Linoleic acid biosynthesis in the pea aphid,Acyrthosiphon pisum (Harris)

AbstractTrehalose serves multifarious roles in growth and development of insects. In this study, we demonstrated that the high trehalose diet increased the glucose content, and high glucose diet increased the glucose content but decreased the trehalose content of Acyrthosiphon pisum. RNA interference (RNAi) of trehalose-6-phosphate synthase gene (ApTPS) decreased while RNAi of trehalase gene (ApTRE) increased the trehalose and glucose contents. In the electrical penetration graph experiment, RNAi of ApTPS increased the percentage of E2 waveform and decreased the percentage of F and G waveforms. The high trehalose and glucose diets increased the percentage of E2 waveform of A. pisum red biotype. The correlation between feeding behavior and sugar contents indicated that the percentage of E1 and E2 waveforms were increased but np, C, F and G waveforms were decreased in low trehalose and glucose contents. The percentage of np, E1 and E2 waveforms were reduced but C, F and G waveforms were elevated in high trehalose and glucose contents. The results suggest that the A. pisum with high trehalose and glucose contents spent less feeding time during non-probing phase and phloem feeding phase, but had an increased feeding time during probing phase, stylet work phase and xylem feeding phase.

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Efficacy of Botanical Insecticides against the Pea Aphid, Acyrthosiphon pisum (Harris) and Effect on Some of Its Natural Enemies on Field Pea in South Central Ethiopia

Science Technology and Arts Research Journal ◽

10.4314/star.v4i2.7 ◽

2016 ◽

Vol 4 (2) ◽

pp. 53 ◽

Cited By ~ 1

Author(s):

Lemmessa Gemmeda ◽

Gashawbeza Ayalew

Keyword(s):

Natural Enemies ◽

Acyrthosiphon Pisum ◽

Field Pea ◽

Pea Aphid ◽

Botanical Insecticides ◽

Central Ethiopia ◽

South Central

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Cloning and functional analysis of the FAD2 gene family from desert shrub Artemisia sphaerocephala

BMC Plant Biology ◽

10.1186/s12870-019-2083-5 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 2

Author(s):

Xiumei Miao ◽

Lijing Zhang ◽

Xiaowei Hu ◽

Shuzhen Nan ◽

Xiaolong Chen ◽

...

Keyword(s):

Fatty Acid ◽

Linoleic Acid ◽

Gene Family ◽

Fatty Acid Biosynthesis ◽

Family Members ◽

Pcr Analysis ◽

Mrna Levels ◽

Acid Biosynthesis ◽

Desert Shrub ◽

Artemisia Sphaerocephala

Abstract Background Linoleic acid is an important polyunsaturated fatty acid, required for all eukaryotes. Microsomal delta-12 (Δ12) oleate desaturase (FAD2) is a key enzyme for linoleic acid biosynthesis. Desert shrub Artemisia sphaerocephala is rich in linoleic acid, it has a large FAD2 gene family with twenty-six members. The aim of this work is to unveil the difference and potentially functionality of AsFAD2 family members. Results Full-length cDNAs of twenty-one AsFAD2 genes were obtained from A. sphaerocephala. The putative polypeptides encoded by AsFAD2 family genes showed a high level of sequence similarity and were relatively conserved during evolution. The motif composition was also relatively conservative. Quantitative real-time PCR analysis revealed that the AsFAD2–1 gene was strongly expressed in developing seeds, which may be closely associated with the high accumulating ability of linoleic acid in A. sphaerocephala seeds. Although different AsFAD2 family members showed diverse response to salt stress, the overall mRNA levels of the AsFAD2 family genes was stable. Transient expression of AsFAD2 genes in the Nicotiana benthamiana leaves revealed that the encoded proteins were all located in the endoplasmic reticulum. Heterologous expression in Saccharomyces cerevisiae suggested that only three AsFAD2 enzymes, AsFAD2–1, − 10, and − 23, were Δ12 oleate desaturases, which could convert oleic acid to linoleic acid, whereas AsFAD2–1 and AsFAD2–10 could also produce palmitolinoleic acid. Conclusions This research reported the cloning, expression studies, subcellular localization and functional identification of the large AsFAD2 gene family. These results should be helpful in understanding fatty acid biosynthesis in A. sphaerocephala, and has the potential to be applied in the study of plant fatty acids traits.

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CORNICLE LENGTH AS A CRITERION FOR SEPARATING FIELD-COLLECTED NYMPHAL INSTARS OF THE PEA APHID, ACYRTHOSIPHON PISUM (HOMOPTERA: APHIDIDAE)

The Canadian Entomologist ◽

10.4039/ent1151615-12 ◽

1983 ◽

Vol 115 (12) ◽

pp. 1615-1619 ◽

Cited By ~ 7

Author(s):

William D. Hutchison ◽

David B. Hogg

Keyword(s):

Acyrthosiphon Pisum ◽

Pea Aphid ◽

Field Sample ◽

Rearing Temperature ◽

Multimodal Analysis

AbstractCornicle length measuremetns of Acyrthosiphon pisum (Harris) nymphs reared in the laboratory were instar-specific and unaffected by rearing temperature. A multimodal analysis of cornicle lengths of field-collected aphids clearly detected four distribution peaks (i.e., instars) in five different field populations, and there was generaaly little overlap between successive instar distributions. However, third and fourth instars in the spring field sample could not be separated accurately due to the shorter cornicle length of nymphs that developed from overwintered eggs. Cornicle length proved to be a useful criterion for separating virginoparous A. pisum instars in samples collected in southern Wisconsin.

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The Phytopathogen Dickeya dadantii (Erwinia chrysanthemi 3937) Is a Pathogen of the Pea Aphid

Applied and Environmental Microbiology ◽

10.1128/aem.72.3.1956-1965.2006 ◽

2006 ◽

Vol 72 (3) ◽

pp. 1956-1965 ◽

Cited By ~ 70

Author(s):

Anne-Marie Grenier ◽

Gabrielle Duport ◽

Sylvie Pagès ◽

Guy Condemine ◽

Yvan Rahbé

Keyword(s):

Acyrthosiphon Pisum ◽

Ecological Impact ◽

Sitophilus Oryzae ◽

Pea Aphid ◽

Erwinia Chrysanthemi ◽

Future Research ◽

Close Relative ◽

Bacterial Cells ◽

Dickeya Dadantii ◽

Phytopathogenic Bacterium

ABSTRACT Dickeya dadantii (Erwinia chrysanthemi) is a phytopathogenic bacterium causing soft rot diseases on many crops. The sequencing of its genome identified four genes encoding homologues of the Cyt family of insecticidal toxins from Bacillus thuringiensis, which are not present in the close relative Pectobacterium carotovorum subsp. atrosepticum. The pathogenicity of D. dadantii was tested on the pea aphid Acyrthosiphon pisum, and the bacterium was shown to be highly virulent for this insect, either by septic injury or by oral infection. The lethal inoculum dose was calculated to be as low as 10 ingested bacterial cells. A D. dadantii mutant with the four cytotoxin genes deleted showed a reduced per os virulence for A. pisum, highlighting the potential role of at least one of these genes in pathogenicity. Since only one bacterial pathogen of aphids has been previously described (Erwinia aphidicola), other species from the same bacterial group were tested. The pathogenic trait for aphids was shown to be widespread, albeit variable, within the phytopathogens, with no link to phylogenetic positioning in the Enterobacteriaceae. Previously characterized gut symbionts from thrips (Erwinia/Pantoea group) were also highly pathogenic to the aphid, whereas the potent entomopathogen Photorhabdus luminescens was not. D. dadantii is not a generalist insect pathogen, since it has low pathogenicity for three other insect species (Drosophila melanogaster, Sitophilus oryzae, and Spodoptera littoralis). D. dadantii was one of the most virulent aphid pathogens in our screening, and it was active on most aphid instars, except for the first one, probably due to anatomical filtering. The observed difference in virulence toward apterous and winged aphids may have an ecological impact, and this deserves specific attention in future research.

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