid at a world scale and then related this to distribution patterns. In particular, 197 aphid parthenogenetic lineages from around the world were analysed with six microsatellite loci. Results Bayesian clustering and admixture analysis split the aphid genotypes into three genetic clusters: European M. persicae persicae, New Zealand M. persicae persicae and Global M. persicae nicotianae. This partition was supported by FST and genetic distance analyses. The results showed two further points, a possible connection between genotypes found in the UK and New Zealand and globalization of nicotianae associated with colonisation of regions where tobacco is not cultivated. In addition, we report the presence of geographically widespread clones and for the first time the presence of a nicotianae genotype in the Old and New World. Lastly, heterozygote deficiency was detected in some sexual and asexual populations. Conclusion The study revealed important genetic variation among the aphid populations we examined and this was partitioned according to region and host-plant. Clonal selection and gene flow between sexual and asexual lineages are important factors shaping the genetic structure of the aphid populations. In addition, the results reflected the globalization of two subspecies of M. persicae with successful clones being spread at

  19. Tracking the global dispersal of a cosmopolitan insect pest, the peach potato aphid

    Science.gov (United States)

    Margaritopoulos, John T; Kasprowicz, Louise; Malloch, Gaynor L; Fenton, Brian

    2009-01-01

    Background Global commerce and human transportation are responsible for the range expansion of various insect pests such as the plant sucking aphids. High resolution DNA markers provide the opportunity to examine the genetic structure of aphid populations, identify aphid genotypes and infer their evolutionary history and routes of expansion which is of value in developing management strategies. One of the most widespread aphid species is the peach-potato aphid Myzus persicae, which is considered as a serious pest on various crops in many parts of the world. The present study examined the genetic variation of this aphid at a world scale and then related this to distribution patterns. In particular, 197 aphid parthenogenetic lineages from around the world were analysed with six microsatellite loci. Results Bayesian clustering and admixture analysis split the aphid genotypes into three genetic clusters: European M. persicae persicae, New Zealand M. persicae persicae and Global M. persicae nicotianae. This partition was supported by FST and genetic distance analyses. The results showed two further points, a possible connection between genotypes found in the UK and New Zealand and globalization of nicotianae associated with colonisation of regions where tobacco is not cultivated. In addition, we report the presence of geographically widespread clones and for the first time the presence of a nicotianae genotype in the Old and New World. Lastly, heterozygote deficiency was detected in some sexual and asexual populations. Conclusion The study revealed important genetic variation among the aphid populations we examined and this was partitioned according to region and host-plant. Clonal selection and gene flow between sexual and asexual lineages are important factors shaping the genetic structure of the aphid populations. In addition, the results reflected the globalization of two subspecies of M. persicae with successful clones being spread at various scales throughout the

  20. Population dynamics of rose aphid Macrosiphum rosae L. on different cultivars of Rosa indica L. in Pakistan

    International Nuclear Information System (INIS)

    The research was carried out at the Pir Mehr Ali Shah-Arid Agriculture University, Rawalpindi research field area on rose plants for rose aphid populations during 2008-09. Data were recorded on weekly basis. Nymphs, winged and wingless adults were counted from leaves (upper, middle and lower leaves), buds and flowers by visual observation from tagged plants. Aphid populations start to develop in November and its population decline with decline in temperature in December. While its population started rising again at the end of February. Significantly more aphid populations were observed on Perfecta than other varieties; however, significantly few aphids were observed on Christan Diar. These studies revealed that farmers growing roses on a commercial scale should grow Christan Diar to avoid aphid attack. Maximum average number of aphid nymph, winged and wingeless adults on leaves, buds and flowers were 11.11, 4.97 and 10.13, respectively observed on Perfecta variety. (author)

  1. Aphids (Homoptera, Aphidodea inhabiting the trees Crataegus x media Bechst. in the urban green area. Part I. The population dynamics

    Directory of Open Access Journals (Sweden)

    Bożena Jaśkiwicz

    2013-12-01

    Full Text Available The studies were conducted in the years 1999-2001 in the green areas of Lublin, on the trees of Crataegus x media Bechst. The purpose of the studies was to establish the species composition and the population dynamics of aphids inhabiting hawthorn in the street and park sites. The studies found out the presence of four aphid species on the examined trees, namely Aphis pomi De Geer, aphids from the genus Dysaphis Börn., Ovatus crataegarius (Walk. and Rhopalosiphum insertum (Walk.. More aphid species and bigger populations were found in the street site (A as compa red with the park site (B.The weather conditions (air temperatures of over 30°C and stormy rainfalls limited the population of all aphid species. On the other hand, a mild winter and a warm spring with the rainfalls within the norm caused that the number of aphids decreased considerably.

  2. Expression Profiling of Selected Glutathione Transferase Genes in Zea mays (L.) Seedlings Infested with Cereal Aphids

    OpenAIRE

    Hubert Sytykiewicz; Grzegorz Chrzanowski; Paweł Czerniewicz; Iwona Sprawka; Iwona Łukasik; Sylwia Goławska; Cezary Sempruch

    2014-01-01

    The purpose of this report was to evaluate the expression patterns of selected glutathione transferase genes (gst1, gst18, gst23 and gst24) in the tissues of two maize (Zea mays L.) varieties (relatively resistant Ambrozja and susceptible Tasty Sweet) that were colonized with oligophagous bird cherry-oat aphid (Rhopalosiphum padi L.) or monophagous grain aphid (Sitobion avenae L.). Simultaneously, insect-triggered generation of superoxide anion radicals (O2 •−) in infested Z. mays plants was ...

  3. Sugarcane Aphid (Hemiptera: Aphididae): Host Range and Sorghum Resistance Including Cross-Resistance From Greenbug Sources.

    Science.gov (United States)

    Armstrong, J Scott; Rooney, William L; Peterson, Gary C; Villenueva, Raul T; Brewer, Michael J; Sekula-Ortiz, Danielle

    2015-04-01

    The graminous host range and sources of sorghum [Sorghum bicolor (L.) Moench.] plant resistance, including cross-resistance from greenbug, Schizaphis graminum (Rondani), were studied for the newly emerging sugarcane aphid, Melanaphis sacchari (Zehntner), in greenhouse no-choice experiments and field evaluations. The sugarcane aphid could not survive on field corn, Zea mays (L.), Teff grass, Eragrostis tef (Zucc.), proso millet, Panicum miliaceum L., barley, Hordeum vulgare L., and rye, Secale cereale L. Only sorghum genotypes served as hosts including Johnsongrass, Sorghum halepense (L.), a highly suitable noncrop host that generates high numbers of sugarcane aphid and maintains moderate phenotypic injury. The greenbug-resistant parental line RTx2783 that is resistant to greenbug biotypes C and E was resistant to sugarcane aphid in both greenhouse and field tests, while PI 55607 greenbug resistant to biotypes B, C, and E was highly susceptible. PI 55610 that is greenbug resistant to biotypes B, C, and E maintained moderate resistance to the sugarcane aphid, while greenbug-resistant PI 264453 was highly susceptible to sugarcane aphid. Two lines and two hybrids from the Texas A&M breeding program B11070, B11070, AB11055-WF1-CS1/RTx436, and AB11055-WF1-CS1/RTx437 were highly resistant to sugarcane aphid, as were parental types SC110, SC170, and South African lines Ent62/SADC, (Macia/TAM428)-LL9, (SV1*Sima/IS23250)-LG15. Tam428, a parental line that previously showed moderate resistance in South Africa and India, also showed moderate resistance in these evaluations. Overall, 9 of 20 parental sorghum entries tested for phenotypic damage in the field resulted in good resistance to the sugarcane aphid and should be utilized in breeding programs that develop agronomically acceptable sorghums for the southern regions of the United States.

  4. Species diversity and abundance of aphids and their natural enemies in a crop association

    OpenAIRE

    Chevalier Mendes Lopes, Thomas; Hatt, Séverin; Starý, Petr; JAPOSHVILI, George; Francis, Frédéric

    2015-01-01

    Crop associations can be efficient to reduce aphid populations, by disrupting the visual and olfactory location of host plants. However, increasing the chemical and structural complexity of vegetation can also decrease the searching efficiency of predators and parasitoids, which are not always more abundant in complex habitats. Using attractive semiochemicals such as methyl salicylate (MeSA) combined with a crop association seems promising to maximise aphid control. We compared the abundances...

  5. Selective and Irreversible Inhibitors of Aphid Acetylcholinesterases: Steps Toward Human-Safe Insecticides

    OpenAIRE

    Yuan-Ping Pang; Singh, Sanjay K.; Yang Gao; T Leon Lassiter; MISHRA, Rajesh K.; Kun Yan Zhu; Stephen Brimijoin

    2009-01-01

    Aphids, among the most destructive insects to world agriculture, are mainly controlled by organophosphate insecticides that disable the catalytic serine residue of acetylcholinesterase (AChE). Because these agents also affect vertebrate AChEs, they are toxic to non-target species including humans and birds. We previously reported that a cysteine residue (Cys), found at the AChE active site in aphids and other insects but not mammals, might serve as a target for insect-selective pesticides. Ho...

  6. Deep sequencing of the transcriptomes of soybean aphid and associated endosymbionts.

    Directory of Open Access Journals (Sweden)

    Sijun Liu

    Full Text Available BACKGROUND: The soybean aphid has significantly impacted soybean production in the U.S. Transcriptomic analyses were conducted for further insight into leads for potential novel management strategies. METHODOLOGY/PRINCIPAL FINDINGS: Transcriptomic data were generated from whole aphids and from 2,000 aphid guts using an Illumina GAII sequencer. The sequence data were assembled de novo using the Velvet assembler. In addition to providing a general overview, we demonstrate (i the use of the Multiple-k/Multiple-C method for de novo assembly of short read sequences, followed by BLAST annotation of contigs for increased transcript identification: From 400,000 contigs analyzed, 16,257 non-redundant BLAST hits were identified; (ii analysis of species distributions of top non-redundant hits: 80% of BLAST hits (minimum e-value of 1.0-E3 were to the pea aphid or other aphid species, representing about half of the pea aphid genes; (iii comparison of relative depth of sequence coverage to relative transcript abundance for genes with high (membrane alanyl aminopeptidase N or low transcript abundance; (iv analysis of the Buchnera transcriptome: Transcripts from 57.6% of the genes from Buchnera aphidicola were identified; (v identification of Arsenophonus and Wolbachia as potential secondary endosymbionts; (vi alignment of full length sequences from RNA-seq data for the putative salivary gland protein C002, the silencing of which has potential for aphid management, and the putative Bacillus thuringiensis Cry toxin receptors, aminopeptidase N and alkaline phosphatase. CONCLUSIONS/SIGNIFICANCE: THIS STUDY PROVIDES THE MOST COMPREHENSIVE DATA SET TO DATE FOR SOYBEAN APHID GENE EXPRESSION: This work also illustrates the utility of short-read transcriptome sequencing and the Multiple-k/Multiple-C method followed by BLAST annotation for rapid identification of target genes for organisms for which reference genome sequences are not available, and extends the utility

  7. Methodology of rearing of viruliferous population of aphid Rhopalosiphum padi, as a vector of Barley yellow dwarf virus (BYDV)

    OpenAIRE

    Štolcová, Jindra; Červená, Zuzana; Bártová, Šárka; Chrpová, Jana; Kumar, Jiban

    2012-01-01

    The methodology describes innovative procedures of rearing virulent population of Rhopalosiphum padi aphids, as a vector of Barley yellow dwarf virus (BYDV), for artificial infections of cereals. The method is a modification of existing procedure used in our laboratory for this purpose. The advantage of present methodology includes more abundance of viruliferous aphids within shorter period and effective control against aphid predators than the earlier used methodology.

  8. Biological control of aphids in wheat and vegetable crops : a multi-approach case study in Shandong province (China)

    OpenAIRE

    Chevalier Mendes Lopes, Thomas; Bosquée, Emilie; Chen, Julian; Yong, Liu; Bragard, Claude; Francis, Frédéric

    2014-01-01

    This multi-approach study was conducted in the Shandong province (China) to assess the effectiveness of different biological control methods against aphids in wheat and vegetable crops. Three approaches were tested: (1) wheat/oilseed rape and wheat/pea associations, (2) potatoes/peas association, and (3) E-β-farnesene (aphid alarm pheromone) releasers in squashes under plastic tunnels. Aphids and aphidophagous beneficials were monitored by observations on plants. Wheat associations and E-β-fa...

  9. Richness and diversity of aphids (Homoptera, Aphididae) along an altitudinal gradient in the Serra do Mar, Paraná, Brazil

    OpenAIRE

    Crisleide Maria Lazzarotto; Sonia Maria Noemberg Lázzari

    1998-01-01

    The lack of bioecological studies on aphids in regions with complex floristic and faunistic structure, such as the Atlantic Tropical Rain Forest, lead to the initiation of this research. The objectives were to determine species richness and diversity of aphids and to investigate the influence of altitude and environmental perturbations on aphid populations. The collections were made with yellow pan traps at 11 sites with altitudes from -10 m to 1000 m above sea level (a.s.l.), in the Serra do...

  10. A new approach for the identification of aphid vectors (Hemiptera: Aphididae) of potato virus Y.

    Science.gov (United States)

    Pelletier, Y; Nie, X; Giguère, M A; Nanayakkara, U; Maw, E; Foottit, R

    2012-12-01

    Potato virus Y (PVY) is one of the most economically important viruses affecting potato crops worldwide. PVY can be transmitted from potato to potato by several aphid species, most of which do not colonize the potato crop. New methods including preservation of viral RNA on stylets of aphids collected from yellow pan trap samples, polymerase chain reaction detection of PVY from the stylets of one aphid, and aphid identification using DNA barcoding were used to identify possible PVY vectors from field samples. In total, 65 aphid taxa were identified from the samples that tested positive for PVY. Among those, 45 taxa had never been evaluated for their ability to transmit PVY, and 7 were previously labeled as nonvectors. These results demonstrated that the list of PVY vectors is likely longer than previously reported and that most (if not all) species of aphids could be considered as potential vectors. This premise has important implications in the management of PVY in seed potato production. PMID:23356053

  11. Activation of defense mechanism in wheat by polyphenol oxidase from aphid saliva.

    Science.gov (United States)

    Ma, Rui; Chen, Ju-Lian; Cheng, Deng-Fa; Sun, Jing-Rui

    2010-02-24

    The saliva of two cereal aphids, Sitobion avenae and Schizaphis graminum in third-instar nymphs, was collected after 24 h of feeding by 30 aphids, separately, on artificial diet sachets, and the salivary enzymes were determined. The result showed that polyphenol oxidase (PPO) existed in the saliva of both aphid species, and the enzymatic activities were 6.2 x 10(-3) U/g for S. avenae and 2.37 x 10(-1) U/g for S. graminum, revealing a 38-fold higher activity in the saliva of S. graminum than in the saliva of S. avenae. It was speculated that the higher PPO activity in S. graminum saliva was a contributing factor to the light yellow spot left on the feeding site of the wheat leaf by S. graminum; no such spot was left by S. avenae. After treatment of a wheat seedling with the saliva of S. avenae and S. graminum and PPO at the concentration of aphid saliva, transcript profiling data showed that aphid saliva and PPO significantly induced expression of the genes aos and fps. Because genes aos and fps encode the key enzymes in the defense signal pathways jasmonic acid and terpene signal pathways, respectively, it was deduced that PPO from aphid saliva, as the main elicitor, triggers an appropriate defense response in wheat through jasmonic acid and terpene signal pathways. PMID:20112908

  12. Expression profiling of selected glutathione transferase genes in Zea mays (L. seedlings infested with cereal aphids.

    Directory of Open Access Journals (Sweden)

    Hubert Sytykiewicz

    Full Text Available The purpose of this report was to evaluate the expression patterns of selected glutathione transferase genes (gst1, gst18, gst23 and gst24 in the tissues of two maize (Zea mays L. varieties (relatively resistant Ambrozja and susceptible Tasty Sweet that were colonized with oligophagous bird cherry-oat aphid (Rhopalosiphum padi L. or monophagous grain aphid (Sitobion avenae L.. Simultaneously, insect-triggered generation of superoxide anion radicals (O2•- in infested Z. mays plants was monitored. Quantified parameters were measured at 1, 2, 4, 8, 24, 48 and 72 h post-initial aphid infestation (hpi in relation to the non-infested control seedlings. Significant increases in gst transcript amounts were recorded in aphid-stressed plants in comparison to the control seedlings. Maximal enhancement in the expression of the gst genes in aphid-attacked maize plants was found at 8 hpi (gst23 or 24 hpi (gst1, gst18 and gst24 compared to the control. Investigated Z. mays cultivars formed excessive superoxide anion radicals in response to insect treatments, and the highest overproduction of O2•- was noted 4 or 8 h after infestation, depending on the aphid treatment and maize genotype. Importantly, the Ambrozja variety could be characterized as having more profound increments in the levels of gst transcript abundance and O2•- generation in comparison with the Tasty Sweet genotype.

  13. Expression profiling of selected glutathione transferase genes in Zea mays (L.) seedlings infested with cereal aphids.

    Science.gov (United States)

    Sytykiewicz, Hubert; Chrzanowski, Grzegorz; Czerniewicz, Paweł; Sprawka, Iwona; Łukasik, Iwona; Goławska, Sylwia; Sempruch, Cezary

    2014-01-01

    The purpose of this report was to evaluate the expression patterns of selected glutathione transferase genes (gst1, gst18, gst23 and gst24) in the tissues of two maize (Zea mays L.) varieties (relatively resistant Ambrozja and susceptible Tasty Sweet) that were colonized with oligophagous bird cherry-oat aphid (Rhopalosiphum padi L.) or monophagous grain aphid (Sitobion avenae L.). Simultaneously, insect-triggered generation of superoxide anion radicals (O2•-) in infested Z. mays plants was monitored. Quantified parameters were measured at 1, 2, 4, 8, 24, 48 and 72 h post-initial aphid infestation (hpi) in relation to the non-infested control seedlings. Significant increases in gst transcript amounts were recorded in aphid-stressed plants in comparison to the control seedlings. Maximal enhancement in the expression of the gst genes in aphid-attacked maize plants was found at 8 hpi (gst23) or 24 hpi (gst1, gst18 and gst24) compared to the control. Investigated Z. mays cultivars formed excessive superoxide anion radicals in response to insect treatments, and the highest overproduction of O2•- was noted 4 or 8 h after infestation, depending on the aphid treatment and maize genotype. Importantly, the Ambrozja variety could be characterized as having more profound increments in the levels of gst transcript abundance and O2•- generation in comparison with the Tasty Sweet genotype. PMID:25365518

  14. In vitro interactions of the aphid endosymbiotic SymL chaperonin with barley yellow dwarf virus.

    Science.gov (United States)

    Filichkin, S A; Brumfield, S; Filichkin, T P; Young, M J

    1997-01-01

    Barley yellow dwarf virus (BYDV)-vector relationships suggest that there are specific interactions between BYDV virions and the aphid's cellular components. However, little is known about vector factors that mediate virion recognition, cellular trafficking, and accumulation within the aphid. Symbionins are molecular chaperonins produced by intracellular endosymbiotic bacteria and are the most abundant proteins found in aphids. To elucidate the potential role of symbionins in BYDV transmission, we have isolated and characterized two new symbionin symL genes encoded by the endosymbionts which are harbored by the BYDV aphid vectors Rhopalosiphum padi and Sitobion avenae. Endosymbiont symL-encoded proteins have extensive homology with the pea aphid SymL and Escherichia coli GroEL chaperonin. Recombinant and native SymL proteins can be assembled into oligomeric complexes which are similar to the GroEL oligomer. R. padi SymL protein demonstrates an in vitro binding affinity for BYDV and its recombinant readthrough polypeptide. In contrast to the R. padi SymL, the closely related GroEL does not exhibit a significant binding affinity either for BYDV or for its recombinant readthrough polypeptide. Comparative sequence analysis between SymL and GroEL was used to identify potential SymL-BYDV binding sites. Affinity binding of SymL to BYDV in vitro suggests a potential involvement of endosymbiotic chaperonins in interactions with virions during their trafficking through the aphid. PMID:8985385

  15. Aphid and ladybird beetle abundance depend on the interaction of spatial effects and genotypic diversity.

    Science.gov (United States)

    Genung, Mark A; Crutsinger, Gregory M; Bailey, Joseph K; Schweitzer, Jennifer A; Sanders, Nathan J

    2012-01-01

    Intraspecific variation and genotypic diversity of host-plants can affect the structure of associated arthropod communities and the dynamics of populations. Similarly, neighboring plants can also affect interactions between host-plants and their associated arthropods. However, most studies on the effects of host-plant genotypes have largely ignored the potential effects of neighboring host-plants on arthropod communities. In this study, we used a common garden experiment to ask how spatial effects of neighboring patches, along with genotype identity and genotypic diversity in tall goldenrod (Solidago altissima), affect the abundances of a common goldenrod herbivore (Uroleucon nigrotuberculatum) and their dominant predator (Harmonia axyridis, a ladybird beetle). Aphid abundance varied 80-fold among genotypes, while ladybird beetle abundance was not affected by genotype identity. Additionally, there were strong effects of neighboring plots: aphid abundance in a focal plot was positively correlated to aphid abundance in nearby plots, suggesting strong spatial patterning in the abundance of aphids. Neither aphid nor ladybird beetle abundance was affected by genotypic diversity. However, focal plot genotypic diversity mediated the strength of the neighborhood effect (i.e., strong effects for genotype polyculture focal plots and weak effects for genotype monoculture focal plots). Our results show that aphids were directly influenced by host-plant genotype identity while ladybird beetles responded mainly to prey abundance, and suggest that genotypic diversity can influence the effects of spatial processes on the plant-herbivore interactions. PMID:21805301

  16. Alternaria toxin-induced resistance against rose aphids and olfactory response of aphids to toxin-induced volatiles of rose plants

    Institute of Scientific and Technical Information of China (English)

    Fa-zhong YANG; Li LI; Bin YANG

    2012-01-01

    The search for active toxins for managing weeds or plant diseases is believed to be a promising avenue of investigation.However,the effects of Alternaria toxins on insects have just begun to be investigated.Bioactivities of toxins from four strains of Alternaria alternata on Rosa chinensis and rose aphid Macrosiphum rosivorum were tested in the present study.At a concentration of 50.0 μg/ml,the crude extract (toxin) of strain 7484 was found not to be harmful to rose plants with excised leaf-puncture method (P≥0.079),and rose plants showed enhanced resistance to rose aphids when this Alternaria toxin was sprayed on the plants (P≤0.001).However,this toxin caused no detrimental effects on aphids in insecticidal bioassay at a concentration of 10.0 to 160.0 μg/ml (P≥0.096).Therefore,the Alternaria toxin had significantly induced the resistance of rose plants against rose aphids,demonstrating that the resistance mechanism triggered by the Altemaria toxin in the rose plant may also be used by the plant to defend itself against insects.Further bioassays aimed to discover the olfactory responses of aphids to the toxin-induced volatiles of host plants.The aphids were significantly more attracted to both volatiles emitted and collected from control rose plants than to both volatiles emitted and collected from the toxin-treated rose plants (P≤0.014).This result showed that the toxin-induced resistance related to the volatile changes of host plants.

  17. Characterization of the natural enemy community attacking cotton aphid in the Bt cotton ecosystem in Northern China.

    Science.gov (United States)

    Ali, Abid; Desneux, Nicolas; Lu, Yanhui; Liu, Bing; Wu, Kongming

    2016-01-01

    Planting Bt cotton in China since 1997 has led to important changes in the natural enemy communities occurring in cotton, however their specific effect on suppressing the cotton aphids (being notorious in conventional cotton ecosystem) has not been fully documented yet. We observed strong evidence for top-down control of the aphid population, e.g. the control efficiency of natural enemies on cotton aphid increased significantly in open field cages compared to exclusion cages, accounted for 60.2, 87.2 and 76.7% in 2011, 2012 and 2013 season, respectively. The cotton aphid populations peaked in early June to late July (early and middle growth stages) in open field cotton survey from 2011 to 2013. The population densities of cotton aphids and natural enemies were highest on middle growth stage while lowest densities were recorded on late stage for aphids and on early plant stage for natural enemies. Aphid parasitoids (Trioxys spp., Aphidius gifuensis), coccinellids and spiders were key natural enemies of cotton aphid. Briefly, natural enemies can suppress aphid population increase from early to middle plant growth stages by providing biocontrol services in Chinese Bt cotton. PMID:27075171

  18. The effect of plant inbreeding and stoichiometry on interactions with herbivores in nature: Echinacea angustifolia and its specialist aphid.

    Directory of Open Access Journals (Sweden)

    Caroline E Ridley

    Full Text Available Fragmentation of once widespread communities may alter interspecific interactions by changing genetic composition of interacting populations as well as their abundances and spatial distributions. In a long-term study of a fragmented population of Echinacea angustifolia, a perennial plant native to the North American prairie, we investigated influences on its interaction with a specialist aphid and tending ants. We grew plant progeny of sib-matings (I, and of random pairings within (W and between (B seven remnants in a common field within 8 km of the source remnants. During the fifth growing season, we determined each plant's burden of aphids and ants, as well as its size and foliar elemental composition (C, N, P. We also assayed composition (C, N of aphids and ants. Early in the season, progeny from genotypic classes B and I were twice as likely to harbor aphids, and in greater abundance, than genotypic class W; aphid loads were inversely related to foliar concentration of P and positively related to leaf N and plant size. At the end of the season, aphid loads were indistinguishable among genotypic classes. Ant abundance tracked aphid abundance throughout the season but showed no direct relationship with plant traits. Through its potential to alter the genotypic composition of remnant populations of Echinacea, fragmentation can increase Echinacea's susceptibility to herbivory by its specialist aphid and, in turn, perturb the abundance and distribution of aphids.

  19. Assessment of patch quality by aphidophagous ladybirds: laboratory study on the minimum density of aphids required for oviposition

    Directory of Open Access Journals (Sweden)

    B. C. Das

    2011-12-01

    Full Text Available Many studies indicate that there is a density of aphids below which ladybirds are unlikely to lay eggs. This is adaptive as theory indicates that a certain minimum population density of aphids is required if hatchling larvae are to survive. The responses of gravid females of the two spot ladybird, Adalia bipunctata (L. (Coleoptera: Coccinellidae, recorded over a period of an hour, to colonies of 5 and 50 pea aphids on bean plants and similar plants each previously infested with the same number of aphids for 48 hours were determined. Proportionally more of the ladybirds on plants with 50 aphids or that were previously infested with the same number of aphids for 48 hours laid eggs and larger clusters of eggs, and were less active than those on plants that were infested with or had previously been infested with five aphids. That is, gravid females showed similar oviposition and activity responses to aphid abundance and different levels of honeydew contamination. This indicates that honeydew contamination may be an important cue used by ladybirds when locating and assessing the abundance of prey in aphid colonies.

  20. Effect of clinorotation on the leaf mesophyll structure and pigment content in Arabidopsis thaliana L. and Pisum sativum L.

    Science.gov (United States)

    Adamchuk, N I

    2004-07-01

    Properties of mesophyll cells and photosynthetic membranes of Arabidopsis thaliana (L.) Heynh. and Pisum sativum (L.) plants grown in a horizontal clinostat and in control conditions were compared. Obtained data have show that under clinorotation conditions seedlings have experienced the following cell morphology changes structural chloroplast rearrangement in palisade cells, pigment content alteration, and cell aging acceleration.

  1. Calcium-calmodulin signalling is involved in light-induced acidification by epidermal leaf cells of pea, Pisum sativum L.

    NARCIS (Netherlands)

    Elzenga, JTM; Staal, M; Prins, HBA

    1997-01-01

    Pathways of signal transduction of red and blue light-dependent acidification by leaf epidermal cells were studied using epidermal strips of the Argenteum mutant of Pisum sativum. In these preparations the contribution of guard cells to the acidification is minimal. The hydroxypyridine nifedipine, a

  2. Water stress modulates soybean aphid performance, feeding behavior and virus transmission in soybean

    Directory of Open Access Journals (Sweden)

    Punya eNachappa

    2016-04-01

    Full Text Available Little is known about how water stress including drought and flooding modifies the ability of plants to resist simultaneous attack by insect feeding and transmission of insect-vectored pathogen. We analyzed insect population growth, feeding behaviors, virus transmission, and plant amino acid profiles and defense gene expression to characterize mechanisms underlying the interaction between water stress, soybean aphid and aphid-transmitted, Soybean mosaic virus, on soybean plants. Population growth of non-viruliferous aphids was reduced under drought stress and saturation, likely because the aphids spent less time feeding from the sieve element on these plants compared to well-watered plants. Water stress did not impact population growth of viruliferous aphids. However, virus incidence and transmission rate was lowest under drought stress and highest under saturated conditions since viruliferous aphids took the greatest amount time to puncture cells and transmit the virus under saturated conditions and lowest time under drought stress. Petiole exudates from drought-stressed plants had the highest level of total free amino acids including asparagine and valine that are critical for aphid performance. Aphids did not benefit from improved phloem sap quality as indicated by their lower densities on drought-stressed plants. Saturation, on the other hand, resulted in low amino acid content compared to all of the other treatments. Drought and saturation had significant and opposing effects on expression of marker genes involved in abscisic acid (ABA signaling. Drought alone significantly increased expression of ABA marker genes, which likely led to suppression of salicylic acid (SA- and jasmonic acid (JA-related genes. In contrast, ABA marker genes were down-regulated under saturation, while expression of SA- and JA-related genes was up-regulated. We propose that the apparent antagonism between ABA and SA/JA signaling pathways contributed to an increase

  3. Water Stress Modulates Soybean Aphid Performance, Feeding Behavior, and Virus Transmission in Soybean.

    Science.gov (United States)

    Nachappa, Punya; Culkin, Christopher T; Saya, Peter M; Han, Jinlong; Nalam, Vamsi J

    2016-01-01

    Little is known about how water stress including drought and flooding modifies the ability of plants to resist simultaneous attack by insect feeding and transmission of insect-vectored pathogen. We analyzed insect population growth, feeding behaviors, virus transmission, and plant amino acid profiles and defense gene expression to characterize mechanisms underlying the interaction between water stress, soybean aphid and aphid-transmitted, Soybean mosaic virus, on soybean plants. Population growth of non-viruliferous aphids was reduced under drought stress and saturation, likely because the aphids spent less time feeding from the sieve element on these plants compared to well-watered plants. Water stress did not impact population growth of viruliferous aphids. However, virus incidence and transmission rate was lowest under drought stress and highest under saturated conditions since viruliferous aphids took the greatest amount time to puncture cells and transmit the virus under saturated conditions and lowest time under drought stress. Petiole exudates from drought-stressed plants had the highest level of total free amino acids including asparagine and valine that are critical for aphid performance. Aphids did not benefit from improved phloem sap quality as indicated by their lower densities on drought-stressed plants. Saturation, on the other hand, resulted in low amino acid content compared to all of the other treatments. Drought and saturation had significant and opposing effects on expression of marker genes involved in abscisic acid (ABA) signaling. Drought alone significantly increased expression of ABA marker genes, which likely led to suppression of salicylic acid (SA)- and jasmonic acid (JA)-related genes. In contrast, ABA marker genes were down-regulated under saturation, while expression of SA- and JA-related genes was up-regulated. We propose that the apparent antagonism between ABA and SA/JA signaling pathways contributed to an increase in aphid

  4. Quantification of insecticide resistance in the tobacco-adapted form of the green peach aphid, Myzus persicae (Sulzer)(Hemiptera: Aphididae)

    OpenAIRE

    Srigiriraju, Lakshmipathi

    2008-01-01

    The tobacco-adapted form of the green peach aphid, Myzus persicae (Sulzer), is one of the most important insect pests of tobacco in the United States and around the world. Insecticides play a major role in controlling the aphid on tobacco because natural enemies usually fail to maintain its populations below damaging levels. The aphid has a history of developing resistance to many insecticides. Therefore, baseline information on the aphidâ s susceptibility to imidacloprid and other insect...

  5. Shallot aphids, Myzus ascalonicus, in strawberry: biocontrol potential of three predators and three parasitoids.

    Science.gov (United States)

    Enkegaard, Annie; Sigsgaard, Lene; Kristensen, Kristian

    2013-01-01

    The parasitization capacity of 3 parasitoids and the predation capacity of 3 predators towards the shallot aphid, Myzus ascalonicus Doncaster (Homoptera: Aphididae), on strawberry, Fragaria x ananassa Duchesne (Rosales: Rosaceae) cv. Honeoye, were examined in laboratory experiments. In Petri dish assays, both Aphidius colemani Viereck (Hymenoptera: Aphidiidae) and A. ervi Haliday readily stung shallot aphids, with no significant difference in stinging frequency between the two species. A. ervi induced a significantly higher mortality (79.0 ± 7.2%) in terms of stung aphids compared with A. colemani (55.3 ± 4.1%); however, only a minor fraction (2.7 ± 1.8% and 7.1 ± 3.1%, respectively) of the killed aphids resulted in formation of mummies, presumably due to a physiological response to parasitism. The low percentage of mummification precludes the use of either Aphidius species in anything but inundative biocontrol. In similar set-ups, Aphelinus abdominalis (Dalman) (Hymenoptera: Aphelinidae) killed almost half (49.6 ± 5.3%) of the exposed aphids through host feeding. In addition, 23.2 ± 7.3% of non-host-fed aphids developed into mummified aphids, and 38.1 ± 13.2% of non-host-fed aphids died from other parasitoid-induced causes. However, the host feeding rate was reduced to only 1.2 ± 0.8%, and no significant parasitization mortality was observed on strawberry plants, suggesting that host plants interfered with A. abdominalis activity. This parasitoid does not, therefore, seem to be suited to either inoculative or inundative biocontrol of shallot aphids in strawberry. The three predators studied were the green lacewing, Chrysoperla carnea Steph. (Neuroptera: Chrysopidae), the two-spotted lady beetle, Adalia bipunctata L. (Coleoptera: Coccinellidae), and the gall midge Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae). Third instars of all 3 predators readily preyed upon the shallot aphid in Petri dish set-ups with significant differences in daily

  6. The ethylene response factor Pti5 contributes to potato aphid resistance in tomato independent of ethylene signalling.

    Science.gov (United States)

    Wu, Chengjun; Avila, Carlos A; Goggin, Fiona L

    2015-02-01

    Ethylene response factors (ERFs) comprise a large family of transcription factors that regulate numerous biological processes including growth, development, and response to environmental stresses. Here, we report that Pti5, an ERF in tomato [Solanum lycopersicum (Linnaeus)] was transcriptionally upregulated in response to the potato aphid Macrosiphum euphorbiae (Thomas), and contributed to plant defences that limited the population growth of this phloem-feeding insect. Virus-induced gene silencing of Pti5 enhanced aphid population growth on tomato, both on an aphid-susceptible cultivar and on a near-isogenic genotype that carried the Mi-1.2 resistance (R) gene. These results indicate that Pti5 contributes to basal resistance in susceptible plants and also can synergize with other R gene-mediated defences to limit aphid survival and reproduction. Although Pti5 contains the ERF motif, induction of this gene by aphids was independent of ethylene, since the ACC deaminase (ACD) transgene, which inhibits ethylene synthesis, did not diminish the responsiveness of Pti5 to aphid infestation. Furthermore, experiments with inhibitors of ethylene synthesis revealed that Pti5 and ethylene have distinctly different roles in plant responses to aphids. Whereas Pti5 contributed to antibiotic plant defences that limited aphid survival and reproduction on both resistant (Mi-1.2+) and susceptible (Mi-1.2-) genotypes, ethylene signalling promoted aphid infestation on susceptible plants but contributed to antixenotic defences that deterred the early stages of aphid host selection on resistant plants. These findings suggest that the antixenotic defences that inhibit aphid settling and the antibiotic defences that depress fecundity and promote mortality are regulated through different signalling pathways. PMID:25504643

  7. The influence of virus-induced changes in plants on aphid vectors: insights from luteovirus pathosystems.

    Science.gov (United States)

    Bosque-Pérez, Nilsa A; Eigenbrode, Sanford D

    2011-08-01

    Plant virus infection can alter the suitability of host plants for their aphid vectors. Most reports indicate that virus-infected plants are superior hosts for vectors compared to virus-free plants with respect to vector growth rates, fecundity and longevity. Some aphid vectors respond preferentially to virus-infected plants compared to virus-free ones, while others avoid infected plants that are inferior hosts. Thus, it appears vectors can exploit changes in host plant quality associated with viral infection. Enhanced vector performance and preference for virus-infected plants might also be advantageous for viruses by promoting their spread and possibly enhancing their fitness. Our research has focused on two of the most important luteoviruses that infect wheat (Barley yellow dwarf virus), or potato (Potato leafroll virus), and their respective aphid vectors, the bird-cherry oat aphid, Rhopalosiphum padi, and the green peach aphid, Myzus persicae. The work has demonstrated that virus infection of host plants enhances the life history of vectors. Additionally, it has shown that virus infection alters the concentration and relative composition of volatile organic compounds in host plants, that apterae of each vector species settle preferentially on virus-infected plants, and that such responses are mediated by volatile organic compounds. The findings also indicate that plants respond heterogeneously to viral infection and as a result different plant parts change in attractiveness to vectors during infection and vector responses to virus-infected plants are dynamic. Such dynamic responses could enhance or reduce the probability of virus acquisition by individual aphids searching among plants. Finally, our work indicates that compared to non-viruliferous aphids, viruliferous ones are less or not responsive to virus-induced host plant volatiles. Changes in vector responsiveness to plants after vectors acquire virus could impact virus epidemiology by influencing virus

  8. Seasonal phenology and species composition of the aphid fauna in a northern crop production area.

    Directory of Open Access Journals (Sweden)

    Sascha M Kirchner

    Full Text Available BACKGROUND: The species diversity of aphids and seasonal timing of their flight activity can have significant impacts on crop production, as aphid species differ in their ability to transmit plant viruses and flight timing affects virus epidemiology. The aim of the study was to characterise the species composition and phenology of aphid fauna in Finland in one of the northernmost intensive crop production areas of the world (latitude 64°. METHODOLOGY/PRINCIPAL FINDINGS: Flight activity was monitored in four growing seasons (2007-010 using yellow pan traps (YPTs placed in 4-8 seed potato fields and a Rothamsted suction trap. A total of 58,528 winged aphids were obtained, identified to 83 taxa based on morphology, and 34 species were additionally characterised by DNA barcoding. Seasonal flight activity patterns analysed based on YPT catch fell into three main phenology clusters. Monoecious taxa showed early or middle-season flight activity and belonged to species living on shrubs/trees or herbaceous plants, respectively. Heteroecious taxa occurred over the entire potato growing season (ca. 90 days. Abundance of aphids followed a clear 3-year cycle based on suction trap data covering a decade. Rhopalosiphum padi occurring at the end of the potato growing season was the most abundant species. The flight activity of Aphis fabae, the main vector of Potato virus Y in the region, and Aphis gossypii peaked in the beginning of potato growing season. CONCLUSIONS/SIGNIFICANCE: Detailed information was obtained on phenology of a large number aphid species, of which many are agriculturally important pests acting as vectors of plant viruses. Aphis gossypii is known as a pest in greenhouses, but our study shows that it occurs also in the field, even far in the north. The novel information on aphid phenology and ecology has wide implications for prospective pest management, particularly in light of climate change.

  9. [Obtainment of transgenic wheat with the insecticidal lectin from snowdrop (Galanthus nivalis agglutinin; GNA) gene and analysis of resistance to aphid].

    Science.gov (United States)

    Liang, Hui; Zhu, Yin-Feng; Zhu, Zhen; Sun, Dong-Fa; Jia, Xu

    2004-02-01

    Snowdrop lectin (Galanthus nivalis agglutinin; GNA) is toxic to sap sucking injurious insects of Homopteran. A new gna gene has been transferred into common spring wheat Zhong60634 and winter wheat Yumai66 with high yield by using the biolistic transformation method. Transgenic wheat plants have been obtained in both of the two varieties. Two transgenic plants (T0) have been obtained from the bombarded 535 immature embryos of Zhong60634. Bioassay results show that the development of aphid could be slowed down and the survival rate of young aphid could be reduced by gna gene. Seventeen transgenic plants (T0) were obtained from the bombarded 4636 immature embryos of Yumai66. Twenty plantlets with good resistance to Rhopalosiphum padi and Macrosiphum avenae, which are mainly aphid in north wheat area, were identified from the transgenic plants of T1 generation that came from 8 T0 transgenic plants with good resistance to aphid. The anti-aphid bioassay shows that resistance to the different grain aphid is not the same in transgenic wheat plants. To Rhopalosiphum padi, the rate of survival aphid 8 days after exposing transgenic plants to aphids is significantly lower than that of nontransgenic plants. To Macrosiphum avenae, growth speed of aphids is slowed down but not killed. At the same time, the death rate of young aphids is increased. Anyway, feeding of the two kinds of aphids has been controlled in a certain degree by gna gene when aphids can free to move in plants.

  10. Weed host specificity of the aphid, Aphis spiraecola: developmental and reproductive performance of aphids in relation to plant growth and leaf chemicals of the Siam weed, Chromolaena odorata.

    Science.gov (United States)

    Agarwala, B K; Das, Jhuma

    2012-01-01

    Density, distribution, and nutritional quality of plants are the causal basis of host plant selection in aphids. Nutritional qualities of a plant vary according to its growth stage and also in response to seasonal variation. How host plant growth stages shape aphid performance was studied in Aphis spiraecola Patch (Homoptera: Aphididae) on the perennial Siam weed, Chromolaena odorata (L.) King and Robinson (Asterales: Asteraceae). This plant species is the preferred host in the hot and humid tropical parts of northeast and southern India. Variations in developmental and reproductive performances in apterous viviparous female aphids were recorded in relation to differences in leaf chemicals in different growth stages of C. odorata. Aphids reproduced at higher rates in the vegetative stage of C. odorata when developmental time was shortest, and fecundity was higher in a longer reproductive time. Intrinsic rate of increase and net reproductive rate were also recorded to be higher in the vegetative stage of the weed host. In the vegetative stage, leaves contained higher quantity of proteins and nitrogen, which are vital for insect reproduction. Results of this study have demonstrated that A spiraecola showed synchronization of its developmental and reproductive performances to growth stages of C. odorata, which occur in high abundance in the study area. PMID:22950746

  11. Potential exposure of a classical biological control agent of the soybean aphid, Aphis glycines, on non-target aphids in North America

    Science.gov (United States)

    In summer 2007, the Asian parasitoid Binodoxys communis (Hymenoptera: Braconidae) was released in North America for control of the exotic soybean aphid, Aphis glycines (Homoptera: Aphididae). Despite its comparatively narrow host range, releases of B. communis may still constitute a risk to native a...

  12. Survival to parasitoids in an insect hosting defensive symbionts: a multivariate approach to polymorphic traits affecting host use by its natural enemy.

    Directory of Open Access Journals (Sweden)

    Emilie Bilodeau

    Full Text Available Insect parasitoids and their insect hosts represent a wide range of parasitic trophic relations that can be used to understand the evolution of biotic diversity on earth. Testing theories of coevolution between hosts and parasites is based on factors directly involved in host susceptibility and parasitoid virulence. We used controlled encounters with potential hosts of the Aphidius ervi wasp to elucidate behavioral and other phenotypic traits of host Acyrthosiphon pisum that most contribute to success or failure of parasitism. The host aphid is at an advanced stage of specialization on different crop plants, and exhibits intra-population polymorphism for traits of parasitoid avoidance and resistance based on clonal variation of color morph and anti-parasitoid bacterial symbionts. Randomly selected aphid clones from alfalfa and clover were matched in 5 minute encounters with wasps of two parasitoid lineages deriving from hosts of each plant biotype in a replicated transplant experimental design. In addition to crop plant affiliation (alfalfa, clover, aphid clones were characterized for color morph (green, pink, Hamiltonella defensa and Regiella insecticola symbionts, and frequently used behaviors in encounters with A. ervi wasps. A total of 12 explanatory variables were examined using redundancy analysis (RDA to predict host survival or failure to A. ervi parasitism. Aphid color was the best univariate predictor, but was poorly predictive in the RDA model. In contrast, aphid host plant and symbionts were not significant univariate predictors, but significant predictors in the multivariate model. Aphid susceptibility to wasp acceptance as reflected in host attacks and oviposition clearly differed from its suitability to parasitism and progeny development. Parasitoid progeny were three times more likely to survive on clover than alfalfa host aphids, which was compensated by behaviorally adjusting eggs invested per host. Strong variation of the

  13. Population fluctuation and faunal indices of aphids (Hemiptera, Aphididae) in peach orchards in Araucária, PR.

    Science.gov (United States)

    Schuber, J M; Monteiro, L B; Poltronieri, A S; Carvalho, R C Z; Zawadneak, M A C

    2009-08-01

    Aphids are sap-sucking insects that mainly attack shoots and young leaves of peach trees and many other plant species; however, knowledge of the Brazilian aphid fauna is scant. The objective of this study was to identify aphid species collected in peach orchards (Prunus persica Batsch) and to determine their faunal indices for occurrence and dominance. The experiment was conducted from July 2005 to September 2006 in six Chimarrita peach orchards in the municipality of Araucária, PR, Brazil. The survey of aphid species was conducted by visual samplings on peach trees and using Möericke-type yellow traps containing water. A faunal analysis was made using aphid occurrence and dominance indices. Brachycaudus persicae (Passerini, 1860) was the only aphid species that was found colonizing peach in Araucária/PR. Although most aphids collected were classified as rare, some can be considered potential peach colonizers, such as Myzus persicae (Sulzer, 1776) which was given the status of common or intermediate in some of the orchards studied. The population fluctuation of aphids showed a negative correlation with rainfall and positive correlation with temperature and relative humidity. PMID:19802456

  14. Biological control of cotton aphid (Aphis gossypii Glover) in cotton (inter)cropping systems in China; a simulation study.

    NARCIS (Netherlands)

    Xia, J.

    1997-01-01

    Cotton aphid ( Aphis gossypii Glover) is the key insect pest of seedling cotton ( Gossypium hirsutum L. ) in China, particularly in the North China cotton region. The resulting annual losses amount to 10-15% of the attainable yield. Sole reliance on insecticides against the cotton aphid in the past

  15. Using multispectral imagery to compare the spatial pattern of injury to wheat caused by Russian wheat aphid and greenbug

    Science.gov (United States)

    The Russian wheat aphid, Diuraphis noxia (Mordvilko), and greenbug, Schizaphis graminum (Rondani), are important aphid pests of wheat. Outbreaks of both pests in commercial wheat fields occur almost every year in the Great Plains of the United States. Infestations of both pests in wheat fields are...

  16. Peripheral odour perception by adult aphid forms with the same genotype but different host-plant preferences

    NARCIS (Netherlands)

    Hardie, J.; Visser, J.H.; Piron, P.G.M.

    1995-01-01

    As adults, the summer (alate virginopara) and autumn (gynopara) winged forms of the black bean aphid, Aphis fabae, utilise different host plants, the bean Vicia faba, and the spindle tree, Euonymus europaeus, respectively. Electroantennograms (EAGs) were recorded from the antennae of these aphid for

  17. Coupling genetics and proteomics to identify aphid proteins associated with vector-specific transmission of Polerovirus (Luteoviridae)

    Science.gov (United States)

    Cereal yellow dwarf virus-RPV (CYDV-RPV) is transmitted specifically by the aphids Rhopalosiphum padi and Schizaphis graminum in a circulative nonpropagative manner. The high level of vector-specificity results from the vector aphids having the functional components of the receptor-mediated endocyto...

  18. Predation determines different selective pressure on pea aphid host races in a complex agricultural mosaic.

    Directory of Open Access Journals (Sweden)

    Adalbert Balog

    Full Text Available Field assessments were conducted to examine the interplay between host plant and predation in complex agricultural mosaic on pea aphid clover and alfalfa races. In one experiment, we examined the relative fitness on clover race (CR and alfalfa race (AR pea aphids on broad bean, red clover and alfalfa alone. But because clover is typically grown in a more complex agricultural mosaic with alfalfa and broad bean, a second experiment was conducted to assess the fitness consequences under predation in a more complex agricultural field setting that also included potential apparent competition with AR pea aphids. In a third experiment we tested for the effect of differential host race density on the fitness of the other host race mediated by a predator effect. CR pea aphids always had fitness losses when on broad bean (had lower fitness on broad bean relative to red clover and fitness benefits when on red clover (higher fitness on red clover relative to broad bean, whether or not in apparent competition with alfalfa race aphids on bean and alfalfa. AR suffered fitness loss on both alfalfa and bean in apparent competition with CR on clover. Therefore we can conclude that the predation rate between host races was highly asymmetrical. The complexity of the agricultural mosaic thus can influence prey selection by predators on different host plants. These may have evolutionary consequences through context dependent fitness benefits on particular host plants.

  19. Distribution, host plants and natural enemies of sugar beet root aphid (Pemphigus fuscicornis In Slovakia

    Directory of Open Access Journals (Sweden)

    Tóth Peter

    2006-01-01

    Full Text Available During 2003-2004, field surveys were realized to observe the distribution of sugar beet aphid, Pemphigus fuscicornis (K o c h (Sternorrhyncha Pemphigidae in southwestern Slovakia. The research was carried out at 60 different localities with altitudes 112-220 m a. s. l. Sugar beet root aphid was recorded at 30 localities. The aphid was recorded in Slovakia for the first time, but its occurrence was predicted and symptoms and harmfulness overlooked by now. The presence of P. fuscicornis was investigated on roots of various plants from Chenopodiaceae. The most important host plants were various species of lambsquarters (above all Chenopodium album. Furthermore sugar beet (Beta vulgaris provar. altissima, red beet (B. vulgaris provar. conditiva and oraches (Atriplex spp act as host plants. Infestation of sugar beet by P. fuscicornis never exceeded 5% at single locality in Slovakia. Dry and warm weather create presumptions for strong harmfulness. In Slovakia, Chenopodium album is a very important indicator of sugar beet aphid presence allowing evaluation of control requirements. During the study, the larvae of Thaumatomyia glabra (Diptera: Chloropidae were detected as important natural enemies of sugar beet aphid. The species occurred at each location evaluated.

  20. Volatiles from Plants Induced by Multiple Aphid Attacks Promote Conidial Performance of Lecanicillium lecanii.

    Science.gov (United States)

    Lin, Yongwen; Hussain, Mubasher; Avery, Pasco Bruce; Qasim, Muhammad; Fang, Dalin; Wang, Liande

    2016-01-01

    Herbivore-induced plant volatiles (HIPVs) are clues that help predatory insects search for food. The hypothesis that entomopathogenic fungi, which protect plants, benefit from the release of HIPVs was tested. The plant Arabidopsis thaliana was used as the source of HIPVs. The insect herbivore Lipaphis erysimi (Kaltenbach) was used as the inducer, and the fungal pathogen of the aphid Lecanicillium lecanii was exposed to HIPVs to test our hypothesis. When exposed to aphid-induced A. thaliana volatiles, the mortality of aphids pre-treated with a conidial suspension of L. lecanii, the conidial germination and the appressorial formation were significantly increased compared with the control. The decan-3-ol and 4-methylpentyl isothiocyanate that were detected in the headspace seemed to have positive and negative affection, respectively. Moreover, HIPVs generated from groups of eight aphids per plant promoted significantly increased conidial germination and appressorial formation compared with HIPVs from groups of one, two and four aphids per plant. Our results demonstrated that the pathogenicity of the entomopathogenic fungus L. lecanii was enhanced when exposed to HIPVs and that the HIPVs were affected by the number of insect herbivores that induced them. PMID:26999795

  1. Volatiles from Plants Induced by Multiple Aphid Attacks Promote Conidial Performance of Lecanicillium lecanii.

    Directory of Open Access Journals (Sweden)

    Yongwen Lin

    Full Text Available Herbivore-induced plant volatiles (HIPVs are clues that help predatory insects search for food. The hypothesis that entomopathogenic fungi, which protect plants, benefit from the release of HIPVs was tested. The plant Arabidopsis thaliana was used as the source of HIPVs. The insect herbivore Lipaphis erysimi (Kaltenbach was used as the inducer, and the fungal pathogen of the aphid Lecanicillium lecanii was exposed to HIPVs to test our hypothesis. When exposed to aphid-induced A. thaliana volatiles, the mortality of aphids pre-treated with a conidial suspension of L. lecanii, the conidial germination and the appressorial formation were significantly increased compared with the control. The decan-3-ol and 4-methylpentyl isothiocyanate that were detected in the headspace seemed to have positive and negative affection, respectively. Moreover, HIPVs generated from groups of eight aphids per plant promoted significantly increased conidial germination and appressorial formation compared with HIPVs from groups of one, two and four aphids per plant. Our results demonstrated that the pathogenicity of the entomopathogenic fungus L. lecanii was enhanced when exposed to HIPVs and that the HIPVs were affected by the number of insect herbivores that induced them.

  2. Returns to integrated pest management research and outreach for soybean aphid.

    Science.gov (United States)

    Song, Feng; Swinton, Scott M

    2009-12-01

    Soybean aphid, Aphis glycines Matsumura, is a major invasive pest that has caused substantial yield loss and increased insecticide use in the United States since its discovery in 2000. Using the economic surplus approach, we estimate the economic benefits of U.S. research and outreach for integrated pest management (IPM) of soybean aphid. We calculate ex ante net benefits from adoption of an IPM economic threshold (ET). The ET triggers insecticide application only if the value of predicted yield damage from pest scouting is expected to exceed the cost of pest control. Our research finds that gradual adoption of an ET for soybean aphid management will generate a projected economic net benefit of $1.3 billion, for an internal rate of return of 124%, over the 15 yr since soybean aphid IPM research began in 2003. Lower and upper bound sensitivity analysis brackets the estimated net benefit to U.S. consumers and soybean, Glycine max (L.) Merr., growers in the range of $0.6 to $2.6 billion in 2005 dollars. If a 10% rate of return is attributed to IPM applied research and outreach on soybean aphid, that would leave nearly $800 million to compensate prior activities that contribute to the development and adoption of IPM.

  3. Annotated expressed sequence tags and xenobiotic detoxification in the aphid Myzus persicae (Sulzer)

    Institute of Scientific and Technical Information of China (English)

    C.C. FIGUEROA; N. PRUNIER-LETERME; C. RISPE; F. SEPULVEDA; E. FUENTES-CONTRERAS; B. SABATER-MUNOZ; J.-C. SIMON; D. TAGU

    2007-01-01

    Aphids (Hemiptera: Aphididae) are phytophagous insects that are importantagricultural pests. The enormous negative economic impacts caused by aphids worldwide arewell known, and are mostly due to their high multiplication rate and the transmission ofphytopathogenic viruses. Aphid management strategies mainly involve chemical treatmentswhich are pollutants and are increasingly inefficient, since aphids have developed multipleinsecticide-resistant mechanisms. Among the most economically important species is thegreen peach aphid Myzuspersicae Sulzer (Aphididae: Macrosiphini), which is able to colonizea wide range of host plants belonging to many different families, and transmits numerous plantviruses. Because of its large prevalence, M. persicae has been the target of massive insecticidetreatments; consequently, it has evolved several insecticide-resistant mechanisms. In thiswork, a collection of expressed genes from M. persicae is presented in order to identify putativegenes involved in xenobiotic detoxification. After cDNA cloning and sequencing, 959expressed sequence tags (EST) were annotated. Most sequences matched known genescorresponded to metabolism proteins (26%), ribosomal proteins (23%) and structural proteins(8%). Among them, several sequences corresponded to proteins putatively involved in sensing,degradation or detoxification of plant xenobiotic products.

  4. Photosynthesis and growth responses of pea Pisum sativum L. under heavy metals stress

    Institute of Scientific and Technical Information of China (English)

    Sabrine Hattab; Boutheina Dridi; Lassad Chouba; Mohamed Ben Kheder; Hamadi Bousetta

    2009-01-01

    The present work aims to study the physiological effects of cadmium (Cd) and copper (Cu) in pea (Pisum sativum).Pea plants were exposed to increasing doses of cadmium chloride (CdCl_2) and copper chloride (CuCl_2) for 20 d.The examined parameters,namely root and shoot lengths,the concentration of photosynthetic pigments and the rate of photosynthesis were affected by the treatments especially with high metals concentrations.The analysis of heavy metals accumulation shows that leaves significantly accumulate cadmium for all the tested concentrations.However,copper was significantly accumulated only with the highest tested dose.This may explain the higher inhibitory effects of cadmium on photosynthesis and growth in pea plants.These results are valuable for understanding the biological consequences of heavy metals contamination particularly in soils devoted to organic agriculture.

  5. Organic fertilization alters the community composition of root associated fungi in Pisum sativum

    DEFF Research Database (Denmark)

    Yu, L.; Nicolaisen, M.; Ravnskov, S.;

    2013-01-01

    Organic fertilization is well known to affect individual functional groups of root associated fungi such as arbuscular mycorrhizal (AM) fungi and root pathogens, but limited information is available on the effect of organic fertilization at the fungal community composition level. The main objecti......, the organic fertilizer Protamylasse clearly affects communities of root associated fungi, which seems to be linked to the life strategy of the different functional groups of root associated fungi. --------------------------------------------------------------------------------......Organic fertilization is well known to affect individual functional groups of root associated fungi such as arbuscular mycorrhizal (AM) fungi and root pathogens, but limited information is available on the effect of organic fertilization at the fungal community composition level. The main objective...... of the present study was to examine the response of communities of root associated fungi in Pisum sativum to Protamylasse, an organic fertilizer used in pea production. Plants were grown in pots with field soil amended with four different levels of Protamylasse. 454 pyrosequencing was employed to examine...

  6. Comparative phloem Mobility of nickel in nonsenescent plants. [Pisum sativa L. ; Pelargonium zonale L

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, P.M.; Chamel, A.

    1986-06-01

    /sup 63/Ni was applied to nonsenescent source leaves and found to be transported to sink tissues in pea (Pisum saativum L.) and geranium plants (Pelargonium zonale L.). The comparative mobilities (percent tracer transported out of source leaf division % /sup 86/Rb transported) for /sup 63/Ni in peas was 2.12 and in geranium 0.25. The value for the phloem mobile /sup 86/Rb was 1.00. By contrast, the comparative mobility of /sup 45/Ca, which is relatively immobile in the phloem, was low (0.05 in peas, 0.00 in geranium). Interruption of the phloem pathway between source and sink leaves by steam girdling almost completely inhibited /sup 63/Ni accumulation in the sink leaves of both species. The authors conclude that Ni is transported from nonsenescent source leaves to sink tissues via the phloem of leguminous and nonleguminous plants.

  7. Removal of chromium (III) and zinc(II) by using pods of pisum sativum (garden peas)

    International Nuclear Information System (INIS)

    The adsorption of Chromium(III) and Zinc(II) on ground pods of Pisum sativum (Garden peas) have been studied. The effects of adsorbent dose, pH, contact time and agitation speed on adsorption were studied. The study has revealed that pea pods have high metal removal efficiency. Cr(III) has been removed up to 80.92% and Zn(II) up to 75.11%. Adsorption equilibriums for both metals were developed, which were well described by the Langmuir and Freundlich isotherms. The maximum amounts of Cr(III) and Zn(II) adsorbed (Qmax), as evaluated by Langmuir isotherms were 1.88 mg and 1.45 mg per gram of pea pod's powder, respectively. It is anticipated that waste materials like pea pods can be used for removal of toxic metals like Cr(III) and Zn(II) from industrial effluents/waste waters. (author)

  8. Nitrogen deficiency hinders etioplast development in stems of dark-grown pea (Pisum sativum) shoot cultures.

    Science.gov (United States)

    Kósa, Annamária; Preininger, Éva; Böddi, Béla

    2015-11-01

    The effects of nitrogen (N) deprivation were studied in etiolated pea plants (Pisum sativum cv. Zsuzsi) grown in shoot cultures. The average shoot lengths decreased and the stems significantly altered considering their pigment contents, 77 K fluorescence spectra and ultrastructural properties. The protochlorophyllide (Pchlide) content and the relative contribution of the 654-655 nm emitting flash-photoactive Pchlide form significantly decreased. The etioplast inner membrane structure characteristically changed: N deprivation correlated with a decrease in the size and number of prolamellar bodies (PLBs). These results show that N deficiency directly hinders the pigment production, as well as the synthesis of other etioplast inner membrane components in etiolated pea stems.

  9. SSR genetic linkage map construction of pea(Pisum sativum L.) based on Chinese native varieties

    Institute of Scientific and Technical Information of China (English)

    Xuelian; Sun; Tao; Yang; Junjie; Hao; Xiaoyan; Zhang; Rebecca; Ford; Junye; Jiang; Fang; Wang; Jianping; Guan; Xuxiao; Zong

    2014-01-01

    Simple sequence repeat(SSR)markers have previously been applied to linkage mapping of the pea(Pisum sativum L.)genome.However,the transferability of existing loci to the molecularly distinct Chinese winter pea gene pool was limited.A novel set of pea SSR markers was accordingly developed.Together with existing SSR sequences,the genome of the G0003973(winter hardy)×G0005527(cold sensitive)cross was mapped using 190 F2individuals.In total,157 SSR markers were placed in 11 linkage groups with an average interval of 9.7 cM and total coverage of 1518 cM.The novel markers and genetic linkage map will be useful for marker-assisted pea breeding.

  10. Sources of reducing equivalents for nitrite reductase in Pisum arvense roots

    Directory of Open Access Journals (Sweden)

    Grażyna Kłobus

    2014-02-01

    Full Text Available Glucose-6-phosphate and NADP+ as well as malic acid and NADP+ present in the incubation mixture enhanced nitrite reductase (EC 1.6.6.4 activity in Pisum arvense roots. This was manifested by a depression of the nitrite level in the tissues and an increased reduction of nitrites by plastids isolated from P. arvense roots. A marked stimulation of plastid malate dehydrogenase was also observed under the influence of nitrates present in the medium. These results suggest that pyridin nucleotides utilised by NiR during nitrite reduction may be formed not only in processes of glucose-6-phosphate oxidation in the pentosephosphate cycle, but also of malic acid by NADP+-dependent malate dehydrogenase.

  11. Epigenetic Histone Marks of Extended Meta-Polycentric Centromeres of Lathyrus and Pisum Chromosomes.

    Science.gov (United States)

    Neumann, Pavel; Schubert, Veit; Fuková, Iva; Manning, Jasper E; Houben, Andreas; Macas, Jiří

    2016-01-01

    Species of the legume genera Lathyrus and Pisum possess chromosomes that exhibit a unique structure of their centromeric regions, which is clearly apparent during metaphase by the formation of extended primary constrictions which span up to a third of the length of the chromosome. In addition, these species express two different variants of the CenH3 protein which are co-localized in multiple domains along the poleward surface of the primary constrictions. Here, we show that the constrictions represent a distinct type of chromatin differing from the chromosome arms. In metaphase, histone phosphorylation patterns including H3S10ph, H3S28ph, and H3T3ph were observed along the entire constriction, in a way similar to holocentric chromosomes. On the other hand, distribution of phosphorylated H2AT120 was different from that previously reported from either, holocentric and monocentric chromosomes, occurring at chromatin surrounding but not overlapping CenH3 domains. Since some of these phosphorylations play a role in chromatid cohesion, it can be assumed that they facilitate correct chromosome segregation by ensuring that multiple separate CenH3 domains present on the same chromatid are oriented toward the same pole. The constrictions also displayed distinct patterns of histone methylation marks, being enriched in H3K9me2 and depleted in H3K4me3 and H3K27me2 compared to the chromosome arms. Super-resolution fluorescence microscopy revealed that although both CenH3 protein variants are present in all CenH3 domains detected on metaphase chromosomes, they are only partially co-localized while there are chromatin subdomains which are mostly made of only one CenH3 variant. Taken together, these data revealed specific features of extended primary constrictions of Lathyrus and Pisum and support the idea that they may represent an intermediate stage between monocentric and holocentric chromosomes. PMID:26973677

  12. Epigenetic histone marks of extended meta-polycentric centromeres of Lathyrus and Pisum chromosomes

    Directory of Open Access Journals (Sweden)

    Pavel eNeumann

    2016-03-01

    Full Text Available Species of the legume genera Lathyrus and Pisum possess chromosomes that exhibit a unique structure of their centromeric regions, which is clearly apparent during metaphase by the formation of extended primary constrictions which span up to a third of the length of the chromosome. In addition, these species express two different variants of the CenH3 protein which are co-localized in multiple domains along the poleward surface of the primary constrictions. Here we show that the constrictions represent a distinct type of chromatin differing from the chromosome arms. In metaphase, histone phosphorylation patterns including H3S10ph, H3S28ph and H3T3ph were observed along the entire constriction, in a way similar to holocentric chromosomes. On the other hand, distribution of phosphorylated H2AT120 was different from that previously reported from either, holocentric and monocentric chromosomes, occurring at chromatin surrounding but not overlapping CenH3 domains. Since some of these phosphorylations play a role in chromatid cohesion, it can be assumed that they facilitate correct chromosome segregation by ensuring that multiple separate CenH3 domains present on the same chromatid are oriented towards the same pole. The constrictions also displayed distinct patterns of histone methylation marks, being enriched in H3K9me2 and depleted in H3K4me3 and H3K27me2 compared to the chromosome arms. High resolution fluorescence microscopy revealed that although both CenH3 protein variants are present in all CenH3 domains detected on metaphase chromosomes, they are only partially co-localized while there are chromatin subdomains which are mostly made of only one CenH3 variant. Taken together, these data revealed specific features of extended primary constrictions of Lathyrus and Pisum and support the idea that they may represent an intermediate stage between monocentric and holocentric chromosomes.

  13. Laboratory and semi-field evaluation of Beauveria bassiana (Ascomycota: Hypocreales) against the lettuce aphid, Nasonovia ribisnigri (Hemiptera: Aphididae)

    DEFF Research Database (Denmark)

    Shrestha, Govinda; Enkegaard, Annie; Steenberg, Tove

    2015-01-01

    The lettuce aphid, Nasonovia ribisnigri (Mosley), is an economically important pest of lettuce worldwide. The entomopathogenic fungus Beauveria bassiana strain GHA has recently been reported as a potential biocontrol candidate for use against the lettuce aphid. This study provides information...... on the mortality inflicted by B. bassiana when applied against different life stages of the lettuce aphid under laboratory conditions and how fungus infection affects the aphid fecundity. In addition, temporal changes in persistence of fungus inoculum applied to foliage of young lettuce plants under semi......-field conditions was analysed. Immature life stages were generally the least susceptible to fungal infection and the susceptibility of all stages was dose-dependent, with the highest mortality occurring at the highest dose. B. bassiana significantly affected the rate of nymph production by the lettuce aphid...

  14. Identification of top-down forces regulating cotton aphid population growth in transgenic Bt cotton in central China.

    Directory of Open Access Journals (Sweden)

    Peng Han

    Full Text Available The cotton aphid Aphis gossypii Glover is the main aphid pest in cotton fields in the Yangtze River Valley Cotton-planting Zone (YRZ in central China. Various natural enemies may attack the cotton aphid in Bt cotton fields but no studies have identified potential specific top-down forces that could help manage this pest in the YRZ in China. In order to identify possibilities for managing the cotton aphid, we monitored cotton aphid population dynamics and identified the effect of natural enemies on cotton aphid population growth using various exclusion cages in transgenic Cry1Ac (Bt+CpTI (Cowpea trypsin inhibitor cotton field in 2011. The aphid population growth in the open field (control was significantly lower than those protected or restricted from exposure to natural enemies in the various exclusion cage types tested. The ladybird predator Propylaea japonica Thunberg represented 65% of Coccinellidae predators, and other predators consisted mainly of syrphids (2.1% and spiders (1.5%. The aphid parasitoids Aphidiines represented 76.7% of the total count of the natural enemy guild (mainly Lysiphlebia japonica Ashmead and Binodoxys indicus Subba Rao & Sharma. Our results showed that P. japonica can effectively delay the establishment and subsequent population growth of aphids during the cotton growing season. Aphidiines could also reduce aphid density although their impact may be shadowed by the presence of coccinellids in the open field (likely both owing to resource competition and intraguild predation. The implications of these results are discussed in a framework of the compatibility of transgenic crops and top-down forces exerted by natural enemy guild.

  15. Changes in monoterpene emission rates of Quercus ilex infested by aphids tended by native or invasive Lasius ant species.

    Science.gov (United States)

    Paris, Carolina I; Llusia, Joan; Peñuelas, Josep

    2010-07-01

    The emission of volatile organic compounds (VOCs) depends on temperature and light. Other factors such as insect herbivory also may modify VOC emission. In particular, aphid feeding promotes the release of new compounds and changes the composition of plant volatile blends. Given that some aphids are tended by ants, we investigated whether ants change the emission of VOCs indirectly through attendance on aphids. The effect of Lachnus roboris aphids and two different tending ant species on terpene emission rates of 4-year-old holm oak (Quercus ilex) saplings was investigated during a field experiment. There were five treatments: saplings alone (T1), saplings infested with L. roboris aphids (T2), saplings infested with aphids tended by the local ant Lasius grandis (T3), those tended by small colonies of the invasive ant Lasius neglectus (T4), and those tended by large colonies of the same invasive ant species (T5). The infestation by L. roboris elicited the emission of Delta(3)-carene and increased the emission of myrcene and gamma-terpinene. Terpene emissions were modified depending on the tending ant species. Attendance by the local ant L. grandis increased alpha and beta-pinene and sabinene. Attendance by the invasive ant L. neglectus only decreased significantly the emission of myrcene, one of the major compounds of the Q. ilex blend. Aphid abundance decreased with time for all treatments, but there was no difference in aphid abundance among treatments. Total terpene emission rates were not correlated with aphid abundance. These results highlight that aphids and tending ants may change terpene emission rates, depending on the ant species. PMID:20549328

  16. Wheat Nitrogen Fertilisation Effects on the Performance of the Cereal Aphid Metopolophium dirhodum

    Directory of Open Access Journals (Sweden)

    Alan F. J. Gash

    2012-02-01

    Full Text Available The effects of five rates of nitrogen fertiliser applications on the performance of the cereal aphid Metopolophium dirhodum on winter wheat, within the range of rates recommended for UK crops, were investigated over two seasons in field-grown crops and also on plants grown in the glasshouse. Longevity was unaffected by the level of fertilisation, but aphid intrinsic rate of increase and fecundity increased with each level applied. In the second field season, when a higher upper limit was used, many of these increases were significant. A previously unreported finding for this species was that there was a significant decrease in fecundity for the highest rate of fertilisation. Results for the glasshouse-reared aphids followed a similar pattern to those in the field, and overall they underline recent reports in the literature of the negative effects of high nutrient concentrations on the performance of herbivorous insects. The underlying reasons for these are discussed.

  17. EVALUATION OF DIFFERENT SYNTHETIC AND BOTANICAL INSECTICIDE AGAINST APHID, APHIS GOSSYPII GLOVER INFESTING ISABGOL CROP

    Directory of Open Access Journals (Sweden)

    B. R. PATEL

    2013-01-01

    Full Text Available An investigation was carried out during 2008-09 to evaluate the different insecticides against aphid, Aphisgossypii Glover infesting isabgol (Plantago ovata crop under field condition at Sardarkrushinagar, S. D. A. U.,Dantiwada. The result of the field study revealed that, among all the chemical and botanical insecticides used,carbosulfan @ 0.05 per cent was found to be most effective by recording lowest population of aphid as per aphidindexing method (0.99 A. I. with the highest seed yield, 11.24 q/ha and neem oil @ 0.5 per cent was superiorthan other botanical recording (1.83 A. I. with a maximum 7.21 q/ha seed yield. Thus, from the overall resultsit can be concluded that the carbosulfan @ 0.05 and neem oil 0.5 per cent proved most effective for themanagement of aphid A. gossypii in isabgol crop.

  18. Characterisation of aphid myrosinase and degradation studies of glucosinolates.

    Science.gov (United States)

    Francis, Frédéric; Lognay, Georges; Wathelet, Jean-Paul; Haubruge, Eric

    2002-08-01

    Myrosinase from Brevicoryne brassicae was purified by ammonium sulfate fractionation, dialysis, and chromatography on a DEAE column. The chromatography yielded a single peak and a 115.6-fold purification. Further FPLC gel filtration gave a single peak at 120 kDa. Denaturing SDS/PAGE of the protein revealed a single band at 60 kDa, indicating that the native B. brassicae myrosinase is a dimer. Kinetic parameters towards 8 glucosinolates were calculated. Strong differences of V(max) and K(m) were observed depending on the substrate. Degradation products of each glucosinolate were identified and quantified by GC-MS and GLC-FID, respectively. Using both crude aphid homogenates and purified myrosinase, two unique hydroxyglucosinolates, 3-butenyl- and benzyl-isothiocyanates were identified from progoitrin ((2S)-2-hydroxybut-3-enyl-glucosinolate) and sinalbin (4-hydroxybenzyl-glucosinolate) degradation respectively. Addition of ascorbic acid to the reaction mixtures containing sinalbin and progoitrin caused the production of hydroxylated degradation products usually associated with plant myrosinase metabolisation. The occurrence of the myrosinase system in B. brassicae is discussed in terms of similar allelochemical adaptation between the herbivore and its host plant. PMID:12125058

  19. Individual and population variation in invertebrates revealed by Inter-simple Sequence Repeats (ISSRs

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    Patrick Abbot

    2001-08-01

    Full Text Available PCR-based molecular markers are well suited for questions requiring large scale surveys of plant and animal populations. Inter-simple Sequence Repeats or ISSRs are analyzed by a recently developed technique based on the amplification of the regions between inverse-oriented microsatellite loci with oligonucleotides anchored in microsatellites themselves. ISSRs have shown much promise for the study of the population biology of plants, but have not yet been explored for similar studies of animals. The value of ISSRs is demonstrated for the study of animal species with low levels of within-population variation. Sets of primers are identified which reveal variation in two aphid species, Acyrthosiphon pisum and Pemphigus obesinymphae, in the yellow fever mosquito Aedes aegypti, and in a rotifer in the genus Philodina.

  20. Analysis of the Gut Microbes of the Chinese White Wax Scale Ericerus pela and Molecular Detection of Rickettsia%白蜡虫肠道微生物分析及立克次氏体分子检测

    Institute of Scientific and Technical Information of China (English)

    徐冬丽; 刘魏魏; 胡艳红; 杨璞; 陈晓鸣

    2012-01-01

    To understand the diversity of the gut microbes of Chinese white wax scale Ericerus pela, 16S rDNA clone library was constructed to analyze the gut microbes of the female E. pela adults. The results showed that, the gut of E. pela contained abundant of Rickettsia. Gut microbes Arsenophonus and Variovorax were also been identified. And Rickettsia was the main bacteria in gut of E. pela. The phylogenetic analysis of the 16S rDNA showed that, the Rickettsia from E. pela has close relationship with that of pea aphid Acyrthosiphon pisum. PCR amplification was performed using the specific primers for Rickettsia to detect infection in 30 male and 30 female individuals. The result showed that, the infected male and female were 24 and 12 respectively.

  1. Bad housekeeping: why do aphids leave their exuviae inside the colony?

    Directory of Open Access Journals (Sweden)

    Boivin Guy

    2008-12-01

    Full Text Available Abstract Background Animals can gain protection against predators and parasites by living in groups. The encounter-dilution effect provides protection when the probability of detection of a group does not increase in proportion to group size (i.e. encounter effect, so that predators do not offset the encounter effect by attacking more members of the group (i.e. dilution effect. In this paper, we propose a novel mechanism by which prey insects could gain by producing decoys that act as multiple targets for predators or parasitoids if these decoys are recognised as preys or hosts and negatively affect the patch foraging strategy of these predators and parasitoids. Such a decoy mechanism could be present in aphid colonies in which aphid exuviae are recognised and attacked by Aphidiine wasps. Results We conducted a behavioural study to evaluate the effect of exuviae on parasitoid patch residence time and egg allocation in experimental aphid patches with or without exuviae. We showed that exuviae are recognised and attacked at the same level as aphids when both are present in the patch. While parasitism rate was not significantly lower in patches with exuviae when the parasitoid left the patch, the time wasted by parasitoids to handle exuviae did influence the patch residence time. As a consequence, the attack rate on the live aphids was lower in patches that contain exuviae. Conclusion Aphids had more time available to flee and thus each individual might gain protection against parasitoids by leaving their exuviae near and within the colony. These results demonstrate that the encounter-dilution effect provided by living in a group can be enhanced by extra-materials that act as decoy for natural enemies.

  2. Genetic mapping shows intraspecific variation and transgressive segregation for caterpillar-induced aphid resistance in maize.

    Science.gov (United States)

    Tzin, Vered; Lindsay, Penelope L; Christensen, Shawn A; Meihls, Lisa N; Blue, Levi B; Jander, Georg

    2015-11-01

    Plants in nature have inducible defences that sometimes lead to targeted resistance against particular herbivores, but susceptibility to others. The metabolic diversity and genetic resources available for maize (Zea mays) make this a suitable system for a mechanistic study of within-species variation in such plant-mediated interactions between herbivores. Beet armyworms (Spodoptera exigua) and corn leaf aphids (Rhopalosiphum maidis) are two naturally occurring maize herbivores with different feeding habits. Whereas chewing herbivore-induced methylation of 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one glucoside (DIMBOA-Glc) to form 2-hydroxy-4,7-dimethoxy-1,4-benzoxazin-3-one glucoside (HDMBOA-Glc) promotes caterpillar resistance, lower DIMBOA-Glc levels favour aphid reproduction. Thus, caterpillar-induced DIMBOA-Glc methyltransferase activity in maize is predicted to promote aphid growth. To test this hypothesis, the impact of S. exigua feeding on R. maidis progeny production was assessed using seventeen genetically diverse maize inbred lines. Whereas aphid progeny production was increased by prior caterpillar feeding on lines B73, Ki11, Ki3 and Tx303, it decreased on lines Ky21, CML103, Mo18W and W22. Genetic mapping of this trait in a population of B73 × Ky21 recombinant inbred lines identified significant quantitative trait loci on maize chromosomes 1, 7 and 10. There is a transgressive segregation for aphid resistance, with the Ky21 alleles on chromosomes 1 and 7 and the B73 allele on chromosome 10 increasing aphid progeny production. The chromosome 1 QTL coincides with a cluster of three maize genes encoding benzoxazinoid O-methyltransferases that convert DIMBOA-Glc to HDMBOA-Glc. Gene expression studies and benzoxazinoid measurements indicate that S. exigua -induced responses in this pathway differentially affect R. maidis resistance in B73 and Ky21. PMID:26462033

  3. Natural enemies act faster than endophytic fungi in population control of cereal aphids.

    Science.gov (United States)

    Härri, Simone A; Krauss, Jochen; Müller, Christine B

    2008-05-01

    1. Fast-growing populations of phytophagous insects can be limited by the presence of natural enemies and by alkaloids that are produced by symbiotic associations of many temperate grass species with endophytic fungi. It is unclear if and how acquired plant defences derived from endophytic fungi interact with natural enemies to affect phytophagous insect populations. 2. To assess the relative importance of endophytic fungi compared to that of natural enemies on the population dynamics of phytophagous insects, we carried out a fully factorial field experiment, in which the presence of natural enemies and the presence of endophytic fungi were manipulated simultaneously. Target colonies of aphids were monitored for 8 weeks starting from their natural appearance in the field to the end of the aphid season. 3. We show that on Lolium perenne increased natural enemy densities reduced the individual numbers of two common cereal aphids, Rhopalosiphum padi and Metopolophium festucae. 4. The presence of the endophytic fungi Neotyphodium lolii reduced the number of M. festucae but did not affect the number of R. padi. The reduction in R. padi numbers by predators and parasitoids was not influenced by the presence of endophytes. For adult M. festucae, however, the negative effects of natural enemies were significant only in the absence of endophytes. 5. Over the duration of the experiment, the effect of natural enemies on aphid colony growth was much stronger than the effect of the endophytic fungi N. lolii, presumably because predator and parasitoid action on aphid colonies is much faster than any effects of endophytes. 6. Our results demonstrate that with simultaneous action of acquired endosymbionts and natural enemies, both factors can control aphid colony growth but they generally act independently of each other.

  4. Role of terpenes from aphid-infested potato on searching and oviposition behavior of Episyrphus balteatus

    Institute of Scientific and Technical Information of China (English)

    NICOLAS HARMEL; RAKI ALMOHAMAD; MARIE-LAURE FAUCONNIER; PATRICK DU JARDIN; FRANCO IS VERHEGGEN; MICHEL MARLIER; ERIC HAUBRUGE; FR(E)D(E)RIC FRANCIS

    2007-01-01

    To cope with pathogen and insect attacks, plants develop different mechanismsof defence, in both direct (physical and chemical) and indirect ways (attractive volatiles toentomophagous beneficials). Plants are then able to express traits that facilitate "top-down"control of pests by attracting herbivore predators. Here we investigate the indirect defencemechanism of potato plants by analyzing the volatile patterns of both healthy and aphidinfested plants. Important changes in the emitted terpene pattern by the Myzus persicaeinfested host plant were observed. Using Solid Phase MicroExtraction (SPME) and GC-MS,the (E)-β-farnesene (EBF) appeared to be emitted by aphid-infested potato and not byhealthy plants. To assess the infochemical role of these volatile releases after aphid damageon the aphidophagous predators Episyrphus balteatus, the hoverfly foraging behavior wasassessed using the Observer 5.0 software (Noldus, Wageningen, The Netherlands). Aphidfree potato plants were also used as a control volatile source in the predator behavioral study.While aphid-infested plants induced efficient searching and acceptation behaviors leadingto egg-laying, no kairomonal effect of healthy potato plants was observed, leading to longerimmobility durations and shorter searching periods in the net cage. High oviposition rate ofE. balteatus was observed when aphid-infested potato was used (mean of 48.9 eggs perlaying and per female). On the other hand, no egg was produced by the hoverfly on healthyaphid-free plants. The E. balteatus foraging and reproductive behaviors according to thevolatile emission from aphid-infested plants are discussed in relation to the potential use ofactive infochemical molecules in integrated aphid pest management.

  5. First record of the adventive oriental aphid Schizaphis piricola (Matsumura, 1917 (Hemiptera, Aphididae in Europe

    Directory of Open Access Journals (Sweden)

    Nicolás Pérez-Hidalgo

    2011-04-01

    Full Text Available The oriental aphid Schizaphis piricola Matsumura, is recorded for the first time in Europe, on the ornamental pear tree Pyrus calleryana in landscaped areas in Madrid (Spain. Data on the morphology of the primary host (apterous and alate fundatrigeniae and fundatrices, and their biology and distribution are given. The keys for identifying species of Schizaphis (Schizaphis in the Iberian Peninsula are updated. Two species of aphids are also recorded for the first time on Pyrus calleryana: S. piricola and Aphis pomi.

  6. New invasive species of aphids (Hemiptera, Aphididae in Serbia and Montenegro

    Directory of Open Access Journals (Sweden)

    Petrović-Obradović Olivera

    2010-01-01

    Full Text Available Three new invasive species of aphids have been found in Serbia: Chaitophorus populifolli Essig, Myzocallis walshii (Monell and Trichosiphonaphis polygonifoliae (Shinji and two have been found in Montenegro: Aphis illinoisensis Shimer and Tinocallis kahawaluokalani (Kirkaldy. A. illinoisensis is a pest of the grapevine, T. polygonifoliae, feeds on a decorative shrub (Lonicera and the other three feed on trees (Populus, Quercus and Lagerostroemia. Three of the species are American aphids and two are of Asian origin. Their morphology, illustrated by original drawings and data on the biology and distribution are given. .

  7. Comparative analysis of Solanum stoloniferum responses to probing by the green peach aphid Myzus persicae and the potato aphid Macrosiphum euphorbiae

    Institute of Scientific and Technical Information of China (English)

    Adriana E.Alvarez; Viviana G.Broglia; Anahí M.Alberti D'Amato; Doret Wouters; Edwin van der Vossen; Elisa Garzo; W.Fred Tjallingii

    2013-01-01

    Plants protect themselves against aphid attacks by species-specific defense mechanisms.Previously,we have shown that Solanum stoloniferum Schlechtd has resistance factors to Myzus persicae Sulzer (Homoptera:Aphididae) at the epidermal/mesophyll level that are not effective against Macrosiphum euphorbiae Thomas (Homoptera:Aphididae).Here,we compare the nymphal mortality,the pre-reproductive development time,and the probing behavior of M.persicae and M.euphorbiae on S.stoloniferum and Solanum tuberosum L.Furthermore,we analyze the changes in gene expression in S.stoloniferum 96 hours post infestation by either aphid species.Although the M.euphorbiae probing behavior shows that aphids encounter more probing constrains on phloem activities-longer probing and salivation time-on S.stoloniferum than on S.tuberosum,the aphids succeeded in reaching a sustained ingestion of phloem sap on both plants.Probing by M.persicae on S.stoloniferum plants resulted in limited feeding only.Survival of M.euphorbiae and M.persicae was affected on young leaves,but not on senescent leaves of S.stoloniferum.Infestation by M.euphorbiae changed the expression of more genes than M.persicae did.At the systemic level both aphids elicited a weak response.Infestation of S.stoloniferum plants with a large number ofM.persicae induced morphological changes in the leaves,leading to the development of pustules that were caused by disrupted vascular parenchyma and surrounding tissue.In contrast,an infestation by M.euphorbiae had no morphological effects.Both plant species can be regarded as good host for M.euphorbiae,whereas only S.tuberosum is a good host for Mo persicae and S.stoloniferum is not.Infestation of S.stoloniferum by M.persicae or M.euphorbiae changed the expression of a set of plant genes specific for each of the aphids as well as a set of common genes.

  8. Establishment of Lipolexis oregmae (Hymenoptera: Aphidiidae) in a classical biological control program directed against the brown citrus aphid (Homoptera: Aphididae) in Florida

    International Nuclear Information System (INIS)

    The parasitoid Lipolexis oregmae Gahan (introduced as L. scutellaris Mackauer) was imported from Guam, evaluated in quarantine, mass reared, and released into citrus groves in Florida in a classical biological control program directed against the brown citrus aphid, Toxoptera citricida Kirkaldy. Releases of 20,200, 12,100, and 1,260 adults of L. oregmae were made throughout Florida during 2000, 2001, and 2002, respectively. To determine if L. oregmae had successfully established, surveys were conducted throughout the state beginning in the summer of 2001 and continuing through the summer of 2003. Parasitism during 2001 and 2002 was evaluated by holding brown citrus aphids in the laboratory until parasitoid adults emerged. Lipolexis oregmae was found in 10 sites in 7 counties and 4 sites in 3 counties with parasitism rates ranging from 0.7 to 3.3% in 2001 and 2002, respectively. Laboratory tests indicated that high rates of mortality occurred if field-collected parasitized aphids were held in plastic bags, so a molecular assay was used that allowed immature L. oregmae to be detected within aphid hosts immediately after collection. The molecular assay was used in 2003 with the brown citrus aphids and with other aphid species collected from citrus, weeds, and vegetables near former release sites; immatures of L. oregmae were detected in black citrus aphids, cowpea aphids, spirea aphids, and melon aphids, as well as in the brown citrus aphid, in 4 of 8 counties sampled, with parasitism ranging from 2.0 to 12.9%, indicating that L. oregmae is established and widely distributed. Samples taken in Polk County during Oct 2005 indicated that L. oregmae has persisted. The ability of L. oregmae to parasitize other aphid species on citrus, and aphids on other host plants, enhances the ability of L. oregmae to persist when brown citrus aphid populations are low. (author)

  9. Prevalence, Development, and Significance of Ascochyta Blight Caused by Peyronellaea pinodes in Pisum elatius Populations Growing in Natural Ecosystems.

    Science.gov (United States)

    Golani, M; Frenkel, O; Bornstein, M; Shulhani, R; Abbo, S; Shtienberg, D

    2016-08-01

    Wild Pisum populations prevail in Israel in regions with diverse climatic conditions. A comprehensive survey was conducted in the winters of 2007-08 and 2008-09 at two sites in northern Israel, aiming to (i) document the density of Pisum elatius plants in natural ecosystems and elucidate factors related to their initial infection by Ascochyta blight and (ii) determine the factors governing disease development over time on individual plants. The surveyors identified P. elatius plants growing in designated quadrats, inspected each plant visually, and recorded the incidence and severity of its Ascochyta blight symptoms. Ascochyta blight, caused by Peyronellaea pinodes, was ubiquitous in Pisum elatius populations at both survey sites in both seasons. However, the total leaf area exhibiting disease symptoms of individual plants was very low, and stem and pod infections were rarely observed. Based on analyses of the survey data, it was suggested that, in natural ecosystems, the teleomorph stage of Peyronellaea pinodes serves as the main source of the primary and the secondary inoculum of the disease. In addition, it was found that infected leaves dropped off soon after infection, thereby precluding development of stem lesions. The plants continued growing and did not die; thus, they overcame the disease and could be considered "cured". This phenomenon was examined and confirmed in artificially inoculated, potted-plant experiments. It would be worthwhile to exploit the potential of this unique resistance mechanism as a tool for Ascochyta blight management in pea breeding. PMID:27050576

  10. Prevalence, Development, and Significance of Ascochyta Blight Caused by Peyronellaea pinodes in Pisum elatius Populations Growing in Natural Ecosystems.

    Science.gov (United States)

    Golani, M; Frenkel, O; Bornstein, M; Shulhani, R; Abbo, S; Shtienberg, D

    2016-08-01

    Wild Pisum populations prevail in Israel in regions with diverse climatic conditions. A comprehensive survey was conducted in the winters of 2007-08 and 2008-09 at two sites in northern Israel, aiming to (i) document the density of Pisum elatius plants in natural ecosystems and elucidate factors related to their initial infection by Ascochyta blight and (ii) determine the factors governing disease development over time on individual plants. The surveyors identified P. elatius plants growing in designated quadrats, inspected each plant visually, and recorded the incidence and severity of its Ascochyta blight symptoms. Ascochyta blight, caused by Peyronellaea pinodes, was ubiquitous in Pisum elatius populations at both survey sites in both seasons. However, the total leaf area exhibiting disease symptoms of individual plants was very low, and stem and pod infections were rarely observed. Based on analyses of the survey data, it was suggested that, in natural ecosystems, the teleomorph stage of Peyronellaea pinodes serves as the main source of the primary and the secondary inoculum of the disease. In addition, it was found that infected leaves dropped off soon after infection, thereby precluding development of stem lesions. The plants continued growing and did not die; thus, they overcame the disease and could be considered "cured". This phenomenon was examined and confirmed in artificially inoculated, potted-plant experiments. It would be worthwhile to exploit the potential of this unique resistance mechanism as a tool for Ascochyta blight management in pea breeding.

  11. Use of slow-release plant infochemicals to control aphids: a first investigation in a Belgian wheat field.

    Science.gov (United States)

    Zhou, Haibo; Chen, Longsheng; Liu, Yong; Chen, Julian; Francis, Frédéric

    2016-01-01

    Using infochemicals to develop a push-pull strategy in pest control is a potential way to promote sustainable crop production. Infochemicals from plant essential oils were mixed with paraffin oil for slow release in field experiments on wheat to control the population density of cereal aphids and to enhance their natural enemies. (Z)-3-Hexenol (Z3H) attracted Metopolophum dirhodum and Sitobion avenae, the predominant species on wheat in Belgium, and may be a useful infochemical for aphid control by attracting aphids away from field plots. Release of (E)-β-farnesene (EBF) or a garlic extract (GE) led to a significant decrease in the abundance of wheat aphids. The main natural enemies of cereal aphids found were lacewings (47.8%), hoverflies (39.4%), and ladybirds (12.8%). Ladybird abundance varied little before the end of the wheat-growing season. Our results suggest that these chemicals can form the basis of a "push-pull" strategy for aphid biological control, with GE and EBF acting as a pest- and beneficial-pulling stimulus and Z3H for aphid pulling. PMID:27530318

  12. Bacterial symbionts, Buchnera, and starvation on wing dimorphism in English grain aphid, Sitobion avenae (F. (Homoptera: Aphididae

    Directory of Open Access Journals (Sweden)

    Fangmei eZhang

    2015-05-01

    Full Text Available Wing dimorphism in aphids can be affected by multiple cues, including both biotic (nutrition, crowding, interspecific interactions, the presence of natural enemies, maternal and transgenerational effects, and alarm pheromone and abiotic factors (temperature, humidity, and photoperiod. The majority of the phloem-feeding aphids carry Buchnera, an obligate symbiotic proteobacteria. Buchnera has a highly reduced genome size, but encode key enzymes in the tryptophan biosynthetic pathway and is crucial for nutritional balance, development and reproduction in aphids. In this study, we investigated the impact of two nutritional-based biotic factors, symbionts and starvation, on the wing dimorphism in the English grain aphid, Sitobion avenae, a devastating insect pest of cereal crops (e.g., wheat worldwide. Elimination of Buchnera using the antibiotic rifampicin significantly reduced the formation of winged morphs, body mass and fecundity in S. avenae. Furthermore, the absence of this primary endosymbiont may disrupt the nutrient acquisition in aphids and alter transgenerational phenotypic expression. Similarly, both survival rate and the formation of winged morphs were substantially reduced after neonatal (< 24h old offspring were starved for a period of time. The combined results shed light on the impact of two nutritional-based biotic factors on the phenotypic plasticity in aphids. A better understanding of the wing dimorphism in aphids will provide the theoretical basis for the prediction and integrated management of these phloem-feeding insect pests.

  13. Sink-source interactions between a galling aphid and its narrowleaf cottonwood host: Within and between plant variation

    International Nuclear Information System (INIS)

    The authors examined within and between plant variation in the capacity of the leaf gallin aphid, Pemphigus betae, to manipulate the sink-source translocation patterns of its host, narrowleaf cottonwood (Populus angustifolia). Within a plant, a series of 14C-labeling experiments showed that P. betae actively manipulated host translocation patterns by acting as a strong sink and fed on assimilates produced in surrounding plant tissues serving as sources. Food resources drawn into the galled leaf from storage tissues in the stem and from surrounding leaves were a major resource for this herbivore in addition to resources from the galled leaf blade. Aphids compete for resources with natural plant sinks, such as developing fruits. In common gardens containing aphid resistant and aphid susceptible clones, I tested the hypothesis that aphid gall success on resistant trees is limited by competition between aphid-induced sinks and the plant's natural sinks, and that the intensity of intraplant competition was determined by the genetically determined architecture of the tree. Through bud removal, a resistant clone could be given the architecture of a susceptible clone. Aphid survival was increased two fold on architecturally modified resistant clones

  14. Use of slow-release plant infochemicals to control aphids: a first investigation in a Belgian wheat field.

    Science.gov (United States)

    Zhou, Haibo; Chen, Longsheng; Liu, Yong; Chen, Julian; Francis, Frédéric

    2016-08-17

    Using infochemicals to develop a push-pull strategy in pest control is a potential way to promote sustainable crop production. Infochemicals from plant essential oils were mixed with paraffin oil for slow release in field experiments on wheat to control the population density of cereal aphids and to enhance their natural enemies. (Z)-3-Hexenol (Z3H) attracted Metopolophum dirhodum and Sitobion avenae, the predominant species on wheat in Belgium, and may be a useful infochemical for aphid control by attracting aphids away from field plots. Release of (E)-β-farnesene (EBF) or a garlic extract (GE) led to a significant decrease in the abundance of wheat aphids. The main natural enemies of cereal aphids found were lacewings (47.8%), hoverflies (39.4%), and ladybirds (12.8%). Ladybird abundance varied little before the end of the wheat-growing season. Our results suggest that these chemicals can form the basis of a "push-pull" strategy for aphid biological control, with GE and EBF acting as a pest- and beneficial-pulling stimulus and Z3H for aphid pulling.

  15. Use of slow-release plant infochemicals to control aphids: a first investigation in a Belgian wheat field

    Science.gov (United States)

    Zhou, Haibo; Chen, Longsheng; Liu, Yong; Chen, Julian; Francis, Frédéric

    2016-01-01

    Using infochemicals to develop a push–pull strategy in pest control is a potential way to promote sustainable crop production. Infochemicals from plant essential oils were mixed with paraffin oil for slow release in field experiments on wheat to control the population density of cereal aphids and to enhance their natural enemies. (Z)-3-Hexenol (Z3H) attracted Metopolophum dirhodum and Sitobion avenae, the predominant species on wheat in Belgium, and may be a useful infochemical for aphid control by attracting aphids away from field plots. Release of (E)-β-farnesene (EBF) or a garlic extract (GE) led to a significant decrease in the abundance of wheat aphids. The main natural enemies of cereal aphids found were lacewings (47.8%), hoverflies (39.4%), and ladybirds (12.8%). Ladybird abundance varied little before the end of the wheat-growing season. Our results suggest that these chemicals can form the basis of a “push–pull” strategy for aphid biological control, with GE and EBF acting as a pest- and beneficial-pulling stimulus and Z3H for aphid pulling. PMID:27530318

  16. Evidence for an invasive aphid "superclone": extremely low genetic diversity in Oleander aphid (Aphis nerii populations in the southern United States.

    Directory of Open Access Journals (Sweden)

    John Scott Harrison

    Full Text Available BACKGROUND: The importance of genetic diversity in successful biological invasions is unclear. In animals, but not necessarily plants, increased genetic diversity is generally associated with successful colonization and establishment of novel habitats. The Oleander aphid, Aphis nerii, though native to the Mediterranean region, is an invasive pest species throughout much of the world. Feeding primarily on Oleander (Nerium oleander and Milkweed (Asclepias spp. under natural conditions, these plants are unlikely to support aphid populations year round in the southern US. The objective of this study was to describe the genetic variation within and among US populations of A. nerii, during extinction/recolonization events, to better understand the population ecology of this invasive species. METHODOLOGY/PRINCIPAL FINDINGS: We used five microsatellite markers to assess genetic diversity over a two year period within and among three aphid populations separated by small (100 km and large (3,700 km geographic distances on two host plant species. Here we provide evidence for A. nerii "superclones". Genotypic variation was absent in all populations (i.e., each population consisted of a single multilocus genotype (MLG or "clone" and the genetic composition of only one population completely changed across years. There was no evidence of sexual reproduction or host races on different plant species. CONCLUSIONS/SIGNIFICANCE: Aphis nerii is a well established invasive species despite having extremely low genetic diversity. As this aphid appears to be obligatorily asexual, it may share more similarities with clonally reproducing invasive plants, than with other animals. Patterns of temporal and geographic genetic variation, viewed in the context of its population dynamics, have important implications for the management of invasive pests and the evolutionary biology of asexual species.

  17. Ants farm subterranean aphids mostly in single clone groups - an example of prudent husbandry for carbohydrates and proteins?

    Directory of Open Access Journals (Sweden)

    Ivens Aniek BF

    2012-07-01

    Full Text Available Abstract Background Mutualistic interactions are wide-spread but the mechanisms underlying their evolutionary stability and ecological dynamics remain poorly understood. Cultivation mutualisms in which hosts consume symbionts occur in phylogenetically diverse groups, but often have symbiont monocultures for each host. This is consistent with the prediction that symbionts should avoid coexistence with other strains so that host services continue to benefit relatives, but it is less clear whether hosts should always favor monocultures and what mechanisms they might have to manipulate symbiont diversity. Few mutualisms have been studied in sufficient genetic detail to address these issues, so we decided to characterize symbiont diversity in the complex mutualism between multiple root aphid species and Lasius flavus ants. After showing elsewhere that three of these aphid species have low dispersal and mostly if not exclusively asexual reproduction, we here investigate aphid diversity within and between ant nest mounds. Results The three focal species (Geoica utricularia, Forda marginata and Tetraneura ulmi had considerable clonal diversity at the population level. Yet more than half of the ant mounds contained just a single aphid species, a significantly higher percentage than expected from a random distribution. Over 60% of these single-species mounds had a single aphid clone, and clones tended to persist across subsequent years. Whenever multiple species/clones co-occurred in the same mound, they were spatially separated with more than 95% of the aphid chambers containing individuals of a single clone. Conclusions L. flavus “husbandry” is characterized by low aphid “livestock” diversity per colony, especially at the nest-chamber level, but it lacks the exclusive monocultures known from other cultivation mutualisms. The ants appear to eat most of the early instar aphids, so that adult aphids are unlikely to face limited phloem resources and

  18. Reciprocal assistance for aphid transmission between non-transmissible strains of zucchini yellow mosaic potyvirus in mixed infections. Brief report.

    Science.gov (United States)

    Desbiez, C; Wipf-Scheibel, C; Lecoq, H

    1999-01-01

    Several aphid non-transmissible strains of zucchini yellow mosaic potyvirus (ZYMV) have been described, in relation with mutations in the two viral proteins required for transmissibility, coat protein and helper component. Assistance mechanisms were previously shown to allow transmission of such strains when functional proteins are provided in trans. In this paper, we used monoclonal antibodies to allow a specific detection of two aphid non-transmissible strains of ZYMV and we revealed that reciprocal assistance mechanisms can mediate simultaneous aphid transmission of these deficient strains. Potential epidemiological and evolutive consequences of such assistance mechanisms between variants in complex virus populations are discussed. PMID:10603175

  19. Genetics coupled to quantitative intact proteomics links heritable aphid and endosymbiont protein expression to circulative polerovirus transmission.

    Science.gov (United States)

    Cilia, M; Tamborindeguy, C; Fish, T; Howe, K; Thannhauser, T W; Gray, S

    2011-03-01

    Yellow dwarf viruses in the family Luteoviridae, which are the causal agents of yellow dwarf disease in cereal crops, are each transmitted most efficiently by different species of aphids in a circulative manner that requires the virus to interact with a multitude of aphid proteins. Aphid proteins differentially expressed in F2 Schizaphis graminum genotypes segregating for the ability to transmit Cereal yellow dwarf virus-RPV (CYDV-RPV) were identified using two-dimensional difference gel electrophoresis (DIGE) coupled to either matrix-assisted laser desorption ionization-tandem mass spectrometry or online nanoscale liquid chromatography coupled to electrospray tandem mass spectrometry. A total of 50 protein spots, containing aphid proteins and proteins from the aphid's obligate and maternally inherited bacterial endosymbiont, Buchnera, were identified as differentially expressed between transmission-competent and refractive aphids. Surprisingly, in virus transmission-competent F2 genotypes, the isoelectric points of the Buchnera proteins did not match those in the maternal Buchnera proteome as expected, but instead they aligned with the Buchnera proteome of the transmission-competent paternal parent. Among the aphid proteins identified, many were involved in energy metabolism, membrane trafficking, lipid signaling, and the cytoskeleton. At least eight aphid proteins were expressed as heritable, isoelectric point isoform pairs, one derived from each parental lineage. In the F2 genotypes, the expression of aphid protein isoforms derived from the competent parental lineage aligned with the virus transmission phenotype with high precision. Thus, these isoforms are candidate biomarkers for CYDV-RPV transmission in S. graminum. Our combined genetic and DIGE approach also made it possible to predict where several of the proteins may be expressed in refractive aphids with different barriers to transmission. Twelve proteins were predicted to act in the hindgut of the aphid

  20. Parasitoids (Hymenoptera: Braconidae: Aphidiinae) of northeastern Iran: aphidiine-aphid-plant associations, key and description of a new species.

    Science.gov (United States)

    Rakhshani, Ehsan; Kazemzadeh, Sedigheh; Starý, Petr; Barahoei, Hossein; Kavallieratos, Nickolas G; Ćetković, Aleksandar; Popović, Anđelka; Bodlah, Lmran; Tomanović, Željko

    2012-01-01

    Aphid parasitoids of the subfamily Aphidiinae (Hymenoptera: Braconidae) of northeastern Iran were studied in this paper. A total of 29 species are keyed and illustrated with line drawings. The aphidiines presented in this work have been reared from 42 aphid host taxa occurring on 49 plant taxa from a total of 33 sampling sites. Sixty-six aphidiine-aphid-plant associations are presented. Trioxys metacarpalis sp. nov. from Chaitaphis tenuicaudata Nevsky (Hemiptera: Aphididae) on Kochia scoparia, is described. The species diversity based on the comparative faunistic analysis is discussed. PMID:23463939

  1. Shallot Aphids, Myzus ascalonicus, in Strawberry: Biocontrol Potential of Three Predators and Three Parasitoids

    DEFF Research Database (Denmark)

    Enkegaard, Annie; Sigsgaard, Lene; Kristensen, Kristian

    2013-01-01

    or sweet pepper leaves. The aphid species and the plant species did not, however, have a significant influence on the number of females laying eggs, the average number of eggs laid during the first day being 6.37±1.28 per female. Adult lady beetles had a significant preference for odor from controls...... without plants over odors from uninfested strawberry or pepper plants, but they showed no preference for either of the plant species, whether infested with aphids or not. The predation capacity of A. bipunctata on shallot aphids holds promise for its use in inundative biocontrol, and the results on egg...

  2. Energy budgets of the Chinese green lacewing (Neuroptera: Chrysopidae) and its potential for biological control of the cotton aphid (Homoptera: Aphididae)

    Institute of Scientific and Technical Information of China (English)

    FENG GAO; XIANG-HUI LIU; FENG GE

    2007-01-01

    Energy budgets of larval stages of the Chinese green lacewing, Chrysopa sinica (Tjeder) (Neuroptera: Chrysopidae) were determined under laboratory conditions at photoperiod of 14:10 L:D, 27±1℃ and 75%±2% RH. The energy used as ingestion,assimilation, respiration, productivity and feces was constructed for each developmental stage. In addition, under these experimental conditions, the potential of C.sinica as a biological control agent was evaluated according to the ingestion by this predator and the energy content of cotton aphid, Aphis gossypii (Glover) (Homoptera: Aphididae). The larval stage of C. sinica was able to consume 1281.4 1-day-old aphids, 1018.7 2-day-old aphids,626.9 3-day-old aphids, 393.5 4-day-old aphids, 312.1 5-day-old aphids or 203.5 9-day-old aphids, respectively. No significant difference was detected between the estimated number of aphids consumed by the lacewings using energetic methods and the actual number of aphids consumed by the lacewings in this experiment. Our results showed that C. sinica is an important natural enemy of the cotton aphid, and energetic methods are very useful to quantify biological control efficacy of natural enemies.

  3. Metabolic Engineering of Plant-derived (E)-β-farnesene Synthase Genes for a Novel Type of Aphid-resistant Genetically Modified Crop Plants

    Institute of Scientific and Technical Information of China (English)

    Xiu-Dao Yu; John Pickett; You-Zhi Ma; Toby Bruce; Johnathan Napier; Huw D.Jones; Lan-Qin Xia

    2012-01-01

    Aphids are major agricultural pests that cause significant yield losses of crop plants each year.Excessive dependence on insecticides for long-term aphid control is undesirable because of the development of insecticide resistance,the potential negative effects on non-target organisms and environmental pollution.Transgenic crops engineered for resistance to aphids via a non-toxic mode of action could be an efficient alternative strategy.(E)-β-Farnesene (EβF) synthases catalyze the formation of EβF,which for many pest aphids is the main component of the alarm pheromone involved in the chemical communication within these species.EβF can also be synthesized by certain plants but is then normally contaminated with inhibitory compounds.Engineering of crop plants capable of synthesizing and emitting EβF could cause repulsion of aphids and also the attraction of natural enemies that use EβF as a foraging cue,thus minimizing aphid infestation.In this review,the effects of aphids on host plants,plants' defenses against aphid herbivory and the recruitment of natural enemies for aphid control in an agricultural setting are briefly introduced.Furthermore,the plant-derived EβF synthase genes cloned to date along with their potential roles in generating novel aphid resistance via genetically modified approaches are discussed.

  4. First Complete Genome Sequence of Suakwa aphid-borne yellows virus from East Timor.

    Science.gov (United States)

    Maina, Solomon; Edwards, Owain R; de Almeida, Luis; Ximenes, Abel; Jones, Roger A C

    2016-01-01

    We present here the first complete genomic RNA sequence of the polerovirus Suakwa aphid-borne yellows virus (SABYV), from East Timor. The isolate sequenced came from a virus-infected pumpkin plant. The East Timorese genome had a nucleotide identity of 86.5% with the only other SABYV genome available, which is from Taiwan. PMID:27469955

  5. Registration of ‘Wyandot-14’ soybean with resistance to soybean aphid and powdery mildew

    Science.gov (United States)

    ‘Wyandot-14’ soybean [Glycine max (L.) Merr.] with resistance to soybean aphid biotypes 1 and 2 and resistance to powdery mildew was jointly released by the USDA-Agricultural Research Service and The Ohio Agricultural Research and Development Center (OARDC) as a late maturity group (MG) II (2.9) foo...

  6. Heterodera schachtii nematodes interfere with aphid-plant relations on Brassica oleracea

    NARCIS (Netherlands)

    Hol, W.H.G.; Boer, de W.; Termorshuizen, A.J.; Meyer, K.M.; Schneider, J.H.M.; Putten, van der W.H.; Dam, N.M.

    2013-01-01

    Aboveground and belowground herbivore species modify plant defense responses differently. Simultaneous attack can lead to non-additive effects on primary and secondary metabolite composition in roots and shoots. We previously found that aphid (Brevicoryne brassicae) population growth on Brassica ole

  7. The aphid Melanaphis sacchari and the weed Sorghum almum – Partners in crime

    Science.gov (United States)

    Sugarcane yellow leaf virus (SCYLV), the causal agent of yellow leaf disease of sugarcane, is widespread in Florida and vectored by the aphid Melanaphis sacchari. Sugarcane was the only known natural host of SCYLV in the USA until 2015 when a new natural host was found for this virus in Florida: Sor...

  8. Which shrubs and trees can conserve natural enemies of aphids in spring?

    NARCIS (Netherlands)

    P.C.J. van Rijn

    2014-01-01

    Habitats with shrubs and trees within the agricultural landscape may contribute to the maintenance of natural enemies of pests. Aphids and flowers are important resources for beneficial natural enemies such as ladybeetles, hoverflies and lacewings. Woody plants are the most likely candidates to prov

  9. Changes in large-scale climate alter spatial synchrony of aphid pests

    Science.gov (United States)

    Sheppard, Lawrence W.; Bell, James R.; Harrington, Richard; Reuman, Daniel C.

    2016-06-01

    Spatial synchrony, the tendency of distant populations to fluctuate similarly, is a major concern in ecology. Except in special circumstances, researchers historically had difficulty identifying drivers of synchrony in field systems. Perhaps for this reason, the possibility that changes in large-scale climatic drivers may modify synchrony, thereby impacting ecosystems and human concerns, has been little examined. Here, we use wavelets to determine environmental drivers of phenological synchrony across Britain for 20 aphid species, most major crop pests. Consistently across species, changes in drivers produced large changes in aphid synchrony. Different drivers acted on different timescales: using a new wavelet analogue of the Moran theorem, we show that on long timescales (>4 years), 80% of synchrony in aphid first flights is due to synchrony in winter climate; but this explanation accounts for less short-timescale (Changes in aphid synchrony over time also differed by timescale: long-timescale synchrony fell from before 1993 to after, caused by similar changes in winter climate; whereas short-timescale synchrony increased. Shifts in winter climate are attributable to the North Atlantic Oscillation, an important climatic phenomenon, so effects described here may influence other taxa. This study documents a new way that climatic changes influence populations, through altered Moran effects.

  10. Evaluation and reselection of wheat resistance to Russian wheat aphid biotype 2

    Science.gov (United States)

    Russian wheat aphid (RWA, Diuraphis noxia, Mordvilko) biotype 2 (RWA2) is virulent to most known RWA resistance genes and severely threatens wheat production in the hard winter wheat area of the US western Great Plains. We determined RWA2 reactions of 386 cultivars from China, 227 advanced breeding...

  11. Reproduction and Population Dynamics as Biotypic Markers of Russian Wheat Aphid Diuraphis noxia (Kurdjumov

    Directory of Open Access Journals (Sweden)

    Watson Ngenya

    2016-04-01

    Full Text Available Russian wheat aphid Diuraphis noxia (Kurdjumov is widely established in wheat-growing countries where it causes significant economic losses. The development and use of Russian wheat aphid (RWA-resistant wheat varieties has been constrained by the variation in resident RWA populations and the evolution of virulent biotypes. An experiment was set up at the Kenya Agricultural and Livestock Research Organization (KALRO, Njoro, to characterize RWA populations based on phenotypic characteristics of reproduction, development and population dynamics. RWA populations from the regions of Eldoret, Mau Narok and Njoro were used in the study. A factorial experiment was set up in randomized complete block design replicated eleven times. A single day-old nymph was placed on a new, fully-open leaf in a 0.5 cm-diameter clear plastic straw leaf cage and observed daily for its entire lifetime. The results showed that there were variations in aphid lifespan, reproductive longevity and aphid fecundity between populations, indicating that the phenotypic markers used to determine biotypes were good enough to show distinct biotypes among populations of the RWA in Kenya. Further, the study concluded that the use of phenotypic life and reproductive markers was a valid way of characterizing biotypes of RWA worldwide.

  12. Why the aphid Aphis spiraecola is more abundant on clementine tree than Aphis gossypii?

    Science.gov (United States)

    Mostefaoui, Houda; Allal-Benfekih, Leila; Djazouli, Zahr-Eddine; Petit, Daniel; Saladin, Gaëlle

    2014-02-01

    Aphis spiraecola and Aphis gossypii cause harmful damages on clementine tree orchards. Weekly surveys measured the abundance of aphids (larvae, winged and wingless adults) as well as of auxiliary insects and parameters of energy metabolism. Correlatively, soluble carbohydrates, total free amino acids, free proline and condensed tannins were quantified in control and infested leaves. Both aphid species showed parallel temporal variations, but A. spiraecola was consistently more abundant regardless of the stage. Amino acids had a positive effect on both aphid species abundance, but neither condensed tannins nor auxiliary insects seemed to modulate aphid populations. Interestingly, the leaf carbohydrate content was positively correlated with the abundance of A. spiraecola, but not with that of A. gossypii. Moreover, A. gossypii's abundance was significantly down-regulated by high proline concentrations. Thus, the higher abundance of A. spiraecola could be explained by a better tolerance to high proline contents and a better conversion of foliar energy metabolites.

  13. Enhancement of resistance to aphids by introducing the snowdrop lectin gene gna into maize plants.

    Science.gov (United States)

    Wang, Zhaoyu; Zhang, Kewei; Sun, Xiaofen; Tang, Kexuan; Zhang, Juren

    2005-12-01

    In order to enhance the resistance to pests, transgenic maize (Zea mays L.) plants from elite inbred lines containing the gene encoding snowdrop lectin (Galanthus nivalis L. agglutinin; GNA) under control of a phloem-specific promoter were generated through the Agrobacterium tumefaciens-mediated method. The toxicity of GNA-expressing plants to aphids has also been studied. The independently derived plants were subjected to molecular analyses. Polymerase chain reaction (PCR) and Southern blot analyses confirmed that the gna gene was integrated into maize genome and inherited to the following generations. The typical Mendelian patterns of inheritance occurred in most cases. The level of GNA expression at 0.13%-0.28% of total soluble protein was observed in different transgenic plants. The progeny of nine GNA-expressing independent transformants that were derived separately from the elite inbred lines DH4866, DH9942, and 8902, were selected for examination of resistance to aphids. These plants synthesized GNA at levels above 0.22% total soluble protein, and enhanced resistance to aphids was demonstrated by exposing the plants to corn leaf aphid (Rhopalosiphum maidis Fitch) under greenhouse conditions. The nymph production was significantly reduced by 46.9% on GNA-expressing plants. Field evaluation of the transgenic plants supported the results from the inoculation trial. After a series of artificial self-crosses, some homozygous transgenic maize lines expressing GNA were obtained. In the present study, we have obtained new insect-resistant maize material for further breeding work.

  14. [Study on transformation of snowdrop lectin gene to chrysanthemum and aphid resistance of the transgenic plants].

    Science.gov (United States)

    Wang, Guan-Lin; Liu, Yan-Hong; Guo, Shao-Hua; Wang, Yu; Ji, Yan; Fang, Hong-Jun

    2004-12-01

    Agrobacterium-mediated transformation in chrysanthemum was studied to prevent the insect pest of aphid (Mizus persicae). The gna gene was successfully transferred into chrysanthemum by leaf dish, and 93 transgenic clones were obtained. The highest transformation frequency 11.21% was achieved on the optimization facts, which were medium YEB with pH5.6, bacterial concentration OD600 = 0.4, precultivation for one day, cocultivation for four days, the cocultivation media supplemented with GA3 0.5 mg/L and leaf explants growed for 45 days. The results from PCR and FQ-PCR analysis confirmed that gna gene was integrated into the genome of chrysanthemum plants. The insect bioassay with aphid showed that the aphid resistance of different transgenic plants was difference, and the rate of aphid population inhibition of them were from 10% to 84% with an average rate of 39.4%. The leaf-extracts from different transgenic plants showed varying actinties in red-blood cell bioassay.

  15. A possible novel black aphid control approach using plant growth regulators

    Science.gov (United States)

    The black pecan aphid, Melanocallis caryaefoliae (Davis) (Hemiptera: Aphididae), elicits localized chlorotic injury to pecan foliage in order to feed, thereby accelerating leaf senescence and defoliation. The action of certain plant growth regulators (i.e., forchlorfenuron, gibberellic acid and avi...

  16. Reproduction and Population Dynamics as Biotypic Markers of Russian Wheat Aphid Diuraphis noxia (Kurdjumov).

    Science.gov (United States)

    Ngenya, Watson; Malinga, Joyce; Tabu, Isaiah; Masinde, Emily

    2016-01-01

    Russian wheat aphid Diuraphis noxia (Kurdjumov) is widely established in wheat-growing countries where it causes significant economic losses. The development and use of Russian wheat aphid (RWA)-resistant wheat varieties has been constrained by the variation in resident RWA populations and the evolution of virulent biotypes. An experiment was set up at the Kenya Agricultural and Livestock Research Organization (KALRO), Njoro, to characterize RWA populations based on phenotypic characteristics of reproduction, development and population dynamics. RWA populations from the regions of Eldoret, Mau Narok and Njoro were used in the study. A factorial experiment was set up in randomized complete block design replicated eleven times. A single day-old nymph was placed on a new, fully-open leaf in a 0.5 cm-diameter clear plastic straw leaf cage and observed daily for its entire lifetime. The results showed that there were variations in aphid lifespan, reproductive longevity and aphid fecundity between populations, indicating that the phenotypic markers used to determine biotypes were good enough to show distinct biotypes among populations of the RWA in Kenya. Further, the study concluded that the use of phenotypic life and reproductive markers was a valid way of characterizing biotypes of RWA worldwide. PMID:27049398

  17. Resistance to Cucurbit aphid-borne yellows virus in Melon Accession TGR-1551.

    Science.gov (United States)

    Kassem, Mona A; Gosalvez, Blanca; Garzo, Elisa; Fereres, Alberto; Gómez-Guillamón, Maria Luisa; Aranda, Miguel A

    2015-10-01

    The genetic control of resistance to Cucurbit aphid-borne yellows virus (CABYV; genus Polerovirus, family Luteoviridae) in the TGR-1551 melon accession was studied through agroinoculation of a genetic family obtained from the cross between this accession and the susceptible Spanish cultivar 'Bola de Oro'. Segregation analyses were consistent with the hypothesis that one dominant gene and at least two more modifier genes confer resistance; one of these additional genes is likely present in the susceptible parent 'Bola de Oro'. Local and systemic accumulation of the virus was analyzed in a time course experiment, showing that TGR-1551 resistance was expressed systemically as a significant reduction of virus accumulation compared with susceptible controls, but not locally in agroinoculated cotyledons. In aphid transmission experiments, CABYV inoculation by aphids was significantly reduced in TGR-1551 plants, although the virus was acquired at a similar rate from TGR-1551 as from susceptible plants. Results of feeding behavior studies using the DC electrical penetration graph technique suggested that viruliferous aphids can salivate and feed from the phloem of TGR-1551 plants and that the observed reduction in virus transmission efficiency is not related to reduced salivation by Aphis gossypii in phloem sieve elements. Since the virus is able to accumulate to normal levels in agroinoculated tissues, our results suggest that resistance of TGR-1551 plants to CABYV is related to impairment of virus movement or translocation after it reaches the phloem sieve elements.

  18. Registration of 'Stoneham' spring feed barley resistant to Russian wheat aphid

    Science.gov (United States)

    'Stoneham' (REG. No.; PI 641940) a Russian wheat aphid (RWA, Diuraphis noxia Kurdjumov)-resistant, spring, two-rowed, feed barley (Hordeum vulgare) tested as 97BX 27-132, was developed and released by the USDA-ARS, Stillwater, OK and Aberdeen, ID; Colorado State University; and the University of Neb...

  19. Response of Green Peach Aphids and Other Arthropods to Garlic Intercropped with Tobacco

    NARCIS (Netherlands)

    Lai, R.; You, M.; Lotz, L.A.P.; Vasseur, L.

    2011-01-01

    The green peach aphid, Myzus persicae (Sulzer), is an insect pest that causes extensive damage to tobacco (Nicotiana tabacum L.) in China. Field trials were conducted in 2008 and 2009 at Longyan in the Fujian Province (China) to evaluate the effects of garlic (Allium sativum L.) as a deterrent to gr

  20. Evaluation of mirid predatory bugs and release strategy for aphid control in sweet pepper

    NARCIS (Netherlands)

    Messelink, G.J.; Bloemhard, C.M.J.; Hoogerbrugge, H.; Schelt, van J.; Ingegno, B.L.; Tavella, L.

    2015-01-01

    Zoophytophagous predators of the family Miridae (Heteroptera), which feed both on plant and prey, often maintain a close relationship with certain host plants. In this study, we aimed to select a suitable mirid predatory bug for aphid control in sweet pepper. Four species were compared: Macrolophus

  1. Adaptive significance of gall formation for a gall-inducing aphids on Japanese elm trees.

    Science.gov (United States)

    Takei, Mami; Yoshida, Sayaka; Kawai, Takashi; Hasegawa, Morifumi; Suzuki, Yoshihito

    2015-01-01

    Insect galls are abnormal plant tissues induced by external stimuli from parasitizing insects. It has been suggested that the stimuli include phytohormones such as auxin and cytokinins produced by the insects. In our study on the role of hormones in gall induction by the aphid Tetraneura nigriabdominalis, it was found that feedback regulation related to auxin and cytokinin activity is absent in gall tissues, even though the aphids contain higher concentrations of those phytohormones than do plant tissues. Moreover, jasmonic acid signaling appears to be compromised in gall tissue, and consequently, the production of volatile organic compounds, which are a typical defense response of host plants to herbivory, is diminished. These findings suggest that these traits of the gall tissue benefit aphids, because the gall tissue is highly sensitive to auxin and cytokinin, which induce and maintain it. The induced defenses against aphid feeding are also compromised. The abnormal responsiveness to phytohormones is regarded as a new type of extended phenotype of gall-inducing insects. PMID:25437243

  2. Trade-Off Between Fitness Gain and Cost Determines Profitability of a Peach Aphid Parasitoid.

    Science.gov (United States)

    Khatri, Diwas; He, Xiong Z; Wang, Qiao

    2016-08-01

    Aphidius colemani (Viereck) (Hymenoptera: Aphidiidae) is commercially produced and utilized for biological control of peach aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) on greenhouse crops in many countries. To provide knowledge for the evaluation of parasitoid-host interactions and development of effective mass rearing programs, we investigated how and why host age or size affected fitness gain in A. colemani We show that the parasitoid was significantly more likely to encounter larger hosts and that an encounter almost always triggered an attack attempt. However, the attack attempt did not proportionally translate into oviposition because larger aphids had greater ability to defend themselves and the parasitoid spent more time in handling larger aphids. The host age at parasitization had no effect on emergence rates and sex ratio of parasitoid progeny, suggesting that pupae and larvae have similar survival rate in hosts of different ages and/or the parasitoid females do not adjust sex allocation based on host size. When parasitizing mid-aged hosts, the parasitoid gained maximum fitness for their progeny in developmental period, body size, and parasitism. Taking all findings together, we suggest that parasitizing mid-aged green peach aphid nymphs is most profitable for A. colemani. PMID:27289084

  3. Subcellular location of the helper component-proteinase of Cowpea Aphid-Borne Mosaic Virus

    NARCIS (Netherlands)

    Mlotshwa, S.; Verver, J.; Sithole-Niang, I.; Gopinath, K.; Carette, J.; Kammen, van A.; Wellink, J.

    2002-01-01

    The helper component-proteinase (HC-Pro) of Cowpea aphid-borne mosaic virus (CABMV) was expressed in Escherichia coli and used to obtain HC-Pro antiserum that was used as an analytical tool for HC-Pro studies. The antiserum was used in immunofluorescence assays to study the subcellular location of H

  4. Characterization and genetic dissection of resistance to spotted alfalfa aphid (Therioaphis trifolii) in Medicago truncatula

    KAUST Repository

    Kamphuis, L. G.

    2013-09-21

    Aphids cause significant yield losses in agricultural crops worldwide. Medicago truncatula, a model legume, cultivated pasture species in Australia and close relative of alfalfa (Medicago sativa), was used to study the defence response against Therioaphis trifolii f. maculate [spotted alfalfa aphid (SAA)]. Aphid performance and plant damage were compared among three accessions. A20 is highly susceptible, A17 has moderate resistance, and Jester is strongly resistant. Subsequent analyses using A17 and A20, reciprocal F1s and an A17×A20 recombinant inbred line (RIL) population revealed that this moderate resistance is phloem mediated and involves antibiosis and tolerance but not antixenosis. Electrical penetration graph analysis also identified a novel waveform termed extended potential drop, which occurred following SAA infestation of M. truncatula. Genetic dissection using the RIL population revealed three quantitative trait loci on chromosomes 3, 6, and 7 involved in distinct modes of aphid defence including antibiosis and tolerance. An antibiosis locus resides on linkage group 3 (LG3) and is derived from A17, whereas a plant tolerance and antibiosis locus resides on LG6 and is derived from A20, which exhibits strong temporary tolerance. The loci identified reside in regions harbouring classical resistance genes, and introgression of these loci in current medic cultivars may help provide durable resistance to SAA, while elucidation of their molecular mechanisms may provide valuable insight into other aphid–plant interactions.

  5. Effects of Insecticides on Strawberry Aphid Chaetosiphon fragaefolii (Cockerell) on Resistant and Susceptible Strawberry Genotypes

    OpenAIRE

    Slobodan Milenković; Dejan Marčić; Pantelija Perić

    2011-01-01

    Strawberry aphid, Chaetosiphon fragaefolii (Cockerell), is the most important vector of strawberry virus. Breeding of genotypes resistant to this pest is an important preventive control measure, which can be compatible with rational insecticide application. The aim of the paper was to determine effects of dimethoate and deltamethrin on C. fragaefolii populations reared on two strawberry genotypes different in susceptibility: susceptible strawberry cultivar ...

  6. Proteins involved in attack and defence in Zygomycete-aphid interactions

    DEFF Research Database (Denmark)

    Grell, Morten Nedergaard; Jensen, Annette Bruun; Lange, Lene

    2009-01-01

    a secretome study of field collected grain aphids (Sitobion avenae) in early stages of infection with entomophthoralean fungi using the transposon assisted signal trapping (TAST) technology (Becker et al. 2004, J Microbiol Methods 57, 123-133), thereby discovering a series of secreted enzymes of the pathogens...

  7. Enhancement of resistance to aphids by introducing the snowdrop lectin gene gna into maize plants

    Indian Academy of Sciences (India)

    Zhaoyu Wang; Kewei Zhang; Xiaofen Sun; Kexuan Tang; Juren Zhang

    2005-12-01

    In order to enhance the resistance to pests, transgenic maize (Zea mays L.) plants from elite inbred lines containing the gene encoding snowdrop lectin (Galanthus nivalis L. agglutinin; GNA) under control of a phloemspecific promoter were generated through the Agrobacterium tumefaciens-mediated method. The toxicity of GNA-expressing plants to aphids has also been studied. The independently derived plants were subjected to molecular analyses. Polymerase chain reaction (PCR) and Southern blot analyses confirmed that the gna gene was integrated into maize genome and inherited to the following generations. The typical Mendelian patterns of inheritance occurred in most cases. The level of GNA expression at 0.13%–0.28% of total soluble protein was observed in different transgenic plants. The progeny of nine GNA-expressing independent transformants that were derived separately from the elite inbred lines DH4866, DH9942, and 8902, were selected for examination of resistance to aphids. These plants synthesized GNA at levels above 0.22% total soluble protein, and enhanced resistance to aphids was demonstrated by exposing the plants to corn leaf aphid (Rhopalosiphum maidis Fitch) under greenhouse conditions. The nymph production was significantly reduced by 46.9% on GNA-expressing plants. Field evaluation of the transgenic plants supported the results from the inoculation trial. After a series of artificial self-crosses, some homozygous transgenic maize lines expressing GNA were obtained. In the present study, we have obtained new insect-resistant maize material for further breeding work.

  8. Wild tomato leaf extracts for spider mite and cowpea aphid control.

    Science.gov (United States)

    Antonious, George F; Kamminga, Katherine; Snyder, John C

    2014-01-01

    Glandular trichomes on the leaves of wild tomato, L. hirsutum f. hirsutum Mull, also known as Solanum habrochaites (Solanaceae), synthesize and accumulate high levels of methyl ketones (MKs). L. hirsutum accession LA 407, having high concentration of MKs, was grown from seeds under greenhouse conditions. Four MKs (2-undecanone, 2-dodecanone, 2-tridecanone, and 2-pentadecanone) were screened for their toxicity to spider mites, Tetranychus urticae Koch and cowpea aphids, Aphis craccivora Koch. The objectives of this investigation were to: (1) develop a bioassay for testing MKs on spider mite and cowpea aphid mortality and (2) compare the efficacies of wild tomato leaf crude extracts and pure standard materials of MKs against spider mite and cowpea aphid mortality. Our results revealed that spider mites are most sensitive to 2-tridecanone (LC50 = 0.08 μmole cm(-2) of treated leaf surface) and least sensitive to 2-undecanone (LC50 = 1.5 μmole cm(-2) of treated leaf surface) 4 h after treatment. Similarly, 2-tridecanone caused greatest mortality (LC50 = 0.2 μmole cm(-2) of treated leaf surface), whereas 2-undecanone caused the lowest morality (LC50 = 0.48 μmole cm(-2) of treated surface) of cowpea aphid. We concluded that all MKs tested in this investigation are toxic to spider mites and aphids. 2-Tridecanone is more effective in killing mites and aphids compared to other MKs. Toxicity of crude extracts, prepared from the leaves of L. hirsutum accession LA 407, to spider mites and cowpea aphids revealed greater mortality compared to a combined mixture of MKs standard material (used at the same concentration as found on LA 407 leaves). This indicates that in addition to MKs, other unidentified compounds in LA 407 leaf extract also have pesticidal properties. Accordingly, leaf extracts of LA 407 could be explored in crop protection, and they might open a new area of MK formulations and discovery of biorational alternatives for pest control in agricultural fields. PMID

  9. Wild tomato leaf extracts for spider mite and cowpea aphid control.

    Science.gov (United States)

    Antonious, George F; Kamminga, Katherine; Snyder, John C

    2014-01-01

    Glandular trichomes on the leaves of wild tomato, L. hirsutum f. hirsutum Mull, also known as Solanum habrochaites (Solanaceae), synthesize and accumulate high levels of methyl ketones (MKs). L. hirsutum accession LA 407, having high concentration of MKs, was grown from seeds under greenhouse conditions. Four MKs (2-undecanone, 2-dodecanone, 2-tridecanone, and 2-pentadecanone) were screened for their toxicity to spider mites, Tetranychus urticae Koch and cowpea aphids, Aphis craccivora Koch. The objectives of this investigation were to: (1) develop a bioassay for testing MKs on spider mite and cowpea aphid mortality and (2) compare the efficacies of wild tomato leaf crude extracts and pure standard materials of MKs against spider mite and cowpea aphid mortality. Our results revealed that spider mites are most sensitive to 2-tridecanone (LC50 = 0.08 μmole cm(-2) of treated leaf surface) and least sensitive to 2-undecanone (LC50 = 1.5 μmole cm(-2) of treated leaf surface) 4 h after treatment. Similarly, 2-tridecanone caused greatest mortality (LC50 = 0.2 μmole cm(-2) of treated leaf surface), whereas 2-undecanone caused the lowest morality (LC50 = 0.48 μmole cm(-2) of treated surface) of cowpea aphid. We concluded that all MKs tested in this investigation are toxic to spider mites and aphids. 2-Tridecanone is more effective in killing mites and aphids compared to other MKs. Toxicity of crude extracts, prepared from the leaves of L. hirsutum accession LA 407, to spider mites and cowpea aphids revealed greater mortality compared to a combined mixture of MKs standard material (used at the same concentration as found on LA 407 leaves). This indicates that in addition to MKs, other unidentified compounds in LA 407 leaf extract also have pesticidal properties. Accordingly, leaf extracts of LA 407 could be explored in crop protection, and they might open a new area of MK formulations and discovery of biorational alternatives for pest control in agricultural fields.

  10. Aboveground feeding by soybean aphid, Aphis glycines, affects soybean cyst nematode, Heterodera glycines, reproduction belowground.

    Directory of Open Access Journals (Sweden)

    Michael T McCarville

    Full Text Available Heterodera glycines is a cyst nematode that causes significant lost soybean yield in the U.S. Recent studies observed the aphid Aphis glycines and H. glycines interacting via their shared host, soybean, Glycine max. A greenhouse experiment was conducted to discern the effect of A. glycines feeding on H. glycines reproduction. An H. glycines-susceptible cultivar, Kenwood 94, and a resistant cultivar, Dekalb 27-52, were grown in H. glycines-infested soil for 30 and 60 d. Ten days after planting, plants were infested with either zero, five, or ten aphids. At 30 and 60 d, the number of H. glycines females and cysts (dead females and the number of eggs within were counted. In general, H. glycines were less abundant on the resistant than the susceptible cultivar, and H. glycines abundance increased from 30 to 60 d. At 30 d, 33% more H. glycines females and eggs were produced on the resistant cultivar in the ten-aphid treatment compared to the zero-aphid treatment. However, at 30 d the susceptible cultivar had 50% fewer H. glycines females and eggs when infested with ten aphids. At 60 d, numbers of H. glycines females and cysts and numbers of eggs on the resistant cultivar were unaffected by A. glycines feeding, while numbers of both were decreased by A. glycines on the susceptible cultivar. These results indicate that A. glycines feeding improves the quality of soybean as a host for H. glycines, but at higher herbivore population densities, this effect is offset by a decrease in resource quantity.

  11. Resistance of Wheat Accessions to the English Grain Aphid Sitobion avenae.

    Science.gov (United States)

    Hu, Xiang-Shun; Liu, Ying-Jie; Wang, Yu-Han; Wang, Zhe; Yu, Xin-Lin; Wang, Bo; Zhang, Gai-Sheng; Liu, Xiao-Feng; Hu, Zu-Qing; Zhao, Hui-Yan; Liu, Tong-Xian

    2016-01-01

    The English grain aphid, Sitobion avenae, is a major pest species of wheat crops; however, certain varieties may have stronger resistance to infestation than others. Here, we investigated 3 classical resistance mechanisms (antixenosis, antibiosis, and tolerance) by 14 wheat varieties/lines to S. avenae under laboratory and field conditions. Under laboratory conditions, alatae given the choice between 2 wheat varieties, strongly discriminated against certain varieties. Specifically, the 'Amigo' variety had the lowest palatability to S. avenae alatae of all varieties. 'Tm' (Triticum monococcum), 'Astron,' 'Xanthus,' 'Ww2730,' and 'Batis' varieties also had lower palatability than other varieties. Thus, these accessions may use antibiosis as the resistant mechanism. In contrast, under field conditions, there were no significant differences in the number of alatae detected on the 14 wheat varieties. One synthetic line (98-10-30, a cross between of Triticum aestivum (var. Chris) and Triticum turgidum (var. durum) hybridization) had low aphid numbers but high yield loss, indicating that it has high antibiosis, but poor tolerance. In comparison, 'Amigo,' 'Xiaoyan22,' and some '186Tm' samples had high aphid numbers but low yield loss rates, indicating they have low antibiosis, but good tolerance. Aphid population size and wheat yield loss rates greatly varied in different fields and years for '98-10-35,' 'Xiaoyan22,' 'Tp,' 'Tam200,' 'PI high,' and other '186Tm' samples, which were hybrid offspring of T. aestivum and wheat related species. Thus, these germplasm should be considered for use in future studies. Overall, S. avenae is best adapted to 'Xinong1376,' because it was the most palatable variety, with the greatest yield loss rates of all 14 wheat varieties. However, individual varieties/lines influenced aphid populations differently in different years. Therefore, we strongly recommend a combination of laboratory and long-term field experiments in targeted planting

  12. Effect of exogenous supply of boron on nodule development in pea (pisum sativum L.)

    International Nuclear Information System (INIS)

    Exogenous supply of boron was evaluated on the seeds of Pisum sativum L. inoculated with Rhizobium leguminosarum and grown in aqua-culture. The liquid nutrition medium contained six boron concentrations (control, 1, 1.86, 2.86, 3.86, and 4.86 mg L/sup -1/ ). The results obtained from the present work showed that number of nodules, size of nodules and weight of boron treatment. Toxic effect of high concentration of boron (4.86 mg L/sup -1/ ) nodules exhibit great improvement in 2.86 mg L /sup-1/ was also recorded. There was significant reduction as compare to control in nodule weight, size and numbers. This fact becomes clear while observing the nodules growing in the boron free culture, which did not develop extensively. The comparison of the transverse sections of root-nodule area, from nutrient solutions with various boron concentrations showed that in the absence of boron, there was a considerable hypertrophy in cambial cells and a frequent disintegration of phloem and ground tissue along with xylem. The disintegration of the tissue seems to be linked with nodule bacteria. The nodular bacteria are considered to assume a parasitic habit in the absence of boron. (author)

  13. De Novo Assembly of the Pea (Pisum sativum L. Nodule Transcriptome

    Directory of Open Access Journals (Sweden)

    Vladimir A. Zhukov

    2015-01-01

    Full Text Available The large size and complexity of the garden pea (Pisum sativum L. genome hamper its sequencing and the discovery of pea gene resources. Although transcriptome sequencing provides extensive information about expressed genes, some tissue-specific transcripts can only be identified from particular organs under appropriate conditions. In this study, we performed RNA sequencing of polyadenylated transcripts from young pea nodules and root tips on an Illumina GAIIx system, followed by de novo transcriptome assembly using the Trinity program. We obtained more than 58,000 and 37,000 contigs from “Nodules” and “Root Tips” assemblies, respectively. The quality of the assemblies was assessed by comparison with pea expressed sequence tags and transcriptome sequencing project data available from NCBI website. The “Nodules” assembly was compared with the “Root Tips” assembly and with pea transcriptome sequencing data from projects indicating tissue specificity. As a result, approximately 13,000 nodule-specific contigs were found and annotated by alignment to known plant protein-coding sequences and by Gene Ontology searching. Of these, 581 sequences were found to possess full CDSs and could thus be considered as novel nodule-specific transcripts of pea. The information about pea nodule-specific gene sequences can be applied for gene-based markers creation, polymorphism studies, and real-time PCR.

  14. Cloning, overexpression, purification and preliminary crystallographic studies of a mitochondrial type II peroxiredoxin from Pisum sativum

    Energy Technology Data Exchange (ETDEWEB)

    Barranco-Medina, Sergio [Departamento de Bioquímica, Biología Molecular y Celular de Plantas, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, E-18008 Granada (Spain); López-Jaramillo, Francisco Javier, E-mail: fjljara@ugr.es [Instituto de Biotecnología, Campus Fuentenueva, Universidad de Granada, E-18071 Granada (Spain); Bernier-Villamor, Laura [Departamento de Bioquímica, Biología Molecular y Celular de Plantas, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, E-18008 Granada (Spain); Sevilla, Francisca [Departamento de Biología del Estrés y Patología Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, E-30080 Murcia (Spain); Lázaro, Juan-José [Departamento de Bioquímica, Biología Molecular y Celular de Plantas, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, E-18008 Granada (Spain)

    2006-07-01

    The isolation, purification, crystallization and molecular-replacement solution of mitochondrial type II peroxiredoxin from P. sativum is reported. A cDNA encoding an open reading frame of 199 amino acids corresponding to a type II peroxiredoxin from Pisum sativum with its transit peptide was isolated by RT-PCR. The 171-amino-acid mature protein (estimated molecular weight 18.6 kDa) was cloned into the pET3d vector and overexpressed in Escherichia coli. The recombinant protein was purified and crystallized by the hanging-drop vapour-diffusion technique. A full data set (98.2% completeness) was collected using a rotating-anode generator to a resolution of 2.8 Å from a single crystal flash-cooled at 100 K. X-ray data revealed that the protein crystallizes in space group P1, with unit-cell parameters a = 61.88, b = 66.40, c = 77.23 Å, α = 102.90, β = 104.40, γ = 99.07°, and molecular replacement using a theoretical model predicted from the primary structure as a search model confirmed the presence of six molecules in the unit cell as expected from the Matthews coefficient. Refinement of the structure is in progress.

  15. Sink to Source Transition in Tendrils of a Semileafless Mutant, Pisum sativum cv Curly.

    Science.gov (United States)

    Côté, R; Gerrath, J M; Peterson, C A; Grodzinski, B

    1992-12-01

    Sink to source transition parallels loss of thigmotropic capacity in tendrils of a semileafless mutant, Pisum sativum cv Curly. Macroscopic tendril development is subdivided based on thigmotropic capacity. Stage I is the elongation stage and, although the rate of photosynthesis is similar to that of stage II and III tendrils, dark respiration rates are higher in stage I. During stage II, tendrils are thigmotropic and act as a sink. Even though stage II tendrils have CO(2) exchange characteristics similar to those of stage III tendrils, which are coiled, our fluorescein, (14)C-partitioning, and (11)C-translocation experiments suggest that stage I and II tendrils do not export carbon. Only stage III tendrils act as sources of newly fixed carbon. Export from them is blocked by cold, heat girdling of the petiole, or anoxia treatment of the tendrils. A late stage II tendril complex, in which coiling is occurring, may be exporting photoassimilates; however, this phenomenon can be attributed to the fact that the pea leaf is a compound structure and there may be one or more stage III tendrils, no longer thigmotropic, within the tendril complex. Photosynthetic maturity in pea tendrils occurs at stage III and is characterized by the ability of these tendrils to export photoassimilates. PMID:16653179

  16. Study of DC and AC electric field effect on Pisum sativum seeds growth

    Science.gov (United States)

    Mahmood, Bahar; Jaleh, Sojoodi; Yasaman, Yasaie

    2014-07-01

    In this research the effect of electric field on two groups of wet and dry Pisum sativum seeds growth was studied. To generate the required electric field a parallel-plate capacitor with round copper plates of 30 cm diameter was used. The experiments were performed once in fixed exposure duration of 8 min in variable DC electric field of 0.25-1.5 kV/m. The other experiments were performed in variable fields of 50-125 kV/m in fixed exposure duration of 8 min, in two groups of AC and DC electric fields. The experiments were repeated three times. In each experiment 10 seeds were used and there was a sham exposed group for comparison, too. After application of electric field, the seeds were kept for six days in the same growth chamber with the temperature of 25 ± 1 °C and 12 h light/12 h darkness. On the 6th day length of stems and height of roots were measured. After doing statistical analysis, in low intensities of DC electric field, the highest significant increase of mean growth (The average of stem length and the height of roots) was seen in 1.5 kV/m in wet seeds. In high intensities of DC and AC electric fields, the highest significant increase of mean growth was seen in AC electric field of 100 kV/m in wet seeds.

  17. Determination of the genotoxic effects of Trigonella foenum graecum L. extracts in stored Pisum sativum seeds

    Directory of Open Access Journals (Sweden)

    Fawzia, I. Mohamed

    2012-07-01

    Full Text Available This study was carried out to study the effect of Trigonella foenum graecum L extracts on mitotic, meiotic and cell cycle parameters in stored Pisum sativum seeds. The Trigonella foenum extracts induced a marked decrease in the mitotic index accompanied with considerable percentage of chromosomal aberrations. These abnormalities include stickiness, disturbed chromosomes, bridges and lagging chromosome. Cytophotometric measurements showed inhibition of cells in the Go/G1 phase at the expense of other phases of cell cycle (S-phase, G2-phase. The percentage of cells having 2C DNA content decreased gradually with increasing the concentrations, while those having 4C DNA increased. Trigonella foenum extracts not affected on PMCs. Of P. sativum plant after the seeds treated with 0.5-1% and storage for three months but, significant percentage of chromosome abnormalities observed in the PMCs of the plants treated with 2% Trigonella foenum extracts and storage for three months. Also, after storage for six months all treatments have significant effect on abnormalities of PMCs. In all the treatment, various abnormal cells were observed in mitotic and meiotic division. Aberrant cells observed according to concentration and time of storage of Trigonella foenum extracts.

  18. Purification and properties of asparaginase from the testa of immature seeds of pea (Pisum sativum L.

    Directory of Open Access Journals (Sweden)

    Chagas Eliana P.

    2001-01-01

    Full Text Available A K+-dependent asparaginase (E.C. 3.5.1.1. was purified 1328-fold from the testas of immature pea seeds (Pisum sativum L., var. Bolero and characterized. Antibodies raised against purified asparaginase cross-reacted with the putative asparaginase band in Western blot analyses of semi-purified extracts. However, for crude extracts of pea testas, a cross-reaction was obtained with at least four protein bands, one of which was asparaginase protein. Affinity-purified antibodies to the four strongest bands of crude extracts were fairly specific for the bands from which they were purified, suggesting a mixture of specific antibodies. The Mr of asparaginase was 69,000 by Sephacryl S200 chromatography and also by mobility on native PAGE relative to BSA. There was no evidence for dissociation into subunits on SDS-PAGE, suggesting a monomeric protein of Mr 69,000. Other properties include an apparent Km of 2.4 mM, pI between 4.5 and 5, and competitive inhibition by aspartate and glycine.

  19. Nutritional assessment in vitro and in vivo of raw and extruded peas (Pisum sativum L.).

    Science.gov (United States)

    Alonso, R; Grant, G; Dewey, P; Marzo, F

    2000-06-01

    The effects of extrusion cooking on the nutritional properties of Pisum sativum L. have been evaluated in vitro and in vivo. The treatment greatly elevated protein and starch digestibility in vitro. Also, the amounts of intact starch diminished while total free sugars increased. In addition, the levels of antinutritional factors, such as protease inhibitors and lectins, were greatly decreased. Concentrations of methionine and cystine were low in raw peas and were further reduced by extrusion treatment. The nutritional performance of rats fed extruded pea diets for 15 days was no better than that of rats given raw pea diet. This was due to the overriding effects of amino acid deficiencies in the diets. Weight gains by rats fed extruded pea diets supplemented with amino acids were, however, much higher than those achieved by rats fed supplemented raw pea diets. Food transformation index and protein efficiency ratio values were also greatly improved. Extrusion treatment did therefore significantly improve the nutritional quality of peas. PMID:10888538

  20. Effect of Pisum sativum as protein supplement on buffalo milk production

    Directory of Open Access Journals (Sweden)

    C. Grassi

    2010-02-01

    Full Text Available A study was carried out at an organic buffalo dairy farm in order to investigate the effect of feeding protein peas (Pisum sativum L. as an alternative protein source for buffalo cow diets. Two concentrates were formulated to contain (as fed basis either 350 g/kg of soybean cake (SC or 450 g/kg of peas (PC as the main protein sources. The two concentrates were formulated to be almost isonitrogenous (on average crude protein 240 g/kg DM. Two groups of 10 buffalo cows were used in a 100-day lactation study (from 10 days in milk onwards. Cows were blocked into two groups according to lactation number and previous milk yield and were assigned to one of two dietary treatments: control group was offered in the milking parlour 3 kg of SC, while treatment group was offered the same quantity of PC. All cows were fed a total mixed ration containing 3 kg of SC. Daily milk yield was not affected by treatment, as well as, milk fat and protein percentages, somatic cell count, urea content and fatty acid composition.

  1. Pb2+ exposure induced microsatellite instability in Pisum sativum in a locus related with glutamine metabolism.

    Science.gov (United States)

    Rodriguez, E; Azevedo, R; Moreira, H; Souto, L; Santos, Conceição

    2013-01-01

    Lead (Pb) is a toxic element, but its putative mutagenic effects in plant cells, using molecular markers, remain to unveil. To evaluate if Pb induces mutagenicity, Pisum sativum L. seedlings were exposed to Pb(2+) (up to 2000 mg L(-1)) for 28 days and the instability of microsatellites (or Simple Sequence Repeats, SSR) was analyzed in leaves and roots. The analysis of eight selected microsatellites (SSR1-SSR8) demonstrated that only at the highest dosage microsatellite instability (MSI) occurred, at a frequency of 4.2%. Changes were detected in one microsatellite (SSR6) that is inserted in the locus for glutamine synthetase. SSR6 products of roots exposed to the highest concentration of Pb were 3 bp larger than those of the control. Our data demonstrate that: (a) SSR technique is sensitive to detect Pb-induced mutagenicity in plants. MSI instability is Pb dose dependent and organ dependent (roots are more sensitive); (b) the Pb-sensitive SSR6 is inserted in the glutamine synthetase locus, with still unknown relation with functional changes of this enzyme; (c) Pb levels inducing MSI are much above the maximum admitted levels in some European Union countries for agricultural purpose waters. In conclusion, we propose here the potential use of SSR to evaluate Pb(2+)-induced mutagenicity, in combination with other genetic markers.

  2. Cloning, overexpression, purification and preliminary crystallographic studies of a mitochondrial type II peroxiredoxin from Pisum sativum

    International Nuclear Information System (INIS)

    The isolation, purification, crystallization and molecular-replacement solution of mitochondrial type II peroxiredoxin from P. sativum is reported. A cDNA encoding an open reading frame of 199 amino acids corresponding to a type II peroxiredoxin from Pisum sativum with its transit peptide was isolated by RT-PCR. The 171-amino-acid mature protein (estimated molecular weight 18.6 kDa) was cloned into the pET3d vector and overexpressed in Escherichia coli. The recombinant protein was purified and crystallized by the hanging-drop vapour-diffusion technique. A full data set (98.2% completeness) was collected using a rotating-anode generator to a resolution of 2.8 Å from a single crystal flash-cooled at 100 K. X-ray data revealed that the protein crystallizes in space group P1, with unit-cell parameters a = 61.88, b = 66.40, c = 77.23 Å, α = 102.90, β = 104.40, γ = 99.07°, and molecular replacement using a theoretical model predicted from the primary structure as a search model confirmed the presence of six molecules in the unit cell as expected from the Matthews coefficient. Refinement of the structure is in progress

  3. Comportement agronomique d'une collection de pois (Pisum sativum L

    Directory of Open Access Journals (Sweden)

    Bouslama, M.

    2007-01-01

    Full Text Available Agronomical Behaviour of a Pea Collection (Pisum sativum L.. This experience was achieved under greenhouse conditions. Twelve genotypes of pea were used (Asgrow, Jumbo, Lincoln, Merveille de Kelvedon, Purser, Rajai Torpe, Snajor Kosep, Korai,Wando, Rondo, local genotype, Major Kosep Korai and Surgevil. They were cultivated on peat during 5.5 months (from October to April. Some agronomical parameters were studied: resistance to diseases, (Powdery-mildew, mildew, top yellow virus, anthracnose, browning, fresh matter, number of branches/plant, number of flowers/plant, number of pods/ plant and the yield of grains /plant. Results showed that only the genotype Purser is resistant to all diseases and Surgevil is sensitive only to the Top Yellow virus. The local genotype is sensitive to three frequent diseases (Powdery-mildew, mildew and Anthracnose. With regard to vegetative growth, the highest yield of fresh matter do not contribute towards a high fertility rate. In fact, only the genotypes having a weak yield of fresh matter (Snajor Kosep Korai, Asgrow, Major Kosep Korai, Rajai Torpe and Purser have the most important rate of fertility (> 30%. Within this group, the most important yield (> 9 g/plant is a result of high: number of pods/plant (7.5 to 21.6 and of grains/pod (2.8 to 4.92. Finally, genotype Purser should be retained for farmers and programs of genetic amelioration for its resistance to diseases and agronomical performances.

  4. Studies on antioxidative enzymes induced by cadmium in pea plants (Pisum sativum).

    Science.gov (United States)

    Pandey, Nalini; Singh, Gaurav Kumar

    2012-03-01

    Pea plants (Pisum sativum cv. Swati) exposed to different concentration of cadmium (50,100, 200 microM Cd) under controlled glass house conditions were quantified for different physiological parameters and antioxidative enzymes. In pea plants, Cd produced a significant inhibition of growth and induced chlorosis, marginal yellowing and necrosis in young leaves, the effect being most pronounced at 200 microM Cd supply. An alteration in the activated oxygen metabolism of pea plants were also detected as evidenced by an increase in concentration of H2O2 and TBARS along with decrease in the chlorophyll and carotenoid concentration in leaves. Cadmium toxicity induced an increase in non-protein thiol, ascorbate, proline and cysteine concentration. A significant increment in the activity of SOD, APX and GR, and a decrease in CAT was observed as a result of Cd treatment. The enhanced activity of SOD and inhibition of CAT and POD produces a high build up of H2O2 which appears to be the main cause of oxidative stress due to Cd toxicity in pea plants.

  5. Evaluation of genetic divergence and heritability in pea (Pisum sativum L.

    Directory of Open Access Journals (Sweden)

    Natalia Georgieva

    2016-04-01

    Full Text Available An experiment on genetic evaluation of five genotypes of forage pea (Glyans, Svit, Kamerton, Modus, Pleven 4 was conducted during 2012-2014 period. Analysis of variance showed significant differences among genotypes for the traits pod width, seeds per plant, seed weight per plant and 1000 seed weight. The estimates of genetic parameters of five varieties of Pisum sativum L. indicated a good amount of genetic variation in the experimental materials under investigation. Moderate phenotypic and genotypic coefficients of variation were observed for most of traits except pod length and pod width. For the traits studied seeds per plant, seed weight per plant and plant height were found high heritability along with high genetic gain indicating preponderance of additive effects. Therefore, selection programme based on these characters would be more effective in improving yield parameters of forage pea. The seed yield was positively and significantly correlated with 1000 seed weight and pod stem, which suggested the possibilities of improving seed yield by simultaneous improvement of these traits.

  6. Changes in free polyamines and related enzymes during stipule and pod wall development in Pisum sativum.

    Science.gov (United States)

    Chattopadhyay, Soumen; Lahiri, Kajari; Bharati, Ghosh

    2002-08-01

    Level of free polyamines, their key metabolic enzymes, and other features related to ageing were examined during stipule and pod wall development in pea (Pisum sativum). Free polyamine titre (per unit fresh mass) in both the organs, the specific activities of arginine decarboxylase and ornithine decarboxylase in the pod wall, gradually decreased with maturation. In stipule, these enzymes attained peak activity at 15 days after pod emergence and declined thereafter. Ornithine decarboxylase activity was greater in pod wall than in stipule; while, arginine decarboxylase activity was higher in stipule. Activity of degradative enzyme diamine oxidase increased with the onset of senescence in both the organs. Chlorophyll and electrical conductance had a inverse relationship throughout the experimental period, whereas, the chlorophyll content was directly related with polyamine levels in both stipule and pod wall during aging. On the other hand, protein and RNA contents were positively correlated with free polyamines throughout the test period in stipule, but in the pod wall this was true only for the later stages of development.

  7. Role of LLD, a new locus for leaflet/pinna morphogenesis in Pisum sativum

    Indian Academy of Sciences (India)

    Seema Prajapati; Sushil Kumar

    2001-12-01

    Properties of a mutant at the LLD (LEAF-LET DEVELOPMENT) locus in pea Pisum sativum L. are reported in this paper. Plants homozygous for the Mendelian recessive mutation lld bear leaves in which a few to many leaflets are incompletely developed. Opposite pinnae of rachis nodes often formed fused incompletely developed leaflets. The lld mutation was observed to abort pinna development at almost all morphogenetic stages. The lld mutation demonstrated high penetrance and low expressivity. The phenotypes of lld plants in tl, tac, tl tac, tl af and tl af tac backgrounds suggested that LLD function is involved in the separation of lateral adjacent blastozones differentiated on primary, secondary and tertiary rachides and lamina development in leaflets. The aborted development of tendrils and leaflets in lld mutants was related to deficiency in vascular tissue growth. The morphological and anatomical features of the leaflets formed on a tl lld double mutant permitted a model of basipetal leaflet development. The key steps of leaflet morphogenesis include origin of the lamina by splitting of a radially symmetrical growing pinna having abaxial outer surface, opposite to the vascular cylinder, through an invaginational groove, differentiation of adaxial surface along the outer boundary of split tissue in the groove and expansion of the lamina ridges so formed into lamina spans.

  8. Evidence that the mature leaves contribute auxin to the immature tissues of pea (Pisum sativum L.).

    Science.gov (United States)

    Jager, Corinne E; Symons, Gregory M; Glancy, Naomi E; Reid, James B; Ross, John J

    2007-07-01

    In plants such as the garden pea (Pisum sativum L.), it is widely thought that the auxin indole-3-acetic acid (IAA) is synthesised mainly in the immature tissues of the apical bud and then transported basipetally to other parts of the plant. Consistent with this belief are results showing that removal of the apical bud markedly reduces the IAA content in the stem. However, it has also been suggested that the mature leaves may synthesise substantial amounts of IAA, which enters the basipetal transport stream after being transported to the shoot apex in the phloem (Cambridge and Morris in Planta 99:583-588, 1996). To examine this theory, we defoliated pea plants and measured the effect on IAA content in the remaining shoot tissues. IAA levels were reduced in the internodes, and to a lesser extent in the apical bud, after defoliation, suggesting that mature leaves are indeed an important source of auxin for the shoot. Consistent with this idea, we have demonstrated that mature, fully expanded leaves are capable of de novo IAA synthesis. Furthermore, we report evidence for the presence of IAA in the phloem sap of pea. Together these results support those of Cambridge and Morris, suggesting that mature leaves are a source of the IAA in the basipetal transport stream. PMID:17308928

  9. Auxin effects on in vitro and in vivo protein phosphorylation in pea. [Pisum sativum

    Energy Technology Data Exchange (ETDEWEB)

    Gallagher, S.R.; Ray, P.M.

    1987-04-01

    Terminal 8mm sections from the third internode of dark grown 7 day old Pisum sativum cv Alaska seedlings were separated into membrane and soluble fractions. SDS gradient PAGE identified approximately 50 in vivo phosphorylated proteins and proved superior to 2-D SDS PAGE in terms of resolution and repeatability. Addition of indoleacetic acid (IAA), fusicoccin, or 2,4 dichlorophenoxyacetic acid to membranes resulted in no detectable change in the number or phosphorylation level of the labeled proteins during in vitro phosphorylation in the presence of submicromolar concentrations of calcium. Similar results were obtained with soluble proteins. In the absence of calcium, the level of in vitro protein phosphorylation was much less, but not auxin effects could be identified. Furthermore, treatment of the sections with IAA in vivo followed by cell fractionation and in vitro phosphorylation failed to identify auxin responsive proteins. Lastly, when sections were labeled with /sup 32/P inorganic phosphate in the presence of 17 uM IAA, no auxin specific changes were found in the level of phosphorylation or in the number of phosphorylated proteins. Auxin effects on phosphorylation are thus slight or below their detection limit.

  10. Genetic interaction and mapping studies on the leaflet development (lld) mutant in Pisum sativum.

    Science.gov (United States)

    Kumar, Sushil; Mishra, Raghvendra Kumar; Kumar, Arvind; Chaudhary, Swati; Sharma, Vishakha; Kumari, Renu

    2012-01-01

    In Pisum sativum, the completely penetrant leaflet development (lld) mutation is known to sporadically abort pinnae suborgans in the unipinnate compound leaf. Here, the frequency and morphology of abortion was studied in each of the leaf suborgans in 36 genotypes and in presence of auxin and gibberellin, and their antagonists. Various lld genotypes were constructed by multifariously recombining lld with a coch homeotic stipule mutation and with af, ins, mare, mfp, tl and uni-tac leaf morphology mutations. It was observed that the suborgans at all levels of pinna subdivisions underwent lld-led abortion events at different stages of development. As in leafblades, lld aborted the pinnae in leaf-like compound coch stipules. The lld mutation interacted with mfp synergistically and with other leaf mutations additively. The rod-shaped and trumpet-shaped aborted pea leaf suborgans mimicked the phenotype of aborted leaves in HD-ZIP-III-deficient Arabidopsis thaliana mutants. Suborganwise aborted morphologies in lld gnotypes were in agreement with basipetal differentiation of leaflets and acropetal differentiation in tendrils. Altogether, the observations suggested that LLD was the master regulator of pinna development. On the basis of molecular markers found linked to lld, its locus was positioned on the linkage group III of the P. sativum genetic map. PMID:23271018

  11. Purification and Characterization of a Lectin from Green Split Peas (Pisum sativum).

    Science.gov (United States)

    Ng, Tzi Bun; Chan, Yau Sang; Ng, Charlene Cheuk Wing; Wong, Jack Ho

    2015-11-01

    Lectins have captured the attention of a large number of researchers on account of their various exploitable activities, including antitumor, immunomodulatory, antifungal, as well as HIV reverse transcriptase inhibitory activities. A mannose/glucose-specific lectin was isolated from green split peas (a variety of Pisum sativum) and characterized. The purification step involved anion-exchange chromatography on a DEAE-cellulose column, cation-exchange chromatography on an SP-Sepharose column, and gel filtration by fast protein liquid chromatography (FPLC) on Superdex 200. The purified lectin had a native molecular mass of around 50 kDa as determined by size exclusion chromatography. It appeared as a heterotetramer, composed of two distinct polypeptide bands with a molecular mass of 6 and 19 kDa, respectively, in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The N-terminal sequence of green split pea lectin shows some degree of homology compared to lectins from other legume species. Its hemagglutinating activity was inhibited by glucose, mannose, and sucrose, and attenuated at pH values higher than 12 or lower than 3. Hemagglutinating activity was preserved at temperatures lower than 80 °C. The lectin did not show antifungal activity toward fungi including Fusarium oxysporum, Botrytis cinerea, and Mycosphaerella arachidicola. Green split pea lectin showed a mitogenic effect toward murine splenocytes and could inhibit the activity of HIV-1 reverse transcriptase.

  12. Genetic interaction and mapping studies on the leaflet development (lld) mutant in Pisum sativum

    Indian Academy of Sciences (India)

    Sushil Kumar; Raghvendra Kumar Mishra; Arvind Kumar; Swati Chaudhary; Vishakha Sharma; Renu Kumari

    2012-12-01

    In Pisum sativum, the completely penetrant leaflet development (lld) mutation is known to sporadically abort pinnae suborgans in the unipinnate compound leaf. Here, the frequency and morphology of abortion was studied in each of the leaf suborgans in 36 genotypes and in presence of auxin and gibberellin, and their antagonists. Various lld genotypes were constructed by multifariously recombining lld with a coch homeotic stipule mutation and with af, ins, mare, mfp, tl and uni-tac leaf morphology mutations. It was observed that the suborgans at all levels of pinna subdivisions underwent lld-led abortion events at different stages of development. As in leafblades, lld aborted the pinnae in leaf-like compound coch stipules. The lld mutation interacted with mfp synergistically and with other leaf mutations additively. The rod-shaped and trumpet-shaped aborted pea leaf suborgans mimicked the phenotype of aborted leaves in HD-ZIP-III-deficient Arabidopsis thaliana mutants. Suborganwise aborted morphologies in lld gnotypes were in agreement with basipetal differentiation of leaflets and acropetal differentiation in tendrils. Altogether, the observations suggested that LLD was the master regulator of pinna development. On the basis of molecular markers found linked to lld, its locus was positioned on the linkage group III of the P. sativum genetic map.

  13. Phytochrome regulation of gibberellin metabolism in shoots of dwarf Pisum sativum L

    International Nuclear Information System (INIS)

    To study the effect of light on the recessive dwarfing allele, le, of Pisum sativum L., etiolated, paclobutrazol treated LeLe (cv. Alaska) and lele (cv. Progress) pea seedlings were transferred to different light regimes. The growth response of both genotypes to applications of GA1, GA20, and steviol was measured over 48 hours using position transducers. Both genotypes responded to GA1 under red irradiation and in darkness. The LeLe plants grew in response to steviol and GA20 under red irradiation and in darkness. The lele plants responded to steviol and GA20 in darkness, but showed a much smaller response when red irradiated. The red effect on lele plants was reversible by far-red irradiation. [3H]GA20 was applied to nana pea seedlings, homozygous for le, grown under different light regimes. Radioactive metabolites were later extracted from the shoots of the treated plants. Both the free acid and conjugate pools were analyzed by reversed phase HPLC, and some radioactive metabolites were tentatively identified by comparing their retention times to those of authentic [3H]GAs

  14. Bacterial symbionts, Buchnera, and starvation on wing dimorphism in English grain aphid, Sitobion avenae (F.) (Homoptera: Aphididae)

    Science.gov (United States)

    Wing dimorphism in aphids can be affected by multiple cues including both biotic (nutrition, crowding, interspecific interactions, the presence of natural enemies, maternal and transgenerational effects, and alarm pheromone) and abiotic factors (temperature, humidity, and photoperiod). Virtually al...

  15. Tritrophic associations and taxonomic notes on Lysiphlebus fabarum (Marshall (Hymenoptera: Braconidae: Aphidiinae, a keystone aphid parasitoid in Iran

    Directory of Open Access Journals (Sweden)

    Rakhshani Ehsan

    2013-01-01

    Full Text Available An investigation of host associations, distribution and types of reproduction (sexual, asexual of Lysiphlebus fabarum (Marshall across 20 provinces of Iran during 2006-2011 was undertaken. The parasitoid was reared from three groups of host aphids belonging to genera Aphis and Brachycaudus, and occasional host aphid genera. Aphis craccivora Koch was the most frequent host aphid for L. fabarum on various host plants, including economically important crops. The field sex ratio generally favored females, but in some cases, only thelytokous (uniparental populations were found. In those cases, the host was always an Aphis species. Specimens reared from Brachycaudus aphids were all biparental, indicating the presence of a sibling biological species. Overall analysis of diagnostic morphological characters in the forewing indicated intra-specific variability in forewing marginal setae as well as variations in length of the R1 vein. [Projekat Ministarstva nauke Republike Srbije, br. 43001

  16. Aphid effects on rhizosphere microorganisms and microfauna depend more on barley growth phase than on soil fertilization

    DEFF Research Database (Denmark)

    Madsen, Mette Vestergård; Strandmark, Lisa Bjørnlund; Christensen, Søren

    2004-01-01

    This paper gives the first reports on aphid effects on rhizosphere organisms as influenced by soil nutrient status and plant development. Barley plants grown in pots fertilized with N but without P (N), with N and P (NP), or not fertilized (0) were sampled in the early growth phase (day 25), 1 week...... before and 1 week after spike emergence. Aphids were added 16 days before sampling was carried out. In a separate experiment belowground respiration was measured on N and NP fertilized plant–soil systems with aphid treatments comparable to the first experiment. Aphids reduced numbers of rhizosphere...... experimental conditions with nematodes being the dominant bacterial grazers at N fertilization and Protozoa in the NP treatment before spike emergence....

  17. Temperature dependent functional response of Diaeretiella rapae (Hymenoptera: Aphidiidae) to the cabbage aphid, Brevicoryne brassicae (Hemiptera: Aphididae)

    DEFF Research Database (Denmark)

    Moayeri, Hamid R. S.; Madadi, Hossein; Pouraskari, Hossein;

    2013-01-01

    Diaeretiella rapae MacIntosh (Hymenoptera: Aphidiidae) is one of the most common and successful parasitoids of the cabbage aphid. The functional response of D. rapae towards cabbage aphids was examined in laboratory studies at three constant temperatures, 17°C, 25°C and 30°C. D. rapae exhibited a....... rapae as a biocontrol agent of Brevicoryne brassicae at different temperatures.......Diaeretiella rapae MacIntosh (Hymenoptera: Aphidiidae) is one of the most common and successful parasitoids of the cabbage aphid. The functional response of D. rapae towards cabbage aphids was examined in laboratory studies at three constant temperatures, 17°C, 25°C and 30°C. D. rapae exhibited...

  18. QTL Mapping by SLAF-seq and Expression Analysis of Candidate Genes for Aphid Resistance in Cucumber.

    Science.gov (United States)

    Liang, Danna; Chen, Minyang; Qi, Xiaohua; Xu, Qiang; Zhou, Fucai; Chen, Xuehao

    2016-01-01

    Cucumber, a very important vegetable crop worldwide, is easily damaged by pests. Aphid is one of the most serious cucumber pests and frequently cause severe damage to commercially produced crops. Understanding the genetic mechanisms underlying pest resistance is important for aphid-resistant cucumber varieties breeding. In this study, two parental cucumber lines, JY30 (aphid susceptible) and EP6392 (aphid resistant), and pools of resistant and susceptible (n = 50 each) plants from 1000 F2 individuals derived from crossing JY30 with EP6392, were used to detect genomic regions associated with aphid resistance in cucumbers. The analysis was performed using specific length amplified fragment sequencing (SLAF-seq), bulked segregant analysis (BSA), and single nucleotide polymorphism index (SNP-index) methods. A main effect QTL (quantitative trait locus) of 0.31 Mb on Chr5, including 43 genes, was identified by association analysis. Sixteen of the 43 genes were identified as potentially associated with aphid resistance through gene annotation analysis. The effect of aphid infestation on the expression of these candidate genes screened by SLAF-seq was investigated in EP6392 plants by qRT-PCR. The results indicated that seven genes including encoding transcription factor MYB59-like (Csa5M641610.1), auxin transport protein BIG-like (Csa5M642140.1), F-box/kelch-repeat protein At5g15710-like (Csa5M642160.1), transcription factor HBP-1a-like (Csa5M642710.1), beta-glucan-binding protein (Csa5M643380.1), endo-1,3(4)-beta-glucanase 1-like (Csa5M643880.1), and proline-rich receptor-like protein kinase PERK10-like (Csa5M643900.1), out of the 16 genes were down regulated after aphid infestation, whereas 5 genes including encoding probable leucine-rich repeat (LRR) receptor-like serine/threonine-protein kinase At5g15730-like (Csa5M642150.1), Stress-induced protein KIN2 (Csa5M643240.1 and Csa5M643260.1), F-box family protein (Csa5M643280.1), F-box/kelch-repeat protein (Csa5M643290

  19. QTL Mapping by SLAF-seq and Expression Analysis of Candidate Genes for Aphid Resistance in Cucumber

    Directory of Open Access Journals (Sweden)

    Danna Liang

    2016-07-01

    Full Text Available Cucumber, a very important vegetable crop worldwide, is easily damaged by pests. Aphid is one of the most serious cucumber pests and frequently cause severe damage to commercially produced crops. Understanding the genetic mechanisms underlying pest resistance is important for aphid-resistant cucumber varieties breeding. In this study, two parental cucumber lines, JY30 (aphid susceptible and EP6392 (aphid resistant, and pools of resistant and susceptible (n = 50 each plants from 1000 F2 individuals derived from crossing JY30 with EP6392, were used to detect genomic regions associated with aphid resistance in cucumbers. The analysis was performed using specific length amplified fragment sequencing (SLAF-seq, bulked segregant analysis (BSA and single nucleotide polymorphism index (SNP-index methods. A main effect QTL (quantitative trait locus of 0.31 Mb on Chr5, including 43 genes, was identified by association analysis. Sixteen of the 43 genes were identified as potentially associated with aphid resistance through gene annotation analysis. The effect of aphid infestation on the expression of these candidate genes screened by SLAF-seq was investigated in EP6392 plants by qRT-PCR. The results indicated that 7 genes including encoding transcription factor MYB59-like (Csa5M641610.1, auxin transport protein BIG-like (Csa5M642140.1, F-box/kelch-repeat protein At5g15710-like (Csa5M642160.1, transcription factor HBP-1a-like (Csa5M642710.1, beta-glucan-binding protein (Csa5M643380.1, endo-1,3(4-beta-glucanase 1-like (Csa5M643880.1, and proline-rich receptor-like protein kinase PERK10-like (Csa5M643900.1, out of the 16 genes were down regulated after aphid infestation, whereas 5 genes including encoding probable leucine-rich repeat receptor-like serine/threonine-protein kinase At5g15730-like (Csa5M642150.1, Stress-induced protein KIN2 (Csa5M643240.1 and Csa5M643260.1, F-box family protein (Csa5M643280.1, F-box/kelch-repeat protein (Csa5M643290.1, were up

  20. A reinvestigation provides no evidence for sugar residues on structural proteins of poleroviruses and argues against a role for glycosylation of virus structural proteins in aphid transmission.

    Science.gov (United States)

    Revollon, S; Strub, J M; Fitchette, A-C; Wiss, L; Gomord, V; Van Dorsselaer, A; Brault, V

    2010-07-01

    Poleroviruses are strictly transmitted by aphids. Glycosylation of Turnip yellows virus (TuYV) was previously reported and this modification was supposed to be required for aphid transmission. Using different approaches based on (i) a lectin-binding assay, (ii) use of specific complex glycan antibodies and (iii) mass spectrometry, we found no evidence that the structural proteins of TuYV and Cucurbit aphid-borne yellow virus (CABYV) carry glycan residues. Moreover, mutation of each of the four potential N-glycosylation sites of the structural protein sequences of CABYV indicated that, unless more than one site on the structural protein is glycosylated, N-glycosylation is not involved in aphid transmission. These results did not corroborate the previous hypothesis for the role of glycosylation in aphid transmission. They, however, revealed the presence of a glycosylated plant protein in purified polerovirus suspensions, whose function in aphid transmission should be further investigated. PMID:20416918

  1. Evolutionary conservation of candidate osmoregulation genes in plant phloem sap-feeding insects.

    Science.gov (United States)

    Jing, X; White, T A; Luan, J; Jiao, C; Fei, Z; Douglas, A E

    2016-06-01

    The high osmotic pressure generated by sugars in plant phloem sap is reduced in phloem-feeding aphids by sugar transformations and facilitated water flux in the gut. The genes mediating these osmoregulatory functions have been identified and validated empirically in the pea aphid Acyrthosiphon pisum: sucrase 1 (SUC1), a sucrase in glycoside hydrolase family 13 (GH13), and aquaporin 1 (AQP1), a member of the Drosophila integral protein (DRIP) family of aquaporins. Here, we describe molecular analysis of GH13 and AQP genes in phloem-feeding representatives of the four phloem-feeding groups: aphids (Myzus persicae), coccids (Planococcus citri), psyllids (Diaphorina citri, Bactericera cockerelli) and whiteflies (Bemisia tabaci MEAM1 and MED). A single candidate GH13-SUC gene and DRIP-AQP gene were identified in the genome/transcriptome of most insects tested by the criteria of sequence motif and gene expression in the gut. Exceptionally, the psyllid Ba. cockerelli transcriptome included a gut-expressed Pyrocoelia rufa integral protein (PRIP)-AQP, but has no DRIP-AQP transcripts, suggesting that PRIP-AQP is recruited for osmoregulatory function in this insect. This study indicates that phylogenetically related SUC and AQP genes may generally mediate osmoregulatory functions in these diverse phloem-feeding insects, and provides candidate genes for empirical validation and development as targets for osmotic disruption of pest species. PMID:26896054

  2. Comparative studies on uptake and translocation of labelled dimethoate and methamidophos by means of systemic and local bibitors

    Energy Technology Data Exchange (ETDEWEB)

    Richter, S. (Karl-Marx-Universitaet, Leipzig (German Democratic Republic)); Dedek, W. (Akademie der Wissenschaften der DDR, Leipzig. Forschungsstelle fuer Chemische Toxikologie)

    1983-01-01

    Uptake, mobility and translocation of /sup 14/C-dimethoate and /sup 32/P-methamidophos in Vicia faba L. and Oryza sativa L. were studied by means of pea aphid (Acyrthosiphon pisum Harris), red spider mite (Tetranychus urticae Koch) and rice cicada (Sogatodes orizicola Muir). A relationship was found to exist between the uptake of active ingredients and the individual developmental stages. Both ingredients are rapidly taken up through the roots and translocated throughout the plant, the rate of incorporation being higher with mites - due to the higher share of active ingredients in their cells - than with aphids. Tests without allowing time for exposition are possible and provide direct information on the rate of uptake. Both dimethoate and methamidophos penetrate into the leaf tissue. The phloem is loaded somewhat more slowly, the rate of load being more favourable with dimethoate. Acropetal and basipetal translocation proceed accordingly. However, the two active ingredients under review are not transported in insecticidal or acaricidal concentrations. Unlike dimethoate, the insecticidal action of methamidophos in field bean persists for 20 days or more. Studies on the mobility of dimethoate in rice plants point to a high apoplastic translocation in the treated leaf and to a somewhat retarded acropetal translocation in insecticidal concentrations. These results show that bioassays may be carried out not only with aphids but also with spider mites and cicades to demonstrate the mobility of chemical agents in plants.

  3. Spatial organization of the glucosinolate-myrosinase system in brassica specialist aphids is similar to that of the host plant.

    OpenAIRE

    Bridges, Matthew; Jones, Alexandra M. E.; Bones, Atle M.; Hodgson, Chris; Cole, Rosemary; Bartlet, Elspeth; Wallsgrove, Roger; Karapapa, Vassiliki K; Watts, Nigel; Rossiter, John T.

    2002-01-01

    Secondary metabolites are important in plant defence against pests and diseases. Similarly, insects can use plant secondary metabolites in defence and, in some cases, synthesize their own products. The paper describes how two specialist brassica feeders, Brevicoryne brassicae (cabbage aphid) and Lipaphis erysimi (turnip aphid) can sequester glucosinolates (thioglucosides) from their host plants, yet avoid the generation of toxic degradation products by compartmentalizing myrosinase (thiogluco...

  4. Deciphering the role of NADPH oxidase in complex interactions between maize (Zea mays L.) genotypes and cereal aphids.

    Science.gov (United States)

    Sytykiewicz, Hubert

    2016-07-22

    Plant NADPH oxidases (NOXs) encompass a group of membrane-bound enzymes participating in formation of reactive oxygen species (ROS) under physiological conditions as well as in response to environmental stressors. The purpose of the survey was to unveil the role of NADPH oxidase in pro-oxidative responses of maize (Zea mays L.) seedling leaves exposed to cereal aphids' infestation. The impact of apteral females of bird cherry-oat aphid (Rhopalosiphum padi L.) and grain aphid (Sitobion avenae F.) feeding on expression levels of all four NADPH oxidase genes (rbohA, rbohB, rbohC, rbohD) and total activity of NOX enzyme in maize plants were investigated. In addition, inhibitory effect of diphenylene iodonium (DPI) pre-treatment on NOX activity and hydrogen peroxide content in aphid-stressed maize seedlings was studied. Leaf infestation biotests were accomplished on 14-day-old seedlings representing two aphid-resistant varieties (Ambrozja and Waza) and two aphid-susceptible ones (Tasty Sweet and Złota Karłowa). Insects' attack led to profound upregulation of rbohA and rbohD genes in tested host plants, lower elevations were noted in level of rbohB mRNA, whereas abundance of rbohC transcript was not significantly altered. It was uncovered aphid-induced enhancement of NOX activity in examined plants. Higher increases in expression of all investigated rboh genes and activity of NADPH oxidase occurred in tissues of more resistant maize cultivars than in susceptible ones. Furthermore, DPI treatment resulted in strong reduction of NOX activity and H2O2 accumulation in aphid-infested Z. mays plants, thus evidencing circumstantial role of the enzyme in insect-elicited ROS generation. PMID:27178208

  5. Up-regulation of abscisic acid signaling pathway facilitates aphid xylem absorption and osmoregulation under drought stress.

    Science.gov (United States)

    Guo, Huijuan; Sun, Yucheng; Peng, Xinhong; Wang, Qinyang; Harris, Marvin; Ge, Feng

    2016-02-01

    The activation of the abscisic acid (ABA) signaling pathway reduces water loss from plants challenged by drought stress. The effect of drought-induced ABA signaling on the defense and nutrition allocation of plants is largely unknown. We postulated that these changes can affect herbivorous insects. We studied the effects of drought on different feeding stages of pea aphids in the wild-type A17 of Medicago truncatula and ABA signaling pathway mutant sta-1. We examined the impact of drought on plant water status, induced plant defense signaling via the abscisic acid (ABA), jasmonic acid (JA), and salicylic acid (SA) pathways, and on the host nutritional quality in terms of leaf free amino acid content. During the penetration phase of aphid feeding, drought decreased epidermis/mesophyll resistance but increased mesophyll/phloem resistance of A17 but not sta-1 plants. Quantification of transcripts associated with ABA, JA and SA signaling indicated that the drought-induced up-regulation of ABA signaling decreased the SA-dependent defense but increased the JA-dependent defense in A17 plants. During the phloem-feeding phase, drought had little effect on the amino acid concentrations and the associated aphid phloem-feeding parameters in both plant genotypes. In the xylem absorption stage, drought decreased xylem absorption time of aphids in both genotypes because of decreased water potential. Nevertheless, the activation of the ABA signaling pathway increased water-use efficiency of A17 plants by decreasing the stomatal aperture and transpiration rate. In contrast, the water potential of sta-1 plants (unable to close stomata) was too low to support xylem absorption activity of aphids; the aphids on sta-1 plants had the highest hemolymph osmolarity and lowest abundance under drought conditions. Taken together this study illustrates the significance of cross-talk between biotic-abiotic signaling pathways in plant-aphid interaction, and reveals the mechanisms leading to alter

  6. Effects of autumn kaolin treatments on the rosy apple aphid Dysaphis planaginea (Pass.) and possible modes of action.

    OpenAIRE

    Bürgel, K.; Daniel, Claudia; Wyss, Eric

    2005-01-01

    Autumn applications of the repellent processed-kaolin particle film (Surround ® WP) might be an alternative to the insecticides commonly used in spring to control the rosy apple aphid, Dysaphis plantaginea (Pass.) (Hom., Aphididae). To assess the mode of action and the impact of kaolin on autumn forms of D. plantaginea, trials were conducted in field cages and in open-fields in autumn 2003. Choice and no-choice experiments in field cages showed that winged aphids landed in significantly lower...

  7. Development and characterization of Brassica juncea – fruticulosa introgression lines exhibiting resistance to mustard aphid (Lipaphis erysimi Kalt

    Directory of Open Access Journals (Sweden)

    Atri Chhaya

    2012-11-01

    Full Text Available Abstract Background Mustard aphid is a major pest of Brassica oilseeds. No source for aphid resistance is presently available in Brassica juncea . A wild crucifer, Brassica fruticulosa is known to be resistant to mustard aphid. An artificially synthesized amphiploid, AD-4 (B. fruticulosa × B. rapa var. brown sarson was developed for use as a bridge species to transfer fruticulosa resistance to B. juncea. Using the selfed backcross we could select a large number of lines with resistance to mustard aphid. This paper reports cytogenetic stability of introgression lines, molecular evidence for alien introgression and their reaction to mustard aphid infestation. Results Majority of introgression lines had expected euploid chromosome number(2n= 36, showed normal meiosis and high pollen grain fertility. Well-distributed and transferable simple-sequence repeats (SSR markers for all the 18 B. juncea chromosomes helped to characterize introgression events. Average proportions of recipient and donor genome in the substitution lines were 49.72 and 35.06%, respectively. Minimum alien parent genome presence (27.29% was observed in the introgression line, Ad3K-280 . Introgressed genotypes also varied for their resistance responses to mustard aphid infestations under artificial release conditions for two continuous seasons. Some of the test genotypes showed consistent resistant reaction. Conclusions B.juncea-fruticulosa introgression set may prove to be a very powerful breeding tool for aphid resistance related QTL/gene discovery and fine mapping of the desired genes/QTLs to facilitate marker assisted transfer of identified gene(s for mustard aphid resistance in the background of commercial mustard genotypes.

  8. Localization, Concentration, and Transmission Efficiency of Banana bunchy top virus in Four Asexual Lineages of Pentalonia aphids

    OpenAIRE

    Alberto Bressan; Shizu Watanabe; April M. Greenwell

    2013-01-01

    Banana bunchy top virus (BBTV) is the most destructive pathogenic virus of banana plants worldwide. The virus is transmitted in a circulative non-propagative manner by the banana aphid, Pentalonia nigronervosa Coquerel. In this work, we examined the localization, accumulation, and transmission efficiency of BBTV in four laboratory-established lineages of Pentalonia aphids derived from four different host plants: taro (Colocasia esculenta), heliconia (Heliconia spp.), red ginger (Alpinia purpu...

  9. Effect of sowing date and straw mulch on virus incidence and aphid infestation in organic faba-beans (Vicia faba L.)

    OpenAIRE

    Saucke, H; Juergens, M.; Döring, Th. F.; Lesemann, D.E.; Fittje, S.; Vetten, H.-J.

    2009-01-01

    The effect of sowing date on aphid infestation and the incidence of aphid-transmitted viruses were investigated in organically managed, small-scale field experiments with two faba bean cultivars over 3 years (2002–04). As an additional factor, strawmulchwas applied in 2 of the 3 years shortly before the start of vector activity in May. Virus incidence was determined using enzyme-linked immunosorbent assay and immunoelectron microscopy. Aphid flight activity was monitored using standard yellow...

  10. Interactions between a luteovirus and the GroEL chaperonin protein of the symbiotic bacterium Buchnera aphidicola of aphids.

    Science.gov (United States)

    Bouvaine, Sophie; Boonham, Neil; Douglas, Angela E

    2011-06-01

    Luteoviruses and poleroviruses are important plant viruses transmitted exclusively by aphids in a circulative manner via the aphid haemolymph. A chaperonin protein, GroEL, synthesized in aphids by a symbiotic bacterium, Buchnera aphidicola, is hypothesized to bind to virus particles in the haemolymph, thereby promoting transmission. To investigate this hypothesis, the GroEL-binding site for barley yellow dwarf virus (BYDV) was determined in vitro, and the abundance of GroEL protein in different aphid tissues was investigated. Virus binding to a peptide library representing the full GroEL molecule revealed a single binding site that coincides with the site that anchors two GroEL rings to form the native GroEL tetradecamer. In the functional form of the GroEL protein, virus binding would compete with the formation of the two GroEL rings. Using a mAb raised against a Buchnera-specific GroEL epitope, GroEL was detected in Buchnera cells by immunoblotting and immunocytochemistry, but not in the aphid haemolymph, fat body or gut. From the prediction here that GroEL-virus interactions are probably severely limited by competition with other GroEL molecules, and the evidence that GroEL is not available to interact with virus particles in vivo, it is concluded that GroEL-virus interactions are unlikely to contribute to virus transmission by aphids. PMID:21346031

  11. Transgenic Expression of a Functional Fragment of Harpin Protein Hpa1 in Wheat Represses English Grain Aphid Infestation

    Institute of Scientific and Technical Information of China (English)

    XU Man-yu; ZHOU Ting; ZHAO Yan-ying; LI Jia-bao; XU Heng; DONG Han-song; ZHANG Chun-ling

    2014-01-01

    The harpin protein Hpa1 produced by the rice bacterial blight pathogen promotes plant growth and induces plant resistance to pathogens and insect pests. The region of 10-42 residues (Hpa110-42) in the Hpa1 sequence is critical as the isolated Hpa110-42 fragment is 1.3-7.5-fold more effective than the full length in inducing plant growth and resistance. Here we report that transgenic expression of Hpa110-42 in wheat induces resistance to English grain aphid, a dominant species of wheat aphids. Hpa110-42-induced resistance is effective to inhibit the aphid behavior in plant preference at the initial colonization stage and repress aphid performances in the reproduction, nymph growth, and instar development on transgenic plants. The resistance characters are correlated with enhanced expression of defense-regulatory genes (EIN2, PP2-A, and GSL10) and consistent with induced expression of defense response genes (Hel, PDF1.2, PR-1b, and PR-2b). As a result, aphid infestations are alleviated in transgenic plants. The level of Hpa110-42-induced resistance in regard to repression of aphid infestations is equivalent to the effect of chemical control provided by an insecticide. These results suggested that the defensive role of Hpa110-42 can be integrated into breeding germplasm of the agriculturally signiifcant crop with a great potential of the agricultural application.

  12. A first record of Cretaceous aphids (Hemiptera, Sternorrhyncha, Aphidomorpha) in Australia, from the Lower Cretaceous Koonwarra Fossil Bed, Victoria.

    Science.gov (United States)

    Martin, Sarah K; Skidmore, Luke I; Stilwell, Jeffrey D

    2016-01-01

    This paper describes the first species of aphid from the Lower Cretaceous Koonwarra Fossil Bed of the Gippsland Basin, southeastern Victoria, Australia. This aphid, herein named Koonwarraphis rotundafrons gen. & sp. nov., is assigned to the cosmopolitan Cretaceous superfamily Tajmyraphidoidea, which has been previously described from the Lebanese, Taimyrian, Canadian, Myanmar (Burmese), and Spanish ambers. Koonwarraphis rotundafrons is the first aphid recorded from the eastern Gondwanan landmass during the Cretaceous, and represents the only tajmyraphidoid preserved as a compression fossil, rather than as an amber inclusion. Due to the nature of the fossil's preservation, Koonwarraphis cannot be firmly placed in any of the described tajmyraphidoid families; however, all observable morphological features suggest that the genus is broadly typical of the superfamily and Cretaceous aphids in general. Koonwarraphis' shortened rostrum, a feature also seen in other tajmyraphidoids, suggests an association with the more herbaceous aspects of the Early Cretaceous Victorian flora. Considering the modern aphid preference for angiosperm plants, it is possible that this aphid was living upon the herbaceous early angiosperms recorded previously from the Koonwarra macrofloral assemblage. PMID:27395744

  13. Temperature-Dependent Fecundity and Life Table of the Fennel Aphid Hyadaphis foeniculi (Passerini (Hemiptera: Aphididae.

    Directory of Open Access Journals (Sweden)

    Francisco S Ramalho

    Full Text Available Hyadaphis foeniculi (Passerini (Hemiptera: Aphididae is a cosmopolitan species and the main pest of fennel in northeastern Brazil. Understanding the relationship between temperature variations and the population growth rates of H. foeniculi is essential to predict the population dynamics of this aphid in the fennel crop. The aim of this study was to measure the effect of constant temperature on the adult prereproductive period and the life table fertility parameters (infinitesimal increase ratio (rm, gross reproduction rate (GRR, net reproduction rate (R0, finite increase ratio (λ, generation time (GT, the time required for the population to double in the number of individuals (DT, and the reproduction value (RVx of the fennel pest H. foeniculi. The values of lx (survival of nymphs at age x increased as the temperature rose from 15 to 28°C and fell at 30°C, whereas mx (number of nymphs produced by each nymph of age x increased from 15 to 25°C and fell at 28 and 30°C. The net reproduction rates (R0 of populations of H. foeniculi increased with temperature and ranged from 1.9 at 15°C to 12.23 at 28°C for each generation. The highest population increase occurred with the apterous aphids at 28°C. The rate of population increase per unit time (rm (day ranged from 0.0033 (15°C to 0.1995 (28°C. The highest values of rm were recorded at temperatures of 28°C and 30°C. The rm values were a good fit to the models tested, with R2 > 0.91 and R2adj > 0.88. The models tested (Davidson, Sharpe and DeMichele modified by Schoolfield et al., Logan et al., Lamb, and Briere et al. were very good fits for the rm values observed, with R2 > 0.91 and R2adj > 0.88. The only exception was the Davidson model. Of the parameters studied, the reproductive capacity was higher in the apterous aphids, with the unique exception of daily fecundity at 28°C, which was higher in the alate aphids of H. foeniculi. Parameters relating to the age-specific fertility table for

  14. Determination of 4-Chloroindole-3-Acetic Acid Methyl Ester in Lathyrus Vicia and Pisum by Gas Chromatography - Mass Spectrometry

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen; Egsgaard, Helge; Larsen, Elfinn

    1980-01-01

    4-Chloroindole-3-acetic acid methyl ester was identified unequivocally in Lathyrus latifolius L., Vicia faba L. and Pisum sativum L. by thin layer chromatography, gas chromatography and mass spectrometry. The gas chromatographic system was able to separate underivatized chloroindole-3-acetic acid...... methyl ester isomers. The quantitative determination of 4-chloroindole-3-acetic acid methyl ester in immature seeds of these three species was performed by gas chromatography – mass spectrometry using deuterium labelled 4-chloro-indole-3-acetic acid methyl ester as an internal standard. P. sativum...

  15. Palladium uptake by Pisum sativum: partitioning and effects on growth and reproduction.

    Science.gov (United States)

    Ronchini, Matteo; Cherchi, Laura; Cantamessa, Simone; Lanfranchi, Marco; Vianelli, Alberto; Gerola, Paolo; Berta, Graziella; Fumagalli, Alessandro

    2015-05-01

    Environmental palladium levels are increasing because of anthropogenic activities. The considerable mobility of the metal, due to solubilisation phenomena, and its known bioavailability may indicate interactions with higher organisms. The aim of the study was to determine the Pd uptake and distribution in the various organs of the higher plant Pisum sativum and the metal-induced effects on its growth and reproduction. P. sativum was grown in vermiculite with a modified Hoagland's solution of nutrients in the presence of Pd at concentrations ranging 0.10-25 mg/L. After 8-10 weeks in a controlled environment room, plants were harvested and dissected to isolate the roots, stems, leaves, pods and peas. The samples were analysed for Pd content using AAS and SEM-EDX. P. sativum absorbed Pd, supplied as K₂PdCl₄, beginning at seed germination and continuing throughout its life. Minimal doses (0.10-1.0 mg Pd/L) severely inhibited pea reproductive processes while showing a peculiar hormetic effect on root development. Pd concentrations ≥1 mg/L induced developmental delay, with late growth resumption, increased leaf biomass (up to 25%) and a 15-20% reduction of root mass. Unsuccessful repeated blossoming efforts led to misshapen pods and no seed production. Photosynthesis was also disrupted. The absorbed Pd (ca. 0.5 % of the supplied metal) was primarily fixed in the root, specifically in the cortex, reaching concentrations up to 200 μg/g. The metal moved through the stem (up to 1 μg/g) to the leaves (2 μg/g) and pods (0.3 μg/g). The presence of Pd in the pea fruits, together with established evidence of environmental Pd accumulation and bioavailability, suggests possible contamination of food plants and propagation in the food chain and must be the cause for concern. PMID:25639246

  16. Long-Term Fungal Inhibition by Pisum sativum Flour Hydrolysate during Storage of Wheat Flour Bread

    Science.gov (United States)

    Lavecchia, Anna; Gramaglia, Valerio; Gobbetti, Marco

    2015-01-01

    In order to identify antifungal compounds from natural sources to be used as ingredients in the bakery industry, water/salt-soluble extracts (WSE) from different legume flour hydrolysates obtained by the use of a fungal protease were assayed against Penicillium roqueforti DPPMAF1. The agar diffusion assays allowed the selection of the pea (Pisum sativum) hydrolysate as the most active. As shown by the hyphal radial growth rate, the WSE had inhibitory activity towards several fungi isolated from bakeries. The MIC of the WSE was 9.0 mg/ml. Fungal inhibition was slightly affected by heating and variations in pH. The antifungal activity was attributed to three native proteins (pea defensins 1 and 2 and a nonspecific lipid transfer protein [nsLTP]) and a mixture of peptides released during hydrolysis. The three proteins have been reported previously as components of the defense system of the plant. Five peptides were purified from WSE and were identified as sequences encrypted in leginsulin A, vicilin, provicilin, and the nsLTP. To confirm antifungal activity, the peptides were chemically synthesized and tested. Freeze-dried WSE were used as ingredients in leavened baked goods. In particular, breads made by the addition of 1.6% (wt/wt) of the extract and fermented by baker's yeast or sourdough were characterized for their main chemical, structural, and sensory features, packed in polyethylene bags, stored at room temperature, and compared to controls prepared without pea hydrolysate. Artificially inoculated slices of a bread containing the WSE did not show contamination by fungi until at least 21 days of storage and behaved like the bread prepared with calcium propionate (0.3%, wt/wt). PMID:25862230

  17. Bean pod mottle virus: a new powerful tool for functional genomics studies in Pisum sativum.

    Science.gov (United States)

    Meziadi, Chouaib; Blanchet, Sophie; Richard, Manon M S; Pilet-Nayel, Marie-Laure; Geffroy, Valérie; Pflieger, Stéphanie

    2016-08-01

    Pea (Pisum sativum L.) is an important legume worldwide. The importance of pea in arable rotations and nutritional value for both human and animal consumption have fostered sustained production and different studies to improve agronomic traits of interest. Moreover, complete sequencing of the pea genome is currently underway and will lead to the identification of a large number of genes potentially associated with important agronomic traits. Because stable genetic transformation is laborious for pea, virus-induced gene silencing (VIGS) appears as a powerful alternative technology for determining the function of unknown genes. In this work, we present a rapid and efficient viral inoculation method using DNA infectious plasmids of Bean pod mottle virus (BPMV)-derived VIGS vector. Six pea genotypes with important genes controlling biotic and/or abiotic stresses were found susceptible to BPMV carrying a GFP reporter gene and showed fluorescence in both shoots and roots. In a second step, we investigated 37 additional pea genotypes and found that 30 were susceptible to BPMV and only 7 were resistant. The capacity of BPMV to induce silencing of endogenes was investigated in the most susceptible genotype using two visual reporter genes: PsPDS and PsKORRIGAN1 (PsKOR1) encoding PHYTOENE DESATURASE and a 1,4-β-D-glucanase, respectively. The features of the 'one-step' BPMV-derived VIGS vector include (i) the ease of rub-inoculation, without any need for biolistic or agro-inoculation procedures, (ii) simple cost-effective procedure and (iii) noninterference of viral symptoms with silencing. These features make BPMV the most adapted VIGS vector in pea to make low- to high-throughput VIGS studies. PMID:26896301

  18. Long-Term Fungal Inhibition by Pisum sativum Flour Hydrolysate during Storage of Wheat Flour Bread.

    Science.gov (United States)

    Rizzello, Carlo Giuseppe; Lavecchia, Anna; Gramaglia, Valerio; Gobbetti, Marco

    2015-06-15

    In order to identify antifungal compounds from natural sources to be used as ingredients in the bakery industry, water/salt-soluble extracts (WSE) from different legume flour hydrolysates obtained by the use of a fungal protease were assayed against Penicillium roqueforti DPPMAF1. The agar diffusion assays allowed the selection of the pea (Pisum sativum) hydrolysate as the most active. As shown by the hyphal radial growth rate, the WSE had inhibitory activity towards several fungi isolated from bakeries. The MIC of the WSE was 9.0 mg/ml. Fungal inhibition was slightly affected by heating and variations in pH. The antifungal activity was attributed to three native proteins (pea defensins 1 and 2 and a nonspecific lipid transfer protein [nsLTP]) and a mixture of peptides released during hydrolysis. The three proteins have been reported previously as components of the defense system of the plant. Five peptides were purified from WSE and were identified as sequences encrypted in leginsulin A, vicilin, provicilin, and the nsLTP. To confirm antifungal activity, the peptides were chemically synthesized and tested. Freeze-dried WSE were used as ingredients in leavened baked goods. In particular, breads made by the addition of 1.6% (wt/wt) of the extract and fermented by baker's yeast or sourdough were characterized for their main chemical, structural, and sensory features, packed in polyethylene bags, stored at room temperature, and compared to controls prepared without pea hydrolysate. Artificially inoculated slices of a bread containing the WSE did not show contamination by fungi until at least 21 days of storage and behaved like the bread prepared with calcium propionate (0.3%, wt/wt). PMID:25862230

  19. Antifungal Pisum sativum defensin 1 interacts with Neurospora crassa cyclin F related to the cell cycle.

    Science.gov (United States)

    Lobo, Denise S; Pereira, Iuri B; Fragel-Madeira, Lucianne; Medeiros, Luciano N; Cabral, Luiz M; Faria, Jane; Bellio, Maria; Campos, Reinaldo C; Linden, Rafael; Kurtenbach, Eleonora

    2007-01-30

    Plant defensins, components of the plant innate immune system, are cationic cysteine-rich antifungal peptides. Evidence from the literature [Thevissen, K., et al. (2003) Peptides 24, 1705-1712] has demonstrated that patches of fungi membrane containing mannosyldiinositolphosphorylceramide and glucosylceramides are selective binding sites for the plant defensins isolated from Dahlia merckii and Raphanus sativus, respectively. Whether plant defensins interact directly or indirectly with fungus intracellular targets is unknown. To identify physical protein-protein interactions, a GAL4-based yeast two-hybrid system was performed using the antifungal plant peptide Pisum sativum defensin 1 (Psd1) as the bait. Target proteins were screened within a Neurospora crassa cDNA library. Nine out of 11 two-hybrid candidates were nuclear proteins. One clone, detected with high frequency per screening, presented sequence similarity to a cyclin-like protein, with F-box and WD-repeat domains, related to the cell cycle control. GST pull-down assay corroborated in vitro this two-hybrid interaction. Fluorescence microscopy analysis of FITC-conjugated Psd1 and DAPI-stained fungal nuclei showed in vivo the colocalization of the plant peptide Psd1 and the nucleus. Analysis of the DNA content of N. crassa conidia using flow cytometry suggested that Psd1 directed cell cycle impairment and caused conidia to undergo endoreduplication. The developing retina of neonatal rats was used as a model to observe the interkinetic nuclear migration during proliferation of an organized tissue from the S toward the M phase of the cell cycle in the presence of Psd1. The results demonstrated that the plant defensin Psd1 regulates interkinetic nuclear migration in retinal neuroblasts. PMID:17240982

  20. Effects of long-term reduced tillage on weed infestation of pea (Pisum sativum L.

    Directory of Open Access Journals (Sweden)

    Andrzej Woźniak

    2014-09-01

    Full Text Available The study evaluated weed infestation of pea (Pisum sativum L. cultivated under conditions of conventional (CT, reduced (RT and herbicide tillage (HT. It demonstrated the highest weed density per m2 in plots with the herbicide (HT and reduced (RT systems and significantly lower weed infestation in plots cultivated in the conventional system (CT. In addition, more weeds occurred at the third leaf stage (13/14 in BBCH scale than at the pod development stage (73/74 BBCH of pea. The highest biomass was produced by weeds in the herbicide system (HT, a lower one – in the reduced system (RT, and the lowest one – in the conventional system (CT. The air-dry weight of weeds depended also on pea development stage. At the pod development stage (73/74 BBCH, the air-dry weight of weeds was significantly higher than at the third leaf stage (13/14 BBCH. The tillage system was also observed to influence the species composition of weeds. This trait was also affected by the period of weed infestation assessment. At the third leaf stage of pea (13/14 BBCH, there occurred 26 weed species, including 24 annual ones. The most abundant species included: Chenopodium album L., Stellaria media (L. Vill., Capsella bursa-pastoris (L. Med., Matricaria inodora L., Thlaspi arvense L., and Fallopia convolvulus (L. A. Löve. At the pod development stage (73/74 BBCH, the pea crop was colonized by 24 weed species, including 3 perennial ones. At this stage the predominant species included: Avena fatua L., Amaranthus retroflexus L., Papaver rhoeas L., Echinochloa crus-galli (L. P.B., Matricaria inodora L., and Galeopsis tetrahit L.

  1. Bean pod mottle virus: a new powerful tool for functional genomics studies in Pisum sativum.

    Science.gov (United States)

    Meziadi, Chouaib; Blanchet, Sophie; Richard, Manon M S; Pilet-Nayel, Marie-Laure; Geffroy, Valérie; Pflieger, Stéphanie

    2016-08-01

    Pea (Pisum sativum L.) is an important legume worldwide. The importance of pea in arable rotations and nutritional value for both human and animal consumption have fostered sustained production and different studies to improve agronomic traits of interest. Moreover, complete sequencing of the pea genome is currently underway and will lead to the identification of a large number of genes potentially associated with important agronomic traits. Because stable genetic transformation is laborious for pea, virus-induced gene silencing (VIGS) appears as a powerful alternative technology for determining the function of unknown genes. In this work, we present a rapid and efficient viral inoculation method using DNA infectious plasmids of Bean pod mottle virus (BPMV)-derived VIGS vector. Six pea genotypes with important genes controlling biotic and/or abiotic stresses were found susceptible to BPMV carrying a GFP reporter gene and showed fluorescence in both shoots and roots. In a second step, we investigated 37 additional pea genotypes and found that 30 were susceptible to BPMV and only 7 were resistant. The capacity of BPMV to induce silencing of endogenes was investigated in the most susceptible genotype using two visual reporter genes: PsPDS and PsKORRIGAN1 (PsKOR1) encoding PHYTOENE DESATURASE and a 1,4-β-D-glucanase, respectively. The features of the 'one-step' BPMV-derived VIGS vector include (i) the ease of rub-inoculation, without any need for biolistic or agro-inoculation procedures, (ii) simple cost-effective procedure and (iii) noninterference of viral symptoms with silencing. These features make BPMV the most adapted VIGS vector in pea to make low- to high-throughput VIGS studies.

  2. Growth, seed development and genetic analysis in wild type and Def mutant of Pisum sativum L

    Directory of Open Access Journals (Sweden)

    Ayeh Kwadwo

    2011-11-01

    Full Text Available Abstract Background The def mutant pea (Pisum sativum L showed non-abscission of seeds from the funicule. Here we present data on seed development and growth pattern and their relationship in predicting this particular trait in wild type and mutant lines as well as the inheritance pattern of the def allele in F2 and F3 populations. Findings Pod length and seed fresh weight increase with fruit maturity and this may affect the abscission event in pea seeds. However, the seed position in either the distal and proximal ends of the pod did not show any difference. The growth factors of seed fresh weight (FW, width of funicles (WFN, seed width (SW and seed height (SH were highly correlated and their relationships were determined in both wild type and def mutant peas. The coefficient of determination R2 values for the relationship between WFN and FW, SW and SH and their various interactions were higher for the def dwarf type. Stepwise multiple regression analysis showed that variation of WFN was associated with SH and SW. Pearson's chi square analysis revealed that the inheritance and segregation of the Def locus in 3:1 ratio was significant in two F2 populations. Structural analysis of the F3 population was used to confirm the inheritance status of the Def locus in F2 heterozygote plants. Conclusions This study investigated the inheritance of the presence or absence of the Def allele, controlling the presence of an abscission zone (AZ or an abscission-less zone (ALZ forming in wild type and mutant lines respectively. The single major gene (Def controlling this phenotype was monogenic and def mutants were characterized and controlled by the homozygous recessive def allele that showed no palisade layers in the hilum region of the seed coat.

  3. Preservative potential of cumin essential oil for Pisum sativum L. during storage

    Directory of Open Access Journals (Sweden)

    Kumar Narendra

    2016-04-01

    Full Text Available The samples of stored seeds of pea (Pisum sativum L. were collected from 30 farmer markets. The mycobiota analysis showed presence of 15 fungal species and one species of insect Callosobruchus chinensis. The fungi such as Aspergillus flavus, A. niger, A. ochraceous, A. terreus were found to be dominant based on percent frequency of each in blotter method in unsterilized and sterilized seeds 18.9-7.9, 15.0-3.9, 12.2-3.7, 10.1-1.7, respectively, and in agar plate technique 17.9-8.3, 15.1-9.5, 12.8-5, 7.9.7-6.7, respectively. These species showed reduction in terms of weight loss, germination and protein content in pathogenicity testing. Essential oil extracted by hydrodistillation from fruits of Cuminum cyminum L. was evaluated against the most common occurring funi such as A. flavus and A. niger as well as the insect species C. chinensis and the oil exhibited high toxicity. The oil killed the tested fungi and showed thermostable nature at its minimum inhibitory concentration (MIC of 400 ppm. The oil safely preserved pea seeds up to 120 days at 0.50 (1,000 ppm and 0.76 ml (1,500 ppm in polyethylene and jute bags of 500 ml capacity containing 400 g seeds separately. There were no changes in organoleptic appereance of food seeds during storage. The oil has beneficial effect on number of visible nodule formation and shoot and root dry biomass of 15-day-old plants in comparison to control sets. The cumin oil was analyzed by gas chromatography (GC and gas chromatography-mass spectrometry (GC-MS.

  4. Effect of Rhizobium inoculation of seeds and foliar fertilization on productivity of Pisum sativum L.

    Directory of Open Access Journals (Sweden)

    Tadeusz Zając

    2013-07-01

    Full Text Available Pea (Pisum sativum L. is the second most important grain legume crop in the world which has a wide array of uses for human food and fodder. One of the major factors that determines the use of field pea is the yield potential of cultivars. Presently, pre-sowing inoculation of pea seeds and foliar application of microelement fertilizers are prospective solutions and may be reasonable agrotechnical options. This research was undertaken because of the potentially high productivity of the 'afila' morphotype in good wheat complex soils. The aim of the study was to determine the effect of vaccination with Rhizobium and foliar micronutrient fertilization on yield of the afila pea variety. The research was based on a two-year (2009–2010 controlled field experiment, conducted in four replicates and carried out on the experimental field of the Bayer company located in Modzurów, Silesian region. experimental field soil was Umbrisol – slightly degraded chernozem, formed from loess. Nitragina inoculant, as a source of symbiotic bacteria, was applied before sowing seeds. Green area index (GAI of the canopy, photosynthetically active radiation (PAR, and normalized difference vegetation index (NDVI were determined at characteristic growth stages. The presented results of this study on symbiotic nitrogen fixation by leguminous plants show that the combined application of Nitragina and Photrel was the best combination for productivity. Remote measurements of the pea canopy indexes indicated the formation of the optimum leaf area which effectively used photosynthetically active radiation. The use of Nitragina as a donor of effective Rhizobium for pea plants resulted in slightly higher GAI values and the optimization of PAR and NDVI. It is not recommended to use foliar fertilizers or Nitragina separately due to the slowing of pea productivity.

  5. Roles for auxin during morphogenesis of the compound leaves of pea ( Pisum sativum).

    Science.gov (United States)

    DeMason, Darleen A; Chawla, Rekha

    2004-01-01

    The goal of this study was to explore the impact of the plant growth regulator auxin on the development of compound leaves in pea. Wildtype ( WT) plantlets, as well as those of two leaf mutants, acacia ( tl) and tendrilled acacia ( uni-tac) of pea ( Pisum sativum L.), were grown on media containing the auxin-transport inhibitors 2,3,5-triiodobenzoic acid (TIBA), N-(1-naphthyl)phthalamic acid (NPA), or the auxin antagonist, p-chlorophenoxyisobutyric acid (PCIB). The resulting plantlets were carefully analyzed morphologically, by scanning electron microscopy and for Uni gene expression using quantitative reverse transcription-polymerase chain reaction. Auxin transport was measured in WT leaf parts using [(14)C]indole-3-acetic acid. Relative Uni gene expression was determined in shoot tips of a range of leaf-form mutants. Morphological abnormalities were observed for all genotypes examined. The terminal tendrils on WT plants were converted to leaflets, stubs or were aborted. The number of pinna pairs produced on leaves was reduced, with the distal forms being eliminated before the proximal ones. Some leaves were converted to simple, including tri-and bilobed, forms. These treatments phenocopy the uni-tac and unifoliata ( uni) mutants of pea. In the most extreme situations, leaf blades were completely lost leaving only a pair of stipules or scale leaves. Polar auxin transport was basipetal for all leaf parts. Uni gene expression in shoot tips was significantly reduced in 60 microM NPA and TIBA. Uni mRNA was more abundant in tl, af and af tl and reduced in the uni mutants compared to WT. These results indicate that an auxin gradient plays fundamental roles in controlling morphogenesis in the compound leaves of pea and specifically it: (i). is the driving force for leaf growth and pinna determination; (ii). is necessary for pinna initiation; and (iii). controls subsequent pinna development. PMID:12942326

  6. Cell wall yield properties of growing tissue: evaluation by in vivo stress relaxation. [Pisum sativus L

    Energy Technology Data Exchange (ETDEWEB)

    Cosgrove, D.J.

    1985-06-01

    Growing pea stem tissue, when isolated from an external supply of water, undergoes stress relaxation because of continued loosening of the cell wall. A theoretical analysis is presented to show that such stress relaxation should result in an exponential decrease in turgor pressure down to the yield threshold (Y), with a rate constant given by phi epsilon where phi is the metabolically maintained irreversible extensibility of the cell wall and epsilon is the volumetric elastic modulus of the cell. Stress relaxation was measured in pea (Pisum sativus L.) stem segments using the pressure microprobe technique. From the rate of stress relaxation, phi of segments pretreated with water was calculated to be 0.08 per megapascal per hour while that of auxin-pretreated tissue was 0.24 per megapascal per hour. These values agreed closely with estimates of phi made by a steady-state technique. The yield threshold (0.29 megapascal) was not affected by auxin. A theoretical analysis is also presented to show that the tissue hydraulic conductance may be estimated from the T/sub 1/2/ of tissue swelling. Experimentally, pea stems had a swelling T/sub 1/2/ of 2.0 minutes, corresponding to a relative hydraulic conductance of about 2.0 per megapascal per hour. This value is at least 8 times larger than phi. From these data and from computer modeling, it appears that the radial gradient in water potential which sustains water uptake in growing pea segments is small (0.04 megapascal). This means that hydraulic conductance does not substantially restrict growth. The results also demonstrate that the stimulation of growth by auxin can be entirely accounted for by the change in phi.

  7. Sitona lineatus (Coleoptera: Curculionidae) Larval Feeding on Pisum sativum L. Affects Soil and Plant Nitrogen.

    Science.gov (United States)

    Cárcamo, Héctor A; Herle, Carolyn E; Lupwayi, Newton Z

    2015-01-01

    Adults of Sitona lineatus (pea leaf weevil, PLW) feed on foliage of several Fabaceae species but larvae prefer to feed on nodules of Pisum sativum L. and Vicia faba L. Indirectly, through their feeding on rhizobia, weevils can reduce soil and plant available nitrogen (N). However, initial soil N can reduce nodulation and damage by the weevil and reduce control requirements. Understanding these interactions is necessary to make integrated pest management recommendations for PLW. We conducted a greenhouse study to quantify nodulation, soil and plant N content, and nodule damage by weevil larvae in relation to soil N amendment with urea, thiamethoxam insecticide seed coating and crop stage. PLWs reduced the number of older tumescent (multilobed) nodules and thiamethoxam addition increased them regardless of other factors. Nitrogen amendment significantly increased soil available N (>99% nitrate) as expected and PLW presence was associated with significantly lower levels of soil N. PLW decreased plant N content at early flower and thiamethoxam increased it, particularly at late flower. The study illustrated the complexity of interactions that determine insect herbivory effects on plant and soil nutrition for invertebrates that feed on N-fixing root nodules. We conclude that effects of PLW on nodulation and subsequent effects on plant nitrogen are more pronounced during the early growth stages of the plant. This suggests the importance of timing of PLW infestation and may explain the lack of yield depression in relation to this pest observed in many field studies. Also, pea crops in soils with high levels of soil N are unlikely to be affected by this herbivore and should not require insecticide inputs.

  8. The tropic response of plant roots to oxygen: oxytropism in Pisum sativum L

    Science.gov (United States)

    Porterfield, D. M.; Musgrave, M. E.

    1998-01-01

    Plant roots are known to orient growth through the soil by gravitropism, hydrotropism, and thigmotropism. Recent observations of plant roots that developed in a microgravity environment in space suggested that plant roots may also orient their growth toward oxygen (oxytropism). Using garden pea (Pisum sativum L. cv. Weibul's Apollo) and an agravitropic mutant (cv. Ageotropum), root oxytropism was studied in the controlled environment of a microrhizotron. A series of channels in the microrhizotron allowed establishment of an oxygen gradient of 0.8 mmol mol-1 mm-1. Curvature of seedling roots was determined prior to freezing the roots for subsequent spectrophotometric determinations of alcohol dehydrogenase activity. Oxytropic curvature was observed all along the gradient in both cultivars of pea. The normal gravitropic cultivar showed a maximal curvature of 45 degrees after 48 h, while the agravitropic mutant curved to 90 degrees. In each cultivar, the amount of curvature declined as the oxygen concentration decreased, and was linearly related to the root elongation rate. Since oxytropic curvature occurred in roots exposed to oxygen concentrations that were not low enough to induce the hypoxically responsive protein alcohol dehydrogenase, we suspect that the oxygen sensor associated with oxytropism does not control the induction of hypoxic metabolism. Our results indicate that oxygen can play a critical role in determining root orientation as well as impacting root metabolic status. Oxytropism allows roots to avoid oxygen-deprived soil strata and may also be the basis of an auto-avoidance mechanism, decreasing the competition between roots for water and nutrients as well as oxygen.

  9. Antioxidant enzymes regulate reactive oxygen species during pod elongation in Pisum sativum and Brassica chinensis.

    Science.gov (United States)

    Liu, Nan; Lin, Zhifang; Guan, Lanlan; Gaughan, Gerald; Lin, Guizhu

    2014-01-01

    Previous research has focused on the involvement of reactive oxygen species (ROS) in cell wall loosening and cell extension in plant vegetative growth, but few studies have investigated ROS functions specifically in plant reproductive organs. In this study, ROS levels and antioxidant enzyme activities were assessed in Pisum sativum and Brassica chinensis pods at five developmental stages. In juvenile pods, the high levels of O2.- and .OH indicates that they had functions in cell wall loosening and cell elongation. In later developmental stages, high levels of .OH were also related to increases in cell wall thickness in lignified tissues. Throughout pod development, most of the O2.- was detected on plasma membranes of parenchyma cells and outer epidermis cells of the mesocarp, while most of the H2O2 was detected on plasma membranes of most cells throughout the mesocarp. This suggests that these sites are presumably the locations of ROS generation. The antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) apparently contributed to ROS accumulation in pod wall tissues. Furthermore, specifically SOD and POD were found to be associated with pod growth through the regulation of ROS generation and transformation. Throughout pod development, O2.- decreases were associated with increased SOD activity, while changes in H2O2 accumulation were associated with changes in CAT and POD activities. Additionally, high POD activity may contribute to the generation of(.)OH in the early development of pods. It is concluded that the ROS are produced in different sites of plasma membranes with the regulation of antioxidant enzymes, and that substantial ROS generation and accumulation are evident in cell elongation and cell wall loosening in pod wall cells. PMID:24503564

  10. Vat, an Amazing Gene Conferring Resistance to Aphids and Viruses They Carry: From Molecular Structure to Field Effects

    Science.gov (United States)

    Boissot, Nathalie; Schoeny, Alexandra; Vanlerberghe-Masutti, Flavie

    2016-01-01

    We review half a century of research on Cucumis melo resistance to Aphis gossypii from molecular to field levels. The Vat gene is unique in conferring resistance to both A. gossypii and the viruses it transmits. This double phenotype is aphid clone-dependent and has been observed in 25 melon accessions, mostly from Asia. It is controlled by a cluster of genes including CC-NLR, which has been characterized in detail. Copy-number polymorphisms (for the whole gene and for a domain that stands out in the LLR region) and single-nucleotide polymorphisms have been identified in the Vat cluster. The role of these polymorphisms in plant/aphid interactions remains unclear. The Vat gene structure suggests a functioning with separate recognition and response phases. During the recognition phase, the VAT protein is thought to interact (likely indirectly) with an aphid effector introduced during cell puncture by the aphid. A few hours later, several miRNAs are upregulated in Vat plants. Peroxidase activity increases, and callose and lignin are deposited in the walls of the cells adjacent to the stylet path, disturbing aphid behavior. In aphids feeding on Vat plants, Piwi-interacting RNA-like sequences are abundant and the levels of other miRNAs are modified. At the plant level, resistance to aphids is quantitative (aphids escape the plant and display low rates of reproduction). Resistance to viruses is qualitative and local. Durability of NLR genes is highly variable. A. gossypii clones are adapted to Vat resistance, either by introducing a new effector that interferes with the deployment of plant defenses, or by adapting to the defenses it triggered. Viruses transmitted in a non-persistent manner cannot adapt to Vat resistance. At population level, Vat reduces aphid density and genetic diversity. The durability of Vat resistance to A. gossypii populations depends strongly on the agro-ecosystem, including, in particular, the presence of other cucurbit crops serving as

  11. Trophic interactions between rhizosphere bacteria and bacterial feeders influenced by phosphate and aphids in barley

    DEFF Research Database (Denmark)

    Strandmark, Lisa Bjørnlund; Mørk, Søren; Madsen, Mette Vestergård;

    2006-01-01

    -proteobacteria increased with P addition. To evaluate if differences in bacteria in terms of their quality as food could partly explain the observed differences in protozoan and nematode abundances, growth of the flagellate Cercomonas sp. was assessed with 935 bacteria isolated from the different treatments. This assay......The aim was to study the effects of P fertilization and leaf aphid attack on the trophic interactions of bacteria and bacterial feeders in the rhizospheres of barley plants. The density of protozoa peaked in the rhizospheres of plants fertilized with N and P, whereas nematodes peaked...... indicated that bacterial isolates were of higher food quality to Cercomonas sp. in NP than in N rhizospheres when plants were subjected to aphid attack. Bacteria of high and low food quality for Cercomonas sp., respectively, were fed to the nematode Caenorhabditis elegans and larval production examined. a...

  12. Demographic parameters of cotton aphid, Aphis gossypii Glover (Homoptera: Aphididae) on five cotton cultivars

    Institute of Scientific and Technical Information of China (English)

    JABRAEIL RAZMJOU; SAEID MOHARRAMIPOUR; YAGHOUB FATHIPOUR; SEYED ZIAEDDIN MIRHOSEINI

    2006-01-01

    Life table parameters of the cotton aphid, Aphis gossypii Glover, were estimated on five cotton cultivars ('Sealand' ,'Siokra' ,'Varamin' ,'Bakhtegan' and 'Sahel'). Demographic parameters of the cotton aphid were assessed at 27.5 ± 1 ℃, 65% ± 10% RH and a photoperiod of 14:10 (L: D)h. The shortest developmental time for the nymphal stages was 5.5 days on 'Siokra' and the longest was 6.1 days on 'Sealand'. The highest offspring per female was 29.6 on 'Sahel' and the lowest was 15.3 on 'Sealand'. The rm values varied from 0.272 on 'Sealand' to 0.382 (day-1) on 'Varamin'. Jackknife estimates of the A.gossypii parameters on these cultivars indicated the greatest developmental rate and fecundity on 'Varamin' and the poorest on 'Sealand' cultivar.

  13. Poisoning of Canada geese in Texas by parathion sprayed for control of Russian wheat aphid

    Science.gov (United States)

    Flickinger, Edward L.; Juenger, Gary; Roffe, Thomas J.; Smith, Milton R.; Irwin, Roy J.

    1991-01-01

    Approximately 200 Canada geese (Branta canadensis) died at a playa lake in the Texas Panhandle shortly after a winter wheat field in the basin adjacent to the lake was treated with parathion to control newly invading Russian wheat aphids (Diuraphis noxia). No evidence of infectious disease was diagnosed during necropsies of geese. Brain ChE activities were depressed up to 77% below normal. Parathion residues in GI tract contents of geese ranged from 4 to 34 ppm. Based on this evidence, parathion was responsible for the goose mortalities. Parathion applications to winter wheat will undoubtedly increase if parathion is applied for control of both Russian wheat aphids and greenbugs (Schizaphis graminum). Geese may potentially be exposed to widespread applications of parathion from fall to spring, essentially their entire wintering period.

  14. Aphids (Hemiptera: Aphidomorpha of the Botanic Garden of the Jagiellonian University, Kraków*

    Directory of Open Access Journals (Sweden)

    Starowicz Marzena

    2015-12-01

    Full Text Available The paper presents results of faunistic investigations of aphids (Aphidomorpha in the Botanic Garden of the Jagiellonian University, Kraków, in the Kraków – Wieluń Upland. During two seasons of research (2011, 2012 two aphid species from the family Adelgidae and 50 species from the family Aphididae, associated with 66 host plants were recorded. The following species – Eriosoma anncharlotteae Danielsson, 1979, Capitophorus elaeagni (Del Guercio, 1894, Rhopalosiphoninus (Neorhopalosiphoninus staphyleae staphyleae (Koch, 1854, Eulachnus brevipilosus Börner, 1940 and E. cembrae Börner, 1950 – are new for the Kraków – Wieluń Upland. Seven of the species recorded are regarded as alien to Poland.

  15. Fitness Effects of Food Resources on the Polyphagous Aphid Parasitoid, Aphidius colemani Viereck (Hymenoptera: Braconidae: Aphidiinae).

    Science.gov (United States)

    Charles, Jennifer J; Paine, Timothy D

    2016-01-01

    Conservation biological control involving the polyphagous aphid parasitoid, Aphidius colemani Viereck, may include provisioning resources from a variety of plant sources. The fitness of adult A. colemani was enhanced with the provision of food resources such as floral nectar from a range of both native and introduced plant species and aphid honeydew under laboratory conditions. However, enhanced fitness appeared to be species specific rather than associated with the whether the plant was a native or an introduced species. Parasitoid survival and fecundity were enhanced significantly in response to the availability of floral nectar and honeydew compared to the response to available extrafloral nectar. These positive effects on the parasitoid's reproductive activity can improve the effectiveness of conservation biological control in nursery production systems because of the abundance and diversity of floral resources within typical production areas. Additionally, surrounding areas of invasive weeds and native vegetation could serve as both floral resources and honeydew food resources for A. colemani.

  16. Fitness Effects of Food Resources on the Polyphagous Aphid Parasitoid, Aphidius colemani Viereck (Hymenoptera: Braconidae: Aphidiinae)

    Science.gov (United States)

    Charles, Jennifer J.; Paine, Timothy D.

    2016-01-01

    Conservation biological control involving the polyphagous aphid parasitoid, Aphidius colemani Viereck, may include provisioning resources from a variety of plant sources. The fitness of adult A. colemani was enhanced with the provision of food resources such as floral nectar from a range of both native and introduced plant species and aphid honeydew under laboratory conditions. However, enhanced fitness appeared to be species specific rather than associated with the whether the plant was a native or an introduced species. Parasitoid survival and fecundity were enhanced significantly in response to the availability of floral nectar and honeydew compared to the response to available extrafloral nectar. These positive effects on the parasitoid’s reproductive activity can improve the effectiveness of conservation biological control in nursery production systems because of the abundance and diversity of floral resources within typical production areas. Additionally, surrounding areas of invasive weeds and native vegetation could serve as both floral resources and honeydew food resources for A. colemani. PMID:26808191

  17. Adaptation of aphid stylectomy for analyses of proteins and mRNAs in barley phloem sap

    OpenAIRE

    Gaupels, Frank; Buhtz, Anja; Knauer, Torsten; Deshmukh, Sachin; Waller, Frank; van Bel, Aart J. E.; Kogel, Karl-Heinz; Kehr, Julia

    2008-01-01

    Sieve tubes are transport conduits not only for photoassimilates but also for macromolecules and other compounds that are involved in sieve tube maintenance and systemic signalling. In order to gain sufficient amounts of pure phloem exudates from barley plants for analyses of the protein and mRNA composition, a previously described stylectomy set-up was optimized. Aphids were placed in sealed cages, which, immediately after microcauterization of the stylets, were flooded with water-saturated ...

  18. Norway spruce and spruce shoot aphid as indicators of traffic pollution

    Energy Technology Data Exchange (ETDEWEB)

    Viskari, E-L.; Koessi, S. [Kuopio Univ. (Finland). Dept. of Ecology and Environmental Science; Holopainen, J.K. [Kuopio Univ. (Finland). Dept. of Ecology and Environmental Science; Agricultural Research Centre, Plant Production Research, Jokioinen (Finland)

    2000-07-01

    Two-year-old Norway spruce (Picea abies (L.) Karst) seedlings were exposed to traffic emissions along roadsides with three different traffic densities and speed limits; highway, street and a quiet local road. The responses of the exposed seedlings as a host plant and those of spruce shoot aphid (Cinara pilicornis Hartig) were studied. The concentrations of soluble N and free amino acids, defence chemicals (total phenolics, monoterpenes) were analysed, and aphid growth and reproduction were studied. Along the highway, street and at the local road control site, the atmospheric concentrations of black carbon (BC) and oxides of N (NO{sub x}) were measured for 1 week during the experiment. The BC data indicate deposition of organic particulate compounds along the highway and street. The NO{sub x} concentrations along the highway and street showed great diurnal variation, but the average NO{sub x} concentrations were relatively low. Thus, no changes in N metabolism or growth of the exposed Norway spruce seedlings were found. Along the street, the concentrations of many individual free amino acids, such as proline, as well as total amino acid concentrations, were lower than at the associated control site. Correspondingly, there was also no increase in spruce shoot aphid mean relative growth rate. The aphid reproduction, however, increased along the highway and is suggested to be due to more conducive microclimatic conditions at the exposure site or lack of natural enemies. No changes in defence chemicals (total phenolics, monoterpenes) in relation to the traffic exposure were found. Instead, the microclimatic conditions (temperature, solar irradiation) seemed to affect the concentration of total phenolics. (Author)

  19. Use of ryegrass strips to enhance biological control of aphids by ladybirds in wheat fields

    Institute of Scientific and Technical Information of China (English)

    Zhao-Ke Dong; Feng-Juan Gao; Run-Zhi Zhang

    2012-01-01

    Non-crop habitats may play a vital role in conservation biological control.This study tested the effect of ryegrass (Lolium muitiflorum L.) strips on aphid and ladybird populations in adjacent winter wheat fields.The field experiment was conducted in three ryegrass-margin wheat plots and three control plots in 2010 in North China.In spring,the same aphid species,Sitobion miscanthi (Takahashi),was found in both the ryegrass strips and wheat plots.The population density of ladybirds in the ryegrass strips (3.5±0.9/m2) was significantly higher than in the wheat plots (1.5±0.5/m2).We cut the ryegrass,forcing the ladybirds to migrate to the wheat fields.Three and eight days after cutting the ryegrass,the aphid numbers in the ryegrass-margin wheat plots decreased significantly:they were 19.9% and 53.6%,respectively,lower than in control plots.In the early period of ladybird population development,the percentage of larvae was greater in the ryegrass-margin wheat plots than in controls,and the peak number of pupae in the ryegrass-margin wheat plots occurred 5 days earlier than in the control plots.The results suggest that ryegrass strips may promote the development of ladybird populations.Cutting ryegrass can manipulate ladybirds to enhance biological aphid control in wheat fields.The efficiency of this management approach is discussed.

  20. Evolutionary Relationships of Three New Species of Enterobacteriaceae Living as Symbionts of Aphids and Other Insects

    OpenAIRE

    Moran, Nancy A.; Russell, Jacob A; Koga, Ryuichi; Fukatsu, Takema

    2005-01-01

    Ecological studies on three bacterial lineages symbiotic in aphids have shown that they impose a variety of effects on their hosts, including resistance to parasitoids and tolerance to heat stress. Phylogenetic analyses of partial sequences of gyrB and recA are consistent with previous analyses limited to 16S rRNA gene sequences and yield improved confidence of the evolutionary relationships of these symbionts. All three symbionts are in the Enterobacteriaceae. One of the symbionts, here give...

  1. Rothamsted’s aphid-resistant wheat – a turning point for GMOs?

    OpenAIRE

    Lynas Mark

    2012-01-01

    Abstract Rothamsted Research mounted a successful counter-campaign in response to a threat by environmental protesters to destroy their research project examining aphid-resistant genetically modified (GM) wheat. This involved the use of online media, petitions, and other tools, by which researchers engaged directly with media and the general public in defense of their work. Lessons are suggested for other researchers in the controversial field of GM plant breeding.

  2. Non-pest prey do not disrupt aphid predation by a web-building spider.

    Science.gov (United States)

    Welch, K D; Whitney, T D; Harwood, J D

    2016-02-01

    A generalist predator's ability to contribute to biological control is influenced by the decisions it makes during foraging. Predators often use flexible foraging tactics, which allows them to pursue specific types of prey at the cost of reducing the likelihood of capturing other types of prey. When a pest insect has low nutritional quality or palatability for a predator, the predator is likely to reject that prey in favour of pursuing alternative, non-pest prey. This is often thought to limit the effectiveness of generalist predators in consuming aphids, which are of low nutritional quality for many generalist predators. Here, we report behavioural assays that test the hypothesis that the generalist predator, Grammonota inornata (Araneae: Linyphiidae), preferentially forages for a non-pest prey with high nutritional quality (springtails), and rejects a pest prey with low nutritional quality (aphids). In no-choice assays, molecular gut-content analysis revealed that spiders continued to feed on the low-quality aphids at high rates, even when high-quality springtails were readily available. When provided a choice between aphids and springtails in two-way choice tests, spiders did not show the expected preference for springtails. Decision-making by spiders during foraging therefore appears to be sub-optimal, possibly because of attraction to the less frequently encountered of two preys as part of a dietary diversification strategy. These results indicate that behavioural preferences alone do not necessarily compromise the pest-suppression capacity of natural enemies: even nutritionally sub-optimal pest prey can potentially be subject to predation and suppression by natural enemies. PMID:26584533

  3. Identification and characterization of resistance to cowpea aphid (Aphis craccivora Koch) in Medicago truncatula

    OpenAIRE

    Kamphuis, Lars G.; Gao, Lingling; Singh, Karam B.

    2012-01-01

    Background Cowpea aphid (CPA; Aphis craccivora) is the most important insect pest of cowpea and also causes significant yield losses in other legume crops including alfalfa, beans, chickpea, lentils, lupins and peanuts. In many of these crops there is no natural genetic resistance to this sap-sucking insect or resistance genes have been overcome by newly emerged CPA biotypes. Results In this study, we screened a subset of the Medicago truncatula core collection of the South Australian Researc...

  4. The over-expression of a chrysanthemum WRKY transcription factor enhances aphid resistance.

    Science.gov (United States)

    Li, Peiling; Song, Aiping; Gao, Chunyan; Jiang, Jiafu; Chen, Sumei; Fang, Weimin; Zhang, Fei; Chen, Fadi

    2015-10-01

    Members of the large WRKY transcription factor family are responsible for the regulation of plant growth, development and the stress response. Here, five WRKY members were isolated from chrysanthemum. They each contained a single WRKY domain and a C2H2 zinc finger motif, so were classified into group II. Transient expression experiments demonstrated that all five were expressed in the nucleus, although CmWRKY42 was also expressed in the cytoplasm. When expressed heterologously in yeast, the products of CmWRKY22 and CmWRKY48 exhibited transactivation activity, while those of CmWRKY21, CmWRKY40 and CmWRKY42 did not. The transcription of the five CmWRKY genes was profiled when the plants were challenged with a variety of abiotic and biotic stress agents, as well as being treated with various phytohormones. CmWRKY21 proved to be markedly induced by salinity stress, and suppressed by high temperature exposure; CmWRKY22 was induced by high temperature exposure; CmWRKY40 was highly induced by salinity stress, and treatment with either abscisic acid (ABA) or methyl jasmonate (MeJA); CmWRKY42 was up-regulated by salinity stress, low temperature, ABA and MeJA treatment and aphid infestation; CmWRKY48 was induced by drought stress, ABA and MeJA treatment and aphid infestation. The function of CmWRKY48 was further investigated by over-expressing it transgenically. The constitutive expression of this transcription factor inhibited the aphids' population growth capacity, suggesting that it may represent an important component of the plant's defense machinery against aphids. PMID:26184088

  5. Toxicity of Three Insecticides to Lysiphlebus fabarum, a Parasitoid of the Black Bean Aphid, Aphis fabae

    OpenAIRE

    Sabahi, Qodratollah; Rasekh, Arash; Michaud, J.P.

    2011-01-01

    The toxicity of three insecticides to Lysiphlebus fabarum (Marshall) (Hymenoptera: Braconidae: Aphidiinae), a parasitoid of Aphis fabae Scopoli (Hemiptera: Aphididae), was investigated using IOBC/wprs protocols. Abamectin 1.8 EC, imidacloprid 350 SC, and pymetrozine 25 WP were tested under laboratory conditions at recommended field rates. Immature stages of the parasitoid were exposed to materials by briefly dipping mummified aphids into insecticide solutions/suspensions or water (controls). ...

  6. Analysis of carotenoid compounds in aphids by Raman imaging and mass spectrometry

    OpenAIRE

    sprotocols

    2015-01-01

    Authors: Pierre Brat, Jean Christophe Valmalette, Christian Mertz, George de Sousa, Aviv Dombrovsky, Maria Capovilla & Alain Robichon ### Abstract Carotenoids are compounds synthesized in plants, bacteria and fungi, closely associated to the chlorophyll to perform photosynthesis. A spectacular evolutionary achievement allowed the aphid to produce carotenoids obviously by lateral transfer of genes from fungi. We have recently documented that these molecules are involved in photo c...

  7. Rothamsted’s aphid-resistant wheat – a turning point for GMOs?

    Directory of Open Access Journals (Sweden)

    Lynas Mark

    2012-10-01

    Full Text Available Abstract Rothamsted Research mounted a successful counter-campaign in response to a threat by environmental protesters to destroy their research project examining aphid-resistant genetically modified (GM wheat. This involved the use of online media, petitions, and other tools, by which researchers engaged directly with media and the general public in defense of their work. Lessons are suggested for other researchers in the controversial field of GM plant breeding.

  8. Non-pest prey do not disrupt aphid predation by a web-building spider.

    Science.gov (United States)

    Welch, K D; Whitney, T D; Harwood, J D

    2016-02-01

    A generalist predator's ability to contribute to biological control is influenced by the decisions it makes during foraging. Predators often use flexible foraging tactics, which allows them to pursue specific types of prey at the cost of reducing the likelihood of capturing other types of prey. When a pest insect has low nutritional quality or palatability for a predator, the predator is likely to reject that prey in favour of pursuing alternative, non-pest prey. This is often thought to limit the effectiveness of generalist predators in consuming aphids, which are of low nutritional quality for many generalist predators. Here, we report behavioural assays that test the hypothesis that the generalist predator, Grammonota inornata (Araneae: Linyphiidae), preferentially forages for a non-pest prey with high nutritional quality (springtails), and rejects a pest prey with low nutritional quality (aphids). In no-choice assays, molecular gut-content analysis revealed that spiders continued to feed on the low-quality aphids at high rates, even when high-quality springtails were readily available. When provided a choice between aphids and springtails in two-way choice tests, spiders did not show the expected preference for springtails. Decision-making by spiders during foraging therefore appears to be sub-optimal, possibly because of attraction to the less frequently encountered of two preys as part of a dietary diversification strategy. These results indicate that behavioural preferences alone do not necessarily compromise the pest-suppression capacity of natural enemies: even nutritionally sub-optimal pest prey can potentially be subject to predation and suppression by natural enemies.

  9. Aphid-induced Defences in Chilli Affect Preferences of the Whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae)

    OpenAIRE

    Saad, Khalid A.; M. N. Mohamad Roff; Hallett, Rebecca H.; Idris, A. B.

    2015-01-01

    The sweetpotato whitefly (WF), Bemisia tabaci, is a major pest that damages a wide range of vegetable crops in Malaysia. WF infestation is influenced by a variety of factors, including previous infestation of the host plant by other insect pests. This study investigated the effects of previous infestation of host chilli plants by the green peach aphid (Myzus persicae) on the olfactory behavioural response of B. tabaci, using free-choice bioassay with a Y-tube olfactometer. We analysed volatil...

  10. The entomopathogenic fungal endophytes Purpureocillium lilacinum (formerly Paecilomyces lilacinus and Beauveria bassiana negatively affect cotton aphid reproduction under both greenhouse and field conditions.

    Directory of Open Access Journals (Sweden)

    Diana Castillo Lopez

    Full Text Available The effects of two entomopathogenic fungal endophytes, Beauveria bassiana and Purpureocillium lilacinum (formerly Paecilomyces lilacinus, were assessed on the reproduction of cotton aphid, Aphis gossypii Glover (Homoptera:Aphididae, through in planta feeding trials. In replicate greenhouse and field trials, cotton plants (Gossypium hirsutum were inoculated as seed treatments with two concentrations of B. bassiana or P. lilacinum conidia. Positive colonization of cotton by the endophytes was confirmed through potato dextrose agar (PDA media plating and PCR analysis. Inoculation and colonization of cotton by either B. bassiana or P. lilacinum negatively affected aphid reproduction over periods of seven and 14 days in a series of greenhouse trials. Field trials were conducted in the summers of 2012 and 2013 in which cotton plants inoculated as seed treatments with B. bassiana and P. lilacinum were exposed to cotton aphids for 14 days. There was a significant overall effect of endophyte treatment on the number of cotton aphids per plant. Plants inoculated with B. bassiana had significantly lower numbers of aphids across both years. The number of aphids on plants inoculated with P. lilacinum exhibited a similar, but non-significant, reduction in numbers relative to control plants. We also tested the pathogenicity of both P. lilacinum and B. bassiana strains used in the experiments against cotton aphids in a survival experiment where 60% and 57% of treated aphids, respectively, died from infection over seven days versus 10% mortality among control insects. Our results demonstrate (i the successful establishment of P. lilacinum and B. bassiana as endophytes in cotton via seed inoculation, (ii subsequent negative effects of the presence of both target endophytes on cotton aphid reproduction using whole plant assays, and (iii that the P. lilacinum strain used is both endophytic and pathogenic to cotton aphids. Our results illustrate the potential of

  11. Quantification of sugarcane yellow leaf virus in sugarcane following transmission through aphid vector, Melanaphis sacchari.

    Science.gov (United States)

    Chinnaraja, C; Viswanathan, R

    2015-12-01

    Yellow leaf caused by Sugarcane yellow leaf virus (SCYLV) is a serious constraint to sugarcane production in India and currently the disease epidemics occur on many of the susceptible varieties under field conditions. Studies were conducted on the virus transmission by sugarcane aphid Melanaphis sacchari in sugarcane by inoculating virus-free meristem derived from micro- propagated plants of sugarcane cv Co 86032 with viruliferous aphids. Virus transmission was confirmed through RT-PCR assays and subsequently SCYLV population was established through RT-qPCR. A maximum of 22.3 × 10(3), 3.16 × 10(6) and 4.78 × 10(6) copies of SCYLV-RNA targets were recorded in the plants after 7, 180 and 300 days, respectively. This study showed that the aphid species M. sacchari acts as an effective vector of SCYLV. The relative standard curve method in RT-qPCR efficiently detected the increment in SCYLV copy numbers in sugarcane following transmission through M. sacchari. PMID:26645033

  12. Comparative analysis of mitochondrial genomes of five aphid species (Hemiptera: Aphididae and phylogenetic implications.

    Directory of Open Access Journals (Sweden)

    Yuan Wang

    Full Text Available Insect mitochondrial genomes (mitogenomes are of great interest in exploring molecular evolution, phylogenetics and population genetics. Only two mitogenomes have been previously released in the insect group Aphididae, which consists of about 5,000 known species including some agricultural, forestry and horticultural pests. Here we report the complete 16,317 bp mitogenome of Cavariella salicicola and two nearly complete mitogenomes of Aphis glycines and Pterocomma pilosum. We also present a first comparative analysis of mitochondrial genomes of aphids. Results showed that aphid mitogenomes share conserved genomic organization, nucleotide and amino acid composition, and codon usage features. All 37 genes usually present in animal mitogenomes were sequenced and annotated. The analysis of gene evolutionary rate revealed the lowest and highest rates for COI and ATP8, respectively. A unique repeat region exclusively in aphid mitogenomes, which included variable numbers of tandem repeats in a lineage-specific manner, was highlighted for the first time. This region may have a function as another origin of replication. Phylogenetic reconstructions based on protein-coding genes and the stem-loop structures of control regions confirmed a sister relationship between Cavariella and pterocommatines. Current evidence suggest that pterocommatines could be formally transferred into Macrosiphini. Our paper also offers methodological instructions for obtaining other Aphididae mitochondrial genomes.

  13. Genetic and Association Mapping Study of English Grain Aphid Resistance and Tolerance in Bread Wheat Germplasm

    Institute of Scientific and Technical Information of China (English)

    LI Feng-qi; PENG Jun-hua

    2014-01-01

    English grain aphid (EGA) is a destructive insect pest of wheat. To identify the loci associated with EGA resistance and tolerance, 70 bread wheat accessions mainly from central Asia were evaluated for EGA resistance and tolerance traits at two locations, and genotyped with 51 SSR markers. Totally, three accessions showed high or moderate levels resistance and 17 genotypes displayed highly or moderately tolerate to EGA. Genetic diversity of these lines was investigated also. After 97 SSR loci which evenly covered all wheat chromosomes were scanned for association, four SSR loci were signiifcantly associated with EGA resistance and four with EGA tolerance. After association analysis was conducted with dynamic aphid densities, we found four loci Xgwm192b, Xgwm391, Xbarc98, and Xgwm613b were detected continuously at different growing stages of wheat. In addition, the loci of EGA resistance/tolerance and Russian wheat aphid resistance were compared. The results generated in this study would be helpful for utilization of the EGA resistance/tolerance germplasm, and for development of mapping populations in EGA resistance breeding programs.

  14. Polymorphisms in salivary-gland transcripts of Russian wheat aphid biotypes 1 and 2

    Institute of Scientific and Technical Information of China (English)

    Feng Cui; C.Michael Smith; John Reese; Owain Edwards; Gerald Reeck

    2012-01-01

    The Russian wheat aphid (RWA),Diuraphis noxia (Mordvilko) (Homoptera:Aphididae),is a major pest of small grains.As with plant-feeding aphids in general,the interaction between RWA and host plants is governed,on the insect side,by proteins and enzymes in saliva.In this work,we examined sequence variations in transcripts encoding proteins and enzymes of RWA salivary glands.We conducted reverse transcription - polymerase chain reaction in RWA biotypes 1 and 2 using primers derived from pea aphid orthoiogs,and cloned regions of 17 putative salivary gland transcripts.For four of the transcripts,we observed no difference in sequences between the two biotypes.For the other 13 transcripts,for example,the transcripts encoding sucrase,trehalase and protein C002,large amount of variations,both within each biotype and between the two biotypes,were observed.Usually the two biotypes shared only one variant,which was typically the most common variant in both biotypes.Most of the transcripts had more non-synonymous than synonymous codon changes among their variants.Our results offer possible molecular markers for distinguishing the two biotypes and insights into their evolution.

  15. Zinc and cadmium accumulation in cabbage aphid(Brevicoryne brassicae)host plants and developmental instability

    Institute of Scientific and Technical Information of China (English)

    Gazi G(o)rür

    2009-01-01

    Developmental instability in morphological characters can occur during individual development due to various environmental stresses.Fluctuating asymmetry (FA)is often used as a measurement of developmental instability.but within-environment variation(cve)is also considered an indicator of developmental instability.Cabbage aphid nated cabbage and radish plants.Developmental instability indicators were measured and their relations with fitness were explored.Results revealed that cabbage aphids exposed to Cd and Zn displayed considerable developmental instability,particularly fluctuating asymmetry.Differences in developmental instability between the two metals were also detected,as well as differences between the two developmental instability measurements.For almost all measured traits.FA was greater on Cd-and Zn-contaminated compared to non-contaminated host plants.In contrast.CV of some traits was greater on non-contami-nated host plants,yet for Otller traits CV Was greater on contaminated host plants.There were also non-significant inverse relationships between FA and fitness of cabbage aphid populations.Due to weak correlations between FA and different patterns of two developmental instability measurements,this study does not support the hypothesis that developmental instability is a useful bioindicator of environmental quality.

  16. Quantification of sugarcane yellow leaf virus in sugarcane following transmission through aphid vector, Melanaphis sacchari.

    Science.gov (United States)

    Chinnaraja, C; Viswanathan, R

    2015-12-01

    Yellow leaf caused by Sugarcane yellow leaf virus (SCYLV) is a serious constraint to sugarcane production in India and currently the disease epidemics occur on many of the susceptible varieties under field conditions. Studies were conducted on the virus transmission by sugarcane aphid Melanaphis sacchari in sugarcane by inoculating virus-free meristem derived from micro- propagated plants of sugarcane cv Co 86032 with viruliferous aphids. Virus transmission was confirmed through RT-PCR assays and subsequently SCYLV population was established through RT-qPCR. A maximum of 22.3 × 10(3), 3.16 × 10(6) and 4.78 × 10(6) copies of SCYLV-RNA targets were recorded in the plants after 7, 180 and 300 days, respectively. This study showed that the aphid species M. sacchari acts as an effective vector of SCYLV. The relative standard curve method in RT-qPCR efficiently detected the increment in SCYLV copy numbers in sugarcane following transmission through M. sacchari.

  17. Sipha maydis: distribution and host range of a new aphid pest of winter cereals in Argentina.

    Science.gov (United States)

    Corrales, C E; Castro, A M; Ricci, M; Dixon, A F G

    2007-12-01

    Sipha maydis (Passerini) is a new aphid pest of cereals and cultivated and wild grasses in Argentina. This species was recently introduced into America, and nothing is known of its distribution or host range in South America. A better understanding of its biology is likely to facilitate control. This article records 1) the distribution and 2) the host range of S. maydis in Argentina. Over the period 2004-2006 samples were collected from 32 populations at several localities in Argentina. The number of S. maydis, accompanying aphid species, and the host from which they were collected were recorded. The distribution of S. maydis ranged from 32 degrees 52' to 42 degrees 03' S, and from 57 degrees 41' to 71 degrees 24' W, bounded by isothermals 18 and 10 degrees C and isohyets 200-400 and Sorghum halepense (L.) Pers. No aphids were found on maize, Zea mays L. Most of the damage to winter cereal crops occurred at the seedling stage in early autumn and of adult plants when infestations occurred in late spring. In the 4 yr after the first record of S. maydis in Argentina, it colonized a huge area similar to that colonized by Diuraphis noxia (Mordvilko) in 10 yr. The wide range of regions, hosts and climatic conditions this species is adapted to is likely to make the control of this pest very difficult.

  18. Catastrophic behavior of aphid population dynamics: An analysis of swallowtail model

    Directory of Open Access Journals (Sweden)

    Mkdk Piyaratne

    2014-09-01

    Full Text Available Catastrophe phenomena are frequent in insect ecology, especially in aphid populations. Complexity of this phenomenon urges different modeling frameworks other than traditional methodologies to understand the trajectories of their behavior. Situations like this can be best handled using catastrophe theory. A few numbers of experiments have been conducted to develop catastrophe models in insect ecology, especially for aphids, and most of them are based on cusp catastrophe theory which is a lower dimensional model. However few attempts using higher dimensional models such as swallowtail or butterfly theory to analyze aphid population dynamics are also exist. In this paper we tried to analyze a recently developed higher dimensional catastrophe theory model (APHIDSim in order to identify catastrophe regions, and used independent data to identify if catastrophic behavior is observed in the data and consequently to further verify the model. Here we found that identifying catastrophe regions is possible using catastrophe theory model, and it can be used to analyze catastrophes in insect ecology by graphically interpreting the simulated results. Increasing of insect population is intrinsically catastrophic and catastrophes (jumps occur between states even if the driving variables still change smoothly. The results further verified the previously developed model, and we suggest that insect management program developers should consider this phenomenon when they design the management strategies for insect controlling.

  19. Nitrogen deficiency in barley (Hordeum vulgare) seedlings induces molecular and metabolic adjustments that trigger aphid resistance.

    Science.gov (United States)

    Comadira, Gloria; Rasool, Brwa; Karpinska, Barbara; Morris, Jenny; Verrall, Susan R; Hedley, Peter E; Foyer, Christine H; Hancock, Robert D

    2015-06-01

    Agricultural nitrous oxide (N2O) pollution resulting from the use of synthetic fertilizers represents a significant contribution to anthropogenic greenhouse gas emissions, providing a rationale for reduced use of nitrogen (N) fertilizers. Nitrogen limitation results in extensive systems rebalancing that remodels metabolism and defence processes. To analyse the regulation underpinning these responses, barley (Horedeum vulgare) seedlings were grown for 7 d under N-deficient conditions until net photosynthesis was 50% lower than in N-replete controls. Although shoot growth was decreased there was no evidence for the induction of oxidative stress despite lower total concentrations of N-containing antioxidants. Nitrogen-deficient barley leaves were rich in amino acids, sugars and tricarboxylic acid cycle intermediates. In contrast to N-replete leaves one-day-old nymphs of the green peach aphid (Myzus persicae) failed to reach adulthood when transferred to N-deficient barley leaves. Transcripts encoding cell, sugar and nutrient signalling, protein degradation and secondary metabolism were over-represented in N-deficient leaves while those associated with hormone metabolism were similar under both nutrient regimes with the exception of mRNAs encoding proteins involved in auxin metabolism and responses. Significant similarities were observed between the N-limited barley leaf transcriptome and that of aphid-infested Arabidopsis leaves. These findings not only highlight significant similarities between biotic and abiotic stress signalling cascades but also identify potential targets for increasing aphid resistance with implications for the development of sustainable agriculture.

  20. Erwinia iniecta sp. nov., isolated from Russian wheat aphid (Diuraphis noxia).

    Science.gov (United States)

    Campillo, Tony; Luna, Emily; Portier, Perrine; Fischer-Le Saux, Marion; Lapitan, Nora; Tisserat, Ned A; Leach, Jan E

    2015-10-01

    Short, Gram-negative-staining, rod-shaped bacteria were isolated from crushed bodies of Russian wheat aphid [Diuraphis noxia (Kurdjumov)] and artificial diets after Russian wheat aphid feeding. Based on multilocus sequence analysis involving the 16S rRNA, atpD, infB, gyrB and rpoB genes, these bacterial isolates constitute a novel clade in the genus Erwinia, and were most closely related to Erwinia toletana. Representative distinct strains within this clade were used for comparisons with related species of Erwinia. Phenotypic comparisons using four distinct strains and average nucleotide identity (ANI) measurements using two distinct draft genomes revealed that these strains form a novel species within the genus Erwinia. The name Erwinia iniecta sp. nov. is proposed, and strain B120T ( = CFBP 8182T = NCCB 100485T) was designated the type strain. Erwinia iniecta sp. nov. was not pathogenic to plants. However, virulence to the Russian wheat aphid was observed.

  1. Nitrogen deficiency in barley (Hordeum vulgare) seedlings induces molecular and metabolic adjustments that trigger aphid resistance.

    Science.gov (United States)

    Comadira, Gloria; Rasool, Brwa; Karpinska, Barbara; Morris, Jenny; Verrall, Susan R; Hedley, Peter E; Foyer, Christine H; Hancock, Robert D

    2015-06-01

    Agricultural nitrous oxide (N2O) pollution resulting from the use of synthetic fertilizers represents a significant contribution to anthropogenic greenhouse gas emissions, providing a rationale for reduced use of nitrogen (N) fertilizers. Nitrogen limitation results in extensive systems rebalancing that remodels metabolism and defence processes. To analyse the regulation underpinning these responses, barley (Horedeum vulgare) seedlings were grown for 7 d under N-deficient conditions until net photosynthesis was 50% lower than in N-replete controls. Although shoot growth was decreased there was no evidence for the induction of oxidative stress despite lower total concentrations of N-containing antioxidants. Nitrogen-deficient barley leaves were rich in amino acids, sugars and tricarboxylic acid cycle intermediates. In contrast to N-replete leaves one-day-old nymphs of the green peach aphid (Myzus persicae) failed to reach adulthood when transferred to N-deficient barley leaves. Transcripts encoding cell, sugar and nutrient signalling, protein degradation and secondary metabolism were over-represented in N-deficient leaves while those associated with hormone metabolism were similar under both nutrient regimes with the exception of mRNAs encoding proteins involved in auxin metabolism and responses. Significant similarities were observed between the N-limited barley leaf transcriptome and that of aphid-infested Arabidopsis leaves. These findings not only highlight significant similarities between biotic and abiotic stress signalling cascades but also identify potential targets for increasing aphid resistance with implications for the development of sustainable agriculture. PMID:26038307

  2. Effect of heavy metals on growth and heavy metal content of Allium porrum L. and Pisum sativum L

    Energy Technology Data Exchange (ETDEWEB)

    Gruenhage, L.; Jaeger, H.J.

    1985-01-01

    The effects of cadmium, lead, zinc and copper, singly and in combination, on yield, heavy metal content and the mineral composition of Allium porrum L. and Pisum sativum L. have been investigated. The Cd, Pb, Zn and Cu concentrations of shoots and roots of Allium porrum increased with increasing heavy metal contamination of soil. However, no visible symptoms of heavy metal toxicity were recognized. The dry matter production was reduced as a function of heavy metal concentration and combination. The mechanisms of combinations were mostly synergistic. The correlation between pollutant contents (nmol/shoot) and yield was higher than the correlation between heavy metal concentrations of soil or shoots (ppm) and yield. Results of regression analyses showed that the inhibition of copper translocation caused by Cd, Pb and Zn was responsible for the yield depressions. The antagonism between Cd and N-deficiency showed that the level of N-supply was without negative effects on yield depressions of Pisum sativum caused by Cd. In contrast to this, the N-form played an important role in Cd-toxicity as the synergism between Cd and NH4 illustrated. K-deficiency as well as acidic nutrient solution (pH=4) diminished the root/shoot-barrier for Cd and therefore Cd-translocation from roots to shoots increased. Concerning calcium, magnesium and iron the decrease of ion uptake caused by Cd was statistically significant higher than yield depression.

  3. Genetic diversity and population structure of Pisum sativum accessions for marker-trait association of lipid content

    Directory of Open Access Journals (Sweden)

    Sajjad Ahmad

    2015-06-01

    Full Text Available Field pea (Pisum sativum L. is an important protein-rich pulse crop produced globally. Increasing the lipid content of Pisum seeds through conventional and contemporary molecular breeding tools may bring added value to the crop. However, knowledge about genetic diversity and lipid content in field pea is limited. An understanding of genetic diversity and population structure in diverse germplasm is important and a prerequisite for genetic dissection of complex characteristics and marker-trait associations. Fifty polymorphic microsatellite markers detecting a total of 207 alleles were used to obtain information on genetic diversity, population structure and marker-trait associations. Cluster analysis was performed using UPGMA to construct a dendrogram from a pairwise similarity matrix. Pea genotypes were divided into five major clusters. A model-based population structure analysis divided the pea accessions into four groups. Percentage lipid content in 35 diverse pea accessions was used to find potential associations with the SSR markers. Markers AD73, D21, and AA5 were significantly associated with lipid content using a mixed linear model (MLM taking population structure (Q and relative kinship (K into account. The results of this preliminary study suggested that the population could be used for marker-trait association mapping studies.

  4. Isoenzymes of superoxide dismutase in nodules of Phaseolus vulgaris L. , Pisum sativum L. , and Vigna unguiculata (L. ) Walp

    Energy Technology Data Exchange (ETDEWEB)

    Becana, M.; Paris, F.J.; Sandalio, L.M.; Del Rio, L.A. (IRNA, Salamanca (Spain) Unidad de Bioquimica Vegetal, Granada (Spain))

    1989-08-01

    The activity and isozymic composition of superoxide dismutase were determined in nodules of Phaseolus vulgaris L., Pisum sativum L., and Vigna unguiculata (L.) Walp. A Mn-SOD was present in Rhizobium and two in Bradyrhizobium and bacteroids. Nodule mitochondria from all three legume species had a single Mn-SOD with similar relative mobility, whereas the cytosol contained several CuZn-SODs: two in Phaseolus and Pisum, and four in Vigna. In the cytoplasm of V. unguiculata nodules, a Fe-containing SOD was also present, with an electrophoretic mobility between those of CuZn- and Mn-SODs, and an estimated molecular weight of 57,000. Total SOD activity of the soluble fraction of host cells, expressed on a nodule fresh weight basis, exceeded markedly that of bacteroids. Likewise, specific SOD activities of free-living bacteria were superior or equal to those of their symbiotic forms. Soluble extracts of bacteria and bacteroids did not show peroxidase activity, but the nodule cell cytoplasm contained diverse peroxidase isozymes which were readily distinguishable from leghemoglobin components by electrophoresis. Data indicated that peroxidases and leghemoglobins did not significantly interfere with SOD localization on gels. Treatment with chloroform-ethanol scarcely affected the isozymic pattern of SODs and peroxidases, and had limited success in the removal of leghemoglobin.

  5. Genetic diversity and population structure of Pisum sativum accessions for marker-trait association of lipid content

    Institute of Scientific and Technical Information of China (English)

    Sajjad; Ahmad; Simerjeet; Kaur; Neil; Dylan; Lamb-Palmer; Mark; Lefsrud; Jaswinder; Singh

    2015-01-01

    Field pea(Pisum sativum L.) is an important protein-rich pulse crop produced globally. Increasing the lipid content of Pisum seeds through conventional and contemporary molecular breeding tools may bring added value to the crop. However, knowledge about genetic diversity and lipid content in field pea is limited. An understanding of genetic diversity and population structure in diverse germplasm is important and a prerequisite for genetic dissection of complex characteristics and marker-trait associations. Fifty polymorphic microsatellite markers detecting a total of 207 alleles were used to obtain information on genetic diversity, population structure and marker-trait associations. Cluster analysis was performed using UPGMA to construct a dendrogram from a pairwise similarity matrix. Pea genotypes were divided into five major clusters. A model-based population structure analysis divided the pea accessions into four groups. Percentage lipid content in 35 diverse pea accessions was used to find potential associations with the SSR markers. Markers AD73, D21, and AA5 were significantly associated with lipid content using a mixed linear model(MLM) taking population structure(Q) and relative kinship(K) into account. The results of this preliminary study suggested that the population could be used for marker-trait association mapping studies.

  6. Batch Scale Removal of an Organic Pollutant Amaranth Dye from Aqueous Solution using Pisum sativum Peels and Arachis hypogaea Shells as Adsorbents

    International Nuclear Information System (INIS)

    The goal of this study was to utilize low cost and environmentally friendly adsorbents for batch scale removal of Amaranth dye from aqueous medium. Peels of Pisum sativum (Pea) and Arachis hypogaea (Peanut) were utilized to investigate their dye removing capacity. The optimized adsorption conditions for Pisum sativum (P.S.P) and Arachis hypogaea (A.H.S) were: adsorbent dose; 0.6 and 0.4 g, contact time; 45 and 10 minutes, pH; 2.0 for both, agitation speed; 150 and 100 rpm and temperature; 60 and 50 degree C for P.S.P and A.H.S respectively. The adsorption data well suited to Langmuir isotherm. Maximum adsorption capacities were found to be 144.93 and 10.53 mg/g for P.S.P and A.H.S respectively. Feasibility of the process was indicated by negative values of thermodynamic parameters delta G/sup 0/ for both adsorbents. Kinetic studies indicated that adsorption of Amaranth dye from aqueous medium by Pisum sativum peels and Arachis hypogaea shells followed pseudo-seconder order kinetics. It was concluded that Pisum sativum peels are more effective adsorbent for removal of Amaranth from aqueous solution as compared to Arachis hypogaea shells. (author)

  7. Evaluation of expression stability of candidate references genes among green and yellow pea cultivars (Pisum sativum L.) subjected to abiotic and biotic stress

    Science.gov (United States)

    Dry pea (Pisum sativum) is grown as human and animal feed throughout the world. Large yield losses in pea due to biotic and abiotic stresses compel an improved understanding of mechanisms of stress tolerance and genetic determinants conditioning these tolerances. The availability of stably expressed...

  8. Aphid fecundity and grassland invasion: invader life history is the key.

    Science.gov (United States)

    Borer, Elizabeth T; Adams, Vincent T; Engler, Gareth A; Adams, Autumn L; Schumann, Canan B; Seabloom, Eric W

    2009-07-01

    Loss or gain of pathogens can determine the trajectory of biological invasions, and invasion by novel hosts also can alter pathogen dynamics to facilitate invasion. Recent empirical and theoretical work has implicated infection by barley and cereal yellow dwarf viruses (B/CYDV), a group of generalist pathogens of the Poaceae family (grasses), as a necessary precursor to the invasion of over 9 million hectares of California's perennial grasslands by exotic annual grasses. The mechanism underlying this pathogen-mediated invasion hypothesis is elevated vector fecundity on exotic annual grasses. While empirical evidence supports this hypothesis, the links between aphid fecundity, host identity, and host resource supply have not been thoroughly assessed. We performed field and laboratory experiments to examine the fecundity and preference responses of three of the most common aphid vectors of B/CYDV, Rhopalosiphum padi (L.), R. maidis (Fitch), and Sitobion avenae (Fab.), to a combination of host life history (annual and perennial), host provenance (native and exotic), and nutrient supply (mineral N and P fertilization), controlling for host phylogenetic lineage. Aphids consistently had higher fecundity on annual grasses than perennials, regardless of host provenance, age, or nutrient fertilization. In addition, aphids preferentially colonized annual hosts when offered a choice among host species. Multi-generation studies have found that nutrient addition affects both host quality and composition in natural communities; our experimental results indicate that the indirect effects of nutrient fertilization in determining host community composition are of more importance than are the direct effects on host quality to aphid population dynamics. To summarize the applications of our results, we demonstrate that, in contrast to the current focus on the qualitative differences between invaders and natives, the impact of invasive exotic grasses is not due to host provenance, per

  9. Female-induced increase of host-plant volatiles enhance specific attraction of aphid male Dysaphis plantaginea (Homoptera: Aphididae) to the sex pheromone

    NARCIS (Netherlands)

    Tol, van R.W.H.M.; Helsen, H.H.M.; Griepink, F.C.; Kogel, de W.J.

    2009-01-01

    All aphid species studied so far share the same sex pheromone components, nepetalactol and nepetalactone. Variation by different enantiomers and blends of the two components released by different aphid species are limited and can only partially explain species-specific attraction of males to females

  10. Migration and population genetics of the grain aphid Macrosiphum miscanti (Takahashi) in relation to the geographic distance and gene flow

    Institute of Scientific and Technical Information of China (English)

    GUO Wei; SHEN Zuorui; LI Zhihong; GAO Lingwang

    2005-01-01

    The population genetics of the grain aphid Macrosiphum miscanti (Takahashi) is analyzed by microsatellite markers.Samples collected from 15 locations in China have been examined at 5 polymorphic microsatellite loci. Overall, genetic diversity displays a relation between the migration and gene flow in the grain aphid: a free and frequent gene flow is found in the eastern populations, and gene isolation occurs in the two western populations, especially Datong population and Guiyang population. The natural barriers may present an insurmountable obstacle preventing gene flow and aphid migration. However, a spatial genetic differentiation between populations is correlated with their geographical separation, indicating the geographic differentiation may play an important role in shaping the genetic structure of M. miscanti populations. In addition, most populations of grain aphids are out of Hardy-Weinberg equilibrium and there is heterozygote deficit. Based on F statistics, the average genetic differentiation among different geographical populations is relatively low. It seems that the long distance migration of the grain aphid may enhance gene flow and decrease genetic differentiation among different populations.

  11. Genetic structure of the aphid, Chaetosiphon fragaefolii, and its role as a vector of the Strawberry Yellow Edge Virus to a native strawberry, Fragaria chiloensis in Chile.

    Science.gov (United States)

    Lavandero, Blas; Rojas, Pamela; Ramirez, Claudio C; Salazar, Marcela; Caligari, Peter D S

    2012-01-01

    The monoecious anholocyclical aphid, Chaetosiphon fragaefolii (Cockerell) (Homoptera: Aphididae), was collected on a native strawberry, Fragaria chiloensis (L.) Duchesne (Rosales: Rosaceae) from different sites in Chile. The presence of this aphid was recorded during two consecutive years. F. chiloensis plants were collected from seven natural and cultivated growing areas in central and southern Chile. Aphids were genotyped by cross-species amplification of four microsatellite loci from other aphid species. In addition, the aphid borne virus Strawberry mild yellow edge virus was confirmed in F. chiloensis plants by double-antibody sandwich ELISA and RT-PCR. Genetic variability and structure of the aphid populations was assessed from the geo-referenced individuals through AMOVA and a Bayesian assignment test. The presence of C. fragaefolii, during the two-year study was detected in only four of the seven sites (Curepto, Contulmo, Chilián and Cucao). Genetic variation among these populations reached 19% of the total variance. When assigning the individuals to groups, these were separated in three genetic clusters geographically disjunct. Of the seven sampled sites, six were positive for the virus by RT-PCR, and five by double-antibody sandwich ELISA . The incidence of the virus ranged from 0-100%. Presence of the virus corresponded with the presence of the aphid in all but two sites (Chilian and Vilches). The greatest incidence of Strawberry mild yellow edge virus was related to the abundance of aphids. On the other hand, sequences of the coat protein gene of the different virus samples did not show correspondence with either the genetic groups of the aphids or the sampling sites. The genetic structure of aphids could suggest that dispersal is mainly through human activities, and the spread to natural areas has not yet occurred on a great scale.

  12. Genetic structure of the aphid, Chaetosiphon fragaefolii, and its role as a vector of the Strawberry Yellow Edge Virus to a native strawberry, Fragaria chiloensis in Chile.

    Science.gov (United States)

    Lavandero, Blas; Rojas, Pamela; Ramirez, Claudio C; Salazar, Marcela; Caligari, Peter D S

    2012-01-01

    The monoecious anholocyclical aphid, Chaetosiphon fragaefolii (Cockerell) (Homoptera: Aphididae), was collected on a native strawberry, Fragaria chiloensis (L.) Duchesne (Rosales: Rosaceae) from different sites in Chile. The presence of this aphid was recorded during two consecutive years. F. chiloensis plants were collected from seven natural and cultivated growing areas in central and southern Chile. Aphids were genotyped by cross-species amplification of four microsatellite loci from other aphid species. In addition, the aphid borne virus Strawberry mild yellow edge virus was confirmed in F. chiloensis plants by double-antibody sandwich ELISA and RT-PCR. Genetic variability and structure of the aphid populations was assessed from the geo-referenced individuals through AMOVA and a Bayesian assignment test. The presence of C. fragaefolii, during the two-year study was detected in only four of the seven sites (Curepto, Contulmo, Chilián and Cucao). Genetic variation among these populations reached 19% of the total variance. When assigning the individuals to groups, these were separated in three genetic clusters geographically disjunct. Of the seven sampled sites, six were positive for the virus by RT-PCR, and five by double-antibody sandwich ELISA . The incidence of the virus ranged from 0-100%. Presence of the virus corresponded with the presence of the aphid in all but two sites (Chilian and Vilches). The greatest incidence of Strawberry mild yellow edge virus was related to the abundance of aphids. On the other hand, sequences of the coat protein gene of the different virus samples did not show correspondence with either the genetic groups of the aphids or the sampling sites. The genetic structure of aphids could suggest that dispersal is mainly through human activities, and the spread to natural areas has not yet occurred on a great scale. PMID:23438175

  13. Species composition of aphid vectors (Hemiptera: Aphididae) of barley yellow dwarf virus and cereal yellow dwarf virus in Alabama and western Florida.

    Science.gov (United States)

    Hadi, Buyung A R; Flanders, Kathy L; Bowen, Kira I; Murphy, John F; Halbert, Susan E

    2011-08-01

    Yellow dwarf is a major disease problem of wheat, Triticum aestivum L., in Alabama and is estimated to cause yield loss of 21-42 bu/acre. The disease is caused by a complex of viruses comprising several virus species, including Barley yellow dwarf virus-PAV and Cereal yellow dwarf virus-RPV. Several other strains have not yet been classified into a specific species. The viruses are transmitted exclusively by aphids (Hemiptera:Aphididae). Between the 2005 and 2008 winter wheat seasons, aphids were surveyed in the beginning of each planting season in several wheat plots in Alabama and western Florida Collected aphids were identified and bioassayed for their yellow dwarf virus infectivity. This survey program was designed to identify the aphid species that serve as fall vectors of yellow dwarf virus into winter wheat plantings. From 2005 to 2008, bird cherry-oat aphid, Rhopalosiphum padi (L.); rice root aphid, Rhopalosiphum rufiabdominale (Sasaki); and greenbug, Schizaphis graminum (Rondani), were found consistently between October and December. The species of aphids and their timing of appearance in wheat plots were consistent with flight data collected in North Alabama between 1996 and 1999. Both R. padi and R. rufiabdominale were found to carry and transmit Barley yellow dwarf virus-PAV and Cereal yellow dwarf virus-RPV. The number of collected aphids and proportion of viruliferous aphids were low. Although this study has shown that both aphids are involved with introduction of yellow dwarf virus to winter wheat in Alabama and western Florida, no conclusions can be made as to which species may be the most important vector of yellow dwarf virus in the region. PMID:21882679

  14. Exposure to bacterial signals does not alter pea aphids' survival upon a second challenge or investment in production of winged offspring.

    Directory of Open Access Journals (Sweden)

    Bas ter Braak

    Full Text Available Pea aphids have an obligate nutritional symbiosis with the bacteria Buchneraaphidicola and frequently also harbor one or more facultative symbionts. Aphids are also susceptible to bacterial pathogen infections, and it has been suggested that aphids have a limited immune response towards such pathogen infections compared to other, more well-studied insects. However, aphids do possess at least some of the genes known to be involved in bacterial immune responses in other insects, and immune-competent hemocytes. One possibility is that immune priming with microbial elicitors could stimulate immune protection against subsequent bacterial infections, as has been observed in several other insect systems. To address this hypothesis we challenged aphids with bacterial immune elicitors twenty-four hours prior to live bacterial pathogen infections and then compared their survival rates to aphids that were not pre-exposed to bacterial signals. Using two aphid genotypes, we found no evidence for immune protection conferred by immune priming during infections with either Serratia marcescens or with Escherichia coli. Immune priming was not altered by the presence of facultative, beneficial symbionts in the aphids. In the absence of inducible immune protection, aphids may allocate energy towards other defense traits, including production of offspring with wings that could escape deteriorating conditions. To test this, we monitored the ratio of winged to unwinged offspring produced by adult mothers of a single clone that had been exposed to bacterial immune elicitors, to live E. coli infections or to no challenge. We found no correlation between immune challenge and winged offspring production, suggesting that this mechanism of defense, which functions upon exposure to fungal pathogens, is not central to aphid responses to bacterial infections.

  15. Association of aphid life stages using DNA sequences:A case study of tribe Eriosomatini(Hemiptera:Aphididae:Pemphiginae)

    Institute of Scientific and Technical Information of China (English)

    He-Cai Zhang; Dong Zhang; Ge-Xia Qiao

    2008-01-01

    Association of aphid 1ife stages based on a portion of COI,sequcnce was applied in Eriosomatini.Tllree aphid specimens,nos.17496,19265a,and 19265b collected on Gramineae roots all clustered with tetraneura chinensis Mordvilko with strong support.The average pairwise p-distance among the four taxa was 0.001(range,0.000-0.002),and that among all the ingroup taxa was 0.065(range.0.000-0.141).This indicated that nos.17496 and 1 9265 b were the secondary.host morohs of T. chinensis.In this paper the secondary host morph of T.chinensis iS described for the first time.Wim the identification of more species'secondary-host morphs,aphids identification based on this morph will be made easily.

  16. Influence of selected plant amines on probing behaviour of bird cherry-oat aphid (Rhopalosiphum padi L.).

    Science.gov (United States)

    Sempruch, C; Goławska, S; Osiński, P; Leszczyński, B; Czerniewicz, P; Sytykiewicz, H; Matok, H

    2016-06-01

    The study aimed to quantify the influence of common plant polyamines and tyramine on probing behaviour in the bird cherry-oat aphid (Rhopalosiphum padi L.). Electrical penetration graphs (DC) were used to monitor the probing and feeding behaviour of R. padi exposed to the amines agmatine, cadaverine, putrescine, spermidine, spermine and tyramine. The study results showed that the analyzed amines tended to shorten the stylet activity of aphids in the gels (as indicated by the g-C pattern), prolong the duration of non-probing behaviour (g-np pattern) and decrease salivation into the gels (g-E1pattern) and ingestion from the gels (g-G pattern). The 10 mM concentration of the studied amines, especially cadaverine, reduced or completely inhibited aphid ingestion. The obtained results demonstrate that plant amines participate in plant defence responses to R. padi through disturbance of its probing behaviour and the intensity of such effects is concentration dependent. PMID:26898153

  17. Assessment of Sublethal and Transgenerational Effects of Pirimicarb on the Wheat Aphids Rhopalosiphum padi and Sitobion avenae

    Science.gov (United States)

    Desneux, Nicolas; Han, Peng; Gao, Xiwu

    2015-01-01

    The wheat aphids, Rhopalosiphum padi (Linnaeus) and Sitobion avenae (Fabricius), are key pests on wheat crops worldwide. Management practices rely primarily on insecticides. The pirimicarb (carbamate) is used extensively as an effective insecticide to control these two aphids. In addition to the mortality caused by pirimicarb, various sublethal effects may occur in aphids when exposed to low lethal or sublethal doses. Understanding the general effect of pirimicarb on aphids could help increasing rational use of this insecticide. Under laboratory conditions, we assessed the sublethal effects of a low lethal concentration of pirimicarb (LC25) on biological traits and acetylcholinesterase (AChE) activity of R. padi and S. avenae. Both direct and transgenerational effects, i.e. on parent and the F1 generations were assessed, respectively. We found that R. padi and S. avenae responded differentially to the LC25 of pirimicarb. The parent generation of R. padi showed a 39% decrease in fecundity and multiple transgenerational effects were observed in the F1 generation; overall juvenile development, reproductive period, adult longevity and lifespan were longer than those of the control group. By contrast, LC25 of pirimicarb showed almost no effects on S. avenae biological traits in both the parent and F1 generations; only the pre-reproductive duration was reduced in F1 generations. Demographic parameter estimates (e.g. rm) showed similar trend, i.e. significant negative effect on R. padi population growth and no effect on S. avenae. However, AChE activity decreased in both R. padi and S. avenae treated by the LC25 of pirimicarb. We demonstrated sublethal and transgenerational effects of pirimicarb in the two wheat aphid species; it hinted at the importance of considering sublethal effects (including hormesis) of pirimicarb for optimizing Integrated Pest Management (IPM) of wheat aphids. PMID:26121265

  18. The effects of monitoring the abundance and species composition of aphids as virus vectors on seed potato production in Serbia

    Directory of Open Access Journals (Sweden)

    Drago Milošević

    2014-03-01

    Full Text Available Aphids are the most important vectors of potato viruses during the crop’s growing season. The most widespread and damaging viruses, the potato virus Y and potato leaf roll virus, are transmitted by aphids in non-persistent and persistent manner, respectively. The two viruses cause the greatest concern of potato producers and a great constraint to seed potato production in Serbia, the region and across the world. Potato virus Y is particularly harmful, given its distribution and spreading rate. Seed potato production systems under well-managed conditions involve a series of virus control measures, including the monitoring of outbreaks of winged aphids, their abundance and species composition, in order to forecast virosis, i.e. potential plant and tuber infection periods. Monitoring the aphid vectors of potato viruses enables determination of optimum dates for haulm destruction when higher than normal numbers of winged aphids as vectors of economically harmful diseases have been observed. Haulm destruction in a potato crop reduces the risk of plant infection and virus translocation from the aboveground parts to tubers, thus keeping the proportion of infected tubers within tolerance limits allowed for certain categories of seed potatoes. This practice has positive effects if used in combination with other viral disease control measures; otherwise, it becomes ineffective. This paper provides an integral analysis of the effects and role of monitoring outbreaks of aphids, their abundance and species composition in timing haulm growth termination to prevent plant infection, virus translocation and tuber infestation in potato crops in Serbia and the wider region.

  19. Effect of pre-sowing magnetic field treatment to garden pea (pisum sativum l.) seed on germination and seedling growth

    International Nuclear Information System (INIS)

    The seeds of garden pea ( Pisum sativum L. cv. climax) were exposed to full-wave rectified sumusoidal non-uniform magnetic fields of strength 60 mT, 120 mT and 180 mT for 5, 10 and 15 min prior to sowing. The magnetically treated seeds were sown according to the protocol of International Seed Testing Association (ISTA). Magnetically treated seed showed significant increase in germination. The emergence index, final emergence index and vigor index increased by 86.43%, 13.21% and 204.60%, respectively. It was found that exposure of 5 min for magnetic field strengths of 60 mT and 180 mT significantly enhanced the germination parameters of the pea and these treatments can be used practically to accelerate the germination in garden pea. (author)

  20. The influence of rate and time of nitrate supply on nitrogen fixation and yield in pea (Pisum sativum L.)

    DEFF Research Database (Denmark)

    Jensen, Erik Steen

    1986-01-01

    pea, by the lowest rate of nitrate at this application time. The pea very efficiently took up and assimilated the nitrate N supplied. The average fertilizer N recovery was 82%. The later the N was supplied the more efficiently it was recovered. When nitrate was supplied at the flat pod growth stage 88......The influence of nitrate N supply on dry matter production, N content and symbiotic nitrogen fixation in soil-grown pea (Pisum sativum L.) was studied in a pot experiment by means of15N fertilizer dilution. In pea receiving no fertilizer N symbiotic nitrogen fixation, soil and seed-borne N...... contributed with 82, 13 and 5% of total plant N, respectively. The supply of low rates of nitrate fertilizer at sowing (“starter N”) increased the vegetative dry matter production, but not the seed yield significantly. Nitrogen fixation was not significantly decreased by the lower rates of nitrate but higher...

  1. The same allele of translation initiation factor 4E mediates resistance against two potyvirus species in Pisum sativum

    DEFF Research Database (Denmark)

    Bruun-Rasmussen, Marianne; Møller, I S; Tulinius, G;

    2007-01-01

    was overcome, and virus from these plants had a codon change causing an Arg to His change at position 116 of the predicted viral genome-linked protein (VPg). Accordingly, plants carrying the wlv resistance gene were infected upon inoculation with BYMV-W derived from cDNA with a His codon at position 116......Pathogenicity of two sequenced isolates of Bean yellow mosaic virus (BYMV) was established on genotypes of Pisum sativum L. reported to carry resistance genes to BYMV and other potyviruses. Resistance to the white lupin strain of BYMV (BYMV-W) is inherited as a recessive gene named wlv that maps...... to linkage group VI together with other Potyvirus resistances. One of these, sbm1, confers resistance to strains of Pea seedborne mosaic virus and previously has been identified as a mutant allele of the eukaryotic translation initiation factor 4E gene (eIF4E). Sequence comparison of eIF4E from BYMV...

  2. Differential changes in size distribution of xyloglucan in the cell walls of gravitropically responding Pisum sativum epicotyls

    Science.gov (United States)

    Talbott, L. D.; Pickard, B. G.

    1994-01-01

    Growth-related change in the size distribution of hemicellulosic wall polymers during the gravitropic curvature response of intact pea (Pisum sativum L. cv Alaska) epicotyls was examined by gel-filtration chromatography. The gravitropic response was characterized by the appearance of curvature 20 to 30 min after horizontal placement, with 35 degrees of curvature attained by 80 min. Correlated with the onset of curvature, on the upper side of the epicotyl, there was a conspicuous transient increase in the abundance of relatively large hemicellulosic xyloglucan polymers, similar to increases previously found under conditions where diminished wall extensibility was expected. On the lower side there was a moderate, slower, and longer-term increase in abundance of small xyloglucan, similar to changes previously found in connection with auxin-stimulated growth responses. Both shifts occurred primarily in the epidermis. They appear to represent two coordinated physiological mechanisms contributing to differential growth.

  3. Callose deposition during gravitropism of Zea mays and Pisum sativum and its inhibition by 2-deoxy-D-glucose

    Science.gov (United States)

    Jaffe, M. J.; Leopold, A. C.

    1984-01-01

    In etiolated corn (Zea mays L.) and etiolated pea (Pisum sativum L.) seedlings, a gravitropic stimulation induces the deposition of callose. In the corn coleoptiles this occurs within 5 min of gravity stimulation, and prior to the beginning of curvature. Both gravitropic curvature and callose deposition reach their maxima by 12 h. Within the first 2 h more callose is deposited on the upper (concave) side, but after 2-3 h, this deposition pattern is reversed. An inhibitor of protein glycosylation, 2-deoxy-D-glucose (DDG), inhibits callose production and considerably retards gravitropic bending in both species of plants. Mannose can relieve the inhibition of gravitropic bending by DDG. The pea mutant "Ageotropum", which does not respond to gravity when etiolated, also fails to produce callose in response to a gravitic stimulus. These correlations indicate that callose deposition may be a biochemical component of gravitropism in plant shoots.

  4. Cloning of Partial Sodium Channel Gene From Strains of Fenvalerate-Resistant and Susceptible Cotton Aphid(Aphis gossypii Glover)

    Institute of Scientific and Technical Information of China (English)

    SUN Lu-juan; GAO Xi-wu; ZHENG Bing-zong

    2003-01-01

    The strain of fenvalerate-resistant cotton aphids was selected using fenvalerate insecticide in the laboratory, the resistance factor of the strain was 199.54. Three degenerate primers were designed and used to perform PCR amplification. A cDNA encoding partial sodium channel gene was cloned from the fenvalerate-resistant and -susceptible strains. There were two nucleotide acid differences between fenvalerate-resistant strain and -susceptible strain, resulting in an amino acid mutation, Met→Leu. It is predicted that the mutation is related to the cotton aphid resistance to fenvalerate.

  5. Expression of an (E)-β-farnesene synthase gene from Asian peppermint in tobacco affected aphid infestation

    OpenAIRE

    Xiudao Yu; Yongjun Zhang; Youzhi Ma; Zhaoshi Xu; Genping Wang; Lanqin Xia

    2013-01-01

    Aphids are major agricultural pests that cause significant yield losses in crop plants each year. (E)-β-farnesene (EβF) is the main or only component of an alarm pheromone involved in chemical communication within aphid species and particularly in the avoidance of predation. EβF also occurs in the essential oil of some plant species, and is catalyzed by EβF synthase. By using oligonucleotide primers designed from the known sequence of an EβF synthase gene from black peppermint (Mentha × piper...

  6. The conformational stability and biophysical properties of the eukaryotic thioredoxins of Pisum sativum are not family-conserved.

    Directory of Open Access Journals (Sweden)

    David Aguado-Llera

    Full Text Available Thioredoxins (TRXs are ubiquitous proteins involved in redox processes. About forty genes encode TRX or TRX-related proteins in plants, grouped in different families according to their subcellular localization. For instance, the h-type TRXs are located in cytoplasm or mitochondria, whereas f-type TRXs have a plastidial origin, although both types of proteins have an eukaryotic origin as opposed to other TRXs. Herein, we study the conformational and the biophysical features of TRXh1, TRXh2 and TRXf from Pisum sativum. The modelled structures of the three proteins show the well-known TRX fold. While sharing similar pH-denaturations features, the chemical and thermal stabilities are different, being PsTRXh1 (Pisum sativum thioredoxin h1 the most stable isoform; moreover, the three proteins follow a three-state denaturation model, during the chemical-denaturations. These differences in the thermal- and chemical-denaturations result from changes, in a broad sense, of the several ASAs (accessible surface areas of the proteins. Thus, although a strong relationship can be found between the primary amino acid sequence and the structure among TRXs, that between the residue sequence and the conformational stability and biophysical properties is not. We discuss how these differences in the biophysical properties of TRXs determine their unique functions in pea, and we show how residues involved in the biophysical features described (pH-titrations, dimerizations and chemical-denaturations belong to regions involved in interaction with other proteins. Our results suggest that the sequence demands of protein-protein function are relatively rigid, with different protein-binding pockets (some in common for each of the three proteins, but the demands of structure and conformational stability per se (as long as there is a maintained core, are less so.

  7. Effects of elevated CO2 and plant genotype on interactions among cotton, aphids and parasitoids

    Institute of Scientific and Technical Information of China (English)

    Yu-Cheng Sun; Li Feng; Feng Gao; Feng Ge

    2011-01-01

    Effects of CO2 level (ambient vs.elevated) on the interactions among three cotton (Gossypium hirsutum) genotypes,the cotton aphid (Aphis gossypii Glover),and its hymenoptera parasitoid (Lysiphlebiajaponica Ashrnead) were quantified.It was hypothesized that aphid-parasitoid interactions in crop systems may be altered by elevated CO2,and that the degree of change is influenced by plant genotype.The cotton genotypes had high (M9101),medium (HZ401) and low (ZMS 13) gossypol contents,and the response to elevated CO2 was genotype-specific.Elevated CO2 increased the ratio of total non-structural carbohydrates to nitrogen (TNC:N) in the high-gossypol genotype and the mediumgossypol genotype.For all three genotypes,elevated CO2 had no effect on concentrations of gossypol and condensed tannins.A.gossypii fitness declined when aphids were reared on the high-gossypol genotype versus the low-gossypol genotype under elevated CO2.Furthermore,elevated CO2 decreased the developmental time of L.japonica associated with the high-gossypol genotype and the low-gossypol genotype,but did not affect parasitism or emergence rates.Our study suggests that the abundance of A.gossypii on cotton will not be directly affected by increases in atmospheric CO2.We speculate that A.gossypii may diminish in pest status in elevated CO2 and high-gossypol genotype environments because of reduced fitness to the high-gossypol genotype and shorter developmental time of L.japonica.

  8. Testing semiochemicals from aphid, plant and conspecific:attraction of Harmonia axyridis

    Institute of Scientific and Technical Information of China (English)

    Pascal D.Leroy; Thomas Schillings; Julien Farmakidis; Stéphanie Heuskin; Georges Lognay; Francois J.Verheggen; Yves Brostaux; Eric Haubruge; Frédéric Francis

    2012-01-01

    Abstract Harmonia axyridis Pallas (Coleoptera:Coccinellidae) is an invasive specie affecting the dynamics and composition of several guilds.Nowadays,no biological control method is available to reduce the populations of this harmful coccinellid.Attractants and semiochemicals seem to be the best alternative but only few studies have tested the impact of semiochemicals on this Asian lady beetle.In this work,through windtunnel expcriments,semiochemicals from aphids (Z,E-nepetalactone,[E]-β-farnesene,α-pinene and β-pinene),from coccinellids ([-]-β-caryophyllene) and from the nettle Urtica dioica L.were evaluated as potential attractants.The nettle volatile compounds ([Z]-3-hexenol and [E]-2-hexenal) were extracted using a Clevenger Apparatus and identified by headspace gas chromatography-mass spectroscopy.In the wind-tunnel experiments,the main components of the aphid alarm pheromone as well as a component of the aphid sexual pheromone strongly attracted both sexes of the Asian lady beetle while (-)-β-caryophyllene only attracted few individuals and had no impact on the males.The nettle extract as well as the (Z)-3-hexenol oriented both males and females to the odor source.The (E)-2-hexenal was shown to have no effect on females even if this green leaf volatile attracted males.Because Z,E-nepetalactone was identified as the most efficient attractant in the wind-tunnel experiments,this volatile was also tested in a potato field where H.axyridis has been showed to respond to this semiochemical.This study highlighted that Z,E-nepetalactone orientated the Asian lady beetle H.axyridis under natural conditions,indicating that this volatile compound could certainly help for an efficient biological control approach against this invasive specie.

  9. Feeding of Whitefly on Tobacco Decreases Aphid Performance via Increased Salicylate Signaling.

    Directory of Open Access Journals (Sweden)

    Haipeng Zhao

    Full Text Available The feeding of Bemisia tabaci nymphs trigger the SA pathway in some plant species. A previous study showed that B. tabaci nymphs induced defense against aphids (Myzus persicae in tobacco. However, the mechanism underlying this defense response is not well understood.Here, the effect of activating the SA signaling pathway in tobacco plants through B. tabaci nymph infestation on subsequent M. persicae colonization is investigated. Performance assays showed that B. tabaci nymphs pre-infestation significantly reduced M. persicae survival and fecundity systemically in wild-type (WT but not salicylate-deficient (NahG plants compared with respective control. However, pre-infestation had no obvious local effects on subsequent M. persicae in either WT or NahG tobacco. SA quantification results indicated that the highest accumulation of SA was induced by B. tabaci nymphs in WT plants after 15 days of infestation. These levels were 8.45- and 6.14-fold higher in the local and systemic leaves, respectively, than in controls. Meanwhile, no significant changes of SA levels were detected in NahG plants. Further, biochemical analysis of defense enzymes polyphenol oxidase (PPO, peroxidase (POD, β-1,3-glucanase, and chitinase demonstrated that B. tabaci nymph infestation increased these enzymes' activity locally and systemically in WT plants, and there was more chitinase and β-1, 3-glucanase activity systemically than locally, which was opposite to the changing trends of PPO. However, B. tabaci nymph infestation caused no obvious increase in enzyme activity in any NahG plants except POD.In conclusion, these results underscore the important role that induction of the SA signaling pathway by B. tabaci nymphs plays in defeating aphids. It also indicates that the activity of β-1, 3-glucanase and chitinase may be positively correlated with resistance to aphids.

  10. Homeopathic Preparations to Control the Rosy Apple Aphid (Dysaphis plantaginea Pass.

    Directory of Open Access Journals (Sweden)

    Eric Wyss

    2010-01-01

    Full Text Available A laboratory model system with the rosy apple aphid (Dysaphis plantaginea Pass. on apple seedlings was developed to study the effects of homeopathic preparations on this apple pest. The assessment included the substance Lycopodium clavatum and a nosode of the rosy apple aphid. Each preparation was applied on the substrate surface as aqueous solution of granules (6c, 15c, or 30c. Controls were aqueous solutions of placebo granules or pure water. In eight independent, randomized, and blinded experiments under standardized conditions in growth chambers, the development of aphids on treated and untreated apple seedlings was observed over 17 days, each. Six experiments were determined to assess the effects of a strict therapeutic treatment; two experiments were designed to determine the effects of a combined preventative and therapeutic treatment. After application of the preparations, the number of juvenile offspring and the damage on apple seedlings were assessed after 7 and 17 days, respectively. In addition, after 17 days, the seedling weight was measured. In the final evaluation of the six strictly therapeutic trials after 17 days, the number of juvenile offspring was reduced after application of L. clavatum 15c (-17%, p = 0.002 and nosode 6c (-14%, p = 0.02 compared to the pure water control. No significant effects were observed for leaf damage or fresh weight for any application. In the two experiments with combined preventative and therapeutic treatment, no significant effects were observed in any measured parameter. Homeopathic remedies may be effective in plant-pest systems. The magnitude of observed effects seems to be larger than in models with healthy plants, which renders plant-pest systems promising candidates for homeopathic basic research. For successful application in agriculture, however, the effect is not yet sufficient. This calls for further optimization concerning homeopathic remedy selection, potency level, dosage, and

  11. Transgenerational shifts in reproduction hormesis in green peach aphid exposed to low concentrations of imidacloprid.

    Directory of Open Access Journals (Sweden)

    Murali-Mohan Ayyanath

    Full Text Available Hormesis is a biphasic phenomenon that in toxicology is characterized by low-dose stimulation and high-dose inhibition. It has been observed in a wide range of organisms in response to many chemical stressors, including insects exposed to pesticides, with potential repercussions for agriculture and pest management. To address questions related to the nature of the dose-response and potential consequences on biological fitness, we examined transgenerational hormesis in the green peach aphid, Myzus persicae, when exposed to sublethal concentrations of the insecticide imidacloprid. A hormetic response in the form of increased reproduction was consistently observed and a model previously developed to test for hormesis adequately fit some of our data. However, the nature of the dose-response differed within and across generations depending upon the duration and mode of exposure. Decreased reproduction in intermediate generations confirmed that fitness tradeoffs were a consequence of the hormetic response. However, recovery to levels of reproduction equal to that of controls in subsequent generations and significantly greater total reproduction after four generations suggested that biological fitness was increased by exposure to low concentrations of the insecticide, even when insects were continuously exposed to the stressor. This was especially evident in a greenhouse experiment where the instantaneous rate of population increase almost doubled and total aphid production more than quadrupled when aphids were exposed to potato plants systemically treated with low amounts of imidacloprid. Our results show that although fitness tradeoffs do occur with hormetic responses, this does not necessarily compromise overall biological fitness.

  12. A BRIEF REVIEW ON SAFFLOWER APHID, UROLEUCON COMPOSITAE (THEOBALD AND ITS MANAGEMENT

    Directory of Open Access Journals (Sweden)

    N Jemimah

    2013-12-01

    Full Text Available Safflower (Carthamus tinctorius L. is one of the important oilseed crops in the world. The crop has been traditionally grown for its flowers as a source of dye for colouring food and fabrics. Safflower oil has highest content of linoleic acid (75%. India with an area of 2.71 lakh ha, production of 1.71 lakh tonnes of seed and average productivity of 632 kg/ha is the leading producer of safflower in the world (DOR, 2011. A total of 101 pests are known to attack safflower at different stages of crop growth and development (Singh et al., 1996. Amongst the various pests, the aphid Uroleucon compositae Theobald, badly affects the crop growth and yield. Nymphs as well as adults suck the cell sap from the lower surface of the leaves and tender shoots and impair the vitality of the plants. Besides sucking the sap from the plants, the aphids also excrete honeydew which attracts a black sooty mould that adversely affects the photosynthesis. Seed and oil content losses due to this pest to an extent of 20 to 80 per cent have been reported from different parts of the country (Singh et al., 2000. Control of safflower aphid has been achieved by using different insecticides. Recently, the emphasis is being given on ecological basis of control based on suitable integrated pest management strategies. Seasonal incidence helps in planning need based application of insecticides as it clearly reveals the insect peak activity as well as insect free periods during crop growth. To achieve satisfactory suppression of this destructive pest, manipulating the sowing time, testing and evaluation of newer insecticides are necessary. The available literature related to the present study has been reviewed under the following heads.

  13. Secretome of fungus-infected aphids documents high pathogen activity and weak host response

    DEFF Research Database (Denmark)

    Grell, Morten Nedergaard; Jensen, Annette Bruun; Olsen, Peter B.;

    2011-01-01

    Discovery of novel secretome proteins contributes to the understanding of host-pathogen interactions. Here we report a rich diversity of secreted proteins from the interaction between grain aphids (host, insect order Hemiptera) and fungi of the order Entomophthorales (insect pathogens), made...... possible by screening a cDNA library constructed directly on field sampled material with an advanced method, unbiased of known sequences and/or functions. We show for the first time that fungi from the genera Pandora and Entomophthora are armed with a battery of hydrolytic enzymes for penetration...

  14. Alteration of intersubunit acid–base pair interactions at the quasi-threefold axis of symmetry of Cucumber mosaic virus disrupts aphid vector transmission

    Energy Technology Data Exchange (ETDEWEB)

    Bricault, Christine A. [Department of Plant Pathology and Plant-Microbe Biology, 334 Plant Science Building, Cornell University, Ithaca, NY 14850 (United States); Perry, Keith L., E-mail: KLP3@cornell.edu [Department of Plant Pathology and Plant-Microbe Biology, 334 Plant Science Building, Cornell University, Ithaca, NY 14850 (United States)

    2013-06-05

    In the atomic model of Cucumber mosaic virus (CMV), six amino acid residues form stabilizing salt bridges between subunits of the asymmetric unit at the quasi-threefold axis of symmetry. To evaluate the effects of these positions on virion stability and aphid vector transmissibility, six charged amino acid residues were individually mutated to alanine. All of the six engineered viruses were viable and exhibited near wild type levels of virion stability in the presence of urea. Aphid vector transmissibility was nearly or completely eliminated in the case of four of the mutants; two mutants demonstrated intermediate aphid transmissibility. For the majority of the engineered mutants, second-site mutations were observed following aphid transmission and/or mechanical passaging, and one restored transmission rates to that of the wild type. CMV capsids tolerate disruption of acid–base pairing interactions at the quasi-threefold axis of symmetry, but these interactions are essential for maintaining aphid vector transmissibility. - Highlights: ► Amino acids between structural subunits of Cucumber mosaic virus affect vector transmission. ► Mutant structural stability was retained, while aphid vector transmissibility was disrupted. ► Spontaneous, second-site mutations restored aphid vector transmissibility.

  15. Study on aphid species diversity in Wuan National Forest Park%武安国家森林公园蚜虫物种多样性研究

    Institute of Scientific and Technical Information of China (English)

    卜志国; 杨晋宇; 张蕾

    2012-01-01

    By using the specimen and literatures of aphid from Wuan National Forest Park, the authors studied the aphid species diversity, aphid fauna and host plants diversity of aphid in the park. The results showed that the known 47 species of aphid belong to 23 genera and 5 families, and aphid species mainly consist of palaearctic - oriental and widespread. The host plants of aphids include 29 families, and aphididae has the most host plants, while drepanosiphidae ranks the second.%根据对河北武安国家森林公园蚜虫的标本采集和文献查阅,对该森林公园蚜虫的物种多样性、区系成分和寄主植物多样性进行了分析研究.结果表明:该区已知蚜虫5科23属47种;武安地处古北区南端,与东洋区种类有较明显的交汇,故蚜虫区系以古北+东洋种和广布种为主;已知蚜虫的寄主植物29科,其中蚜科寄主植物最为丰富,斑蚜科次之.

  16. Elucidating the resistance response of irradiated banana cv. Lakatan to banana bunchy top virus (BBTV) infection transmitted by the banana aphid Pentalonia nigronervosa Coquerol

    International Nuclear Information System (INIS)

    Development of banana bunchy top virus (BBTV)-resistant banana variety Lakatan through gamma-irradiation had been successfully done as part of integrated management strategies against the disease. Ten irradiated Lakatan lines exhibited resistance to BBTV. Resistance of these lines was evaluated based on symptomatology and host-virus relationship. Insect colony development on Lakatan banana irradiated lines was monitored by artificially inoculating viruliferous banana aphids, Pentalonia nigronervosa, and counting the resulting number of aphids per plant at weekly intervals. Resistance to virus multiplication of Lakatan irradiated lines was characterized by quantifying the virus titer through Enzyme-Linked Immunosorbent Assay (ELISA). Results showed that not all lines were suitable as hosts in establishing aphid population. The reaction of the mutant lines to the vector and the pathogen varied to some extent. Disease incidence in some cases was correlated with aphid preference. Disease incidence was significantly higher (50%) on lines that were preferred by aphids and lower (50%) in those that were not colonized. Some mutant lines with very low aphid colony count, however showed high BBTV incidence. Variability in the results could be affected by other factors such as the developmental stage of the plant and prevailing environmental conditions during the conduct of the experiment. Virus titer was also reduced on these mutant lines, thus reduced virus multiplication. Non-irradiated (control) Lakatan banana had comparably high population of aphids, high disease incidence, and high virus titer

  17. Influence of Plant Diversity on the Numerical Response of Eriopis connexa (Coleoptera: Coccinellidae to Changes in Cereal Aphid Density in Wheat Crops

    Directory of Open Access Journals (Sweden)

    María C. Tulli

    2013-01-01

    Full Text Available Cereal aphids cause economic injury to wheat crops. In Argentina, Eriopis connexa is an indigenous ladybird. In the present study, the numerical response of E. connexa to changes in aphid density on wheat crops with high and low plant diversity was investigated. The study was carried out in Balcarce, Buenos Aires, Argentina, from September to December 2007 and 2008, on two wheat crops with either a higher plant diversity (HPD with refuge strips or a lower plant diversity (LPD without refuge strips. Crops were sampled every week and the abundance of aphids and E. connexa was recorded. The dominant aphid species were Schizaphis graminum, Metopolophium dirhodum, and Sitobion avenae. Eriopis connexa showed a linear increase in the numerical response to an increase in aphid density, which varied in space and time. The abundance of E. connexa increased in relation to the crop development and aphid population and was higher in the HPD than in the LPD system. This predator increased its reproductive numerical response only in 2008, with a significant liner response in the HPD system. This suggests that the potential of E. connexa as a predator of cereal aphids also increases directly in proportion to landscape vegetal diversity.

  18. Identification of Two Soybean Aphid Biotypes%两个大豆蚜虫生物型的初步划分

    Institute of Scientific and Technical Information of China (English)

    肖亮; 王彪; 武天龙

    2013-01-01

    Soybean aphid (Aphis glycines Matsmura)is a major pest of soybean (Glycine max).The responses of seven soybean resources to two aphid isolates from Shanghai and Jilin were compared in this study.In choice and no-choice tests,P203,P746 and P574 showed resistance to both of the two aphids.No significant differences in the average number of aphids were observed between Dowling,Jackson and P203,P746,P574 21 days after infected with Shanghai aphid.However,the average number of aphids on plants of the two genotypes were more than three hundred 21 days after infected with Jilin aphid.The results indicated that the biotype of Shanghai aphid was distinct from that of Jilin aphid.%大豆蚜虫(Aphis glycines Matsumura)是危害大豆(Glycine max)的主要害虫之一.本研究比较了7份大豆资源对我国吉林蚜虫和上海蚜虫的反应.在选择性试验和非选择性试验中,P203、P746、P574等资源对两地蚜虫表现抗性.两个试验中,Dowling和Jackson接种上海蚜虫21d后蚜虫平均数量与P203、P746、P574等无显著性差异;但是,接种吉林蚜虫21d后蚜虫平均数量均在300头以上,表现为感蚜虫.以上结果表明上海蚜虫和吉林蚜虫属于不同的生物型.

  19. Leaf surface factors of transgenic Bt cotton associated with the feeding behaviors of cotton aphids: A case study on non-target effects

    Institute of Scientific and Technical Information of China (English)

    XUE Kun; DENG Su; WANG RongJiang; YAN FengMing; XU ChongRen

    2008-01-01

    The present paper reports case study results of the risk assessment of transgenic Bt cotton on a non-target pest, cotton aphid, Aphis gossypii. Several types of techniques, i.e., electrical penetration graph (EPG), light and electron microscopy, bioessays and chemical analysis, were applied to investigate physical and chemical leaf factors of 2 transgenic Bt cotton lines(GK12 and GK19) and their parental non-Bt cotton line (Simian3) associated with searching and feeding behaviors of cotton aphids on leaves or leaf extracts of cotton plants. EPG results showed that there were some differences among behaviors of cotton aphids on 2 Bt cotton and 1 non-Bt cotton lines. Cotton aphids performed similarly to leaf surface extracts from 3 cotton lines; and leaf surface chemicals, mainly volatiles and waxes,were almost identical in the components and concentrations among the cotton lines. However, three cotton lines were quite different from each other in the densities of certain kinds of covering trichomes.Therefore, the relationships between the physical characteristics and the searching behaviors of cotton aphids on the three cotton lines were constructed as the regression equations. Glandular trichomes and covering trichomes with 5 branches Influenced the cotton aphids' searching behaviors effectively;and other trichomes with other branches affected aphids in varying ways. These results demonstrated that leaf surface physical factors of transgenic Bt cotton lines different from their parental non-Bt line could affect the penetration behaviors of non-target cotton aphids. Cotton aphids penetrate and feed more easily on two Bt cotton lines than on the non-Bt cotton line.

  20. Leaf surface factors of transgenic Bt cotton associated with the feeding behaviors of cotton aphids: a case study on non-target effects.

    Science.gov (United States)

    Xue, Kun; Deng, Su; Wang, RongJiang; Yan, FengMing; Xu, ChongRen

    2008-02-01

    The present paper reports case study results of the risk assessment of transgenic Bt cotton on a non-target pest, cotton aphid, Aphis gossypii. Several types of techniques, i.e., electrical penetration graph (EPG), light and electron microscopy, bioassays and chemical analysis, were applied to investigate physical and chemical leaf factors of 2 transgenic Bt cotton lines (GK12 and GK19) and their parental non-Bt cotton line (Simian3) associated with searching and feeding behaviors of cotton aphids on leaves or leaf extracts of cotton plants. EPG results showed that there were some differences among behaviors of cotton aphids on 2 Bt cotton and 1 non-Bt cotton lines. Cotton aphids performed similarly to leaf surface extracts from 3 cotton lines; and leaf surface chemicals, mainly volatiles and waxes, were almost identical in the components and concentrations among the cotton lines. However, three cotton lines were quite different from each other in the densities of certain kinds of covering trichomes. Therefore, the relationships between the physical characteristics and the searching behaviors of cotton aphids on the three cotton lines were constructed as the regression equations. Glandular trichomes and covering trichomes with 5 branches influenced the cotton aphids' searching behaviors effectively; and other trichomes with other branches affected aphids in varying ways. These results demonstrated that leaf surface physical factors of transgenic Bt cotton lines different from their parental non-Bt line could affect the penetration behaviors of non-target cotton aphids. Cotton aphids penetrate and feed more easily on two Bt cotton lines than on the non-Bt cotton line.