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Symptoms of leaf yellowing, reddening, witches' broom and declining were observed in peach, apricot, and plum orchards from two states and a union territory [Himachal Pradesh (H.P.), Uttarakhand and Jammu & Kashmir (J&K)] of India during 2019–2021. Association of three groups (16SrI, 16SrII,16SrV) of phytoplasma were confirmed in symptomatic peach, plum and apricot samples by amplifying DNA using 16S rRNA and multiple non-ribosomal primers (secA, secY, tuf). Pair wise sequence comparison, phylogenetic analysis and virtual RFLP analysis using multiple non-ribosomal gene sequences confirmed the presence of 'Candidatus Phytoplasma asteris' (16SrI-B), 'Ca. Phytoplasma australasia' (16SrII-D), elm yellows (new subgroup variant of 16SrV) and 'Ca. Phytoplasma ziziphi' (16SrV-B) related strains in peach, plum and apricot trees. Besides, other suspected symptomatic plant hosts and weeds in and around stone fruit orchards were also identified positive with phytoplasma strains belonging to 16SrI-B and 16Sr II-D subgroups by amplifying 16SrRNA and secA genes and sequence analysis. Association of similar strains of phytoplasma was identified in leafhopper species, Hishimonus phycitis from J&K and Empoasca sp. from Uttarakhand by utilizing the same set of primer pairs and 16S rRNA and secA gene sequence comparison. The presence of 'Ca. P. asteris' (16SrI-B) and 'Ca. P. australasia' (16SrII-D) related strains detected in peach are new host records from India and the association of elm yellows (a variant of 16SrV subgroup) related strain in plum is the first report in the world. [ABSTRACT FROM AUTHOR]

Abstract The first two complete mitogenomes of the leafhopper genus Cladolidia (C. biungulata and C. robusta) were sequenced and annotated to further explore the phylogeny of Cladolidia. Both the newly sequenced mitogenomes have a typical circular structure, with lengths of 15,247 and 15,376 bp and A + T contents of 78.2% and 78%, respectively. We identified a highly conserved genome organization in the two Cladolidia spp. through comparative analysis that included the following assessments: genome content, gene order, nucleotide composition, codon usage, amino acid composition, and tRNA secondary structure. Moreover, we detected the base heterogeneity of Cicadellidae mitogenomic data and constructed phylogenetic trees using the nucleotide alignments of 12 subfamilies of 58 leafhopper species. We noted a weak heterogeneity in the base composition among the Cicadellidae mitogenomes. Phylogenetic analyses showed that the monophyly of each subfamily was generally well supported in the family Cicadellidae; the main topology was as follows: (Deltocephalinae + (Treehoppers + ((Megophthalminae + (Macropsinae + (Hylicinae + (Coelidiinae +Iassinae)) + (Idiocerinae + (Cicadellinae + (Typhlocybinae + (Mileewinae + (Evacanthinae +Ledrinae)))))))))). Within Coelidiinae, phylogenetic analyses revealed that C. biungulata and C. robusta belong to Coelidiinae and the monophyly of Cladolidia is well supported. In addition, on the basis of complete mitogenome phylogenetic analysis and the comparison of morphological characteristics, we further confirm the genus Olidiana as a paraphyletic group, suggesting that the genus may need taxonomic revisions.

The leafhopper genus Empoascanara was established by Distant (1918). So far, 81 species of the genus Empoascanara have been reported, most of which are distributed in Afrotropical or Oriental or Australian regions. The leafhopper genus Kapsa was established by Dworakowska (1972) and mainly distributed in the Orient or Australia.Two new species of the leafhopper tribe Erythroneurini from Guizhou province, China, Empoascanara dichotomus sp. nov. and Kapsa sinuose sp. nov. are described and illustrated. Two keys to distinguish the Chinese species of the genus are given.

Maize streak virus disease, caused by the maize streak virus, has been identified as severe vector-borne disease in Africa. In most regions of the continent, the disease is generally uncontrolled, and in epidemic years, it contributes to massive yield losses and famine. We propose a Holling-type predation functional response to explore the disease transmission. We show the sensitivity indices of various embedded parameters in the basic reproduction number. To illustrate the dynamics of the disease of the maize–leafhopper interaction, we perform a numerical simulation, and the results are graphically displayed. Incorporating four control methods (infection control, predation control, removal of infected maize plants, and insecticide application) into the basic model yields an optimal control issue. We used the Incremental Cost-Effectiveness Ratio technique to evaluate the most cost-effective combination of the four controls. We notice that the most cost-effective strategy combines the simultaneous adoption of the four controls.

Phytoplasmas are plant pathogenic wall-less bacteria transmitted in a persistent propagative manner by hemipteran insects, mainly belonging to the suborder Auchenorrhyncha (Fulgoromorpha and Cicadomorpha). Flavescence dorée (FD) is a quarantine disease of grapevine, causing great damage to European viticulture and associated with phytoplasmas belonging to 16SrV-C (FD-C) and -D (FD-D) subgroups. FD-C and FD-D strains share similar pathogenicity, but mixed infections are rare in nature. To investigate the competition among FDp strains, specimens of the laboratory vector Euscelidius variegatus (Hemiptera: Cicadellidae) were forced to acquire both phytoplasma haplotypes upon feeding on FD-C- and FD-D-infected plants or after the injection of both strains. The pathogen colonization of insect bodies and heads was monitored with multiplex qPCR, and the efficiencies of phytoplasma transmission were estimated. Single infection, irrespective of strain type, was more frequent than expected, indicating that competition among FD strains occurs. Hypotheses of competition for resources and/or host active sites or the direct antibiosis of one strain against the other are discussed, based on the genetic complexity of FDp populations and on the high genome variability of the FD-D strain. As FD management still mainly relies on insecticides against vectors, the characterization of FDp haplotypes and the description of their epidemiology also have practical implications.

Recilia dorsalis is a notorious rice pest that harbors numerous symbiotic microorganisms. However, the structure and dynamics of bacterial communities in various tissues of R. dorsalis throughout its life cycle remain unclear. In this study, we used high-throughput sequencing technology to analyze the bacterial communities in the digestive, excretory, and reproductive systems of R. dorsalis at different developmental stages. The results showed that the initial microbiota in R. dorsalis mostly originated from vertical transmission via the ovaries. After the second-instar nymphs, the diversity of bacterial communities in the salivary gland and Malpighian tubules gradually decreased, while the midgut remained stable. Principal coordinate analysis revealed that the structure of bacterial communities in R. dorsalis was primarily influenced by the developmental stage, with minimal variation in bacterial species among different tissues but significant variation in bacterial abundance. Tistrella was the most abundant bacterial genus in most developmental stages, followed by Pantoea. The core bacterial community in R. dorsalis continuously enriched throughout development and contributed primarily to food digestion and nutrient supply. Overall, our study enriches our knowledge of the bacterial community associated with R. dorsalis and provides clues for developing potential biological control technologies against this rice pest.

Nitrogen is a crucial element for the growth and development of insects, but herbivorous insects often suffer from nitrogen nutrition deficiencies in their diets. Some symbiotic microorganisms can provide insect hosts with nitrogen nutrition through nitrogen fixation. Extensive research has clearly demonstrated the process of nitrogen fixation by symbiotic microorganisms in termites, while evidence supporting the occurrence and significance of nitrogen fixation in the diets of the Hemiptera is less conclusive. In this study, we isolated a strain of R. electrica from the digestive tract of a leafhopper, R. dorsalis, and found that it had nitrogen-fixing capabilities. Fluorescence in situ hybridization results showed that it was located in the gut of the leafhopper. Genome sequencing revealed that R. electrica possessed all the genes required for nitrogen fixation. We further evaluated the growth rate of R. electrica in nitrogen-containing and nitrogen-free media and measured its nitrogenase activity through an acetylene reduction assay. The findings of these studies could shed light on how gut microbes contribute to our understanding of nitrogen fixation.

This study was conducted to evaluate whether conventional farming can be replaced by a lower chemical pollution farming system, integrated rice-duck farming in a suburban agricultural area in northern Zhejiang, Southeast China. We comprehensively assessed the impacts of integrated rice-duck farming on weeds and herbivorous insects along with their natural enemies during the rice-growing season. We found that the rice-duck system effectively controlled weeds within the paddy fields. Nevertheless, the abundance of herbivores, particularly planthoppers and leafhoppers was increased in the duck-roaming paddy fields compared to the control and conventional fields, indicating the inefficiency of the rice-duck system in the control of rice main herbivore pests. Rice-duck farming significantly reduced the abundance of predators, especially spiders and dragonflies, therefore an 'enemy-free space' was created for herbivores which might be responsible for the observed herbivore increase in the rice-duck fields. Despite the inefficiency of rice-duck farming in the control of rice main herbivore pests, the net income of the rice-duck treatment with an organic certification was 7.6 and 1.4 times higher compared to the conventional and control treatments, respectively. In the view of the favourable results obtained in this study, the integrated rice-duck farming system might be suggested as a high economic return organic farming method suitable for modern farmers. [ABSTRACT FROM AUTHOR]

The mango crop suffers a significant loss because of its infestation by mango leaf hoppers. Both nymphs and adults of mango hoppers cause severe damage to the mango plants at the flowering and fruiting stages. The damage is done mainly through the sucking of sap by the nymphs and adults of hoppers from the young soft leaves, shoots, and inflorescence, resulting in low crop yield and enormous economic loss to the farmers. The review aims at the seasonal incidence of mango leaf hoppers. [ABSTRACT FROM AUTHOR]

BACKGROUND: Since the last decade, Dalbulus maidis has become the primary pest in cornfields, particularly due to its ability to transmit plant pathogens. Dalbulus maidis is the main vector of the corn stunt spiroplasma and maize bushy stunt phytoplasma. However, there is little information available on this pest. Understanding its spatial dynamics may allow us to determine how its infestations begin and to identify its colonization patterns, dispersal, and the role of landscape structure on D. maidis dynamics. Thus, this study aimed to investigate within‐field spatial distribution and the factors associated with D. maidis abundance in five commercial fields. RESULTS: In all fields, higher infestations occurred at the boundaries of the central pivot, showing a clear edge‐biased distribution. Ranges varied from 100.4 to 611.8 m, and our models' overall fit indicated strong to moderate spatial dependency. Additionally, correlation analyses indicated a positive effect of air temperature on the population of D. maidis. Conversely, rainfall negatively affected D. maidis. CONCLUSION: This study provides essential guidance for improving D. maidis integrated pest management at regional and local scales. Based on its high dispersal ability, our study suggests the need for a legislative or regulatory method of control for D. maidis, especially in regions where corn has more than one growing season. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Melanization in the hemolymph of arthropods is a conserved defense strategy against infection by invading pathogens. Numerous plant viruses are persistently transmitted by insect vectors, and must overcome hemolymph melanization. Here, we determine that the plant rhabdovirus rice stripe mosaic virus (RSMV) has evolved to evade the antiviral melanization response in the hemolymph in leafhopepr vectors. After virions enter vector hemolymph cells, viral nucleoprotein N is initially synthesized and directly interacts with prophenoloxidase (PPO), a core component of the melanization pathway and this process strongly activates the expression of PPO. Furthermore, such interaction could effectively inhibit the proteolytic cleavage of the zymogen PPO to active phenoloxidase (PO), finally suppressing hemolymph melanization. The knockdown of PPO expression or treatment with the PO inhibitor also suppresses hemolymph melanization and causes viral excessive accumulation, finally causing a high insect mortality rate. Consistent with this function, microinjection of N into leafhopper vectors attenuates melanization and promotes viral infection. These findings demonstrate that RSMV N serves as the effector to attenuate hemolymph melanization and facilitate viral persistent propagation in its insect vector. Our findings provide the insights in the understanding of ongoing arms race of insect immunity defense and viral counter-defense. [ABSTRACT FROM AUTHOR]

Cotton leafhopper, Amrasca biguttula biguttula (Ishida) (Hemiptera: Cicadellidae) is a major sucking insect pest of cotton in India. Indiscriminate use of pesticides has led to the development of resistance to most of the recommended pesticide groups. Though there are multiple mechanisms and principles of insecticide resistance development in insects, the gut bacterial-mediated degradation of insecticides is relatively less explored. In the present study, the gut bacteria of field-collected, insecticide-resistant population of A. biguttula biguttula were compared with a laboratory-reared susceptible population. Among the five culturable gut bacteria from the imidacloprid-resistant population, only Enterococcus silesiacus CLHG1a exhibited growth in the agar medium amended with 50 and 100 ppm of imidacloprid. The imidacloprid degrading capacity of E. silesiacus CLHG1a was further confirmed by HPLC analysis. E. silesiacus and Bacillus amyloliquefaciens CLHG2 showed higher esterolytic activity (0.348 and 0.309 µmoles/min/mg respectively). The esterase zymogram on native PAGE revealed a single major band. This study provides clear evidence that the bacterium E. silesiacus isolated from the gut of A. biguttula biguttula has the ability to degrade imidacloprid and may have played a role in the detoxification of pesticides. [ABSTRACT FROM AUTHOR]

Maize streak virus (MSV) is a major threat to cereal production, hence food security in sub-Saharan Africa. The virus is spread mainly by insect vectors. The leafhoppers composition and distribution of potential MSV vectors were evaluated, and the performance of various control techniques against the vectors assessed in the major maize production areas of Cameroon. These techniques included the use of botanical extracts of Azadirachta indica A Juss. and Chenopodium ambrosoides L. Mosyakin and Clements, intercropping maize with cassava and soybean, and use of the synthetic insecticides Imidacloprid. The infection coefficient of maize streak disease and the abundance of leafhoppers were assessed in three agro-ecological zones of Cameroon (AEZs) including the Sudano-Sahelian zone (AEZ I), the Western highlands (AEZ III) and the humid forest with bimodal rainfall (AEZ V). Among 15 leafhoppers species recorded, 15 were recorded in AEZ I; 14 in AEZ III and 12 in AEZ V. The most abundant species in each AEZ was Afrosteles distans (Linnavuori) while the least abundant was Aconurella erebus (Distant). Intercropping maize with cassava and maize with soybean significantly reduced the infection coefficient of MSV in the different study zones. Also, phytochemical treatments significantly performed well with neem being the most efficient in the reduction of abundance compared to the other treatments. Thus, the use of the plant extracts and intercropping against leafhopper vectors of MSV effective. [ABSTRACT FROM AUTHOR]

The North American native prairie grass Panicum virgatum (switchgrass) is a primary bioenergy feedstock candidate. Its widespread distribution and genetic diversity enable the possibility of developing this perennial grass for high production in a variety of conditions, including on marginal lands. A critical concern in feedstock development and deployment is the risk of novel pathogen emergence. Here, we investigate the landscape‐scale prevalence and epidemiology of a little‐studied North American virus that was first detected in switchgrass and other grasses in bioenergy trials in the US Midwest. Switchgrass mosaic virus (SwMV, Genus Marafivirus, Family Tymoviridae) is transmitted by leafhoppers and is phylogenetically a sister to Maize rayado fino virus, a significant pathogen of maize in parts of the Americas. Our goal was to determine whether SwMV is uniquely limited to specific bioenergy trials or well‐established and circulating more broadly. We used molecular diagnostics to quantify naturally occurring SwMV infection in leafhoppers and switchgrass in naturalistic stands throughout a large Midwestern landscape, and quantified leafhopper abundances and stand performance. Our analysis revealed that this apparently wild virus is well‐established and widespread. Infection was present at nearly all sites, across diverse landscape contexts, with its prevalence ranging as high as 33%–60%. Infection appeared to accumulate and persist in stands over time. It was associated with increases in premature stand senescence but not with reductions in stand height. Although wild viruses are believed to evolve benign relationships with their natural hosts, these data suggest that SwMV has the potential to impact yield components. Viruses are frequently overlooked in crop development efforts, but they represent the majority of emerging plant pathogens. For SwMV, it is imperative to quantify its impact on host performance, to identify the extent of any host resistance, and to assess any risks of virus spillover to agricultural plantings of other Poaceae species, including maize and sorghum. [ABSTRACT FROM AUTHOR]

Polyphagous insects are characterized by a broad diet comprising plant species from different taxonomic groups. Within these insects, migratory species are of particular interest, given that they encounter unpredictable environments, with abrupt spatial and temporal changes in plant availability and density. Aster leafhoppers (Hemiptera: Cicadellidae: Macrosteles quadrilineatus Forbes) arrive in the Canadian Prairies in spring and early summer and are the main vector of a prokaryotic plant pathogen known as Aster Yellows Phytoplasma (AYp) (Candidatus Phytoplasma asteris). Host choice selection behavior of Aster leafhoppers was evaluated through two-choice bioassays, using domesticated and wild plants species commonly found in the Canadian Prairies. Leaf tissues from these plants were collected and stained to quantify the number of stylet sheaths and eggs. To assess possible effects due to insect infection, two-choice bioassays were repeated using leafhoppers infected with AYp and a subset of plant species. When two domesticated or wild plant species were presented together, similar numbers of uninfected Aster leafhoppers were observed on both plant species in most combinations. In domesticated–wild plant bioassays, uninfected Aster leafhoppers preferred to settle on the domesticated species. There was little to no association between settling preferences and stylet sheath and egg counts. These findings provide a better understanding of AY epidemiology and suggest that after domesticated species germination, leafhoppers could move from nearby wild plants into the preferred cereals (Poales: Poaceae) to settle on them, influencing the risk of AYp infection in some of these species. [ABSTRACT FROM AUTHOR]

Melanization in the hemolymph of arthropods is a conserved defense strategy against infection by invading pathogens. Numerous plant viruses are persistently transmitted by insect vectors, and must overcome hemolymph melanization. Here, we determine that the plant rhabdovirus rice stripe mosaic virus (RSMV) has evolved to evade the antiviral melanization response in the hemolymph in leafhopepr vectors. After virions enter vector hemolymph cells, viral nucleoprotein N is initially synthesized and directly interacts with prophenoloxidase (PPO), a core component of the melanization pathway and this process strongly activates the expression of PPO. Furthermore, such interaction could effectively inhibit the proteolytic cleavage of the zymogen PPO to active phenoloxidase (PO), finally suppressing hemolymph melanization. The knockdown of PPO expression or treatment with the PO inhibitor also suppresses hemolymph melanization and causes viral excessive accumulation, finally causing a high insect mortality rate. Consistent with this function, microinjection of N into leafhopper vectors attenuates melanization and promotes viral infection. These findings demonstrate that RSMV N serves as the effector to attenuate hemolymph melanization and facilitate viral persistent propagation in its insect vector. Our findings provide the insights in the understanding of ongoing arms race of insect immunity defense and viral counter-defense.

Integrative taxonomy is considered a reliable taxonomic approach of closely related and cryptic species by integrating different sources of taxonomic data (genetic, ecological, and morphological characters). In order to infer the boundaries of seven species of the evacanthine leafhopper genus Bundera Distant, 1908 (Hemiptera: Cicadellidae), an integrated analysis based on morphology, mitochondrial DNA, and hyperspectral reflectance profiling (37 spectral bands from 411-870nm) was conducted. Despite their morphological similarities, the genetic distances of the cytochromec oxidase subunitI (COI) gene among the tested species are relatively large (5.8-17.3%). The species-specific divergence of five morphologically similar species (Bundera pellucida and Bunderaspp.1-4) was revealed in mitochondrial DNA data and reflectance profiling. A key to identifying males is provided, and their morphological characters are described. Average reflectance profiles from the dorsal side of specimens were classified based on linear discriminant analysis. Cross-validation of reflectance-based classification revealed that the seven species could be distinguished with 91.3% classification accuracy. This study verified the feasibility of using hyperspectral imaging data in insect classification, and our work provides a good example of using integrative taxonomy in studies of closely related and cryptic species.

Integrative taxonomy is considered a reliable taxonomic approach of closely related and cryptic species by integrating different sources of taxonomic data (genetic, ecological, and morphological characters). In order to infer the boundaries of seven species of the evacanthine leafhopper genus Bundera Distant, 1908 (Hemiptera: Cicadellidae), an integrated analysis based on morphology, mitochondrial DNA, and hyperspectral reflectance profiling (37 spectral bands from 411-870nm) was conducted. Despite their morphological similarities, the genetic distances of the cytochromec oxidase subunitI (COI) gene among the tested species are relatively large (5.8-17.3%). The species-specific divergence of five morphologically similar species (Bundera pellucida and Bunderaspp.1-4) was revealed in mitochondrial DNA data and reflectance profiling. A key to identifying males is provided, and their morphological characters are described. Average reflectance profiles from the dorsal side of specimens were classified based on linear discriminant analysis. Cross-validation of reflectance-based classification revealed that the seven species could be distinguished with 91.3% classification accuracy. This study verified the feasibility of using hyperspectral imaging data in insect classification, and our work provides a good example of using integrative taxonomy in studies of closely related and cryptic species.

Simple Summary: Atkinsoniella is a large genus of 98 species across the world and 88 species recorded in China within the globally distributed subfamily Cicadellinae, which is phytophagous, and some of which have been reported as important agricultural pests. Some Atkinsoniella species are very similar in morphological characteristics, making accurate identification at species level confusing. To provide further evidence toward understanding the relationships within the genus Atkinsoniella and subfamily Cicadellinae, mitogenomes of 12 Atkinsoniella sibling species were obtained and annotated. Their characteristics were comparatively analyzed. In addition, the comprehensive phylogenetic relationship within the subfamily Cicadellinae was determined based on three mitochondrial datasets using both the maximum-likelihood (ML) and Bayesian inference (BI) methods. The results suggested that the genus Atkinsoniella was recovered as a monophyletic group. The branches of the 12 newly sequenced species were clearly separated, with most nodes receiving strong support in all analyses, indicating that mitogenomics is an effective method for identifying closely related species and understanding their phylogenetic and evolutionary relationships. The herbivorous leafhopper genus Atkinsoniella Distant, 1908 (Hemiptera: Cicadellidae: Cicadellinae), a large genus of subfamily Cicadellinae, consists of 98 valid species worldwide and 88 species recorded in China. Some species of the genus are very similar in morphological characteristics, so they are difficult to identify accurately. In this study, 12 mitochondrial genomes of Atkinsoniella species with similar morphological characteristics were first obtained through high-throughput sequencing, which featured a typical circular molecule of 15,034–15,988 bp in length. The arrangement and orientation of 37 genes were identical to those of typical Cicadellidae mitogenomes. The phylogenetic relationship within the subfamily Cicadellinae was reconstructed using maximum-likelihood (ML) and Bayesian inference (BI) methods based on three concatenated datasets. The topological structures of the six obtained phylogenetic trees were highly consistent. The results suggested that Atkinsoniella was recovered as a monophyletic group and emerged as a sister group with the monophyletic clade of Bothrogonia, Paracrocampsa (part), and Draeculacephala (part). The branches of the 12 newly sequenced species were clearly separated, with most nodes receiving strong support in all analyses. In addition, the key to the 12 Atkinsoniella species was provided to identify species according to morphological characteristics. This study further promotes research on the classification, genetics, evolution, and phylogeny of the genus Atkinsoniella and subfamily Cicadellinae. [ABSTRACT FROM AUTHOR]

A new species of Hanshumba Young, 1977 is described and illustrated from the Mantiqueira mountain range (southeastern Brazil), municipalities of Wenceslau Braz (state of Minas Gerais) and São Bento do Sapucaí (state of São Paulo). The new taxon is associated with olive orchards and is considered a potential vector of the bacterium Xylella fastidiosa. This bacterium causes a serious disease known in Brazil as olive leaf desiccation syndrome. Hanshumba mariae sp. nov. can be distinguished from the other five known species of the genus by the following combination of features: (1) apical third of ventral margin of male pygofer with small inner process bearing setae; (2) male abdominal segment X (anal tube) without processes; (3) style with apex narrow, obtuse, not foot-shaped; (4) aedeagus with distinct dorsal lobe along basal two-thirds and with apical portion expanded, bearing dorsal projection; (5) paraphyses with distal pair of rami forceps-like, their basal halves divergent from each other, distal halves approximately parallel, apices acute; (6) female sternite VII with posterior margin shallowly emarginate, bearing slight median lobe; and (7) valvula II of ovipositor with approximately 15 low teeth. Both males and females of the new species are described in detail. A key to the six known species of the genus is provided. [ABSTRACT FROM AUTHOR]

Soosiulus belterrensis sp. nov. is described and illustrated from the Amazon Forest of the state of Pará, northern Brazil. Both the male and female terminalia are treated in detail, in addition to color features. With the addition of this new taxon, the diverse Neotropical genus Soosiulus Young, 1977 now comprises 28 species. The new species is the first one proposed for Soosiulus after the original generic description. It appears to be included in a complex with eleven other Soosiulus species, all of them sharing a very similar color pattern. Among the members of this putative complex, the aedeagus of S. belterrensis sp. nov. is most similar to those of S. hastatus Young, 1977 and S. ruber Young, 1977, due to the presence of a pair of conspicuous dorsoapical processes. However, in S. hastatus and S. ruber the aedeagus has also a retrorse ventroapical process originated from a lobe; both process and lobe are not present in the new species. In addition, the female sternite VII in S. hastatus and S. ruber is convex posteriorly, whereas it has a distinct median emargination in the new species. [ABSTRACT FROM AUTHOR]

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Two location trials were conducted in 2018 dry season at the Teaching and Research Farm, Faculty of Agriculture, University of Maiduguri (Unimaid) and demonstration site of the Mohamet Lawan College of Agriculture (MOLCA) Maiduguri to assess the insecticidal potentials of three botanicals and a control in the management of Attractomorpha acutipennis, Amarasca biguttula biguttula, Aphis gossypii and Bemisia tabaci infestation on okra. These treatments were laid out in randomized complete block design (RCBD) replicated three times. Data collected include the number of damaged and undamaged leaves and the number of insect pests. Using Analysis of variance (ANOVA), results showed that the extracts significantly (p < 0.05) reduced the population of the insects and the number of damaged leaves when compared with control in both locations. Plots treated with Balanite aegytiaca extract recorded the lowers population of Attractomorpha acutipennis, A. biguttula biguttula, A. gossypii and B. tabaci. Similarly, Balanite aegytiaca extract recorded the lower leaves damaged than plots treated with Eucalyptus camaldulensis extract in both locations. Among all the treatments evaluated, Plots treated with Balanite aegytiaca extract significantly recorded the least number of A. gossypii and A. biguttula biguttula in both locations. However, plots treated with Balanite aegytiaca extract significantly gave the least number of B. tabaci at MOLCA while plots treated with Eucalyptus camaldulensis extract gave the least number of the insect at UNIMAID. There was no significant difference in the performance of Balanite aegytiaca and Eucalyptus camaldulensis extract. Balanite aegytiaca extract also recorded the least number of damaged leaves in both locations. [ABSTRACT FROM AUTHOR]

ABSTRACT A new species of the genus Dasmeusa Melichar, 1926 is described and illustrated from specimens collected in the State of Amazonas, Northern Brazil. Dasmeusa imperialis sp. nov. can be distinguished from the five known species of the genus, as well as from those of closely related genera, by the following combination of features: dorsum yellow with orange, preapical transverse irregular stripe on forewing; male pygofer moderately produced posteriorly, with posterior margin broadly rounded; style without preapical lobe, narrow and truncate apically; aedeagus with robust apical process directed ventrally, ventral margin of this process dentate; paraphyses with pair of dorsal dentiform projections on stalk, rami slender and directed posterodorsally; posterior margin of female sternite VII with small quadrate lobe; first ovipositor valvula with dentiform apex; second ovipositor valvula with apical third directed ventrally. This paper includes the first detailed description and illustrations of the female terminalia of a Dasmeusa species. In addition, the known geographic distribution of the genus is presented; D. pauperata (Fabricius, 1803) is newly recorded from the Brazilian states of Roraima, Amazonas, Pará, Sergipe, and Bahia; the records from the last two states are interesting because they are from areas of Atlantic Forest. Previously, the genus was known only from the Amazon Forest.

A new species of the Neotropical genus Platygonia Melichar, 1925 is described and illustrated from the municipality of Ipixuna, State of Amazonas, Northern Brazil. Platygonia nigra sp. nov. can be distinguished from the other species of the genus by the following combination of features: (1) dark brown to black ground color of dorsum; (2) presence of a white to pale yellow spot at the distal portion of corium; (3) male pygofer with a conspicuous diagonal cleft; (4) connective Y-shaped, keeled, with the stem longer than the arms; and (5) aedeagus with an unpaired basiventral process directed anteriorly. This is the first record of the genus from the Brazilian Amazon Rainforest. Notes on P. undecimmaculata (Fowler, 1899), which is a taxon of uncertain taxonomic position, a key to the species of Platygonia, and a map showing their distribution are added.

A morphology-based phylogeny of the Holarctic leafhopper genus Planaphrodes Hamilton is reconstructed for the first time based on 39 discrete male adult morphological characters. The results support the monophyly of Planaphrodes, with the included species forming two monophyletic lineages defined mainly by the number and location of aedeagus processes. The position of Planaphrodes in the Aphrodini was resolved as follows: (Stroggylocephalus + (Anoscopus + (Planaphrodes + Aphrodes))). The fauna of Planaphrodes from China, Japan and Korea are reviewed and six species are recognized, including two new species: P. bifasciatus (Linnaeus), P. sahlbergii (Signoret), P. nigricans (Matsumura), P. laevus (Rey), P. baoxingensis sp. nov. (China: Sichuan) and P. faciems sp. nov. (China: Hubei). Acocephalus alboguttatus Kato, 1933 syn. nov. and Aphrodes daiwenicus Kuoh, 1981 syn. nov. are considered junior synonyms of Planaphrodes sahlbergii (Signoret, 1879). Planaphrodes bella Choe, 1981 is a junior synonym of Planaphrodes nigricans (Matsumura, 1912). A checklist and key to species of Planaphrodes are provided.

Asian planthoppers (Hemiptera: Delphacidae) that include brown planthoppers (BPH, Nilaparvata lugens, Stål), white-backed planthoppers (WBPH, Sogatella furcifera, Horváth), and small brown planthoppers (SBPH, Laodelphax striatellus, Fallén) are the primary sucking-type pests of rice. These three insects share morphological and sequence similarities. As insecticide resistance patterns and control strategies vary according to species, the accurate discrimination of these species is important. Here, we developed six species-specific primers based on partial mitochondrial genome sequences. The primers were successfully used in multiplex PCR, loop-mediated isothermal amplification (LAMP) assays, and conventional PCR. Here, we used genomic DNA obtained using the DNA-releasing technique (tissue samples were incubated at 95 °C for 5 min with 30 μL nuclease-free water, and the supernatant was used). We showed that multiplex PCR could analyze the density of each species following a mass collection in the field; the LAMP assay can diagnose the species within 40 min; conventional PCR can be widely applied to a large number of field samples, as well as individuals or mass collections. In conclusion, these results demonstrate the potential of the species-specific primers and DNA-releasing technique for accurate multiplex PCR and LAMP assays, which may assist the intensive field monitoring of integrated management of these species.

Plant jasmonoyl-L-isoleucine (JA-Ile) is a major defense signal against insect feeding, but whether or how insect salivary effectors suppress JA-Ile synthesis and thus facilitate viral transmission in the plant phloem remains elusive. Insect carboxylesterases (CarEs) are the third major family of detoxification enzymes. Here, we identify a new leafhopper CarE, CarE10, that is specifically expressed in salivary glands and is secreted into the rice phloem as a saliva component. Leafhopper CarE10 directly binds to rice jasmonate resistant 1 (JAR1) and promotes its degradation by the proteasome system. Moreover, the direct association of CarE10 with JAR1 clearly impairs JAR1 enzyme activity for conversion of JA to JA-Ile in an in vitro JA-Ile synthesis system. A devastating rice reovirus activates and promotes the co-secretion of virions and CarE10 via virus-induced vesicles into the saliva-storing salivary cavities of the leafhopper vector and ultimately into the rice phloem to establish initial infection. Furthermore, a virus-mediated increase in CarE10 secretion or overexpression of CarE10 in transgenic rice plants causes reduced levels of JAR1 and thus suppresses JA-Ile synthesis, promoting host attractiveness to insect vectors and facilitating initial viral transmission. Our findings provide insight into how the insect salivary protein CarE10 suppresses host JA-Ile synthesis to promote initial virus transmission in the rice phloem., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Catalase (CAT) is the main reactive oxygen species (ROS)-scavenging enzyme in plants and insects. However, it remains elusive whether and how insect saliva CAT suppresses ROS-mediated plant defense, thereby promoting initial virus transmission by insect vectors. Here, we investigated how leafhopper Recilia dorsalis catalase (RdCAT) was secreted from insect salivary glands into rice phloem, and how it was perceived by rice chaperone NO CATALASE ACTIVITY1 (OsNCA1) to scavenge excessive H 2 O 2 during insect-to-plant virus transmission. We found that the interaction of OsNCA1 with RdCAT activated its enzymatic activity to decompose H 2 O 2 in rice plants during leafhopper feeding. However, initial insect feeding did not significantly change rice CATs transcripts. Knockout of OsNCA1 in transgenic lines decreased leafhopper feeding-activated CAT activity and caused higher H 2 O 2 accumulation. A devastating rice reovirus activated RdCAT expression and promoted the cosecretion of virions and RdCAT into leafhopper salivary cavities and ultimately into the phloem. Virus-mediated increase of RdCAT secretion suppressed excessive H 2 O 2 , thereby promoting host attractiveness to insect vectors and initial virus transmission. Our findings provide insights into how insect saliva CAT is secreted and perceived by plant chaperones to suppress the early H 2 O 2 burst during insect feeding, thereby facilitating viral transmission., (© 2024 The Author(s). New Phytologist © 2024 New Phytologist Foundation.)

Relative efficacy of various botanicals and biopesticides against major insect pests on brinjal was evaluated under field conditions during rabi 2018-2019. The results showed that two applications of neem + pungam oil @ 20 ml/l was significantly the most effective with reduction of sucking pests (leaf hopper, 70.20%; aphid, 60.54%; whitefly, 72.49%). Ginger + garlic rhizome extract @20 ml/l was observed to be the next best. Shoot and fruit borer damage reduction was also maximum in neem + pungam oil treatment with 66.97% shoot and 64.16% fruit damage followed by ginger + garlic rhizome extract with 61.57% shoot and 56.32% fruit damage. Neem + pungam oil led to maximum yield of 12.25 t/ha, followed by ginger + garlic rhizome extract (11.06 t/ha). [ABSTRACT FROM AUTHOR]

Homalodisca vitripennis (Hemiptera: Cicadellidae), known as the glassy-winged sharpshooter, is a xylem feeding leafhopper and an important agricultural pest as a vector of Xylella fastidiosa, which causes Pierce's disease in grapes and a variety of other scorch diseases. The current H. vitripennis reference genome from the Baylor College of Medicine's i5k pilot project is a 1.4-Gb assembly with 110,000 scaffolds, which still has significant gaps making identification of genes difficult. To improve on this effort, we used a combination of Oxford Nanopore long-read sequencing technology combined with Illumina sequencing reads to generate a better assembly and first-pass annotation of the whole genome sequence of a wild-caught Californian (Tulare County) individual of H. vitripennis. The improved reference genome assembly for H. vitripennis is 1.93-Gb in length (21,254 scaffolds, N50¼650Mb, BUSCO completeness ¼ 94.3%), with 33.06% of the genome masked as repetitive. In total, 108,762 gene models were predicted including 98,296 protein-coding genes and 10,466 tRNA genes. As an additional community resource, we identified 27 orthologous candidate genes of interest for future experimental work including phenotypic marker genes like white. Furthermore, as part of the assembly process, we generated four endosymbiont metagenome-assembled genomes, including a high-quality near complete 1.7-Mb Wolbachia sp. genome (1 scaffold, CheckM completeness = 99.4%). The improved genome assembly and annotation for H. vitripennis, curated set of candidate genes, and endosymbiont MAGs will be invaluable resources for future research of H. vitripennis. [ABSTRACT FROM AUTHOR]

Agroecosystems undergo frequent anthropogenic disturbance that may affect the diversity, community, and abundance of natural enemies living there. In the tropics, annual crops such as maize are planted two times (year-round crops) or one time (seasonal crops) per year. Little is known about how natural enemies of insect pests respond to maize agroecosystems planted one vs. two times during each annual cycle. The objective was to investigate the diversity and parasitism of egg parasitoids of the pest Dalbulus maidis (DeLong) (Hemiptera: Cicadellidae) in maize agroecosystems planted year-round and seasonally. Potted maize plants with D. maidis eggs were placed within these two maize agroecosystems to attract egg parasitoids during the maize-growing wet season in Mexico. In these two maize agroecosystems, similar levels of diversity were found, using the Shannon-Wiener index (H ′). Communities of parasitic wasps were found attacking the eggs of D. maidis in both maize agroecosystems, but there were differences in the composition of these communities. In the year-round maize agroecosystem, Paracentrobia sp. near subflava (Girault) (Hymenoptera: Trichogrammatidae) was the most common, while Anagrus virlai Triapitsyn (Hymenoptera: Mymaridae) was most common in the seasonal maize. A greater total abundance and total rate of parasitoid emergence were found in the year-round maize agroecosystem compared with the seasonal maize. In addition, a positive relationship between the number of D. maidis eggs and parasitoid abundance was found in both maize agroecosystems. However, a negative density dependence between the number of D. maidis eggs and the percentage of parasitism was found in both maize agroecosystems. [ABSTRACT FROM AUTHOR]

A total 76 germplasm accessions of wild okra (Abelmoschus moschatus ssp. moschatus) along with 4 checks were evaluated against okra leafhopper Amarasca biguttula biguttula Ishida in field condition during kharif 2017 and 2019. Of the 76 wild okra accessions used for two years of field screening, negligible preference of okra leafhopper insect exhibited towards nine wild okra accessions namely EC360586, EC360794, EC360830, EC360900, EC359730, EC359836, EC359870, EC360351 and EC361171 with hopper population in the range of 1.33 to 1.44/leaf while moderate preference of okra leafhopper was observed to another 11 wild okra accessions during first year of field screening (kharif 2017). During the second year (kharif 2019) of field screening, negligible preference of okra leafhopper was recorded on five accessions, viz. EC360586, EC360794, EC360830, EC360900 and EC361171 with hopper population in the range of 1.33 to 1.45/leaf while moderate preference response of okra leafhopper was observed on two wild okra accessions only. Whereas, high to very high preference response of okra leafhopper was observed on the remaining wild okra accessions during both the years of field screening and all were found susceptible. Based on two years field screening of wild okra accessions against okra leafhopper, five wild okra accessions, viz. EC360586, EC360794, EC360830, EC360900 and EC361171 were found resistant against okra leafhopper. The hopper burn symptoms were also negligible on these 5 accessions.

Due to the increasing popularity of websites specializing in nature documentation, there has been a surge in the number of people enthusiastic about observing and documenting nature over the past 2 decades. These citizen scientists are recording biodiversity on unprecedented temporal and spatial scales, rendering data of tremendous value to the scientific community. In this study, we investigate the role of citizen science in increasing knowledge of global biodiversity through the examination of notable contributions to the understanding of the insect suborder Auchenorrhyncha, also known as true hoppers, in North America. We have compiled a comprehensive summary of citizen science contributions—published and unpublished—to the understanding of hopper diversity, finding over fifty previously unpublished country and state records as well as dozens of undescribed and potentially undescribed species. We compare citizen science contributions to those published in the literature as well as specimen records in collections in the United States and Canada, illuminating the fact that the copious data afforded by citizen science contributions are underutilized. We also introduce the website Hoppers of North Carolina, a revolutionary new benchmark for tracking hopper diversity, disseminating knowledge from the literature, and incorporating citizen science. Finally, we provide a series of recommendations for both the entomological community and citizen science platforms on how best to approach, utilize, and increase the quality of sightings from the general public.

The first two complete mitogenomes of the leafhopper genus Cladolidia (C. biungulata and C. robusta) were sequenced and annotated to further explore the phylogeny of Cladolidia. Both the newly sequenced mitogenomes have a typical circular structure, with lengths of 15,247 and 15,376 bp and A + T contents of 78.2% and 78%, respectively. We identified a highly conserved genome organization in the two Cladolidia spp. through comparative analysis that included the following assessments: genome content, gene order, nucleotide composition, codon usage, amino acid composition, and tRNA secondary structure. Moreover, we detected the base heterogeneity of Cicadellidae mitogenomic data and constructed phylogenetic trees using the nucleotide alignments of 12 subfamilies of 58 leafhopper species. We noted a weak heterogeneity in the base composition among the Cicadellidae mitogenomes. Phylogenetic analyses showed that the monophyly of each subfamily was generally well supported in the family Cicadellidae; the main topology was as follows: (Deltocephalinae + (Treehoppers + ((Megophthalminae + (Macropsinae + (Hylicinae + (Coelidiinae +Iassinae)) + (Idiocerinae + (Cicadellinae + (Typhlocybinae + (Mileewinae + (Evacanthinae +Ledrinae)))))))))). Within Coelidiinae, phylogenetic analyses revealed that C. biungulata and C. robusta belong to Coelidiinae and the monophyly of Cladolidia is well supported. In addition, on the basis of complete mitogenome phylogenetic analysis and the comparison of morphological characteristics, we further confirm the genus Olidiana as a paraphyletic group, suggesting that the genus may need taxonomic revisions. [ABSTRACT FROM AUTHOR]

Singapora shinshana is a leafhopper native to mid‐Asia with a specific host range and is one of the least studied species within the genus. Recently, the species has been found to cause significant damage to host plants including ornamental trees, normally inflicted by its sucking behavior. This study uncovered more details on host and season preference of S. shinshana, damage potential and symptoms caused by its feeding behavior on ornamental trees in Korea, in addition to other records of other leafhoppers of economic importance. During the sticky trap survey period from 2017 to 2019, 12 leafhopper species were recovered from the eight selected ornamental tree species. Singapora shinshana was the most dominant species, constituting 94.8% of the total collected leafhopper population; with its highest incidence observed on Prunus serrulata, followed by Elaeagnus umbellata and Pseudocydonia sinensis. The high abundance on P. serrulata correlated with high damaged leaf percentages of 94.2%, 95.2%, and 98.1% in October 2017, 2018, and 2019, respectively. Interestingly, in terms of damaged leaf percentage, Rosa hybrida and Zelkova serrata were the second and third most damaged hosts despite the significantly lower population of the leafhopper on these trees. Furthermore, S. shinshana counts increased from late‐July to late‐September, with the peak evident during early August. Prunus serrulata can therefore be taken as one of the main host plants of S. shinshana. However, the potential of the host to suffer damage is not limited to population densities of the pest alone but also susceptibility and tolerance of the host plant. [ABSTRACT FROM AUTHOR]

Intracellular polyamines (putrescine, spermidine, and spermine) have emerged as important molecules for viral infection; however, how viruses activate polyamines biosynthesis to promote viral infection remains unclear. Ornithine decarboxylase 1 (ODC1) and its antienzyme 1 (OAZ1) are major regulators of polyamine biosynthesis in animal cells. Here, we report that rice yellow stunt virus (RYSV), a plant rhabdovirus, could activate putrescine biosynthesis in leafhoppers to promote viral propagation by inhibiting OAZ1 expression. We observed that the reduction of putrescine biosynthesis by treatment with difluormethylornithine (DFMO), a specific nontoxic inhibitor of ODC1, or with in vitro synthesized dsRNAs targeting ODC1 mRNA could inhibit viral infection. In contrast, the supplement of putrescine or the increase of putrescine biosynthesis by treatment with dsRNAs targeting OAZ1 mRNA could facilitate viral infection. We further determined that both RYSV matrix protein M and ODC1 directly bind to the ODC-binding domain at the C-terminus of OAZ1. Thus, viral propagation in leafhoppers would decrease the ability of OAZ1 to target and mediate the degradation of ODC1, which finally activates putrescine production to benefit viral propagation. This work reveals that polyamine-metabolizing enzymes are directly exploited by a vector-borne virus to increase polyamine production, thereby facilitating viral infection in insect vectors. [ABSTRACT FROM AUTHOR]

Purpose: Beneficial soil microbes, such as rhizobia, engage in facultative symbioses in the roots of leguminous host plants to exchange nitrogen for products of photosynthesis, and these symbioses can be altered by biotic and abiotic factors. Here, we investigated how soil nitrate supply and aboveground insect herbivory interact to influence biological nitrogen fixation in Medicago sativa (alfalfa or lucerne). Methods: Using field and greenhouse experiments, we quantified above- and belowground allocation of rhizobially fixed nitrogen using isotopic nitrogen ratios in plants with different combinations of herbivory and nitrate supplementation. We caged Empoasca fabae (potato leafhopper) on fixing and non-fixing cultivars of M. sativa and supplemented soils with varied nitrate concentrations. Results: We detected strong changes in legume above- and belowground allocation of fixed nitrogen in response to both herbivory and nitrate supply. Moderate nitrate soils, irrespective of herbivory, induced little to no fixed nitrogen allocation across both field and greenhouse experiments. In the field only, non-supplemented soil increased aboveground allocation of fixed nitrogen following herbivore damage but resulted in no changes belowground. In contrast, non-supplemented and high nitrate soils in the greenhouse increased above- and belowground fixed nitrogen allocation relative to moderate nitrate soils. Conclusion: Our results demonstrate herbivory drives distinct plant allocation strategies across soil nitrate levels, advancing our understanding of how rhizobia influence legumes both above- and belowground. Herbivory-induced changes in rhizobia-legume symbioses are likely widespread across both agricultural and natural ecosystems. [ABSTRACT FROM AUTHOR]

1. Multivariate climate change is expected to impact insect densities and plant growth in complex, and potentially different, ways. Tea (Camellia sinensis) is a unique crop system where the increase in quality from chemical defences induced by Empoasca onukii (Homoptera: Cicadellidae) feeding can outweigh reductions in yield and make attack by this leafhopper desirable to tea farmers. Differential impacts of weather attributes on tea and herbivores could impact feasibility of this unique farming strategy in a rapidly changing climate. 2. We monitored leafhopper densities and tea shoot growth at a tea farm in Fujian Province, China for 2 months (June and July). We used distributed lag non‐linear models to capture potentially delayed and non‐linear effects of weather attributes on tea growth and leafhopper densities. 3. Weather attributes had contrasting effects on leafhopper density and tea shoot growth. Leafhopper densities were highest with low daily mean and maximum temperatures, while warm temperatures favoured tea growth. Effects of temperature on leafhoppers were delayed, while effects on tea growth were immediate. Precipitation reduced tea growth, and had a delayed positive effect on leafhopper density. 4. The delayed effects of weather attributes on leafhoppers indicate that earlier, less conspicuous life stages (i.e. eggs and early instar nymphs) may be susceptible to desiccation. Although increasing annual mean temperature is commonly predicted to benefit multivoltine insect pests, our results show that cool, wet conditions benefit E. onukii during summer months when they are most abundant. These results have implications for tea green leafhopper management strategies. [ABSTRACT FROM AUTHOR]

[Display omitted] • A total of 28, 27 and 25 sphingolipid species were detected in SBPH, WBPH and GRLH. • No C14 sphingoid-base was detected in GRLH. • The category of sphingomyelins varies in the three insect species. • The leafhopper possessed more SMase gene isoforms than planthoppers. Sphingolipids (SPLs), a group of membrane and intracellular lipids, mediate numerous cellular processes. The composition and metabolism of sphingolipids varies according to species and the sphingolipid studies of insects, as compared to mammals, are not yet clear. In the current study, we subjected three auchenorrhynchous insects, including whitebacked planthopper (WBPH), Sogatella furcifera , small brown planthopper (SBPH), Laodelphax striatellus, and green rice leafhopper (GRLH), Nephotettix cincticeps , as representative rice pests for sphingolipid analysis. We performed sphingolipid species profiling using UPLC-Q-TOF-MS/MS and isolated sphingolipid metabolic genes from their transcriptomic data. C14-, C16-, C18- and C20-sphingoid base were detected in both planthoppers, but no C14- sphingoid base was found in GRLH. The planthoppers had more abundant sphingosine-1-phosphates (Sph-1-P) and ceramides than leafhopper. A total of 14, 13 and 16 sphingomyelin species were found in SBPH, WBPH and GRLH, respectively. The composition of sphingomyelin species varied in three insects. Coordinated with the abundance in sphingomyelin species, the leafhopper possessed more sphingomyelinase (SMase) gene isoforms for metabolism of different sphingomyelins than planthoppers. The phylogenetic analysis showed the three tested insects all possessed one potential neutral-SMase homologue, whereas SBPH and GRLH both had another potential acid-SMase homologue. This study is a comprehensive sphingolipidomic analysis, suggesting that sphingolipid profiles significantly differed among the three insects. By providing information of sphingolipid metabolic gene homologues of these three insects, our findings will contribute to the further sphingolipid studies of auchenorrhynchous insects and provide a research foundation for rice pest management. [ABSTRACT FROM AUTHOR]

The study aimed to understand the defense mechanism of sunflower germplasm accessions against leafhopper, Amrasca biguttula biguttula Ishida. Changes in biochemical parameters, viz., total sugars, total free amino acids, total phenols, chlorophyll and moisture content were studied in relation to the expression of reaction in seven resistant, four susceptible germplasm accessions and the susceptible check, Morden due to leafhopper feeding. The results indicated that resistant accessions had higher total phenols (153.04 77 µg g-1 of GAE) and chlorophyll (36.71) than the susceptible accessions whereas, total free amino acid (316.94 mg g-1 fresh weight), total sugars (93.27 mg g-1 dry weight) and moisture content (83.61%) were higher in susceptible accessions. The leafhopper nymphal population showed a highly significant and negative correlation with total phenols (r= -0.919) and chlorophyll (r=-0.870), while total free amino acids (r=0.698) and total sugars (r=0.928) showed a highly significant and positive correlation with the leafhopper population. [ABSTRACT FROM AUTHOR]

The experimental trials were carried out during two consecutive years 2019 and 2020 at CRC, Chirrodi of SVPUAT, Meerut to report the insect pest complex associated with sugarcane in Western Uttar Pradesh. The eleven species of insect pests were observed to infest the sugarcane variety, Co 0238 at different stages of crop growth in an overlapping manner. The Early shoot borer, Chilo infuscatellus Snellen, Top borer, Scirpophaga excerptalis Walk. Root borer, Emmalocera depressella Swinhoe, Stalk borer, Chilo auricilius Dudgeon, leafhopper, Pyrilla perpusilla Walker, white grub, Holotrichia consanguinea (F.) and Termite, Odentotermes obesus Rambur were recorded as major insect pests whereas, Mealybug, Saccharicoccus sacchari Green, Black bug, Cavelerius excavates Slater, Woolly aphid, Ceratovacuna lanigera Zehntner, and Grasshopper, Schistocerca gregaria Walker were recorded as minor insect pests. Among the natural enemies of insect pests of sugarcane, six natural enemies were observed during the study period i.e. Praying mantids, Epiricania, Coccinellid, Dragonflies, Spiders and Earwig. The natural enemies, Coccinella septumpunctata L., Epiricania melanoleuca (F.) and Spiders played an important role to minimize the insect pest population of sugarcane during the study period. [ABSTRACT FROM AUTHOR]

We determined the complete mitochondrial genome (mitogenome) of the leafhopper Metidiocerus impressifrons by next-generation sequencing. The mitogenome sequence was 16,426 bp in length and consists of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, and a control region. Moreover, the nucleotide composition biases toward A and T, which together made up 78.2% of the entirety. The complete mitochondrial genomes of Metidiocerus impressifrons and other 27 species were used for phylogenetic analysis using the Bayesian method. The above results would facilitate our understanding of the evolution of Idiocerinae mitochondrial genome.

Despite its critical role in repelling damaging insects, our understanding of nonhost resistance against herbivores remains very limited. Recently, Bai et al. identified a novel caffeoylputrescine-green leaf volatile (GLV) compound in wild tobacco plants that confers nonhost resistance to Empoasca leafhoppers through high-throughput multi-omics analyses. [ABSTRACT FROM AUTHOR]