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Fast and effective monitoring and surveillance techniques are crucial for the swift implementation of control methods to prevent the spread of Huanglongbing, a devastating citrus disease, and its invasive psyllid vector, Asian citrus psyllid, Diaphorina citri, into South Africa, as well as to control the native vector, African citrus triozid, Trioza erytreae. Monitoring for citrus psyllid pests can be improved by using semiochemical odorants to augment already visually attractive yellow sticky traps. However, environmental variables such as temperature and humidity could influence odorant release rates. Five field cages were used to test the ability of a selection of odorants to improve yellow sticky trap efficacy in capturing citrus psyllids. Environmental effects on odorant loss from the dispensers were also investigated. The odorants that most improved yellow sticky trap captures in field cages were then tested under open field conditions alongside lower concentrations of those same lures. Gas chromatography-mass spectrometry was used to calculate odorant release rates as well as to determine if any contamination occurred under field conditions. None of the odorants under field cage or field conditions significantly improved psyllid capture on yellow sticky traps. Temperature influenced odorant loss, and release rate from polyethylene bulbs decreased over time. Based on these results, the use of unbaited yellow sticky traps seems to be the most effective method for monitoring of Huanglongbing vectors. [ABSTRACT FROM AUTHOR]

Cyamophila willieti (Hemiptera: Psyllidae) is a significant pest that adversely affects the growth of Styphnolobium japonicum and its variant, Styphnolobium japonicum f. pendula. Despite its impact, research on this species remains limited. In this study, we successfully assembled a chromosome-level genome for Cyamophila willieti using a comprehensive approach that integrated Illumina sequencing, PacBio sequencing, and Hi-C technology. The genome size was determined to be 361.61 Mb, with a scaffold N50 length of 28.90 Mb. Additionally, the genome was mapped to 13 chromosomes (N = 12 A + X), and a total of 15,841 genes were predicted, with 90.38% of them functionally annotated. In summary, the high-quality genome of Cyamophila willieti provides valuable data to support further research, including pest management strategies. [ABSTRACT FROM AUTHOR]

Sternorrhyncha, one of the four major suborders of Hemiptera, is a phytophagous taxon inclusive of nearly 18 000 described species. The phylogenetic relationships within the taxon and the earliest‐branching lineage of its infraorders remain incompletely understood. This study attempted to illuminate the phylogenetic relationships within Sternorrhyncha through the use of maximum likelihood, Bayesian inference and maximum parsimony analyses, employing ultraconserved element (UCE) data from 39 genomic and 62 transcriptomic datasets and thereby representing most families within the taxon. The probe set Hemiptera 2.7Kv1 was used to recover a total of 2731 UCE loci: from 547 to 1699 (with an average of 1084) across all genomic datasets and from 108 to 849 (with an average of 329) across all transcriptomic datasets. All three types of phylogenetic analyses employed in this study produced robust statistical support for Sternorrhyncha being a monophyletic group. The different methods of phylogenetic analysis produced inconsistent descriptions of topological structure at the infraorder level: while maximum likelihood and Bayesian inference analyses produced strong statistical evidence (100%) indicating the clade Psylloidea + Aleyrodoidea to be a sister of the clade Aphidoidea (Aphidomorpha) + Coccoidea (Coccomorpha), the maximum parsimony analysis failed to recover a similar result. Our results also provide detail on the phylogenetic relationships within each infraorder. This study presents the first use of UCE data to investigate the phylogeny of Sternorrhyncha. It also shows the viability of amalgamating genomic and transcriptomic data in studies of phylogenetic relationships, potentially highlighting a resource‐efficient approach for future inquiries into diverse taxa through the integration of varied data sources. [ABSTRACT FROM AUTHOR]

Urban trees offer many ecosystem services which can be affected by pathogens, including phytoplasmas. Phytoplasmas cause regulator growth imbalances in infected plants, which produce deviations from the normal plant architecture, among other symptoms. In Bogotá, Colombia, 'Candidatus Phytoplasma asteris' and 'Candidatus Phytoplasma fraxini' infect at least 11 species of urban trees, including Andean oak. This tree species is endemic to Colombia and Panama, and it plays an important ecologic role in the Colombian Andes wild forests. In Bogotá, knowledge about the insect vectors associated with the transmission of phytoplasmas to Andean oak is scarce. In this work we sampled the entomofauna of Andean oaks and evaluated the role of Cicadellidae and Psylloidea taxa as potential vectors of phytoplasmas in Bogotá. Insects were captured using direct and indirect sampling methods from Andean oaks at three contrasting sites in Bogotá, and also from neighbouring trees. The insects were identified by morphological and molecular methods and tested for phytoplasmas. In total, 510 Cicadellidae members of 13 taxa and 129 Psylloidea of 8 taxa were captured; richness and abundance depended on the type and sampling site. The most abundant species were Scaphytopius (Convelinus) sp. (Cicadellidae) and Acizzia uncatoides (Psylloidea). Leafhoppers positive for phytoplasmas were Chiasmodolini, Dikrella (Readionia) sp., Empoasca sp. and Scaphytopius sp. taxa. Our results suggest that several potential species of phytoplasmas may be dispersing phytoplasmas to Andean oaks and other urban tree species. It is necessary to conduct transmission tests to evaluate the transmission capacity of the potential vectors. [ABSTRACT FROM AUTHOR]

Agonoscena pistaciae (Hemiptera: Psyllidae) is a significant pest in pistachio (Pistacia vera L.) orchards in Türkiye. This study aimed to evaluate the effectiveness of yellow sticky traps as an alternative method for controlling A. pistaciae populations in pistachio orchards. Conducted in late September and early October of 2021 and 2022, during peak pest activity, the experiment was carried out in Siirt, with three replicates following a randomized block design. Five traps were hung on all sides of each tree for sampling. Repeated measures ANOVA (repeated measures; general linear model) was used to observe changes over time. The results indicated that yellow sticky traps were highly effective in mass trapping adults, capturing an average maximum of 12 332.67 adults per trap. A significant decrease in the number of nymphs and eggs on the leaves was observed in the yellow sticky trap-treated trees compared to the control plots by mid-October (P < 0.05). Specifically, the average number of nymphs per composite leaf dropped from 24.95 to 11.23 in 2021, and from 145.18 to 27.29 in 2022. Similarly, the average number of eggs per composite leaf decreased from 61.18 to 2.29 in 2021, and from 73.56 to 3.64 in 2022. These findings suggest that yellow sticky traps can significantly reduce psyllid populations in pistachio orchards over the long term and can be an effective control method when used early in the vegetative period for low- to medium-sized psyllid populations. [ABSTRACT FROM AUTHOR]

Imidacloprid is a neonicotinoid insecticide used for managing the Asian citrus psyllid, Diaphorina citri Kuwayama, which serves as vector of phytopathogens causing citrus greening. However, development of resistance to neonicotinoids among populations of D. citri has coincided with occasional control failures in the field. The objectives of this research were to (1) survey current levels of imidacloprid resistance in Florida citrus; (2) compare feeding behavior between imidacloprid‐resistant and susceptible D. citri using electrical penetration graph recordings, and (3) investigate the possible amplification of insecticide hormoligosis associated with resistance. Field surveys confirmed that the susceptibility of D. citri populations to imidacloprid has decreased in commercial Florida citrus groves compared with a laboratory‐susceptible population. Following 12 generations of selection, resistance to imidacloprid increased by 438 fold compared with the susceptible strain. Imidacloprid‐susceptible D. citri feeding on citrus exhibited significantly more bouts associated with intercellular pathway (C), phloem penetration (D), phloem salivation (E1), and nonprobing (Np) activities than imidacloprid‐resistant counterparts. However, there were no differences observed in the frequency or duration of phloem ingestion or xylem feeding between susceptible and resistant D. citri. There was no statistical difference in fecundity between resistant and susceptible strains. However, the fecundity of imidacloprid‐susceptible female D. citri treated with a sublethal concentration of imidacloprid (LC25) increased significantly compared with controls, while such hormoligosis was less pronounced among imidacloprid‐resistant psyllids. Our results suggest that imidacloprid‐resistant psyllids may cease feeding sooner than susceptible counterparts following sublethal exposure to this insecticide, indicative of a behavioral resistance mechanism. [ABSTRACT FROM AUTHOR]

(1) Background: Mitochondrial genomes are important markers for the study of phylogenetics and systematics. Triozidae includes some primary pests of Populus euphratica. The phylogenetic relationships of this group remain controversial due to the lack of molecular data. (2) Methods: Mitochondria of Egeirotrioza Boselli were sequenced and assembled. We analyzed the sequence length, nucleotide composition, and evolutionary rate of Triozidae, combined with the 13 published mitochondrial genomes. (3) Results: The evolutionary rate of protein-coding genes was as follows: ATP8 > ND6 > ND5 > ND2 > ND4 > ND4L > ND1 > ND3 > APT6 > CYTB > COX3 > COX2 > COX1. We reconstructed the phylogenetic relationships of Triozidae based on 16 triozid mitochondrial genomes (thirteen ingroups and three outgroups) using the maximum likelihood (ML) and Bayesian inference (BI) approaches. The phylogenetic analysis of the 16 Triozidae mitochondrial genomes showed that Egeirotrioza was closely related to Leptynoptera. (4) Conclusions: We have identified 13 PCGs, 22 tRNAs, 2 rRNAs, and 1 control region (CR) of all newly sequenced mitochondrial genomes, which were the mitochondrial gene type in animals. The results of this study provide valuable genomic information for the study of psyllid species. [ABSTRACT FROM AUTHOR]

Introduction: Pear decline (PD) is one of the most devastating diseases of Pyrus communis in Europe and North America. It is caused by the pathogen 'Candidatus Phytoplasma pyri' and transmitted by pear psyllids (Cacopsylla pyri, C. pyricola, and C. pyrisuga). Identifying attractant and repellent volatile organic compounds (VOCs) could improve the development of alternative plant protection measurements like push-pull or attract-and-kill strategies against pear psyllids. Our objective was to investigate which chemical cues of the host plant could influence the host-seeking behavior of pear psyllids, and if cedarwood (CWO) and cinnamon bark (CBO) essential oils could serve as repellents. Results and discussion: Based on the literature, the five most abundant VOCs from pear plants elicited EAG responses in both C. pyri and C. pyrisuga psyllid species. In Y-olfactometer trials, single compounds were not attractive to C. pyri. However, the main compound mixture was attractive to C. pyri and C. pyrisuga females. CWO and CBO were repellent against C. pyri, and when formulated into nanofibers (NF), both were repellent in olfactometer trials. However, CBO nanoformulation was ineffective in masking the odors of pear plants. In a field trial, attractive, repellent CWO and blank formulated NF were inserted in attractive green sticky traps. C. pyri captures in traps with CWO NF were statistically lower than in traps with the attractive mixture. Nevertheless, no statistical differences in the numbers of caught specimens were observed between CWO NF and those captured in green traps baited with blank NF. Transparent traps captured fewer psyllids than green ones. In a second field study with a completed different design (push-and-count design), dispensers filled with CBO were distributed within the plantation, and attractive green sticky traps were placed around the plantation. The numbers of trapped pear psyllids increased significantly in the border of the treated plantation, showing that psyllids were repelled by the EOs in the plantation. Although further field evaluation is needed to assess and improve their effectiveness, our results show that these aromatic compounds, repellent or attractive both in nanoformulations and marking pen dispensers, offer great potential as an environmentally sustainable alternative to currently applied methods for managing pear decline vectors. [ABSTRACT FROM AUTHOR]

Simple Summary: The psyllid genus Primascena was erected for a fossil species from Dominican amber, P. subita. As the single known specimen of this species is a partly damaged male, the description was quite incomplete. Recently, two undescribed species were discovered in Brazil (Mato Grosso do Sul) that are ascribed to this genus. The extant species allow the description of the previously unknown female and immature, and to complete information on the morphology of the male. A cladistic morphological analysis confirms the position of the genus in the subfamily Aphalaroidinae and supports the monophyly of the fossil and the two extant species. The extant Primascena species develop on plants of the Polygonaceae: Eriogonoideae, an unusual psyllid host, shared by only one other species of the same subfamily. Aphalaroidinae is most species-rich in the neotropics, with nine out of 13 genera being restricted to South America. Fossils can document the morphological diversification through time and date lineages, providing relevant characters are preserved. Primascena Klimaszewsi, 1997 was erected for P. subita Klimaszewsi, 1997 on the basis of a single, partly damaged male from Dominican amber. Originally assigned to Rhinocolidae: Paurocephalinae, the genus was subsequently transferred to Psyllidae: Aphalaroidinae. Recently, two undescribed species resembling the fossil species were discovered in Brazil (Mato Grosso do Sul), allowing a detailed morphological study of adults and immatures. Based on the morphological study, a revised diagnosis of the genus is provided, including the previously unknown female and fifth instar immatures. Primascena subita is redescribed and P. empsycha n. spec. and P. ruprechtiae n. spec. are formally described and illustrated. An identification key is provided for the species of Primascena. A cladistic morphological analysis supports the placement of the two new species in Primascena, and of this genus in the Aphalaroidinae. It is sister to all but Aphalaroida, though with little support. The two Brazilian species develop on Ruprechtia spp. (Polygonaceae: Eriogonoideae), an unusual psyllid host. Immatures of P. ruprechtiae are free-living on the lower leaf face and do not induce galls. [ABSTRACT FROM AUTHOR]

Using molecular (COI , Cytb , H3 , wg , 12S, 16S, and 28S) and morphological data (61 characters of adults and immatures), the phylogenetic relationships of the 20 nominal genera of Liviinae were analysed, and the monophyly of the subfamily was tested relative to the other two subfamilies of Liviidae. The analyses of the molecular, morphological, and combined datasets provided similar results with a strong or moderate support in the molecular and combined analyses for the subfamilies of Liviidae and two clades in Liviinae given tribal rank (Liviini and Paurocephalini stat. rev.). Three of the six previously recognized genera were confirmed as monophyletic (Aphorma , Camarotoscena , and Livia) and three were shown to be polyphyletic: Diclidophlebia s.l. (Diclidophlebia s.s. , Haplaphalara stat. rev. Klyveria Burckhardt, Serbina and Malenovský, gen. nov. Melanastera Serbina, Malenovský, Queiroz and Burckhardt, gen. nov. and Woldaia stat. rev.), Paurocephala s.l. (Liella Burckhardt, Serbina and Malenovský, gen. nov. and Paurocephala s.s.), and Syntomoza s.l. (Anomoterga stat. rev. and Syntomoza s.s.). The new generic definitions require 38 new and eight revived combinations, including the transfer of two species to other families. All genera of Liviinae are diagnosed and keys are provided for their identification. A checklist of world Liviinae is supplemented. [ABSTRACT FROM AUTHOR]

The goji berry psyllid, Bactericera gobica Logniova (Homoptera: Psyllidae), is one of the most important pests on goji berry plants (Lycium barbarum L.), whose fruits are widely used in traditional Chinese medicine and food. However, chemical control is still the predominant control strategy of this pest. Recently, two species of predatory mites, Neoseiulus setarius Ma, Meng & Fan and Neoseiulus barkeri Hughes were found to be associated with B. gobica in China. To assess their predation potential against B. gobica, the functional responses of these two phytoseiid species feeding on different densities (2, 4, 8, 12, 16, 24 and 32 individuals) of B. gobica eggs and 1st instar nymphs were compared at a temperature of 25ºC ± 1º C. Logistic regression analysis revealed that both predatory mite species exhibited type Holling-II functional responses on eggs and 1st instar nymphs of B. gobica, with the predation number increased for both predators as the density of prey increased. Overall, N. setarius consumed more prey compared to N. barkeri across all levels of prey densities. Meanwhile, the highest attack rate (α = 0.0283), the lowest handling time (Th = 1.1324 h prey− 1), and the highest estimated maximum predation rate (T/Th = 21.19 prey day− 1) were all observed for N. setarius fed with 1st instar nymphs of B. gobica. These findings suggest that it is worthy considering utilizing N. setarius and N. barkeri as candidate biocontrol agents of B. gobica, with N. setarius appearing to be a more effective predator than N. barkeri. [ABSTRACT FROM AUTHOR]

Simple Summary: Huanglongbing (HLB) is the most devastating citrus disease across Africa, America and Asia. It is associated with three species of bacteria belonging to the genus 'Candidatus Liberibacter', transmitted by the psyllid vector Trioza erytreae, among others. This insect has spread throughout part of the Iberian Peninsula, threatening citrus orchards with the possible arrival and transmission of HLB. Currently, there are no curative methods of control for the disease, so finding plant material less suitable for psyllids can reduce the risk of spreading. We have evaluated how the citrus combination, rootstocks (Flying dragon, 'Cleopatra' mandarin, Carrizo citrange, Forner-Alcaide no.5, Forner-Alcaide no.517 and Citrus macrophylla) and scion cultivars ('Star Ruby', 'Clemenules', 'Navelina', 'Valencia Late', 'Fino 49' and 'Ortanique') determine the biology of T. erytreae. Our results show that T. erytreae behaves differently depending on the combination, and is the least suitable for its survival with 'Ortanique' on Forner-Alcaide no. 517 and 'Valencia Late' on Carrizo citrange. The psyllid preferred 'Fino 49' grafted onto Carrizo citrange for egg laying rather than Flying Dragon. Trioza erytreae (Del Guercio, 1918) (Hemiptera: Triozidae) is a citrus pest which produces gall symptoms on leaves and transmits bacteria associated with the citrus disease Huanglongbing, 'Candidatus Liberibacter' spp. In the present work, the biology and behaviour of T. erytreae were studied in different rootstock–cultivar combinations. Six rootstocks were used, Flying dragon (FD), 'Cleopatra' mandarin (CL), Carrizo citrange (CC), Forner-Alcaide no.5 (FA5), Forner-Alcaide no.517 (FA517) and Citrus macrophylla (CM), and six scion cultivars: 'Star Ruby', 'Clemenules', 'Navelina', 'Valencia Late', 'Fino 49' and 'Ortanique'. Survival and oviposition were evaluated in a no-choice trial, and preference in a choice trial, all of them under greenhouse conditions. Trioza erytreae did not show a clear settle preference for any citrus combination. However, it was able to lay more eggs in 'Fino 49' grafted on CC than on FD. In terms of survival, 'Ortanique' grafted onto FA5 was more suitable than when grafted onto FA517, and in the case of 'Valencia Late', when it was grafted onto CM rather than CC. Our results showed that T. erytreae behave differently depending on the citrus combination. [ABSTRACT FROM AUTHOR]

The electrical penetration graph (EPG) technique is the most powerful tool for studying the feeding behavior of pierce-sucking insects. However, calculating EPG variables is often very time-consuming, and consequently, several software programs have been developed for the automatic calculation of EPG variables. Here we present a new user-friendly Excel Workbook that uses a standardized list of EPG variables and follows expert guidelines for calculating them. The program developed in Visual Basic for Applications (VBA) is a step up from the existing software and allows easy data analysis and interpretation. It also includes a novel option for dealing with the common problem of "truncated"—waveforms artificially terminated by the end of recording. The only requirement to run the program is Microsoft Excel software running under a PC environment. The Workbook was validated by calculating variables from EPG recordings of aphids and psyllids and the results obtained were compared with those of existing software such as the Sarria Workbook. Our EPG Workbook provides researchers with a reliable and standardized tool for the automatic calculation of up to 127 EPG variables from phloem-sap-sucking insects. [ABSTRACT FROM AUTHOR]

In a survey of the arthropod fauna of 33 Urban Green Spaces (UGS) in Bogotá, Colombia, between 2017 and 2019, 21 species (3,825 specimens) of Psylloidea were collected. These represent all seven recognised families of jumping plant-lice and include seven species identified only to genus. The specimens, all adults, were collected on 30 plant species used for arborization in the UGS. Two species are described as new (Mastigimas longicaudatus Rendón-Mera, Burckhardt & Vargas-Fonseca, sp. nov. and Leuronota albilinea Rendón-Mera, Burckhardt & Vargas-Fonseca, sp. nov.), one species is redescribed (Mastigimas colombianus Burckhardt, Queiroz & Drohojowska) and one species is recorded for the first time from Colombia (Calinda trinervis Olivares & Burckhardt). Among the seven species identified only to genus is an undescribed species of Melanastera, representing a genus not previously known from Colombia. Fourteen species found during the survey are probably native (66%) and seven (33%) adventive. Our findings highlight the significance of UGS for preservation of biological diversity and stress the importance of using native plants in urban landscape planning for the conservation of the native entomofauna. [ABSTRACT FROM AUTHOR]

Background: Carrot is an important vegetable crop grown worldwide. The major economic problem in carrot cultivation is yellow disease caused by Bactericera trigonica, which induces biotic stress and has the greatest impact on crop productivity. Comprehensive studies on the mechanism of carrot defense response to biotic stress caused by B. trigonica infestation have yet to be conducted. Methods: The changes in photosynthetic pigments, proline, TPC, H2O2 and MDA content, DPPH radical scavenging ability, and antioxidant enzyme activity of SOD, CAT, and POX in carrot leaves in response to insect sex (female and male), rapid response (during the first six hours), and long-term response to B. trigonica infestation were evaluated. Results: The results of our study strongly suggest that B. trigonica infestation causes significant changes in primary and secondary metabolism and oxidative status of carrot leaves. Photosynthetic pigment content, TPC, and DPPH and CAT activities were significantly reduced in carrot leaves in response to insect infestation. On the other hand, proline, H2O2 content, and the activity of the antioxidant enzymes superoxide dismutase and peroxidase were increased in carrot leaves after B. trigonica infestation. The results indicate that B. trigonica attenuates and delays the oxidative stress responses of carrot, allowing long-term feeding without visible changes in the plant. Carrot responded to long-term B. trigonica infestation with an increase in SOD and POX activity, suggesting that these enzymes may play a key role in plant defense mechanisms. Conclusions: This is the first comprehensive study strongly suggesting that B. trigonica infestation causes significant changes in primary and secondary metabolism and an attenuated ROS defense response in carrot leaves that enables long-term insect feeding. The information provides new insights into the mechanisms of carrot protection against B. trigonica infestation. [ABSTRACT FROM AUTHOR]

The accessible literature covered in this paper commonly highlights psyllids as a significant group of insects affecting pear trees, posing a continual challenge for commercial orchards. With the development of modern pear cultivation systems, Cacopsylla pyri Linnaeus 1758 (Hemiptera: Psyllidae) has emerged as a major pest in pear orchards across many European countries, including those in the Western Balkans. For years, the agricultural sector has primarily relied on chemical insecticides to control pear psyllas, but these methods often fail to produce satisfactory results. This is largely due to C. pyri's rapid development of resistance to chemical treatments. Consequently, modern agriculture is increasingly shifting towards biological methods to manage C. pyri, involving the identification and conservation of its natural enemies. Although there is an abundance of research on the natural predators of C. pyri and their biocontrol applications across the globe, the Western Balkan region has conducted relatively few studies on the subject. Globally, various parasitoids, predators, and entomopathogenic fungi are often cited as effective against C. pyri. Specific species registered in the agroecological conditions of the Western Balkans include parasitic wasps such as Trechnites insidiosus Crawford, 1910 (Hymenoptera: Encyrtidae) and Prionomitus mitratus Dalman, 1820 (Hymenoptera: Encyrtidae), as well as the predatory bug Anthocoris nemoralis Fabricius, 1794 (Hemiptera: Anthocoridae). However, most Balkan countries have yet to fully utilise the potential of beneficial entomofauna or develop strategies for their commercial application at a national level. Considering that C. pyri is a major pest in pear cultivation and its natural enemies have not been thoroughly explored in most of the Western Balkans, this paper aims to review the literature data on available natural enemies of pear psyllas and to highlight and promote their undeniable potential in biological control. [ABSTRACT FROM AUTHOR]

Melanastera sinica He & Burckhardt, sp. nov., a new psylloid species developing on Grewia sp., is described from Hainan, China. It is the first Melanastera species reported from Asia and China, and the second species from the Old World. While New World species of Melanastera are mostly associated with the plant families Melastomataceae and Annonaceae, the two Old World species develop on the malvaceous Grewia, a host otherwise used in psylloids by two Haplaphalara species. The new species is described, diagnosed and illustrated, and its host plant and biogeographic ranges are discussed. [ABSTRACT FROM AUTHOR]

An investigation of viruses circulating in populations of field and laboratory potato/tomato psyllids (Bactericera cockerelli) was conducted using high-throughput sequencing (HTS) technology and conventional RT-PCR. Three new viruses were discovered: one from the family Tymoviridae and two from the family Solemoviridae. A tymo-like virus sequence represented a nearly complete 6843 nt genome of a virus named Bactericera cockerelli tymo-like virus (BcTLV) that spanned five open reading frames (ORFs) which encoded RNA-dependent RNA polymerase (RdRP), helicase, protease, methyltransferase, and a capsid protein. Phylogenetic analyses placed the RdRP of BcTLV inside a divergent lineage of the viruses from the family Tymoviridae found in insect and plant hosts in a sister clade to the genera Tymovirus, Marafivirus, and Maculavirus. Four solemo-like virus sequences were identified in the HTS outputs, representing two new viruses. One virus found only in field-collected psyllids and named Bactericera cockerelli solemo-like virus 1 (BcSLV-1) had a 5479 nt genome which spanned four ORFs encoding protease and RdRP. Three solemo-like sequences displayed 87.4–99.7% nucleotide sequence identity among themselves, representing variants or strains of the same virus named Bactericera cockerelli solemo-like virus 2 (BcSLV-2). The genome of BcSLV-2 spanned only two ORFs that encoded a protease and an RdRP. Phylogenetic analysis placed the RdRPs of BcSLV-1 and BcSLV-2 in two separate lineages as sister clades to viruses from the genus Sobemovirus found in plant hosts. All three new psyllid viruses were found circulating in psyllids collected from potato fields in southern Idaho along with a previously identified Bactericera cockerelli picorna-like virus. Any possible role of the three viruses in controlling populations of the field psyllids remains to be elucidated. [ABSTRACT FROM AUTHOR]

A molecular survey of native and adventive psyllids in the central Macaronesian islands provides the first comprehensive phylogenetic assessment of the origins of the psyllid fauna of the Canary and Madeira archipelagos. We employ a maximum likelihood backbone constraint analysis to place the central Macaronesian taxa within the Psylloidea mitogenome phylogeny. The native psyllid fauna in these central Macaronesian islands results from an estimated 26 independent colonization events. Island host plants are predicted by host plants of continental relatives in nearly all cases and six plant genera have been colonized multiple times (Chamaecytisus, Convolvulus, Olea, Pistacia, Rhamnus, and Spartocytisus) from the continent. Post-colonization diversification varies from no further cladogenesis (18 events, represented by a single native taxon) to modest in situ diversification resulting in two to four native taxa and, surprisingly, given the diverse range of islands and habitats, only one substantial species radiation with more than four native species. Specificity to ancestral host plant genera or family is typically maintained during in situ diversification both within and among islands. Characterization of a recently discovered island radiation consisting of four species on Convolvulus floridus in the Canary Islands shows patterns and rates of diversification that reflect island topographic complexity and geological dynamism. Although modest in species diversity, this radiation is atypical in diversification on a single host plant species, but typical in the primary role of allopatry in the diversification process. [ABSTRACT FROM AUTHOR]

The article offers information on the species Oliarus beebei described by Z. P. Metcalf in 1945. Oliarus beebei was described from one male specimen and four female specimens. It was found that Oliarus beebei belonged to the genus Mnemosyne Stål, a supposition confirmed by a review of the original description. The figures of Oliarus beebei in Metcalf depict the species as having three carinae on the mesonotum.

Simple Summary: The pear psyllids comprise over 20 species of small, sap-feeding insects which include several of the most damaging pests in commercial pear orchards of Europe, temperate Asia, and the Americas. Efforts to control these pests historically have centered on the use of insecticides. Because psyllid outbreaks often may be prompted by insecticidal destruction of natural enemies, pear growers have begun to substitute biological control and conservation of natural enemies for some insecticide applications. Conservation of natural habitats to make alternative resources (prey and hosts) available to natural enemies of crop pests increasingly is being examined as a tactic for strengthening biological control in crops. This review shows that psyllids in natural habitats are important resources for species of predators and parasites which provide biocontrol of pear psyllids. Traits which affect suitability of non-pest psyllids to beneficials include how closely related they are to pear psyllids and type of seasonal life cycle, the latter shown to govern when (seasonally) non-pest psyllids in natural habitats are available to beneficials. Confirmation that natural habitats and these alternative resources lead to numerical increases in beneficials in orchards requires proof that key predators and parasites colonize orchards from natural habitats. Difficulties in obtaining this proof are discussed. The pear psyllids (Cacopsylla spp.; Psylloidea) comprise ~24 species of sap-feeding insects distributed in Europe, temperate Asia, and (as introductions) in the Americas. These pear-specialized insects are among the most damaging and difficult to control pests in orchards. Biological control increasingly is being used to replace or partially replace insecticidal management of pear psyllids. Many key natural enemies of pear psyllids regularly occur in non-orchard habitats on native plants. The presence of beneficial species both in orchard and non-orchard habitats (here referred to as "spillover") has prompted suggestions that native plants and their associated psyllids should be conserved as alternative resources for natural enemies of pear psyllids. The expectation is that the natural enemies will move from those habitats into psyllid-infested orchards. This review shows that psyllids in native habitats are important resources for several key predators and parasitoids of pear psyllids. These resources are critical enough that some beneficials exhibit an almost nomadic existence as they move between plant species, tracking the seasonal appearance and disappearance of psyllid species. In contrast, other natural enemies show minimal or no spillover between orchard and non-orchard habitats, which likely is evidence that they exhibit limited movement at best between orchard and non-orchard habitats. To show conclusively that spillover also indicates that a beneficial species disperses between native habitats and orchards requires difficult research on insect movement. This review concludes with a brief discussion of these difficulties and possible solutions. [ABSTRACT FROM AUTHOR]

Simple Summary: The cultivation of leek in Castile and Leon is located in the provinces of Segovia and Valladolid, which accounts for the largest production of this crop in Spain. In 2015, growers became concerned by severe damage to leek crops, tentatively attributed to the onion and leek psyllid, Bactericera tremblayi. For effective integrated pest management in leek fields, it is essential to understand the biology of this species and the factors influencing its development. This study revealed that B. tremblayi predominated as the primary species of jumping plant-lice in leek crops throughout the entire crop cycle, from May–July to harvest (September–November). The maximum peaks of B. tremblayi were observed at the end of the crop cycle, particularly during late-season cycles characterized by lower mean temperatures. Under controlled conditions, B. tremblayi exhibited its complete development from the egg stage to adult within the temperature range of 15 to 25 °C. Notably, when the temperature exceeded the threshold of 30 °C, B. tremblayi did not complete its developmental cycle. The optimum temperature for the development of B. tremblayi was close to 24 °C. The findings of this study significantly contribute to the development of rational population management strategies for B. tremblayi. This knowledge plays a crucial role in mitigating the potential impact of this species on agricultural systems. Bactericera tremblayi (Wagner, 1961) (Hemiptera: Triozidae), the onion and leek psyllid, belongs to the Bactericera nigricornis Förster complex, along with B. trigonica and B. nigricornis. In contrast to the other two species, there has been a notable absence of studies examining the distribution and seasonal occurrence of B. tremblayi, despite its association with significant issues in leek crops. Surveys were conducted between 2017 and 2020 in the main leek-growing area of Castile and Leon (Spain). An extensive survey encompassing 29 distinct plots was monitored with sweep nets and visual inspection, counting plants with immature forms at three times in the crop cycle. Additionally, a total of seven seasonal monitoring surveys were conducted in the same area of study. Plots were monitored every ten days, employing three distinct sampling methods including horizontal green tile water traps, sweep nets, and visual inspection, counting the juvenile stages by plant. The results revealed that B. tremblayi predominated as the primary species of jumping plant-lice in leek crops throughout the entire crop cycle. To date, there exists no documented incidence of pathogenic agents within symptomatic leeks. Consequently, the manifestation of severe symptoms is highly likely to be a direct consequence of the feeding activity of the onion psyllid. Populations of B. tremblayi were present in leek crops from May–July to harvest (September–November). Adults were captured in horizontal green water traps several days before they were found in sweep net samples, making the former effective in capturing early immigrant individuals. The maximum peaks of B. tremblayi were observed at the end of the crop cycle, particularly during late-season cycles characterized by lower mean temperatures. During observations made in a controlled environment, temperature exerted a significant influence on the developmental time of all stages of B. tremblayi. The complete development from egg to adult occurred within a temperature range of 15 to 25 °C. At 30 °C, the survival of eggs and N1 nymphs was limited and B. tremblayi did not complete its developmental cycle. The optimum temperature for the development of B. tremblayi provided by the models used was close to 24 °C with the application of Briere, Taylor, and Lactin models and around 21 °C with the SSI model. These results provided a good adjustment in predicting the survival patterns of B. tremblayi under the studied environmental conditions. [ABSTRACT FROM AUTHOR]

Assessing different levels of red gum lerp psyllid (Glycaspis brimblecombei) can influence the hyperspectral reflectance of leaves in different ways due to changes in chlorophyll. In order to classify these levels, the use of machine learning (ML) algorithms can help process the data faster and more accurately. The objectives were: (I) to evaluate the spectral behavior of the G. brimblecombei attack levels; (II) find the most accurate ML algorithm for classifying pest attack levels; (III) find the input configuration that improves performance of the algorithms. Data were collected from a clonal eucalyptus plantation (clone AEC 0144—Eucalyptus urophilla) aged 10.3 months old. Eighty sample evaluations were carried out considering the following severity levels: control (no shells), low infestation (N1), intermediate infestation (N2), and high infestation (N3), for which leaf spectral reflectances were obtained using a spectroradiometer. The spectral range acquired by the equipment was 350 to 2500 nm. After obtaining the wavelengths, they were grouped into representative interval means in 28 bands. Data were submitted to the following ML algorithms: artificial neural networks (ANN), REPTree (DT) and J48 decision trees, random forest (RF), support vector machine (SVM), and conventional logistic regression (LR) analysis. Two input configurations were tested: using only the wavelengths (ALL) and using the spectral bands (SB) to classify the attack levels. The output variable was the severity of G. brimblecombei attack. There were differences in the hyperspectral behavior of the leaves for the different attack levels. The highest attack level shows the greatest distinction and the highest reflectance values. LR and SVM show better accuracy in classifying the severity levels of G. brimblecombei attack. For the correct classification percentage, the RL and SVM algorithms performed better, both with accuracy above 90%. Both algorithms achieved F-score values close to 0.90 and above 0.8 for Kappa. The entire spectral range guaranteed the best accuracy for both algorithms. [ABSTRACT FROM AUTHOR]

The psyllid Aphalara itadori Shinji (Hemiptera: Psyllidae) is a biocontrol agent against invasive knotweed species (Polygonaceae) in Europe and North America. Despite an extensive release program, successful establishment of the agent has never been confirmed. The slow establishment of A. itadori in its introduced range appears to be predominantly the result of nymphal mortality, either through desiccation, predation, or the adaptation of captive populations to low‐stress environments. In 2016, CABI UK collected a new line of psyllids from Murakami, Niigata Prefecture, in Japan, where it was observed causing severe leaf‐roll galling on one of the many varieties of native knotweeds. The induction of leaf‐roll galls by Murakami psyllids on invasive Bohemian knotweed, Reynoutria × bohemica, has the potential to alleviate some or all of the observed nymphal mortality factors. We conducted a series of growth chamber experiments to explore the psyllid behaviors that initiate leaf‐roll galls, and the ways in which the galls might benefit the psyllids and inhibit invasive knotweed. Reynoutria × bohemica exposed to A. itadori for 4 weeks suffered reduced stem elongation and leaf area compared to control plants. Artificial leaf‐roll galls were consistently utilized by developing A. itadori nymphs, and contributed to their survival. Leaf‐roll galling in R. × bohemica was predominantly initiated by early instar nymphs of A. itadori, and only occurred when leaves were attacked at a very early stage in their development. Our results can inform the knotweed biocontrol program in several key ways. Releases of A. itadori should be timed so that developing nymphs have access to newly emerging leaves. Monitoring efforts at release sites should focus on the growing tips of R. × bohemica, where the highly mobile nymphs appear to migrate. Finally, our results provide motivation to seek additional lines of A. itadori that may affect other invasive knotweed species in similar ways. [ABSTRACT FROM AUTHOR]

In a forest of Nothofagus pumilio (lenga) in northern Chubut, we found a stand affected by Notophorina sp. (Hemiptera, Psyllidae) with outstanding foliar symptoms. We assumed that it is about a peak of abundance, which is the first record in Argentinean Patagonia. Our aim was to characterize the stand and the health condition of affected trees related to the peak abundance of Notophorina sp. In a stand located at 42°41'36.06" S - 71°44'42.26" W, in the Parque Nacional Los Alerces (Chubut, Argentina), two samplings were carried out in an eighteen day period (T1, T2) during the summer (January and February) of 2020. A health survey was performed and Notophorina sp. abundance was evaluated. Thirty percent of the trees showed defoliation in T1 and this value increased to 50% in T2. The symptoms were chlorosis, necrosis, leaves curling and partial or total defoliation. At T2, the previously affected trees had smaller leaves (1.80±0.38 cm²) than those recently affected (3.79±0.38 cm²), while the leaves of the healthy trees were the largest (6.99±0.38 cm²). The specific leaf area was similar for trees with old and recent infestation (123.3±20.34 cm²/g vs. 159.27±20.34 cm²/g) and significantly higher in healthy trees (289.15±20.34 cm²/g). The population density decreased drastically between both samplings (87%). This study contributes to the bioecological background of Notophorina sp. in the Patagonian Andean region and assesses the effect on its hosts. [ABSTRACT FROM AUTHOR]

We studied the population dynamics of the olive psyllid Euphyllura olivina Costa, 1857 in a semi-arid region (Djelfa, central Algeria) during a year, from December 2017 to November 2018. The visual control approach and the striking method were used to monitor the different stages of this pest. The species had two generations per year: a spring generation from March to June and a fall generation from September to November. The first generation of eggs is laid in March and continues through May. The second generation begins in late August and early September and continues through November. The statistical study of the impact of the researched climatic factors (minimum, maximum, and average temperatures; precipitation and frost) on the various stages differs from one stage to the next. [ABSTRACT FROM AUTHOR]

Cacopsylla pyricola (Förster) (Hemiptera: Psyllidae) is the most expensive and challenging insect pest of commercial pear trees in the Pacific Northwest. Integrated pest management (IPM) programs are working toward relying more heavily on natural enemies to reduce insecticide use. Trechnites insidiosus (Crawford) (Hymenoptera: Encyrtidae) is the main parasitoid of C. pyricola , but little is known about its biology in the region. Developing sampling tools is important for the deployment of IPM programs, including monitoring of natural enemies. In this study, we examined 2 conventional monitoring methods: beat trays and yellow sticky cards, in addition to screened sticky cards and 3D-printed cylinder traps. Additionally, we tested an overwintering trap for the collection of parasitized C. pyricola. The trapping methods were tested in orchards in Oregon and Washington. Unscreened cards caught the most T. insidiosus and C. pyricola , followed by screened cards, cylinder traps, and then beat trays. Beat trays sometimes failed to catch any T. insidiosus , even when it was found in abundance via other methods. Screened cards and cylinder traps reduced bycatch and increased ease of identifying T. insidiosus. Specimens from the cylinder traps were also more suitable for use in molecular analysis. The overwintering traps were effective at capturing parasitized C. pyricola , but were highly variable year to year. The ideal trapping method will vary based on research needs (e.g. DNA preservation, reducing bycatch, catching higher numbers), but both screened sticky cards and cylinder traps were viable methods for monitoring T. insidiosus and its host. [ABSTRACT FROM AUTHOR]

Most sap-feeding insects maintain obligate relationships with endosymbiotic bacteria that provide their hosts with essential nutrients. However, knowledge about the dynamics of endosymbiont titers across seasons in natural host populations is scarce. Here, we used quantitative PCR to investigate the seasonal dynamics of the dual endosymbionts "Candidatus Carsonella ruddii" and "Ca. Psyllophila symbiotica" in a natural population of the pear psyllid Cacopsylla pyricola (Hemiptera: Psylloidea: Psyllidae). Psyllid individuals were collected across an entire year, covering both summer and overwintering generations. Immatures harboured the highest titers of both endosymbionts, while the lowest endosymbiont density was observed in males. The density of Carsonella remained high and relatively stable across the vegetative period of the pear trees, but significantly dropped during the non-vegetative period, overlapping with C. pyricola's reproductive diapause. In contrast, the titer of Psyllophila was consistently higher than Carsonella's and exhibited fluctuations throughout the sampling year, which might be related to host age. Despite a tightly integrated metabolic complementarity between Carsonella and Psyllophila, our findings highlight differences in their density dynamics throughout the year, that might be linked to their metabolic roles at different life stages of the host. [ABSTRACT FROM AUTHOR]

Efficient and accurate detection and providing early warning for citrus psyllids is crucial as they are the primary vector of citrus huanglongbing. In this study, we created a dataset comprising images of citrus psyllids in natural environments and proposed a lightweight detection model based on the spatial channel interaction. First, the YOLO-SCL model was based on the YOLOv5s architecture, which uses an efficient channel attention module to perform local channel attention on the inputs in the recursive gated convolutional modules to achieve a combination of global spatial and local channel interactions, improving the model's ability to express the features of the critical regions of small targets. Second, the lightweight design of the 21st layer C3 module in the neck network of the YOLO-SCL model and the small target feature information were retained to the maximum extent by deleting the two convolutional layers, whereas the number of parameters was reduced to improve the detection accuracy of the model. Third, with the detection accuracy of the YOLO-SCL model as the objective function, the black widow optimization algorithm was used to optimize the hyperparameters of the YOLO-SCL model, and the iterative mechanism of swarm intelligence was used to further improve the model performance. The experimental results showed that the YOLO-SCL model achieved a mAP@0.5 of 97.07% for citrus psyllids, which was 1.18% higher than that achieved using conventional YOLOv5s model. Meanwhile, the number of parameters and computation amount of the YOLO-SCL model are 6.92 M and 15.5 GFlops, respectively, which are 14.25% and 2.52% lower than those of the conventional YOLOv5s model. In addition, after using the black widow optimization algorithm to optimize the hyperparameters, the mAP@0.5 of the YOLO-SCL model for citrus psyllid improved to 97.18%, making it more suitable for the natural environments in which citrus psyllids are to be detected. The experimental results showed that the YOLO-SCL model has good detection accuracy for citrus psyllids, and the model was ported to the Jetson AGX Xavier edge computing platform, with an average processing time of 38.8 ms for a single-frame image and a power consumption of 16.85 W. This study provides a new technological solution for the safety of citrus production. [ABSTRACT FROM AUTHOR]

Objectives: DNA Barcoding has proven to be a reliable method for rapid insect identification. The success of this method is based on the amplification of a specific region, the 'Folmer' barcode region at the 5´ start of the cytochrome c oxidase 1 gene (cox1), with universal primers. Previous studies showed failures of standard "universal" primers to amplify this region in psyllids. The aim of the study was the design of a new alternative more reliable primer combination for taxa of the superfamily Psylloidea and its comparison with the performance of the standard "universal" Folmer-primers. Results: A newly designed degenerate forward primer LCOP-F was developed following comparison of the sequence alignment of the priming site of "universal" primer LCO1490 and the standard insect forward primer LepF1. When combined with the "universal" reverse primer, HCO2198, this new primer pairing was able to generate barcode sequence for all 36 species in 20 genera across the five families of psyllids tested in this study, and these primers were found to be more universally reliable across psyllid taxa than other primer pairs tested. [ABSTRACT FROM AUTHOR]

Tactics that manipulate insect behavior are a component of many pest management strategies. Pheromone-based mating disruption is one such tactic widely used in agricultural systems, but few studies have assessed disrupting other mate communication mechanisms, such as acoustic signals. The most destructive pear pest in the Pacific Northwest USA, pear psylla (Cacopsylla pyricola) is believed to use acoustic signals to find mates, making it a candidate for this type of disruption. This species has two adult morphs, overwintering adults (winterforms) that emerge in the spring and subsequent generations (summerforms). Our study characterized the mating signals for both sexes and morphs of pear psylla, and assessed whether temperature and previous exposure to adult conspecifics altered signals and likelihood of signaling. While there are descriptions for acoustic signals of other psyllid species, this study provides the first evidence that C. pyricola communicates acoustically. The two sexes communicate via duetting; males signal to attract a female and the female signals back if she is receptive for mating. We showed that both morphotypes' male signals contain a group of chirps followed by a trill, while females respond with chirps. Male signal trills differed significantly in frequency (Hz) between winterform and summerform psylla. The signal frequency among morphs also had a positive linear relationship with temperature, suggesting that dissimilarity in signals among morphs had some relationship to temperature. Males were more likely to signal when they had previous exposure to females compared to males without exposure to females. Our results provide new information on how pear psylla communicate acoustically for mating, advancing the potential to develop mating disruption strategies for integrated pest management (IPM). [ABSTRACT FROM AUTHOR]

The pear pest, Cacopsylla jukyungi (Hemiptera: Psyllidae), is the most damaging insect to commercial pears in South Korea. An assessment of the population genetic characteristics of the species will raise the potential of effective control. In the present study, we developed eight microsatellite markers specific to C. jukyungi and genotyped 132 individuals collected from 11 localities throughout South Korea. Populations showed lower observed heterozygosity than expected heterozygosity and slightly or highly positive values of inbreeding coefficients, suggesting that C. jukyungi is subjected to inbreeding. A strong dependence on commercial pear trees throughout the whole life cycle, even during overwintering, and a nationwide targeting of the overwintered adults are likely contributors to such heterozygosity deficiency. On the other hand, population analyses consistently indicated strong gene flow among populations, implying the presence of persistent factors that have facilitated this process. The nationwide expansion of pear orchards and the replacement with a popular new cultivar during the last 50 years, which may have accompanied the spread of C. jukyungi-bearing pear grafts and scions, are likely causes of such facilitated dispersal. Thus, a management strategy against unintended anthropogenic dispersal of the pear psyllid will be required for better control of C. jukyungi. [ABSTRACT FROM AUTHOR]

The increasing translocation of people and goods has led to the introduction of species outside their native range. Amongst these "alien" or "non-native" species, a wide range of introduced trees have established in the Mediterranean, with their health, growth and/or value being negatively affected by insect pests. Encyrtidae are well-known for their use as biological control agents of scale insects and psyllids, with the latter groups including non-native pests of economic significance for introduced ornamental plants. Surveys in Greece and Cyprus unveil a total of 11 encyrtid wasps out of which three represent new records for Greece, i.e., Coccidoxenoides perminutus Girault, 1915, Cryptanusia aureiscutellum (Girault), and Isodromus ustianae Hoffer & Trjapitzin, 1967, and three for Cyprus, i.e., Isodromus luppovae Trjapitzin, Leptomastix gigantum Japoshvili, and Psyllaephagus macrohomotoma Singh & Agarwal, 1993. Psyllaephagus schauffi sp. nov. was collected from Greece and Cyprus, being described and illustrated as a new species to science. Additionally, Cacopsylla pulchella (Löw) is recorded as a new host for Prionomitus mitratus (Dalman), with the presence of the latter species in Greece being confirmed. The number of known encyrtid wasps for Greece and Cyprus are raised to 90 and 29, respectively, whereas further studies are necessary to assess the biodiversity of Encyrtidae distributed in both countries as well as the impacts of non-native species. [ABSTRACT FROM AUTHOR]

The carrot psyllid, Bactericera trigonica, is a vector of 'Candidatus Liberibacter solanacearum' which infects carrots and many of solanaceous plants. The psyllid was first reported in Spain, then it was rapidly spreading throughout the Mediterranean countries, where it causes considerable damages to carrot crops. To minimize the spread of psyllid species as well as the associated fastidious bacteria, field inspections have been carried out in order to seek for a natural enemies of B. trigonica. Field surveys revealed the presence of a new eulophid parasitoid for the first time in Tunisia attacking larvae of B. trigonica, the main responsible for the significant losses in carrot fields. In order to study the parasitism rate of this parasitoid, a weekly sampling of carrot plants carrying the psyllids and its parasitoids was performed in carrot fields. The parasitism rate and the preferential stage for this parasitoid were also determined under laboratory conditions. The result shows Tamarixia pronomus, preferred late (4th and 5th) instar larvae to early (2nd and 3rd) instar larvae of B. trigonica. There, the parasitism average of late instars was estimated to average 80% and approached 100%. It should be noted that parasitism rates varied by season, with the spring showing the highest averages. Further efforts are warranted to enhance the biological control of B. trigonica and thereby reduce psyllid populations and the spread of 'Candidatus Liberibacter solanacearum'. [ABSTRACT FROM AUTHOR]

Simple Summary: Candidatus Liberibacter asiaticus (CLas) is a putative causal agent of Huanglongbing, a serious citrus pathogen. Diaphorina citri Kuwayama (Hemiptera: Psyllidae) is the primary vector of CLas. Florida only has CLas, and the only vector of CLas in Florida is D. citri. We explored patterns in the proportion of psyllids carrying CLas by analyzing psyllids collected from seven field sites from 2008 through February 2012. There was an upsurge in prevalence in the fall and, in some groves, a second peak in the spring. We also found that females were more common in the first and last months of the year. D. citri has different abdominal colors that we grouped into blue/green and gray/brown. Gray/brown psyllids had a higher CLas prevalence than blue/green individuals. We suggest several explanations for these patterns, but the two most likely involve a hypothesized CLas gradient in the first few millimeters of new growth and differences in immune response related to sex and color. In application, the results confirm that psyllid management is always necessary because psyllids carry CLas year-round. The seven study sites had seven levels of management, from abandoned to intensively managed. In general, more aggressively managed groves had fewer psyllids with CLas. A well-managed organic grove was an exception, having low CLas prevalence but abundant psyllids. It is possible that the low CLas prevalence at this grove was due to management techniques or that this area was infected more recently. Candidatus Liberibacter asiaticus (CLas) is one of the putative causal agents of huanglongbing, which is a serious disease in citrus production. The pathogen is transmitted by Diaphorina citri Kuwayama (Hemiptera: Psyllidae). As an observational study, six groves in central Florida and one grove at the southern tip of Florida were sampled monthly from January 2008 through February 2012 (50 months). The collected psyllids were sorted by sex and abdominal color. Disease prevalence in adults peaked in November, with a minor peak in February. Gray/brown females had the highest prevalence, and blue/green individuals of either sex had the lowest prevalence. CLas prevalence in blue/green females was highly correlated with the prevalence in other sexes and colors. Thus, the underlying causes for seasonal fluctuations in prevalence operated in a similar fashion for all psyllids. The pattern was caused by larger nymphs displacing smaller ones from the optimal feeding sites and immunological robustness in different sex–color morphotypes. Alternative hypotheses were also considered. Improving our understanding of biological interactions and how to sample them will improve management decisions. We agree with other authors that psyllid management is critical year-round. [ABSTRACT FROM AUTHOR]

The Old-World Psyllid, Heterotrioza chenopodii (Hemiptera, Psylloidea, Triozidae) was found infesting quinoa, Chenopodium quinoa (Amaranthaceae) crop. The psyllids were identified using taxonomic traits and further confirmation with mitochondrial marker based molecular approach. The information on damage and its life stages is reported along with the phylogenetic information of the species. The identity analysis in NCBI indicated that the MT-COI sequences of H. chenopodii were 96 per cent identical to the previously deposited sequences with NCBI and five submissions with accession numbers were made viz., OP735496, OP740826, OP740828, OP740829 and OP740830. The phylogenetic tree represented the similarities in the analyzed sequences Indian populations are found to be merged in between the other similar global populations. [ABSTRACT FROM AUTHOR]

Trioza tabebuiae Burckhardt & Santana, 2001 is an important pest of some ornamental plants species of the family Bignonaceae in Brazil. This psyllid causes serious damages in leaves of Handroanthus Mattos, 1970 tress curving its margins which reduce the photosynthetic area when high infestations. In Argentina, Handroanthus heptaphyllus (Vell.) Mattos, 1970 is a relevant tree for its wood and for ornamental use. Here, we report for the first time the presence of the psyllid T. tabebuiae associated with the bignonaceous tree H. heptaphyllus in Argentina. Moreover, the damage produced by T. tabebuiae in leaves of the Pink Trumpet trees was observed.

The bacterial pathogen Candidatus Liberibacter asiaticus (CLas) is the causal agent of citrus greening disease. This unusual plant pathogenic bacterium also infects its psyllid host, the Asian citrus psyllid (ACP). To investigate gene expression profiles with a focus on genes involved in infection and circulation within the psyllid host of CLas, RNA-seq libraries were constructed from CLas-infected and CLas-free ACP representing the five different developmental stages, namely, nymphal instars 1-2, 3, and 4-5, and teneral and mature adults. The Gbp paired-end reads (296) representing the transcriptional landscape of ACP across all life stages and the official gene set (OGSv3) were annotated based on the chromosomal-length v3 reference genome and used for de novo transcript discovery resulting in 25,410 genes with 124,177 isoforms. Differential expression analysis across all ACP developmental stages revealed instar-specific responses to CLas infection, with greater overall responses by nymphal instars, compared to mature adults. More genes were over-or under-expressed in the 4-5th nymphal instars and young (teneral) adults than in instars 1-3, or mature adults, indicating that late immature instars and young maturing adults were highly responsive to CLas infection. Genes identified with potential for direct or indirect involvement in the ACP-CLas circulative, propagative transmission pathway were predominantly responsive during early invasion and infection processes and included canonical cytoskeletal remodeling and endo-exocytosis pathway genes. Genes with predicted functions in defense, development, and immunity exhibited the greatest responsiveness to CLas infection. These results shed new light on ACP-CLas interactions essential for pathogenesis of the psyllid host, some that share striking similarities with effector protein-animal host mechanisms reported for other culturable and/or fastidious bacterial- or viral-host pathosystems. [ABSTRACT FROM AUTHOR]

Psyllid yellows, vein-greening (VG), and zebra chip (ZC) diseases, which are primarily transmitted by potato psyllid (PoP) carrying Candidatus Liberibacter solanacearum (CLso), have caused significant losses in solanaceous crop production worldwide. Pathogens interact with their vectors at the organic and cellular levels, while the potential changes that may occur at the biochemical level are less well reported. In this study, the impact of CLso on the metabolism of PoP and the identification of biomarkers from infected psyllids were examined. Using ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) analysis, metabolomic changes in CLso-infected psyllids were compared to uninfected ones. A total of 34 metabolites were identified as potential biomarkers of CLso infection, which were primarily related to amino acid, carbohydrate, and lipid metabolism. The significant increase in glycerophospholipids is thought to be associated with CLso evading the insect vector's immune defense. Matrix-assisted Laser Desorption Ionization Mass Spectrometry Imaging (MALDI-MSI) was used to map the spatial distribution of these biomarkers, revealing that 15-keto-Prostaglandin E2 and alpha-D-Glucose were highly expressed in the abdomen of uninfected psyllids but down-regulated in infected psyllids. It is speculated that this down-regulation may be due to CLso evading surveillance by immune suppression in the PoP midgut. Overall, valuable biochemical information was provided, a theoretical basis for a better understanding of psyllid-pathogen interactions was offered, and the findings may aid in breaking the transmission cycle of these diseases. [ABSTRACT FROM AUTHOR]

Background: The Australian citrus industry remains one of the few in the world to be unaffected by the African and the Asian citrus psyllids, Trioza erytreae Del Guercio and Diaphorina citri Kuwayama, respectively, and the diseases their vectored bacteria can cause. Surveillance, early detection, and strict quarantine measures are therefore fundamental to safeguard Australian citrus. However, long-term targeted surveillance for exotic citrus pests can be a time-consuming and expensive activity, often relying on manually screening large numbers of trap samples and morphological identification of specimens, which requires a high level of taxonomic knowledge. Methods: Here we evaluated the use of non-destructive insect metabarcoding for exotic pest surveillance in citrus orchards. We conducted an 11-week field trial, between the months of December and February, at a horticultural research farm (SuniTAFE Smart Farm) in the Northwest of Victoria, Australia, and processed more than 250 samples collected from three types of invertebrate traps across four sites. Results: The whole-community metabarcoding data enabled comparisons between different trapping methods, demonstrated the spatial variation of insect diversity across the same orchard, and highlighted how comprehensive assessment of insect biodiversity requires use of multiple complimentary trapping methods. In addition to revealing the diversity of native psyllid species in citrus orchards, the non-targeted metabarcoding approach identified a diversity of other pest and beneficial insects and arachnids within the trap bycatch, and recorded the presence of the triozid Casuarinicola cf warrigalensis for the first time in Victoria. Ultimately, this work highlights how a non-targeted surveillance approach for insect monitoring coupled with non-destructive DNA metabarcoding can provide accurate and high-throughput species identification for biosecurity and biodiversity monitoring. [ABSTRACT FROM AUTHOR]

As significant threats to global citrus production, Diaphorina citri (Kuwayama; Hemiptera: Psyllidae) and Trioza erytreae (Del Guercio; Hemiptera: Triozidae) have caused considerable losses to citrus trees globally. Diaphorina citri vectors "Candidatus Liberibacter asiaticus" and "Ca. L. americanus", whereas T. erytreae transmits "Ca. L. africanus" and "Ca. L. asiaticus", the pathogens responsible for citrus greening disease or Huanglongbing (HLB). Though HLB is a destructive disease of citrus wherever it occurs, information on the occurrence and geographical distribution of its vectors in Africa is limited. In recent surveys to determine if HLB vectors are present in Ghana, we observed eggs, nymphs, and adults of insects suspected to be D. citri and T. erytreae. Using morphological traits and DNA analyses, the identity of the suspected insects was confirmed to be D. citri and T. erytreae. Individuals of D. citri and T. erytreae were examined using qPCR for CLaf, CLam, and CLas, but none of them tested positive for any of the Liberibacter species. Herein we report, for the first time, the presence of D. citri and T. erytreae in Ghana (West Africa). We discuss the implications of this new threat to the citrus industry to formulate appropriate management strategies. [ABSTRACT FROM AUTHOR]

Diaphorina citri Kuwayama, also known as the Asian citrus psyllid (ACP), can vector the bacterium Candidatus Liberibacter asiaticus (CLas), agent of Huanglongbing (HLB): an incurable disease affecting citrus trees worldwide. In citrus growing regions where ACP and HLB are absent, such as Australia, the risk of an incursion and consequent economic damage to citrus industries make this psyllid one of the top-priority pests. Due to ACP's small dimensions and the generally poorly studied native psylloid fauna worldwide, morphological identification of this insect to distinguish it from harmless species is challenging, especially in the field, and with immature, partial or damaged specimens. To allow rapid and efficient detection of ACP in the field, we designed and optimised a new Loop-mediated isothermal amplification (LAMP) assay for the detection of D. citri based on the mitochondrial 16S locus. The optimised ACP 16S LAMP assay produced amplification from D. citri samples within 13.3 ± 3.6 min, with an anneal derivative of ~ 78.5 °C. A synthetic gBlock gene fragment was also developed to be used as positive control for the new LAMP assay with a different anneal derivative of ~ 83 °C. An existing commercially available LAMP assay for detection of the bacterium CLas was also tested in this study on ACP DNA. The ACP 16S LAMP assay we developed and tested here provides a valuable new in-field compatible tool that can allow early detections of ACP, enabling a quick biosecurity response, and could potentially be adopted by a wide range of users, from farmers to agronomists and from researchers to industry. [ABSTRACT FROM AUTHOR]

Boxwood (Buxus sempervirens) is a host for several mite and insect pests, but the species of plant-parasitic psyllid Spanioneura fonscolombii has been observed in Romania for the first time in 2017. Subsequent research has shown that the species is much more spread, our data confirming its presence in western, eastern, and southern Romania. This is also the most south-eastern record of the species in Europe. [ABSTRACT FROM AUTHOR]

Hemiptera is the largest order of non‐holometabolous insects. Recent phylogenetic studies have contributed greatly to our understanding of the phylogeny of the group. However, parts of the hemipteran tree remain unclear. In this study, we have sequenced transcriptomes from five sternorrhynchan species, four exemplars from Aphididae, and one from Monophlebidae. The addition of published transcriptome data produced alignments of >105 000 amino acids from 224 hemipteran taxa in 30 superfamilies covering all suborder and infraorder clades. The data confirmed the Sternorrhyncha superfamily relationship of Aleyrodoidea + (Psylloidea + [Coccoidea + Aphidoidea]). In addition, phylogenomic analyses supported a basal split of Sternorrhyncha and the remaining hemipteran lineages. The Fulgoromorpha formed a sister clade to Cicadomorpha, with strong support. Therefore, our results supported the monophyly of Auchenorrhyncha. The Coleorrhyncha was robustly resolved as a sister group of Auchenorrhyncha, contrary to the concept of the Heteropterodea. Within Heteroptera, the Enicocephalomorpha, Dipsocoromorpha, and Gerromorpha were resolved as the earliest branching groups, while the Nepomorpha, Leptopodomorpha, Cimicomorpha, and Pentatomomorpha were the successive sister groups to the remaining clades in the series. The Cimicomorpha and Pentatomomorpha were sister groups that occupied the most apical branches of the heteropteran tree. Although some phylogenetic estimates yielded conflicting hypotheses for superfamily relationships of Cicadomorpha, Four‐cluster Likelihood Mapping (FcLM) analyses revealed a greater phylogenetic signal for the relationship of Membracoidea + (Cicadoidea + Cercopoidea). Highlights: Sternorrhyncha was sister to all other hemipteran lineages.The monophyly of Auchenorrhyncha was strongly supported.The Coleorrhyncha was robustly resolved as a sister group of Auchenorrhyncha.The Aleyrodoidea was sister to a clade (Psylloidea + [Coccoidea + Aphidoidea]). [ABSTRACT FROM AUTHOR]

'Candidatus Liberibacter solanacearum' (Lso) is a bacterial pathogen infecting several crops and causing damaging diseases. Several Lso haplotypes have been identified. Among the seven haplotypes present in North America, LsoA and LsoB are transmitted by the potato psyllid, Bactericera cockerelli (Šulc), in a circulative and persistent manner. The gut, which is the first organ pathogen encounters, could be a barrier for Lso transmission. However, the molecular interactions between Lso and the psyllid vector at the gut interface remain largely unknown. In this study, we investigated the global transcriptional responses of the adult psyllid gut upon infection with two Lso haplotypes (LsoA and LsoB) using Illumina sequencing. The results showed that each haplotype triggers a unique transcriptional response, with most of the distinct genes elicited by the highly virulent LsoB. The differentially expressed genes were mainly associated with digestion and metabolism, stress response, immunity, detoxification as well as cell proliferation and epithelium renewal. Importantly, distinct immune pathways were triggered by LsoA and LsoB in the gut of the potato psyllid. The information in this study will provide an understanding of the molecular basis of the interactions between the potato psyllid gut and Lso, which may lead to the discovery of novel molecular targets for the control of these pathogens. [ABSTRACT FROM AUTHOR]

Diaphorina citri, a vector of citrus huanglongbing (HLB) disease, frequently leads to HLB outbreaks and reduces Rutaceae crop production. Recent studies have investigated the effects of RNA interference (RNAi) targeting the Vitellogenin (Vg4) and Vitellogenin receptor (VgR) genes, which are involved in egg formation in this pest, providing a theoretical foundation for developing new strategies to manage D. citri populations. This study presents RNAi methods for Vg4 and VgR gene expression interference and reveals that dsVgR is more effective than dsVg4 against D. citri. We demonstrated that dsVg4 and dsVgR persisted for 3–6 days in Murraya odorifera shoots when delivered via the in-plant system (IPS) and effectively interfered with Vg4 and VgR gene expression. Following Vg4 and VgR gene expression interference, egg length and width in the interference group were significantly smaller than those in the negative control group during the 10–30-day development stages. Additionally, the proportion of mature ovarian eggs in the interference group was significantly lower than that in the negative control group at the 10, 15, 20, 25, and 30-day developmental stages. DsVgR notably suppresses oviposition in D. citri, with fecundity decreasing by 60–70%. These results provide a theoretical basis for controlling D. citri using RNAi to mitigate the spread of HLB disease. [ABSTRACT FROM AUTHOR]

The bacterial microbiome of psyllids has been studied for decades, with a strong focus on the primary and secondary endosymbionts capable of providing essential amino acids for the insects' diet and therefore playing a key role in the insects' ability to radiate on novel plant hosts. Here, we combine metabarcoding analysis of the bacterial communities hosted by psyllids with a multi-gene phylogenetic analysis of the insect hosts to determine what factors influence the bacterial diversity of the psyllids' microbiomes, especially in the context of the dispersal and evolutionary radiation of these insects in Aotearoa New Zealand. Using multi-gene phylogenetics with COI, 18S and EF-1α sequences from 102 psyllid species, we confirmed for the first time monophyly for all the six genera of native/endemic Aotearoa New Zealand psyllids, with indications that they derive from at least six dispersal events to the country. This also revealed that, after its ancestral arrival, the genus Powellia has radiated onto a larger and more diverse range of plants than either Psylla or Ctenarytaina, which is uncommon amongst monophyletic psyllids globally. DNA metabarcoding of the bacterial 16S gene here represents the largest dataset analysed to date from psyllids, including 246 individuals from 73 species. This provides novel evidence that bacterial diversity across psyllid species is strongly associated with psyllid phylogenetic structure, and to a lesser degree to their host plant association and geographic distribution. Furthermore, while the strongest co-phylogenetic signals were derived from the primary and secondary symbionts, a signal of phylosymbiosis was still retained among the remaining taxa of the bacterial microbiome, suggesting potential vertical transmission of bacterial lineages previously unknown to have symbiotic roles. [ABSTRACT FROM AUTHOR]

Simple Summary: Cacopsylla, the most species-rich genus of Psyllidae, has around 500 known species worldwide. These insects are known for being host-specific, and some of them are regarded as important pests. Here, we described a new species, Cacopsylla fuscicella sp. nov., which develops on loquats. In addition, we sequenced its mitochondrial genome and used these data to construct a phylogenetic tree of Psyllidae, while also calculating the interspecific genetic distances. Using integrative taxonomy methods, we confirmed that the new species, Cacopsylla fuscicella sp. nov., should be grouped within genus Cacopsylla. Psylloidea, commonly known as jumping plant-lice, have a phloem-sucking habit and strong specificity to their host plants. Within the Psyllidae family, the genus Cacopsylla Ossiannilsson, 1970 stands out as being the most diverse, with three species feeding on the genus Eriobotrya Lindl. In this study, a new psyllid species, Cacopsylla fuscicella sp. nov., was described from China. It is a pest of Eriobotrya japonica (Thunb.) Lindl. and has been cultivated as a commercial fruit tree for years. Illustrations of habitus, morphological structures, and its damage to loquat were also provided. The complete mitochondrial genome of C. fuscicella sp. nov. was sequenced and annotated. The phylogenetic tree inferred from the maximum likelihood analyses confirmed C. fuscicella sp. nov. as a member of the genus Cacopsylla. Genetic distances were generated to assess comparative genetic distances within Psyllinae. [ABSTRACT FROM AUTHOR]

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The common pistachio psylla, Agonoscena pistaciae, is a major pest of the pistachio trees, which is supposed to be consisted of many allopatric populations. Since psyllids, including A. pistaciae, have close associations with various obligate mutualists and facultative symbionts, the study was conducted to determine the diversity of bacterial endosymbionts associated with four psyllid populations viz., Feizabad, Neyshabour, Kerman and Khash. Psyllids were evaluated for their gut endosymbionts through PCR amplifications with their specific primers. The sequences were subjected to a BLAST search to find most similar sequences in GenBank. Our findings disclosed the presence of 'Candidatus Carsonella ruddii' (primary endosymbiont), Wolbachia, and Hamiltonella (secondary endosymbionts). There were no infection of Serratia in the pistachio psyllid populations. 'Ca. Carsonella ruddii' showed a 100% infection frequency in populations and Wolbachia, Arsenophonus and Hamiltonella indicated 50, 15 and 20% infection frequencies, respectively. The rate of infection with Wolbachia, Arsenophonus and Hamiltonella ranged from 40 to 70%, 0 to 40% and 10 to 30%, respectively. The current study furnished an insight into endosymbiont variation in the pistachio psyllid populations; nonetheless, more investigations are required to assess their probable impacts on the fitness of their psyllid host. [ABSTRACT FROM AUTHOR]