Статті в журналах: "EPG graph"

1

Dos Santos Marinho, Luis Fernando, Kedson Alves Silva, and Tanilson Dias dos Santos. "B2-EPG Split." Academic Journal on Computing, Engineering and Applied Mathematics 4, no. 1 (December 10, 2022): 1–7. http://dx.doi.org/10.20873/uft.2675-3588.2023.v4n1.p1-7.

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On this research we study EPG graphs, in particular, we are interested on investigate the intersection between split and B2-EPGgraph classes. The results found in the literature regarding split graphs only concern about characterization in B1-EPG, that despite bringing some graphs that belong to this class, the bend number of split graphs it is still unknown. We study the split graphs whose degree of vertices on independent set is less than 2. In this work we manipulate bipartite graphs and we present representation for some bipartite graphs in B2-EPG. We build an algorithm that create a Split B2-EPG representation, also we present another algorithm that builds a representation on a grid Qw×2y+1 for any Split graph, and other results.

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2

Sandanayaka, W. R. M., and N. E. M. Page-Weir. "Evaluation of host testing by comparing ingestion and settling behaviours." New Zealand Plant Protection 62 (August 1, 2009): 191–96. http://dx.doi.org/10.30843/nzpp.2009.62.4777.

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The electrical penetration graph (EPG) technique is being developed for rapid assessment of host range of potential xylem feeding invaders in New Zealand Stylet penetration behaviours of adult spittle bug Carystoterpa fingens were monitored for 12 h on grape lemon apple and kiwifruit plants using EPG A multiplechoice test of all four plant species was conducted concurrently with the EPG tests for comparison In EPG tests the longest probing and ingestion periods were recorded on grape and lemon while the shortest probing and ingestion periods were recorded on apple Results for kiwifruit were intermediate and not significantly different from the other plant types In the multiplechoice tests more insects were found on grape and lemon than on apple and kiwifruit The similar ranking of the host plants in both multiplechoice and EPG tests suggests that EPG is a valid tool for rapidly assessing host feeding acceptance and preference

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3

Giordanengo, Philippe. "EPG-Calc: a PHP-based script to calculate electrical penetration graph (EPG) parameters." Arthropod-Plant Interactions 8, no. 2 (February 26, 2014): 163–69. http://dx.doi.org/10.1007/s11829-014-9298-z.

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4

Sandanayaka, M. R. M., J. G. Charles, and K. J. Froud. "Potential use of electrical penetration graph (EPG) technology for biosecurity incursion response decision making." New Zealand Plant Protection 70 (August 8, 2017): 1–15. http://dx.doi.org/10.30843/nzpp.2017.70.18.

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Sap-sucking insects pose a significant biosecurity risk as they can cause direct damage to plants and may also vector serious plant pathogens. However, there is a paucity of tools for rapidly estimating the host range of such insects during a biosecurity incursion. The Electrical Penetration Graph (EPG) technique has been developed over the past 50 years for analysing, quantifying, and comparing the feeding behaviours of both phloem and xylem sap-sucking insects. Electrically generated waveforms associated with insects’ probing and feeding behaviours may allow a rapid assessment of the potential host range of invading sap sucking insects. This paper reviews the development and use of EPG, assesses potential for host-range testing of recent incursions, analyses when and how the EPG tool could be applied for response, and identifies seven points where EPG could aid biosecurity incursion response decision making. Three recent biosecurity responses could have benefited from EPG.

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5

Wójcicka, Agnieszka. "Surface Waxes as a Plant Defense Barrier Towards Grain Aphid." Acta Biologica Cracoviensia s. Botanica 57, no. 1 (June 1, 2015): 95–103. http://dx.doi.org/10.1515/abcsb-2015-0012.

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AbstractThe electrical penetration graph (EPG) method was used to quantify the effect of surface waxes on probing behaviour of the grain aphidSitobion avenaeF. (Hemiptera: Aphididae). The experiments showed that wax removal significantly affected probing behaviour ofS. avenae. Generally, the aphids feeding on the plants without wax had a shortened non-probing (EPG-pattern np) and prolonged penetration of peripheral tissues – epidermis and mesophyll (EPG-pattern C). The EPG tests also showed that the three tested extracts of surface waxes from waxy plants RAH 122 were active as aphicides against the grain aphid.

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6

Civolani, Stefano, Marilena Leis, Gilberto Grandi, Elisa Garzo, Edison Pasqualini, Stefano Musacchi, Milvia Chicca, Giuseppe Castaldelli, Remigio Rossi, and W. Freddy Tjallingii. "Stylet penetration of Cacopsylla pyri; an electrical penetration graph (EPG) study." Journal of Insect Physiology 57, no. 10 (October 2011): 1407–19. http://dx.doi.org/10.1016/j.jinsphys.2011.07.008.

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7

Rahman, Wahab A., and G. H. Collins. "Seasonal variations in the populations of infective larvae on pasture and the numbers of nematode eggs in the faeces of farmed goats." Journal of Helminthology 64, no. 3 (September 1990): 263–70. http://dx.doi.org/10.1017/s0022149x00012256.

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ABSTRACTThe levels of nematode egg production in goats and the availability of infective larvae (L3) on pasture were investigated on a dairy unit in New South Wales, Australia. The output of eggs by adult goats was always above 300 epg. The profile of the graph of larval availability in herbage paralleled those for temperature and rainfall, suggesting that larval peaks occurred when the temperature and availability of moisture were optimal. The dominant genus was Trichostrongylus, followed by Haemonchus, then Ostertagia. A larger proportion of Haemonchus larvae in the cultures of faeces were collected during the summer months.

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8

Sandanayaka, M. R. M., M. Nielsen, V. A. Davis, and R. C. Butler. "Do spittlebugs feed on grape? Assessing transmission potential for Xylella fastidiosa." New Zealand Plant Protection 70 (August 8, 2017): 31–37. http://dx.doi.org/10.30843/nzpp.2017.70.23.

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The bacterium Xylella fastidiosa is a causal agent of Pierce’s disease in grapevines and is considered to be vectored by several xylem-feeding insects. Xylella fastidiosa and its primary insect vector Homalodisca vitripennis are not currently present in New Zealand, but considered a biosecurity threat to the wine industry. Should it be introduced, infection and dispersal of X. fastidiosa within New Zealand vineyards could occur through extant vectors, especially spittlebugs. Electrical Penetration Graph technology was used to compare the feeding behaviour of three spittlebug species (Philaenus spumarius, Carystoterpa fingens and Carystoterpa minor) on grape (Vitis vinifera Sauvignon blanc) and their original host plants. Results suggest that Philaenus spumarius feeds on grape more than the other two spittlebug species. As Philaenus spumarius has been reported as a vector of X. fastidiosa, their potential to transmit the bacterium into grapevines is discussed based on the real feeding times recorded by EPG.

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9

Min, Ji-Hyun, Heon Yoon, Hay-Ri Kwon, Yong-Man Yu, and Young-Nam Youn. "Feeding Behavior of the Green Peach Aphid, Myzus persicae, against Several Insecticides Using Electrical Penetration Graph Techniques." Korean Journal of Pesticide Science 21, no. 2 (June 30, 2017): 198–213. http://dx.doi.org/10.7585/kjps.2017.21.2.198.

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10

Wu, Bin, Elizabeth Chun, Runshi Xie, Gary W. Knox, Mengmeng Gu, and Hongmin Qin. "Real-Time Feeding Behavior Monitoring by Electrical Penetration Graph Rapidly Reveals Host Plant Susceptibility to Crapemyrtle Bark Scale (Hemiptera: Eriococcidae)." Insects 13, no. 6 (May 25, 2022): 495. http://dx.doi.org/10.3390/insects13060495.

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Host range confirmation of invasive hemipterans relies on the evaluation of plant susceptibility though greenhouse or field trials, which are inefficient and time-consuming. When the green industry faces the fast-spreading threat of invasive pests such as crapemyrtle bark scale (Acanthococcus lagerstroemiae), it is imperative to timely identify potential host plants and evaluate plant resistance/susceptibility to pest infestation. In this study, we developed an alternative technology to complement the conventional host confirmation methods. We used electrical penetration graph (EPG) based technology to monitor the A. lagerstroemiae stylet-tip position when it was probing in different plant tissues in real-time. The frequency and relative amplitude of insect EPG waveforms were extracted by an R programming-based software written to generate eleven EPG parameters for comparative analysis between plant species. The results demonstrated that the occurrences of phloem phase and xylem phase offered conclusive evidence for host plant evaluation. Furthermore, parameters including the percentage of insects capable of accessing phloem tissue, time duration spent on initiating phloem phase and ingesting phloem sap, provided insight into why host plant susceptibility differs among similar plant species. In summary, this study developed a novel real-time diagnostic tool for quick A. lagerstroemiae host confirmation, which laid the essential foundation for effective pest management.

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11

Sandanayaka, W. R. M., A. Chhagan, and P. Ramankutty. "Host plant testing of the spittle bug carystoterpa fingens by stylet penetration behaviour." New Zealand Plant Protection 60 (August 1, 2007): 78–84. http://dx.doi.org/10.30843/nzpp.2007.60.4613.

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Carystoterpa fingens (Walker) is an endemic xylem feeder It was chosen as a model insect for the glassy winged sharp shooter (Homalodisca coagulata (Say)) The electrical penetration graph (EPG) technique was used to measure realtime stylet penetration and feeding behaviour of 48 adult C fingens on four plant types hebe (Hebe pubescens) rengarenga lily (Arthropodium cirratum) wild iris (Dietes bicolor) and cabbage (Brassica oleracea) over 12 days EPG waveforms were recorded for 12 hours and the duration of the main penetration events (pathway ingestion and nonprobing phases) of the insects were analysed to compare host preferences There were no significant differences in the duration of ingestion indicating that all the plants were potential hosts for C fingens Insects on hebe showed the shortest nonprobing time suggesting that hebe was the most preferred host as expected from observations in the wild

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Kindt, F., N. N. Joosten, D. Peters, and W. F. Tjallingii. "Characterisation of the feeding behaviour of western flower thrips in terms of electrical penetration graph (EPG) waveforms." Journal of Insect Physiology 49, no. 3 (March 2003): 183–91. http://dx.doi.org/10.1016/s0022-1910(02)00255-x.

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13

Jhou, Yi-Syuan, Sushanthi Poovendhan, Li-Hsin Huang, and Chi-Wei Tsai. "Host Acceptance and Plant Resistance: A Comparative Behavioral Study of Myzus persicae and Acyrthosiphon pisum." Insects 12, no. 11 (October 28, 2021): 975. http://dx.doi.org/10.3390/insects12110975.

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Aphids are prominent phloem-feeding insect pests. Myzus persicae and Acyrthosiphon pisum are generalist and specialist species, respectively. In this study, these two aphid species were used to investigate host acceptance and plant resistance to aphid feeding. M.persicae survived and reproduced on rape (Brassica rapa), but few individuals (9%) survived on faba bean (Vicia faba). A.pisum survived and reproduced on faba bean, but no A.pisum survived on rape. The probing and feeding behavior of M. persicae and A. pisum on rape and faba bean was examined using an electrical penetration graph (EPG) technique. The results demonstrated the feeding preferences of these two aphid species. The EPG results suggest that the resistance of faba bean to M. persicae and that of rape to A. pisum are likely residing in the phloem and mesophyll tissues, respectively. Due to the distinct probing and feeding behaviors, specialist and generalist aphids would have different impacts on the epidemiology of plant viral diseases. The findings can be applied to the management of viral diseases transmitted by specialist or generalist aphids in crop production.

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Chen, Yu, Laurent Serteyn, Zhenying Wang, KangLai He, and Frederic Francis. "Reduction of Plant Suitability for Corn Leaf Aphid (Hemiptera: Aphididae) Under Elevated Carbon Dioxide Condition." Environmental Entomology 48, no. 4 (May 22, 2019): 935–44. http://dx.doi.org/10.1093/ee/nvz045.

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Abstract In the current context of global climate change, atmospheric carbon dioxide (CO2) concentrations are continuously rising with potential influence on plant–herbivore interactions. The effect of elevated CO2 (eCO2) on feeding behavior of corn leaf aphid, Rhopalosiphum maidis (Fitch) on barley seedlings Hordeum vulgare L. was tracked using electrical penetration graph (EPG). The nutrient content of host plant and the developmental indexes of aphids under eCO2 and ambient CO2 (aCO2) conditions were also investigated. Barley seedlings under eCO2 concentration had lower contents of crude protein and amino acids. EPG analysis showed the plants cultivated under eCO2 influenced the aphid feeding behavior, by prolonging the total pre-probation time of the aphids (wandering and locating the feeding site) and the ingestion of passive phloem sap. Moreover, fresh body weight, fecundity and intrinsic population growth rate of R. maidis was significantly decreased in eCO2 in contrast to aCO2 condition. Our findings suggested that changes in plant nutrition caused by eCO2, mediated via the herbivore host could affect insect feeding behavior and population dynamics.

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Dancewicz, Katarzyna, Beata Gabryś, Iwona Morkunas, and Sławomir Samardakiewicz. "Probing behavior of Adelges laricis Vallot (Hemiptera: Adelgidae) on Larix decidua Mill: Description and analysis of EPG waveforms." PLOS ONE 16, no. 5 (May 18, 2021): e0251663. http://dx.doi.org/10.1371/journal.pone.0251663.

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Adelgidae are a sister group of Aphididae and Phylloxeridae within Hemiptera, Aphidoidea and occur exclusively on Pinaceae. The piercing-sucking mouthparts of Adelgidae are similar to those of aphids and it is believed that adelgids ingest sap from both the non-vascular and vascular (phloem) tissues. The aim of the present study was to identify and characterize the adelgid stylet activities during their penetration in plant tissues. The probing behavior of Adelges laricis Vallot (Hemiptera: Adelgidae) on European larch Larix decidua Mill. and sucrose diets was monitored using the DC-EPG (Electrical Penetration Graph technique = electropenetrography). The EPG waveforms were described based on amplitude, frequency, voltage level, and electrical origin of the observed traces, and associated with putative behavioral activities based on analogy with aphid activities. Waveform frequency, duration, and sequence were analysed as well. A. laricis generated EPG signals at two clearly distinct voltage levels positive and negative, suggesting extracellular and intracellular stylet penetration, respectively. The adelgid EPG patterns were ascribed to four behavioral phases, which were non-probing, pathway, phloem, and xylem phases. Non-probing referred to the position of the stylets outside the plant tissues. Pathway phase was represented by three waveform patterns that visualized extracellular stylet penetration in non-vascular tissues without potential drops (AC1), with serial short (1.2–1.5 s) potential drops (AC2), and with ‘aphid-like’ (5–10 s) potential drops (AC3). Phloem phase comprised three waveform patterns at intracellular level, which in all probability represented phloem salivation (AE1), and phloem sap passive (AE2) and active ingestion (AE3). AE3 was a newly described waveform, previously unreported from Hemiptera. Waveform AG represented the ingestion of xylem sap. The comparative analysis demonstrated that the gymnosperm-associated adelgids show certain similarities in probing behavior typical of aphids and phylloxerids on angiosperm plants. The present work is the first detailed analysis of specific adelgid stylet activities on gymnosperms.

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Sandanayaka, W. R. M., N. E. M. Page-Weir, and A. Fereres. "Real time EPG recordings of tomatopotato psyllid (Bactericera cockerelli) feeding on tomato." New Zealand Plant Protection 64 (January 8, 2011): 294. http://dx.doi.org/10.30843/nzpp.2011.64.6007.

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The stylet penetration behaviour of tomatopotato psyllid (TPP; Bactericera cockerelli Hemiptera Psyllidae) a phloem feeder was monitored using an electrical penetration graph (EPGDC system) technique Fifteen adult psyllids were randomly selected from a colony and monitored for 8 h on tomato plants under laboratory conditions EPG waveforms generated during stylet penetration into the plant tissues were categorised based on amplitude frequency voltage level and electrical origin The main waveforms representing salivary sheath secretion and other stylet pathway activities (C) first contact with phloem (D) salivation in phloem sieve tubes (E1) and phloem sap ingestion (E2) were similar to the Asian citrus psyllid Diaphorina citri and this was confirmed by histological studies Phloem ingestion was seen from 12 out of 15 psyllids tested The time to first contact of phloem from the beginning of recording was 1163 h and the total duration of phloem ingestion recorded was from 1 min to 52 h within the 8 h recording period The information gathered on the feeding behaviour of TPP from this study will be applicable for future studies to understand the transmission of Candidatus Liberibacter solanacearum by TPP as well as other Liberibacter and TPP management studies

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Houston Joost, P., Elaine A. Backus, David Morgan, and Fengming Yan. "Correlation of stylet activities by the glassy-winged sharpshooter, Homalodisca coagulata (Say), with electrical penetration graph (EPG) waveforms." Journal of Insect Physiology 52, no. 3 (March 2006): 327–37. http://dx.doi.org/10.1016/j.jinsphys.2005.11.012.

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George, Justin, Ramdas Kanissery, El-Desouky Ammar, Itze Cabral, Larry T. Markle, Joseph M. Patt, and Lukasz L. Stelinski. "Feeding Behavior of Asian Citrus Psyllid [Diaphorina citri (Hemiptera: Liviidae)] Nymphs and Adults on Common Weeds Occurring in Cultivated Citrus Described Using Electrical Penetration Graph Recordings." Insects 11, no. 1 (January 10, 2020): 48. http://dx.doi.org/10.3390/insects11010048.

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Asian citrus psyllid, Diaphorina citri, transmits Candidatus Liberibacter asiaticus (CLas), the putative causal agent of Huanglongbing disease. Although they primarily feed on the phloem of Citrus and related plants, when grove or host conditions are unfavorable, D. citri may be able to use weed species as alternate food sources for survival. To explore this possibility, electrical penetration graph (EPG) recordings (18 h) were performed to investigate the feeding behavior of psyllid adults and nymphs on three common south Florida weeds (Bidens alba, Eupatorium capillifolium, and Ludwigia octovalvis). EPG recordings revealed that the proportion of time spent by D. citri feeding on xylem was similar on all tested weed species (19%–22%) and on the positive control (20%), the preferred host, Citrus macrophylla. Very little to no phloem feeding was observed on weed species by either nymphs or adults. Histological studies using epifluorescence microscopy showed that salivary sheaths were branched and extended into xylem of weed species, whereas they ended in phloem on citrus plants. No choice behavioral assays showed that adults can obtain some nutrition by feeding on weed species (xylem feeding) and they may be able to survive on them for short intervals, when host conditions are unfavorable.

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George, Justin, Ramdas Kanissery, Mahesh Bashyal, Blessy Tamayo, and Lukasz L. Stelinski. "Survival and Feeding Behavior of Diaphorina citri (Hemiptera: Liviidae) Adults on Common Cover Crops in Citrus." Agriculture 12, no. 12 (December 19, 2022): 2175. http://dx.doi.org/10.3390/agriculture12122175.

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Asian citrus psyllid, Diaphorina citri, transmits Candidatus Liberibacter asiaticus (CLas), the bacterial pathogen responsible for citrus greening disease. To explore the possibility that cover crops in citrus groves may serve as refuges for this pathogen vector during unfavorable host conditions, psyllid feeding was investigated on six common cover crop species and citrus using electrical penetration graph (EPG) recordings and behavioral bioassays. EPG recordings showed that the proportion of time spent by D. citri feeding on xylem was similar or higher on all tested cover crops (17%–32%) compared to the positive control (12%), the preferred host, Citrus macrophylla. Very little to no phloem feeding was observed on cover crops by the adults. In the choice assays, more D. citri adults settled on buckwheat (Fagopyrum esculentum) and cowpea (Vigna unguiculata) than on the host, C. macrophylla, 24 h after release. No-choice assays showed that the citrus cover crop species evaluated extend the survival of D. citri up to 8 d because of xylem feeding. Our results indicate that some cover crop species may be less suitable refuge sites for D. citri than others, but none served as breeding sites or supported more than 8 d of survival.

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Jiménez, Jaime, María Arias-Martín, Aránzazu Moreno, Elisa Garzo, and Alberto Fereres. "Barley yellow dwarf virus Can Be Inoculated During Brief Intracellular Punctures in Phloem Cells Before the Sieve Element Continuous Salivation Phase." Phytopathology® 110, no. 1 (January 2020): 85–93. http://dx.doi.org/10.1094/phyto-07-19-0260-fi.

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The distinguished intracellular stylet puncture called phloem-pd (potential drop [pd]) produced by Myzus persicae has been associated with the transmission of the semipersistently transmitted, phloem-limited Beet yellows virus (BYV, Closterovirus). However, the production of intracellular punctures in phloem cells (phloem-pd) by other aphid species and their role in the transmission of persistently transmitted, phloem-limited viruses are still unknown. Previous studies revealed that inoculation of the persistently transmitted, phloem-limited Barley yellow dwarf virus (BYDV, Luteovirus) is associated mainly with the sieve element continuous salivation phase (E1 waveform). However, the role of brief intracellular punctures that occur before the E1 phase in the inoculation of BYDV by aphids is unknown. We aimed to investigate whether the bird cherry-oat aphid Rhopalosiphum padi (Hemiptera: Aphididae) produced a stereotypical phloem-pd and to study its role in the inoculation of BYDV. The feeding behavior of viruliferous R. padi individuals in barley (Hordeum vulgare) was monitored via the electrical penetration graph (EPG) technique. The feeding process was artificially terminated after the observation of specific EPG waveforms: standard-pds, phloem-pd, and E1. Analysis of the EPG recordings revealed the production of a phloem-pd pattern by R. padi, in addition to a short, distinct E1-like pattern (short-E1), both resulting in successful inoculation of BYDV. Also, the transmission efficiency of BYDV was directly proportional to the time spent by aphids in intracellular salivation in phloem cells. Finally, we discussed the main differences between the inoculation process of semipersistent and persistently transmitted phloem-limited viruses by aphids.

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Hao, Zhou, Du Lingjun, Wan Fang-Hao, and Zhou Hongxu. "Comparative Analysis of Stylet Penetration Behaviors of Eriosoma lanigerum (Hemiptera: Aphididae) on Main Apple Cultivars in China." Journal of Economic Entomology 113, no. 4 (May 6, 2020): 1761–67. http://dx.doi.org/10.1093/jee/toaa085.

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Abstract The preference and behavioral mechanism of the feeding behavior of the woolly apple aphid, Eriosoma lanigerum (Hausmann), on Chinese apple cultivars was investigated using the electrical penetration graph (EPG) technique. Feeding of adult aphids was assessed for the four main cultivars of apple in China (Red Fuji, Ralls Genet, Starkrimson, and Jonagold) over an 8-h monitoring period, what that of fourth-instar nymphs was assessed for 8 h on Jonagold only. EPG waveforms representing the details of probing behaviors, parameters were measured for analysis. We found that at the nonphloem phase, the total duration of the nonpenetration (np) waveform and the total duration of the stylet pathway phase (the ‘C wave’) on Ralls Genet and Starkrimson were significantly longer than on Red Fuji. In addition, the phloem-feeding phase, the total duration of ‘release of saliva into the phloem’, (the E1 waveform) was significantly longer on Ralls Genet and Jonagold than on Red Fuji. The total duration of the ‘ingestion from sieve cells’ phase (the E2 waveform) on Red Fuji, meanwhile, was significantly longer than on Ralls Genet or Starkrimson. At the same time, when combined with EPG parameters, Red Fuji was found to have no obvious resistance to woolly apple aphid and to be a susceptible cultivar. This experiment also recorded the feeding waveform of fourth-instar aphid nymphs. Based on the phloem and nonphloem parameters recorded in this study, it was inferred that adult aphids are more likely than nymphs to feed on apple trees.

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Gebretsadik, Kifle Gebreegziabiher, Yong Zhang, and Julian Chen. "Screening and Evaluation for Antixenosis Resistance in Wheat Accessions and Varieties to Grain Aphid, Sitobion miscanthi (Takahashi) (Hemiptera: Aphididae)." Plants 11, no. 8 (April 18, 2022): 1094. http://dx.doi.org/10.3390/plants11081094.

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The grain aphid, Sitobion miscanthi causes serious damage by removing nutritional content from wheat plants and transmitting viral diseases. The use of resistant wheat cultivars is an effective method of aphid management. To identify S. miscanthi resistant cultivars, preliminary antixenosis resistance screening was conducted on 112 Ethiopian and 21 Chinese wheat accessions and varieties along with bioassay to test for further antixenosis resistance, identification of aphid feeding behavior using electrical penetration graph (EPG), and imaging of leaf trichome densities using a 3D microscope. According to antixenosis resistance screening, one highly-resistant, 25 moderately-resistant, and 38 slightly-resistant wheat cultivars to S. miscanthi were identified. Aphid choice tests showed that Luxuan266, 243726, and 213312 were the least preferred after 12, 24, 48, and 72 h of S. miscanthi release. Longer duration of Np, longer time to first probe, and shorter duration of E2 waveforms were recorded in Lunxuan266, 243726, and 213312 than in Beijing 837. The trichome density on adaxial and abaxial leaf surfaces of Lunxuan266, 243726 and 213312 was significantly higher than on those of Beijing 837. We concluded that Lunxuan266, 243726, and 213312 were antixenosis resistant to S. miscanthi based on the choice test, EPG results, and leaf trichome densities.

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Davis, J. A., and E. B. Radcliffe. "The Importance of an Invasive Aphid Species in Vectoring a Persistently Transmitted Potato Virus: Aphis glycines Is a Vector of Potato leafroll virus." Plant Disease 92, no. 11 (November 2008): 1515–23. http://dx.doi.org/10.1094/pdis-92-11-1515.

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Experiments were undertaken to determine soybean aphid (i) landing rates in potato fields, (ii) population dynamics on potato, (iii) feeding behavior compared with green peach aphid on potato using the electrical penetration graph technique (EPG), (iv) acquisition, retention, and transmission of Potato leafroll virus (PLRV), and (v) if soybean aphid–infested crop borders could increase PLRV spread in seed potato. Soybean aphid (Aphis glycines) landed on potato but failed to establish colonies. EPG showed no significant differences between the aphid species in preprobe, xylem phase, sieve element salivation, and phloem sap ingestion durations on potato. Soybean aphid acquired PLRV 78% of the time, and 75 and 70% of individual aphids retained infectivity after 72 and 144 h, respectively. Soybean aphid transmitted PLRV to susceptible potato with 6 to 9% efficiency. Prior to the invasion of this exotic pest, soybean borders were commonly used in Minnesota and North Dakota to protect seed potato against spread of Potato virus Y. In 2002 and 2004, PLRV incidence was not different in potatoes with soybean borders whether treated with insecticide or not. In 2005, with extreme soybean aphid pressure, potatoes with untreated (no insecticide) borders had significantly greater PLRV spread. This is the first report of soybean aphid transmitting PLRV.

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Nam, K. Jung, G. Powell, and J. Hardie. "Does phloem-based resistance to aphid feeding affect host-plant acceptance for reproduction? Parturition of the pea aphid, Acyrthosiphon pisum, on two near-isogenic lines of Medicago truncatula." Bulletin of Entomological Research 103, no. 6 (July 3, 2013): 683–89. http://dx.doi.org/10.1017/s0007485313000370.

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AbstractProbing behaviour (prior to parturition) and parturition of two clones (PS01 and N116) of the pea aphid, Acyrthosiphon pisum on two genotypes (near-isogenic lines (NILs)) (Q174_5.13 and Q174_9.10) of Medicago truncatula were investigated using electrical penetration graph (EPG) coupled with simultaneous visual monitoring for parturition. Line Q174_5.13 has been reported to show a phloem-based resistance to feeding in the clone PS01 but to be susceptible to the clone N116, whereas Q174_9.10 has shown to be susceptible to both aphid clones. The time taken to first parturition by clone PS01 was similar on Q174_5.13 and Q174_9.10. Prior to parturition, no aphids on Q174_5.13 contacted phloem, but 5% of the aphids on Q174_9.10 showed phloem salivation (recognized by EPG pattern E1). No phloem contact was observed with aphid clone N116 on either NILs of Medicago before first parturition occurred, and the time taken to first larviposition was similar on Q174_5.13 and Q174_9.10. The results indicate that the initiation of parturition of the clone PS01 and N116 on both NILs does not require the phloem contact and seems unchanged by a phloem-based resistance mechanism to feeding on Medicago. This finding suggests that host recognition and decisions about parturition occur before phloem contact or ingestion, and act independently on R-gene-mediated resistance.

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Mitchell, Paula Levin, S. Bernell Cooke, and Lisonéia F. Smaniotto. "Probing Behavior ofNezara viridulaon Soybean: Characterization and Comparison of Electrical Penetration Graph (EPG) Waveforms on Vegetative and Reproductive Plant Structures." Journal of Agricultural and Urban Entomology 34, no. 1 (January 2018): 19–43. http://dx.doi.org/10.3954/jaue18-09.1.

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Fan, Xiaofan, Yong Liu, Zhuo Zhang, Zhanhong Zhang, Jing Peng, Yang Gao, Limin Zheng, et al. "Bta06987, Encoding a Peptide of the AKH/RPCH Family: A Role of Energy Mobilization in Bemisia tabaci." Insects 13, no. 9 (September 13, 2022): 834. http://dx.doi.org/10.3390/insects13090834.

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Анотація:

A neuropeptide precursor encoded by Bta06987 associates with AKH neuropeptide. In the AKH/RPCH family, these members have been demonstrated to participate in energy mobilization in many insects. In our research, the Bta06987 gene from Bemisia tabaci was cloned, and the amino acid sequence analysis was performed. During the starvation of B. tabaci, the mRNA level of Bta06987 showed a significant elevation. We investigated the functions of Bta06987 in B. tabaci using RNA interference (RNAi), and the adult females of B. tabaci after being fed with dsBta06987 showed a higher glycogen and triglyceride levels and lower trehalose content than the control. Furthermore, in the electrical penetration graph (EPG) experiment, B. tabaci showed changes in feeding behavior after feeding with dsBta06987, such as the reduction in parameters of E waveform percentage and total feeding time. Our findings might be helpful in developing strategies to control pest and plant virus transmission.

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Kwon, Youngho, Nkulu Rolly Kabange, Ji-Yoon Lee, Bo Yoon Seo, Dongjin Shin, So-Myeong Lee, Jin-Kyung Cha, et al. "RNA-Seq and Electrical Penetration Graph Revealed the Role of Grh1-Mediated Activation of Defense Mechanisms towards Green Rice Leafhopper (Nephotettix cincticeps Uhler) Resistance in Rice (Oryza sativa L.)." International Journal of Molecular Sciences 22, no. 19 (October 2, 2021): 10696. http://dx.doi.org/10.3390/ijms221910696.

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The green rice leafhopper (GRH, Nephotettix cincticeps Uhler) is one of the most important insect pests causing serious damage to rice production and yield loss in East Asia. Prior to performing RNA-Seq analysis, we conducted an electrical penetration graph (EPG) test to investigate the feeding behavior of GRH on Ilpum (recurrent parent, GRH-susceptible cultivar), a near-isogenic line (NIL carrying Grh1) compared to the Grh1 donor parent (Shingwang). Then, we conducted a transcriptome-wide analysis of GRH-responsive genes in Ilpum and NIL, which was followed by the validation of RNA-Seq data by qPCR. On the one hand, EPG results showed differential feeding behaviors of GRH between Ilpum and NIL. The phloem-like feeding pattern was detected in Ilpum, whereas the EPG test indicated a xylem-like feeding habit of GRH on NIL. In addition, we observed a high death rate of GRH on NIL (92%) compared to Ilpum (28%) 72 h post infestation, attributed to GRH failure to suck the phloem sap of NIL. On the other hand, RNA-Seq data revealed that Ilpum and NIL GRH-treated plants generated 1,766,347 and 3,676,765 counts per million mapped (CPM) reads, respectively. The alignment of reads indicated that more than 75% of reads were mapped to the reference genome, and 8859 genes and 15,815,400 transcripts were obtained. Of this number, 3424 differentially expressed genes (DEGs, 1605 upregulated in Ilpum and downregulated in NIL; 1819 genes upregulated in NIL and downregulated in Ilpum) were identified. According to the quantile normalization of the fragments per kilobase of transcript per million mapped reads (FPKM) values, followed by the Student’s t-test (p < 0.05), we identified 3283 DEGs in Ilpum (1935 upregulated and 1348 downregulated) and 2599 DEGs in NIL (1621 upregulated and 978 downregulated) with at least a log2 (logarithm base 2) twofold change (Log2FC ≥2) in the expression level upon GRH infestation. Upregulated genes in NIL exceeded by 13.3% those recorded in Ilpum. The majority of genes associated with the metabolism of carbohydrates, amino acids, lipids, nucleotides, the activity of coenzymes, the action of phytohormones, protein modification, homeostasis, the transport of solutes, and the uptake of nutrients, among others, were abundantly upregulated in NIL (carrying Grh1). However, a high number of upregulated genes involved in photosynthesis, cellular respiration, secondary metabolism, redox homeostasis, protein biosynthesis, protein translocation, and external stimuli response related genes were found in Ilpum. Therefore, all data suggest that Grh1-mediated resistance against GRH in rice would involve a transcriptome-wide reprogramming, resulting in the activation of bZIP, MYB, NAC, bHLH, WRKY, and GRAS transcription factors, coupled with the induction of the pathogen-pattern triggered immunity (PTI), systemic acquired resistance (SAR), symbiotic signaling pathway, and the activation of genes associated with the response mechanisms against viruses. This comprehensive transcriptome profile of GRH-responsive genes gives new insights into the molecular response mechanisms underlying GRH (insect pest)–rice (plant) interaction.

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LEI, Hong, Joop C. VAN LENTEREN, and Ru M. XU. "Effects of plant tissue factors on the acceptance of four greenhouse vegetable host plants by the greenhouse whitefly: an Electrical Penetration Graph (EPG) study." European Journal of Entomology 98, no. 1 (March 15, 2001): 31–36. http://dx.doi.org/10.14411/eje.2001.005.

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Moreno, Aranzazu, W. Freddy Tjallingii, Gabriela Fernandez-Mata, and Alberto Fereres. "Differences in the mechanism of inoculation between a semi-persistent and a non-persistent aphid-transmitted plant virus." Journal of General Virology 93, no. 3 (March 1, 2012): 662–67. http://dx.doi.org/10.1099/vir.0.037887-0.

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Inoculation of the semi-persistent cauliflower mosaic virus (CaMV, genus Caulimovirus) is associated with successive brief (5–10 s) intracellular stylet punctures (pd) when aphids probe in epidermal and mesophyll cells. In contrast to non-persistent viruses, there is no evidence for which of the pd subphases (II-1, II-2 and II-3) is involved in the inoculation of CaMV. Experiments were conducted using the electrical penetration graph (EPG) technique to investigate which particular subphases of the pd are associated with the inoculation of CaMV to turnip by its aphid vector Brevicoryne brassicae. In addition, the same aphid species/test plant combination was used to compare the role of the pd subphases in the inoculation of the non-persistent turnip mosaic virus (TuMV, genus Potyvirus). Inoculation of TuMV was found to be related to subphase II-1, confirming earlier results, but CaMV inoculation appeared to be related exclusively to subphase II-2 instead. The mechanism of CaMV inoculation and the possible nature of subphase II-2 are discussed in the scope of our findings.

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Jin, Yan, Wendan Zhang, Yumei Dong, and Ai Xia. "Feeding Behavior of Riptortus pedestris (Fabricius) on Soybean: Electrical Penetration Graph Analysis and Histological Investigations." Insects 13, no. 6 (May 28, 2022): 511. http://dx.doi.org/10.3390/insects13060511.

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Riptortus pedestris (Fabricius) is a major agricultural pest feeding on soybean pods and seeds. The large populations occur during seed maturity stages from pod filling to harvest. Its infestation results in shriveled and dimpled seeds while vegetative structures (leaflet and stem) remain green, known as “Stay Green” syndrome. Additional evidence also demonstrates that soybean pods and seeds are required for Riptortus pedestris development. However, the feeding behavior strategies employed by this stink bug to feed on soybean plants are still not clear. In the present study, the feeding behaviors of R. pedestris on soybean plants were recorded by electropenetrography (EPG), and a waveform library was created for this species. A total of five phases of waveforms—nonprobing, pathway (Rp1), xylem sap ingestion (Rp2), salivation and ingestion (Rp3), and interruption (Rp4)—were identified. Non-probing waveforms Z and NP and pathway (Rp1) were found in all tested plant structures (leaflet, stem, cotyledon, and pods). Waveform Rp2 (xylem sap ingestion, xylem ingestion) was primarily recorded during R. pedestris feeding on leaflets and stems, while Rp3 (salivation/ingestion) was only observed during feeding on cotyledon and pods. Histological examinations confirmed that correlation between Rp2 and stylet tip positioning in the xylem vessel in leaflets and stems. Stylet tips end in the tissues of cotyledon and pods when Rp3 is recorded. Taken together, our results demonstrate that R. pedestris ingests xylem sap from vegetative tissues of soybean (leaflet and stem) via a salivary sheath strategy to obtain water. It mainly acquires nutrients from soybean pods and/or seeds using cell-rupture tactics. This study provided insightful information to understand the field occurrence patterns of “Stay Green” syndrome, which may have important implications for pest control.

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Hennig, Juergen, Matthias Weigel, and Klaus Scheffler. "Calculation of flip angles for echo trains with predefined amplitudes with the extended phase graph (EPG)-algorithm: Principles and applications to hyperecho and TRAPS sequences." Magnetic Resonance in Medicine 51, no. 1 (2003): 68–80. http://dx.doi.org/10.1002/mrm.10658.

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Paprocka, Marlena, Anna Gliszczyńska, Katarzyna Dancewicz, and Beata Gabryś. "Novel Hydroxy- and Epoxy-cis-Jasmone and Dihydrojasmone Derivatives Affect the Foraging Activity of the Peach Potato Aphid Myzus persicae (Sulzer) (Homoptera: Aphididae)." Molecules 23, no. 9 (September 15, 2018): 2362. http://dx.doi.org/10.3390/molecules23092362.

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Jasmonates show great potential in sustainable agriculture due to their various roles in natural mechanisms of plant defense, and because they are non-toxic, non-mutagenic, and easily metabolized. The aim of the study was to explore structure–activity relationships of dihydrojasmone, cis-jasmone, and their derivatives at the plant–aphid interface. We focused on the behavioral responses of aphids, following the exogenous application of natural jasmonates and their derivatives to the host plants. Aphid probing behavior was examined using an electrical penetration graph technique (EPG). The chemoenzymatic transformation of cis-jasmone and the activity of two new derivatives are described. The application of cis-jasmone, dihydrojasmone, the hydroxyderivatives, epoxyderivatives, and alkyl-substituted δ-lactones hindered the foraging activity of Myzus persicae (Sulz.) (Hemiptera: Aphididae) during early stages of probing at the level of non-phloem tissues. The application of saturated bicyclic epoxy-δ-lactone enhanced plant acceptance by M. persicae. Jasmonate derivatives containing a hydroxy group, especially in correlation with a lactone ring, were more active than natural compounds and other derivatives studied. Jasmonates of the present study are worth considering as elements of sustainable aphid control as components of the “push–pull” strategy.

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Xi, Chanyuan, Sheraz Ahmad, Julong Yu, Jieyu Zhang, Yu Chen, Guo Zhang, Haowen Zhu, Linquan Ge, Xiangyang Yu, and Zhaolin Shu. "Seed Coating with Triflumezopyrim Induces the Rice Plant’s Defense and Inhibits the Brown Planthopper’s Feeding Behavior." Agronomy 12, no. 5 (May 17, 2022): 1202. http://dx.doi.org/10.3390/agronomy12051202.

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Triflumezopyrim (TFM), a novel mesoionic insecticide, has been effective in controlling sucking insect pests such as the brown planthopper (BPH). However, the mechanism of TFM as a seed coating agent in paddy fields remains unclear. Here, we investigate the seed germination rates (>80%) and seedling emergence rates (>85%) of rice treated with TFM at 0, 22.5, 45.0, 67.5, and 90.0 g a.i. ha−1 with no significant effect on germination rates. In addition, the low TFM residue concentration (0.04 mg. kg−1) is maintained in the rice stem. Meanwhile, the TFM seeds’ treatments lead to increased oxalic acid, flavonoids, total phenol, callose contents, and elevated C/N ratio in rice plants at 60 and 90 days after sowing (DAS). The electrical penetration graph (EPG) results indicate that TFM as a seed coating treatment prolongs the non-probing period and inhibits phloem sap ingestion at 90 DAS. Furthermore, the mechanically transplanted rice treated with TFM provides long-term prevention against the BPH infestation. This study demonstrates that seeds treated with TFM play a vital role in controlling the BPH population up to >90%. These results provide a novel valuable control strategy for BPH in the rice fields.

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KRZYŻANOWSKI, ROBERT, IZABELA BEDNARCZYK, and JOLANTA CUDZIŁO-ABRAMCZUK. "Effect of chlorophenoxy herbicides residues on probing behavior of cereal aphid." Agronomy Science 73, no. 3 (November 29, 2018): 29–36. http://dx.doi.org/10.24326/asx.2018.3.3.

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Chlorophenoxyacetic herbicides such as 4-chloro-2-methylphenoxyacetic acid (MCPA) and 2,4-dichlorophenoxyacetic acid (2,4-D) are used for cereal protection. However, some of them penetrate the tissues of protected plants and also get in contact with cereal pathogens. The up-to-date studies concerned their effectiveness in combating the weeds without paying attention to the herbivores occurring in cereal agrocenoses. Therefore, the aim of the present study was to determine the effect of chlorophenoxyacetic herbicides on the probing behavior of grain aphid, Sitobion avenae (F.), bird cherry-oat aphid, Rhopalosiphum padi (L.) and rose-grain aphid, Metopolophium dirhodum (Walk.). The experiment was carried out on wingless females feeding on winter wheat seedlings of Tonacja cv. using the electronic penetration graph (EPG) method. Tested herbicide preparations exerted an influence on the probing behavior of all aphids examined. The inhibitory effect of MCPA and 2,4-D on the uptake of phloem juice was found. It has been shown that chlorophenoxyacetic herbicides are not only effective in combating the weeds of cereal crops, but can also have positive side-effects in the form of limiting the cereal aphids population.

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Stec, Katarzyna, Bożena Kordan, and Beata Gabryś. "Effect of Soy Leaf Flavonoids on Pea Aphid Probing Behavior." Insects 12, no. 8 (August 22, 2021): 756. http://dx.doi.org/10.3390/insects12080756.

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Flavonoids detected in soybean Glycine max (L.) Merr. (Fabaceae) cause various alterations in the metabolism, behavior, and development of insect herbivores. The pea aphid Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae) poses potential threat to soybeans, but the effect of individual flavonoids on its feeding-associated behavior is relatively unknown. We monitored probing behavior (stylet penetration activities) of A. pisum on its preferred host plant, Pisum sativum L. untreated (control) and treated with 0.1% ethanolic solutions of flavonoids apigenin, daidzein, genistein, and kaempferol. We applied the electrical penetration graph (electropenetrography, EPG) technique, which visualizes the movements of aphid stylets within plant tissues. None of the applied flavonoids affected the propensity to probe the plants by A. pisum. However, apigenin enhanced the duration of probes in non-phloem tissues, which caused an increase in the frequency and duration of stylet mechanics derailment and xylem sap ingestion but limited the ingestion of phloem sap. Daidzein caused a delay in reaching phloem vessels and limited sap ingestion. Kaempferol caused a reduction in the frequency and duration of the phloem phase. Genistein did not affect aphid probing behavior. Our findings provide information for selective breeding programs of resistant plant cultivars to A. pisum.

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Pompon, J., and Y. Pelletier. "Changes in aphid probing behaviour as a function of insect age and plant resistance level." Bulletin of Entomological Research 102, no. 5 (March 30, 2012): 550–57. http://dx.doi.org/10.1017/s0007485312000120.

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AbstractAphids perform a series of behaviours to assess feeding suitability and, hence, to select a plant. Little information, however, is available on such behaviour after aphids have settled on a plant. Observation of probing behaviour over an extended period of time can improve our understanding of insect-plant interactions and is instrumental in the study of crop resistance. Here, we assessed the influence of aphid age and plant resistance level on aphid behaviour. An electrical penetration graph (EPG) technique was implemented to monitor the behaviour of potato aphid, Macrosiphum euphorbiae, alates on potato, Solanum tuberosum, and on both a susceptible and a resistant genotype of a wild Solanum species, S. chomatophilum. The behaviour was measured at daily intervals for the first seven days following adult emergence. The results indicated independent and interacting effects of aphid age and plant genotype on probing behaviour. Some behavioural discrepancies between susceptible and resistant genotypes were only observed after the first day, thus highlighting the limits of punctual one-day behavioural studies to assess plant resistance mechanisms. Our work supports the hypothesis that aphids continuously adapt their behaviour to the plant characteristics.

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Wróblewska-Kurdyk, Anna, Katarzyna Dancewicz, Anna Gliszczyńska, and Beata Gabryś. "New insight into the behaviour modifying activity of two natural sesquiterpenoids farnesol and nerolidol towards Myzus persicae (Sulzer) (Homoptera: Aphididae)." Bulletin of Entomological Research 110, no. 2 (September 27, 2019): 249–58. http://dx.doi.org/10.1017/s0007485319000609.

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AbstractThe effect of structurally related sesquiterpenoids (E,E)-farnesol and cis-nerolidol on the host-plant selection behaviour of the peach potato aphid Myzus persicae (Sulz.) was evaluated using electrical penetration graph (EPG) technique. No repellent effects of (E,E)-farnesol and (Z)-nerolidol to M. persicae were found but aphid probing activities on (E,E)-farnesol- and cis-nerolidol-treated plants were restrained. During non-phloem phases of probing, neither (E,E)-farnesol nor (Z)-nerolidol affected the cell puncture activity. On (E,E)-farnesol-treated plants, the total duration of phloem phase, the mean duration of individual sustained ingestion periods were significantly lower, and the proportion of phloem salivation was higher than on control plants. On (Z)-nerolidol-treated plants, the occurrence of the first phloem phase was delayed, and the frequency of the phloem phase was lower than on control plants. The freely moving aphids were reluctant to remain on (E,E)-farnesol- and (Z)-nerolidol-treated leaves for at least 24 h after exposure. (E,E)-Farnesol and (Z)-nerolidol show complementary deterrent properties, (E,E)-farnesol showing ingestive and post-ingestive activities and nerolidol showing pre-ingestive, ingestive, and post-ingestive deterrent activities.

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Ashrafi-Payaman, Nosratali, Mohammad Reza Kangavari, and Amir Mohammad Fander. "A new method for graph stream summarization based on both the structure and concepts." Open Engineering 9, no. 1 (November 2, 2019): 500–511. http://dx.doi.org/10.1515/eng-2019-0060.

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AbstractGraph datasets are common in many application domains and for which their graphs are usually massive. One solution to process such massive graphs is summarization. There are two kinds of graphs, stationary and stream. For stationary graphs, a number of summarization algorithms are available while for graph stream there is no a comprehensive summarization method that summarizes a graph stream based on the structure, vertex attributes or both with varying contributions. This is because of challenges of graph stream, which are volume of data and changing of data over time. In this paper, we propose a method based on sliding-window model for which summarizes a graph stream based on a combination of the structure and vertex attributes. We proposed a new structure for summary graphs and also proposed new methods for comparing two summary graphs. To the best of our knowledge, this is the first method that summarizes a graph stream based on both the structure and vertex attributes with varying contributions. Through extensive experiments on real dataset of Amazon co-purchasing products, we have demonstrated the performance of the proposed method.

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Wróblewska-Kurdyk, Anna, Radosław Gniłka, Katarzyna Dancewicz, Aleksandra Grudniewska, Czesław Wawrzeńczyk та Beata Gabryś. "β-Thujone and Its Derivatives Modify the Probing Behavior of the Peach Potato Aphid". Molecules 24, № 10 (14 травня 2019): 1847. http://dx.doi.org/10.3390/molecules24101847.

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Thujone is a natural biologically active monoterpene ketone component of essential oils of numerous plants. The aim of the study was to evaluate the effect of β-thujone and β-thujone derivatives bisulfite adduct, lactone, oxime, and lactam application on behavior of Myzus persicae (Sulz.) (Hemiptera: Aphididae) during probing and settling. The choice and no-choice tests (aphid settling and Electrical Penetration Graph (EPG), respectively) revealed that stereochemistry of thujone was important for biological activity (β-thujone caused changes in aphid behavior while α-thujone did not) and that cyclopentane ring modifications and functional groups addition gave derivatives that possessed stronger and more durable deterrent effects. The most effective modification was the incorporation of a lactam moiety into the β-thujone molecule. Application of β-thujone lactam limited aphid settling for at least 24 h, caused restlessness in aphids and a delay or failure in reaching phloem phase by M. persicae. β-Thujone lactam can be considered a deterrent of medium potency with activity expressed at preingestive phase of aphid probing. Other compounds did not restrain aphid stylet penetration in non-phloem tissues but slightly limited sap ingestion (lactone, oxime), and restrained aphid settling for a period of less than 24 h (β-Thujone, bisulphite adduct, lactone).

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Sytykiewicz, Hubert, Iwona Łukasik, Sylwia Goławska, Iwona Sprawka, Artur Goławski, Julia Sławianowska, and Katarzyna Kmieć. "Expression of Thioredoxin/Thioredoxin Reductase System Genes in Aphid-Challenged Maize Seedlings." International Journal of Molecular Sciences 21, no. 17 (August 31, 2020): 6296. http://dx.doi.org/10.3390/ijms21176296.

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Thioredoxins (Trxs) and thioredoxin reductases (TrxRs) encompass a highly complex network involved in sustaining thiol-based redox homeostasis in plant tissues. The purpose of the study was to gain a new insight into transcriptional reprogramming of the several genes involved in functioning of Trx/TrxR system in maize (Zea mays L.) seedlings, exposed to the bird cherry-oat aphid (Rhopalosiphum padi L.) or the rose-grass aphid (Metopolophium dirhodum Walk.) infestation. The biotests were performed on two maize genotypes (susceptible Złota Karłowa and relatively resistant Waza). The application of real-time qRT-PCR technique allowed to identify a molecular mechanism triggered in more resistant maize plants, linked to upregulation of thioredoxins-encoding genes (Trx-f, Trx-h, Trx-m, Trx-x) and thioredoxin reductase genes (Ftr1, Trxr2). Significant enhancement of TrxR activity in aphid-infested Waza seedlings was also demonstrated. Furthermore, we used an electrical penetration graph (EPG) recordings of M. dirhodum stylet activities in seedlings of the two studied maize varieties. Duration of phloem phase (E1 and E2 models) of rose-grass aphids was about three times longer while feeding in Waza plants, compared to Złota Karłowa cv. The role of activation of Trx/TrxR system in maintaining redox balance and counteracting oxidative-induced damages of macromolecules in aphid-stressed maize plants is discussed.

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Dancewicz, Katarzyna, Antoni Szumny, Czesław Wawrzeńczyk, and Beata Gabryś. "Repellent and Antifeedant Activities of Citral-Derived Lactones against the Peach Potato Aphid." International Journal of Molecular Sciences 21, no. 21 (October 28, 2020): 8029. http://dx.doi.org/10.3390/ijms21218029.

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Citral is well known for its antimicrobial, antifungal, and insecticidal activities. Natural sesquiterpene α-methylenelactones also exhibit a broad spectrum of biological activities. The aim of the study was to explore the effect of structural changes to citral molecules on citral behavior-modifying activity towards Myzus persicae. Specifically, the effects of the introduction of a γ-lactone moiety and methylene groups in α and γ positions of the lactone ring were investigated. The lactones were obtained in five-step (saturated lactone and γ-methylenelactone) or six-step (α-methylenelactone and α,γ-dimethylenelactone) syntheses from citral. The synthetic procedures and physical and spectral data of the lactones are presented. The settling behavior of freely moving aphids in choice and no-choice situations was monitored. The probing behavior of tethered M. persicae using the Electrical Penetration Graph (EPG) technique was also analyzed. Citral appeared a strong repellent and pre-ingestive and ingestive probing deterrent to M. persicae. The incorporation of a lactone moiety caused the loss of the repellent activity. α-Methylenelactone inhibited aphid settling and probing activities at pre-ingestive and ingestive phases. The saturated γ-lactone and α,γ-dimethylenelactone were the settling post-ingestive deterrents to M. persicae, which did not affect aphid probing activity. γ-Methylenelactone did not affect aphid behavior.

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Stec, Katarzyna, Joanna Kozłowska, Anna Wróblewska-Kurdyk, Bożena Kordan, Mirosław Anioł, and Beata Gabryś. "Effect of Naringenin and Its Derivatives on the Probing Behavior of Myzus persicae (Sulz.)." Molecules 25, no. 14 (July 13, 2020): 3185. http://dx.doi.org/10.3390/molecules25143185.

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Substances that alter insect behavior have attracted a lot of attention as potential crop protection agents. Naringenin (5,7,4′-trihydroxyflavanone) is a naturally occurring bioactive flavanone. We evaluated the influence of naringenin on aphid activities during individual phases of probing and feeding and the effect of structural modifications of naringenin on its activity towards aphids. We monitored the probing behavior of Myzus persicae (Sulz.) (Hemiptera: Aphididae) using the Electrical Penetration Graph (EPG) technique. The chemical modifications were the substitution of hydrogen atoms with methyl, ethyl or pentyl groups and the replacement of the carbonyl group in naringenin and its derivatives with an oxime moiety. Depending on the substituents, the activity of naringenin-derived compounds varied in potency and mode of action. Naringenin was an attractant of moderate activity, which enhanced sap ingestion. The naringenin derivative with two methyl groups—7,4′-di-O-methylnaringenin—was a deterrent, which hindered aphid probing in non-phloem tissues. Naringenin oxime derivatives with methyl substituents—7,4′-di-O-methylnaringenin oxime, 7-O-methylnaringenin oxime, and 5,7,4′-tri-O-methylnaringenin oxime—and the derivative with a pentyl substituent—7-O-pentylnaringenin oxime—were strong attractants which stimulated aphid probing in non-phloem tissues and the ingestion of phloem sap.

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43

Stec, Katarzyna, Bożena Kordan, and Beata Gabryś. "Quercetin and Rutin as Modifiers of Aphid Probing Behavior." Molecules 26, no. 12 (June 13, 2021): 3622. http://dx.doi.org/10.3390/molecules26123622.

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Rutin and its aglycone quercetin occur in the fruits, leaves, seeds, and grains of many plant species and are involved in plant herbivore interactions. We studied the effect of the exogenous application of rutin and quercetin on the probing behavior (= stylet penetration activities in plant tissues) of Acyrthosiphon pisum on Pisum sativum, Myzus persicae on Brassica rapa ssp. pekinensis, and Rhopalosiphum padi on Avena sativa using the electrical penetration graph technique (EPG = electropenetrography). The reaction of aphids to quercetin and rutin and the potency of the effect depended on aphid species, the flavonol, and flavonol concentration. Quercetin promoted probing activities of A. pisum within non-phloem and phloem tissues, which was demonstrated in the longer duration of probes and a trend toward longer duration of sap ingestion, respectively. M. persicae reached phloem in a shorter time on quercetin-treated B. rapa than on the control. Rutin caused a delay in reaching sieve elements by A. pisum and deterred probing activities of M. persicae within non-phloem tissues. Probing of R. padi was not affected by quercetin or rutin. The potency of behavioral effects increased as the applied concentrations of flavonols increased. The prospects of using quercetin and rutin in plant protection are discussed.

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Liu, Jinping, Chen Wang, Nicolas Desneux, and Yanhui Lu. "Impact of Temperature on Survival Rate, Fecundity, and Feeding Behavior of Two Aphids, Aphis gossypii and Acyrthosiphon gossypii, When Reared on Cotton." Insects 12, no. 6 (June 21, 2021): 565. http://dx.doi.org/10.3390/insects12060565.

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Aphid performance is sensitive to temperature changes. Previous studies found that Acyrthosiphon gossypii (Mordviiko) was more sensitive to high temperature than Aphis gossypii (Glover). However, the effects of high temperatures on the survival, fecundity, and feeding behavior of these two aphid adults are not clear. This study examined the effect of different temperatures (29 °C, 32 °C, and 35 °C) on the adult survival rate, fecundity, and feeding behavior of these two aphid species. Our results showed that the adverse effects of high temperatures (32 °C and 35 °C) on aphid adult survival and fecundity were greater for Ac. gossypii than Ap. gossypii. The electrical penetration graph (EPG) data showed that Ac. gossypii spent more time feeding on xylem than phloem under all temperature treatments, which contrasted with Ap. gossypii. The time of phloem ingestion by Ap. gossypii at 32 °C was significantly higher than at 29 °C, while for Ac. gossypii, this value significantly decreased when temperature increased. These feeding patterns indicate that Ac. gossypii obtains less nutrition from phloem in support of its development and fecundity. Data generated in this study will serve as the basis for predicting the effects of increased temperature on these two cotton aphids.

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Bertasello, Luiz Eduardo Tilhaqui, Michele Carmo-Sousa, Nathalie K. Prado Maluta, Luciana Rossini Pinto, João R. Spotti Lopes, and Marcos Cesar Gonçalves. "Effect of Sugarcane Cultivars Infected with Sugarcane Yellow Leaf Virus (ScYLV) on Feeding Behavior and Biological Performance of Melanaphis sacchari (Hemiptera: Aphididae)." Plants 10, no. 10 (October 6, 2021): 2122. http://dx.doi.org/10.3390/plants10102122.

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Sugarcane yellow leaf virus (ScYLV), Polerovirus, Luteoviridae, is one of the main viruses that infect sugarcane worldwide. The virus is transmitted by the aphid Melanaphis sacchari in a persistent, circulative manner. To better understand the interactions between ScYLV, sugarcane genotypes and M. sacchari, we explored the effect of sugarcane cultivars on the feeding behavior and biological performance of the vector. The number of nymphs, adults, winged, total number of aphids and dead aphids was assayed, and an electrical penetration graph (EPG) was used to monitor the stylet activities. Multivariate analysis showed changes in the vector’s behavior and biology on cultivars, identifying specific groups of resistance. In the cultivar 7569, only 5.5% of the insects were able to stay longer on sustained phloem ingestion, while in the other seven cultivars these values varied from 20% to 60%. M. sacchari showed low phloem activities in cultivars 7569 and Bio266. Overall, cultivar 7569 showed the worst biological performance of aphids, with the insects presenting mechanical difficulties for feeding and a shorter duration of the phloem period, and thus being considered the most resistant. We conclude that ScYLV virus infection in different sugarcane cultivars induced specific changes in the host plant, modifying the behavior of its main vector, which may favor or impair virus transmission.

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Jin, Liang, Pei-ying Hao, Sheng-zhang Dong, Ya-lin Bian, Ya-lin Bian, and Xiao-ping Yu. "Antifeedant and Insecticidal Effects of Mandelic Acid on the Brown Planthopper Nilaparvata lugens Stål." Zeitschrift für Naturforschung C 66, no. 9-10 (October 1, 2011): 499–506. http://dx.doi.org/10.1515/znc-2011-9-1010.

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To study the effects of mandelic acid (MA) on the brown planthopper (BPH), Nilaparvata lugens, the survival rate and behaviour of BPH fed on an artifi cial diet with different dosages of MA was observed. The survival rate of BPH decreased with the increase of the MA concentration and feeding time. In contrast to the control, the survival rate of BPH 72 h after feeding decreased signifi cantly. Electrical penetration graph (EPG) data indicated that MA absorbed by the rice plant from Kimura B solution signifi cantly affected the feeding behaviour of BPH. At the concentrations of 0.1, 0.5, and 1.0 mg/ml, duration of the phloem ingestion of BPH decreased from 115.34 min (control) to 30.41, 7.63, and 0.36 min, respectively. Periods of xylem ingestion of MA-treated BPH were signifi cantly shorter than those of the control (50.44 min). Moreover, BPH spent more time walking around or being at rest on MA-treated rice plants, as well as in stylet activities. The GST (glutathione S-transferase) activity of BPH increased with the increasing MA concentration, while the GPX (glutathione peroxidases) activity did not change signifi cantly. The results indicate that MA has an antifeedant and insecticidal effect on BPH.

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Wróblewska-Kurdyk, Anna, Katarzyna Dancewicz, Anna Gliszczyńska, and Beata Gabryś. "Antifeedant Potential of Geranylacetone and Nerylacetone and Their Epoxy-Derivatives against Myzus persicae (Sulz.)." Molecules 27, no. 24 (December 13, 2022): 8871. http://dx.doi.org/10.3390/molecules27248871.

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Geranylacetone and nerylacetone are natural sesquiterpenoids, which play various roles in plant-insect interactions, including the deterrent and repellent effects on herbivores. The structural modifications of natural compounds often change their biological activities. The aim of the study was to evaluate the effect of geranylacetone, nerylacetone and their epoxy-derivatives on the probing and settling behavior of Myzus persicae (Sulz.) (Hemiptera: Aphididae). The no-choice test using the Electrical Penetration Graph (EPG) technique showed that the probes before the first phloem phase were usually shorter than 3 min, which means that they were terminated within the epidermis and/or outer layers of mesophyll. This resulted in a tendency to delay the initiation of the phloem phase in aphids, which reflects a weak preingestive deterrent activity of the studied compounds at the level of non-vascular tissues. Most M. persicae showed bouts of sustained phloem sap ingestion. However, the 24-h free-choice test demonstrated that aphids did not settle on the leaves treated with geranylacetone, nerylacetone, and their epoxy-derivatives. The refusal to settle after the consumption of phloem sap on treated plants indicated that the studied compounds had postingestive deterrent activity. The epoxidation of geranylacetone and nerylacetone did not evoke significant changes in their activity profiles.

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Li, Lin, Shuangchao Wang, Xiufen Yang, Frederic Francis, and Dewen Qiu. "Protein Elicitor PeaT1 Efficiently Controlled Barley Yellow Dwarf Virus in Wheat." Agriculture 9, no. 9 (September 6, 2019): 193. http://dx.doi.org/10.3390/agriculture9090193.

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Barley yellow dwarf virus (BYDV), transmitted by the wheat aphid, generates serious wheat yellow dwarf disease and causes great losses in agriculture. Induced resistance has attracted great attention over recent years as a biological method to control plant pathogens and herbivores. Protein elicitor PeaT1 induces defense response in plants against fungi, viruses, and aphids. In this study, wheat seeds and seedlings were soaked and sprayed with 30 μg/mL PeaT1, respectively. Then seedlings were inoculated with BYDV by viruliferous Schizaphis graminum to detect the control efficiency of PeaT1-induced resistance against BYDV. The control efficiency was over 30% on the 14th and 21st days after the inoculation access period. Quantitative real time polymerase chain reaction (Q-RT-PCR) tests showed that there was less mRNA from the BYDV coat protein in PeaT1-treated wheat seedlings than in the control group. Electrical penetration graph (EPG) tests showed that virus transmission vector S.graminum took a longer time to find probe and feeding sites on PeaT1-treated wheat seedlings. Additionally, PeaT1-treated wheat seedlings gained higher plant height and more chlorophyll a&b. These results showed that PeaT1 efficiently controlled BYDV by inhibiting BYDV proliferation, reducing the virus transmission ability of S. graminum and alleviating the symptoms of dwarfism and yellow colouring caused by BYDV. This study provided a new integrated way to control BYDV biologically.

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Ding, Xu, Xi Huang, Litong Sun, Jincai Wu, and Jinglan Liu. "Influence of Abscisic Acid-Biosynthesis Inhibitor Fluridone on the Feeding Behavior and Fecundity of Nilaparvata lugens." Insects 10, no. 2 (February 19, 2019): 57. http://dx.doi.org/10.3390/insects10020057.

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Fluridone (FLU) was a pyrrolidone herbicide that was used for selective weeding in wheat, rice, corn and pasture and was also a biosynthesis inhibitor of abscisic acid (ABA), a significant plant hormone. ABA-promoted callose deposition facilitates rice resistance to pests but whether FLU had the opposite influence was unknown. The effects of FLU on the feeding behavior of the brown planthopper (Nilaparvata lugens Stål; BPH), after feeding with rice plants treated with FLU, were studied, using an electrical penetration graph (EPG). For susceptible rice cultivar (TN1), the duration for which BPH sucked phloem sap (N4 wave duration) after 15 μmol/L of FLU treatment was longer than that of the control but decreased after 30 and 60 μmol/L FLU treatments. Fecundity of BPH treated with 15 μmol/L FLU had no significant change, while the deposition area of callose was significantly decreased. For moderately-resistant rice cultivar (IR42), no differences in BPH feeding behavior and fecundity were observed but the deposition area of callose declined after treated with 15 μmol/L of FLU. These findings suggested that a low concentration of FLU (15 μmol/L) promoted BPH feeding behavior in TN1 but not in IR42 and the response in IR42 appeared to be more complicated, which provided supplementary evidence that ABA promoted plant resistance to BPH.

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Maluta, Nathalie Kristine Prado, João Roberto Spotti Lopes, Elvira Fiallo-Olivé, Jesús Navas-Castillo, and André Luiz Lourenção. "Foliar Spraying of Tomato Plants with Systemic Insecticides: Effects on Feeding Behavior, Mortality and Oviposition of Bemisia tabaci (Hemiptera: Aleyrodidae) and Inoculation Efficiency of Tomato Chlorosis Virus." Insects 11, no. 9 (August 22, 2020): 559. http://dx.doi.org/10.3390/insects11090559.

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Tomato chlorosis virus (ToCV) is a phloem-limited crinivirus transmitted by whiteflies and seriously affects tomato crops worldwide. As with most vector-borne viral diseases, no cure is available, and the virus is managed primarily by the control of the vector. This study determined the effects of the foliar spraying with the insecticides, acetamiprid, flupyradifurone and cyantraniliprole, on the feeding behavior, mortality, oviposition and transmission efficiency of ToCV by B. tabaci MEAM1 in tomato plants. To evaluate mortality, oviposition and ToCV transmission in greenhouse conditions, viruliferous whiteflies were released on insecticide-treated plants at different time points (3, 24 and 72 h; 7 and 14 days) after spraying. Insect mortality was higher on plants treated with insecticides; however, only cyantraniliprole and flupyradifurone differed from them in all time points. The electrical penetration graph (DC-EPG) technique was used to monitor stylet activities of viruliferous B. tabaci in tomato plants 72 h after insecticide application. Only flupyradifurone affected the stylet activities of B. tabaci, reducing the number and duration of intracellular punctures (pd) and ingestion of phloem sap (E2), a behavior that possibly resulted in the lower percentage of ToCV transmission in this treatment (0–60%) in relation to the control treatment (60–90%) over the periods evaluated. Our results indicate that flupyradifurone may contribute to management of this pest and ToCV in tomato crops.

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