1,721,154 research outputs found
DC-EPG raw data on European spittlebugs and sharpshooters feeding behaviour on grapevine
No full textThe Direct Current-Electrical Penetration Graph (DC-EPG) technique was used to compare and describe the feeding behaviour on grapevine of four xylem sap-feeding species considered candidate vectors of X. fastidiosa and widespread in Europe: the meadow spittlebug Philaenus spumarius, the spittlebug Neophilaenus campestris, the rhododendron leafhopper Graphocephala fennahi and the green leafhopper Cicadella viridis. The four species were settled on potted grapevine plants for a period of 6 hours and the feeding activities performed by these insects, from stylet insertion into the plant to withdrawal were recorded by DC-EPG coupled with Stylet+d software. Characteristic waveforms were marked with Stylet+a software and analysed by the macro XylFeed. The raw data of the sequential and non-sequential EPG parameters generated by the XylFeed are reported in this database as part of the connected publication.Peer reviewe
XylFeed – Analysing DC-EPG waveform variables for European spittlebugs and sharpshooters
No full textThe software “XylFeed” is designed as MS Excel macro, developed to analyse essential DC-EPG (Direct Current-Electrical Penetration Graph) waveform variables for European xylem sap-feeding insects (spittlebugs and sharpshooters). DC-EPG waveforms must be manually marked in ‘Stylet+a’ (EPG Systems, Wageningen, Netherlands) or comparable software previously to allow a calculation in “XylFeed”. The software enables the analysis of the probing and feeding activities of European xylem sap-feeding insects through a calculation of sequential and non-sequential EPG variables. A detailed description of the software usage is provided in the Supplementary Material of the connected publication, while software output variables are listed and defined within the software.Peer reviewe
La psila asiática de los cítricos ya se encuentra en el Mediterráneo: amenazas para la citricultura española
No full textCon la detección de la psila asiática, Diaphorina citri en Israel en el pasado mes de julio de 2021 y su establecimiento posterior en una de las regiones más importantes de producción de citricos (Emek Hefer) surge una gran amenaza para toda la citricultura de la cuenca Mediterránea.Peer reviewe
EPG combined with micro-CT and video recording reveals new insights on the feeding behavior of Philaenus spumarius [Dataset]
No full textS1 Video. Correlation between cibarial pump movement and related EPG waveform (Xi). (MP4)The meadow spittlebug Philaenus spumarius plays a key role in the transmission of the bacterium Xylella fastidiosa to olive in Apulia (South Italy). Currently, available data on P. spumarius feeding behavior is limited, and a real-time observation of the different steps involved in stylet insertion, exploratory probes, and ingestion, has never been carried out. Therefore, we performed an EPG-assisted characterization of P. spumarius female feeding behavior on olive, in order to detect and analyze the main EPG waveforms describing their amplitude, frequency, voltage level, and electrical origin of the traces during stylet penetration in plant tissues. Thereafter, each of the main waveforms was correlated with specific biological activities, through video recording and analysis of excretion by adults and excretion/secretion by nymphs. Furthermore, the specific stylet tips position within the plant tissues during each of the waveforms observed was assessed by microcomputer tomography (micro-CT). Additional EPG-recordings were carried out with males of P. spumarius on olive, in order to assess possible sex-related differences. P. spumarius feeding behavior can be described by five main distinct waveforms: C (pathway), Xc (xylem contact/pre-ingestion), Xi (xylem sap ingestion), R (resting), N (interruption within xylem phase). Compared to males, females require shorter time to begin the first probe, and their Xi phase is significantly longer. Furthermore, considering the single waveform events, males on olive exhibit longer np and R compared to females.Peer reviewe
Harnessing the Power of Electrical Penetration Graph Technology to Understand Psyllid-Transmitted Fastidious Bacterial Diseases
No full textSin financiación.Psyllids, also called plant lice, are hemipteran insects that feed on phloem sap. In addition to the direct damage they cause to plants, they are vectors of many phloem-restricted bacterial pathogens belonging to the ‘Candidatus Liberibacter’ spp. and ‘Candidatus Phytoplasma’ spp. from the apple proliferation group (16SrX). Although ‘Candidatus Liberibacter’ spp. cells possess cell walls unlike those of the phytoplasmas, they both share a reduced genome and unavailability in culture. In addition, psyllids transmit both species of bacteria in a persistent, circulative, and propagative manner. Because of the similarity of these pathosystems, the electrical penetration graph (EPG) was employed to study the probing behavior of psyllids. Such studies may assist in understanding the specific interactions between the fastidious bacteria, plant hosts, and insect vectors and lead to innovative control strategies. Herein, we discuss the potential of the EPG to study and understand the tritrophic interactions that secure a successful transmission from plant to plant. In addition, the use of the EPG in evaluating psyllid control strategies including pesticides and tolerant varieties is reviewed.Peer reviewe
EPG combined with micro-CT and video recording reveals new insights on the feeding behavior of Philaenus spumarius [Dataset]
No full textS2 Video. Video obtained from micro-CT showing P. spumarius stylets in xylem vessel. (MKV)The meadow spittlebug Philaenus spumarius plays a key role in the transmission of the bacterium Xylella fastidiosa to olive in Apulia (South Italy). Currently, available data on P. spumarius feeding behavior is limited, and a real-time observation of the different steps involved in stylet insertion, exploratory probes, and ingestion, has never been carried out. Therefore, we performed an EPG-assisted characterization of P. spumarius female feeding behavior on olive, in order to detect and analyze the main EPG waveforms describing their amplitude, frequency, voltage level, and electrical origin of the traces during stylet penetration in plant tissues. Thereafter, each of the main waveforms was correlated with specific biological activities, through video recording and analysis of excretion by adults and excretion/secretion by nymphs. Furthermore, the specific stylet tips position within the plant tissues during each of the waveforms observed was assessed by microcomputer tomography (micro-CT). Additional EPG-recordings were carried out with males of P. spumarius on olive, in order to assess possible sex-related differences. P. spumarius feeding behavior can be described by five main distinct waveforms: C (pathway), Xc (xylem contact/pre-ingestion), Xi (xylem sap ingestion), R (resting), N (interruption within xylem phase). Compared to males, females require shorter time to begin the first probe, and their Xi phase is significantly longer. Furthermore, considering the single waveform events, males on olive exhibit longer np and R compared to females.Peer reviewe
A novel molecular diagnostic method for the gut content analysis of Philaenus DNA
No full text© The Author(s) 2022. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.Philaenus spumarius is a vector of Xylella fastidiosa, one of the most dangerous plants pathogenic bacteria worldwide. There is currently no control measure against this pathogen. Thus, the development of vector control strategies, like generalist predators, such as spiders, could be essential to limit the spread of this vector-borne pathogen. In this study, a polymerase chain reaction (PCR)-based approach was developed to principally detect DNA of P. spumarius in the spider’s gut. Accordingly, 20 primer pairs, targeting the mitochondrial cytochrome oxidase I (COI) and cytochrome b (cytB) genes, were tested for specificity, sensitivity, and efficiency in detecting P. spumarius DNA. Overall, two primer sets, targeting COI gene (COI_Ph71F/COI_Ph941R) and the cytB gene (cytB_Ph85F/cytB_Ph635R), showed the highest specificity and sensitivity, being able to amplify 870 pb and 550 bp fragments, respectively, with P. spumarius DNA concentrations 100-fold lower than that of the DNA of non-target species. Among these two primer sets, the cytB_Ph85F/cytB_Ph635R was able to detect P. spumarius in the spider Xysticus acerbus, reaching 50% detection success 82 h after feeding. The feasibility of this primer set to detect predation of P. spumarius by spiders was confirmed in the field, where 20% of the collected spiders presented positive amplifications.This work was supported by the EU H2020 Research Project XF-ACTORS “Xylella fastidiosa Active Containment Through a multidisciplinary-Oriented Research Strategy” (Grant Agreement 727987) and to the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020). Isabel Rodrigues also acknowledges the PhD research Grant (2020.07051.BD) provided by FCT.Peer reviewe
assisted comparison of European spittlebugs and sharpshooters feeding behaviour on grapevine
Full text linkXylem-feeding is apparently the only requirement making an insect a competent vector of the bacterium Xylella fastidiosa, an organism responsible for the devastation of the Southern Italian olive forest and nowadays considered one of the most feared threats to agriculture and landscape in Europe, including vineyards. Here, we used the direct current-electrical penetration graph (DC-EPG) technique to compare and describe the feeding behaviour on grapevine of four xylem-feeding species considered candidate vectors of X. fastidiosa widespread in Europe, namely two spittlebugs (the meadow spittlebug Philaenus spumarius and the spittlebug Neophilaenus campestris) and two sharpshooter leafhoppers (the rhododendron leafhopper Graphocephala fennahi and the green leafhopper Cicadella viridis). We created a standard for the analysis of EPG waveforms recorded with a DC-EPG device, describing feeding activities performed by these insects from stylet insertion into the plant to withdrawal. This standard, along with freely available software, has been developed to harmonize the calculation of feeding behavioural parameters in xylem-feeders. The most relevant differences between the two vector taxa were the probing frequency and the dynamics of xylem ingestion. Sharpshooters tended to perform significantly more probes than spittlebugs. In contrast, the latter spent longer times in low-frequency xylem ingestion, characterized by scattered contractions of the cibarial dilator muscle interspersed with periods of pump inactivity. Cicadella viridis was the species displaying the highest frequency of the electrical pattern found to be associated with X. fastidiosa inoculation in spittlebugs (Xe). Feeding behavioural data presented here represent an important step forward for deepening our knowledge of xylem-sap feeding insects' interaction with both the host plants and the bacterium they transmit
Identification, distribution and vector population dynamics of Barley yellow dwarf virus in three cereal‐producing areas of Spain
No full textELISA‐based surveys during 1985–87 in three major cereal‐growing areas of Spain confirmed the presence of barley yellow dwarf virus (BYDV). Samples of small grain cereals and grasses with and without BYDV‐like symptoms were collected in the central, southwestern, and northeastern Spain. Infections were found in all cereal species sampled and in some grasses. About 37 % of the samples collected in 1985 were infacted with isolates of the PAV serotype. Isolates of the RPV serotype were less common, and were detected only in samples from the central region at El Encin, Madrid. Only a single sample, collected from El Encin in 1987, was unequivocally diagnosed as containing an isolate of the MAV serotype. Aphid vector population dynamics was monitored during fall and winter of 1984–87 in the central region. Rhopalosiphum padi L. appeared to be the most abundant species during fall and winter months, infesting grasses and volunteer wheat. Other species present were Sitobion avenae (F.), Metopolophium dirhodum (Walker) and Rhopalosiphum maidis (Fitch). Both R. padi and S. avenae seem to be anholocyclic in the central region of Spain, and are able to remain and reproduce on wheat volunteers and grasses until the beginning of spring. S, avenae populations increase quickly on wheat volunteers in April, while populations of R. padi remain low. Therefore, spread of S. avenae‐transmitted BYDV types to neighbouring cereal fields seem more likely to occur than spread of other types. Other possible virus reservoirs, such as maize, also need investigation for a better understanding of BYDV epidemiology in the central and other cercal‐growing areas of Spain. Copyright © 1989, Wiley Blackwell. All rights reserve
Philaenus spumarius: when an old acquaintance becomes a new threat to European agriculture
No full textThe unique color pattern polymorphism and the foamy nymphal case of the meadow spittlebug Philaenus spumarius have
attracted the attention of scientists for centuries. Nevertheless, since this species has never been considered a major threat to
agriculture, biological, ecological and ethological data are missing and rather scattered. To date this knowledge has become
of paramount importance, in view of the discovery of P. spumarius main role in the transmission of the bacterium Xylella
fastidiosa in Italy, and possibly in other European countries. The aim of this review is to provide a state of the art about this
species, with particular focus on those elements that could help developing environmental friendly and sustainable control
programs to prevent transmission of X. fastidiosa. Moreover, recent findings on the role of the meadow spittlebug as vector
of the fastidious bacterium within the first reported European bacterium outbreak in Apulia (South Italy) will be discussed
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