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The grassland leafhopper genus Maiestas Distant is reviewed from Pakistan with the description and illustrations of one new species, Maiestas sinuata Shah & Duan sp. n., and two new records, i.e., Maiestas maculata n. rec. and Maiestas trispinosa n. rec. A checklist of the known species of Maiestas from Pakistan is also given together with a key for their separation (males).

The corn leafhopper Dalbulus maidis is the main vector of the pathogens that cause corn stunt, a major disease of maize in the Americas. As host resistance is an efficient tool to control diseases, the findings of a previous report showed that some corn hybrids are resistant to D. maidis. In this work, we assessed the probing behavior of D. maidis on susceptible and resistant corn hybrids using EPG (Electrical Penetration Graph) technology. Fifteen-day-old females were monitored for 20 hours, with access to hybrids DK390, DK670, DK79-10, and DK72-10. Hybrids DK390 and DK72-10 showed resistance to D. maidis in phloem, since insects feeding on these hybrids presented more salivation events in phloem without subsequent ingestion, which are seen as failed attempts to ingest. A reduction of the total duration of phloem ingestion was observed, and accordingly of the time spent by insects with access to these hybrids on xylem ingestion. The hybrid DK390 also had mesophyll resistance, seen as less probing time and a higher number of probes of short duration. These findings support and are consistent with previous research, providing useful information to characterize maize hybrids resistant to D. maidis, and so to corn stunt.

A new Brazilian leafhopper genus of the subfamily Neocoelidiinae is proposed: Takiyaella gen. nov. based on T. sexguttata (Chiamolera & Cavichioli, 2003) gen. et comb. nov. and five new species: T. anomala gen. et sp. nov., T. coelhomarquesae gen. et sp. nov., and T. daniela gen. et sp. nov. from the state of Rio de Janeiro; T. cavichiolii gen. et sp. nov. from the state of Paraná, and T. mejdalanii gen. et sp. nov. from the state of Minas Gerais. A distribution map and identification key to Takiyaella species are provided.

The tea green leafhopper Empoasca onukii is one kind of insect pest threatening the tea production, and the mite Anystis baccarum has been used as an agent for pest control. In this paper, we introduce a generalist predator-prey model to study the dynamics for informing biological control. There have been some bifurcation studies of the generalist predator-prey model in the last few years. Except for the bifurcations include saddle-node bifurcation of codimension 1 and 2, Hopf bifurcations, and Bogdanov-Takens bifurcation of codimension 2 and 3, we also present the bifurcations of nilpotent singularities of elliptic and focus type of codimension 3. We find that the nilpotent singularities are associated with a cubic Lienard system, and the nilpotent bifurcations are three-parameter bifurcations of a codimension 4 nilpotent focus. Furthermore, we show that the nilpotent focus serves as an organizing center to connect all the codimension 3 bifurcations in the system. We also present the bifurcation diagrams to unfold the nilpotent singularities of codimension 3. One interesting observation is that we show numerically the existence of three limit cycles in the system .

Insect vectors horizontally transmit many plant viruses of agricultural importance. More than one-half of plant viruses are transmitted by hemipteran insects that have piercing-sucking mouthparts. During viral transmission, the insect saliva bridges the virus-vector-host because the saliva vectors viruses, and the insect proteins, trigger or suppress the immune response of plants from insects into plant hosts. The identification and functional analyses of salivary proteins are becoming a new area of focus in the research field of arbovirus-host interactions. This protocol provides a system to detect proteins in the saliva of leafhoppers using the plant host. The leafhopper vector Nephotettix cincticeps infected with rice dwarf virus (RDV) serves as an example. The vitellogenin and major outer capsid protein P8 of RDV vectored by the saliva of N. cincticeps can be detected simultaneously in the rice plant that N. cincticeps feeds on. This method is applicable for testing the salivary proteins that are transiently retained in the plant host after insect feeding. It is believed that this system of detection will benefit the study of hemipteran-virus-plant or hemipteran-plant interactions.

Rovnoxestus rasnitsyni gen. & sp. nov. is described from Eocene Rovno amber based on an adult female and fifth-instar nymph collected at a recently discovered locality at Perebrody, Rovno Province, Ukraine. The new fossil taxon is tentatively placed in Aphrodinae and resembles Xestocephalites Dietrich & Gonçalves from Eocene Baltic amber but has the hind femur macrosetal formula 2+2+1 and hind tarsomere I in both nymph and adult with an elongated inner preapical seta. This is the first species of Eocene leafhopper for which both the adult and nymph are described in detail.

A new Brazilian leafhopper genus of the subfamily Neocoelidiinae is proposed. Mejdalania gen. nov. is described based on three new species: Mejdalania bia sp. nov. from the state of Acre, M. longa sp. nov. from the state of Amazonas and M. unciformis sp. nov. from the state of Mato Grosso. A distribution map of Mejdalania species and an identification key for the species of the genus are provided.

Oh, Sumin, Kim, Eunji, Jung, Sunghoon (2021): One new and one newly recorded species of the genus Alneotidia Dlabola (Hemiptera: Auchenorrhyncha: Cicadellidae: Typhlocybinae) from the Korean Peninsula with key to Korean species. Zootaxa 5032 (4): 577-582, DOI: https://doi.org/10.11646/zootaxa.5032.4.7

The corn leafhopper Dalbulus maidis (Hemiptera: Cicadellidae) is a specialist herbivore that attacks maize in the tropical and subtropical regions of the Americas. It is vector of three relevant plant pathogens being responsible for severe yield losses. Modern agriculture is dependent on the addition of fertilizers, especially nitrogen, which may influence the nutritional quality of the plants possibly with a subsequent increment of herbivorous insect populations. Through a field experiment, using a randomized design with four treatments with different levels of fertilization, we evaluated the effects of nitrogen fertilization in corn on the population levels of the vector D. maidis, on the incidence of the diseases transmitted by it, and on the levels of parasitism of the vectors’ eggs. The amount of nitrogen fertilizer used significantly influenced the density of the corn leafhopper and the parasitism by egg parasitoids, but not the incidence of the diseases transmitted by it. Two weeks after fertilization, the vector density was significantly higher in the highly fertilized treatment. The disease incidence was not directly linked with the level of fertilization, however, the symptoms of the diseases were much less evident in plants that received higher fertilization. Parasitism levels by egg parasitoids increased accordingly to the level of D. maidis populations.

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, N50 = 650 Mb, BUSCO completeness = 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. Further, as part of the assembly process, we generated four endosymbiont metagenome-assembled genomes (MAGs), 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.

The genus Anufrievia Dworakowska is reviewed with two new species from China: A. anchoroides sp. nov., and A. drepanoides sp. nov.. Detailed morphological descriptions and illustrations of these two new species and a key to all known species (males) from China are provided.

The leafhopper genus Empoascanara Distant, 1918 encompasses 81 species, most of which are distributed in Afrotropical, Oriental and Australian Realm. The leafhopper genus Kapsa Dworakowska, 1972 encompasses 23 species, mainly known from the Oriental and Australian Realms. 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. Identification keys to the males of the genera Empoascanara and Kapsa in China are proposed.

The distribution of deltocephaline leafhopper Grypotes puncticollis (Herrich-Shaeffer, 1834) is analyzed, with emphasis on the records of this species from Kazakhstan which are currently defining its eastern border. Host plant records of G. puncticollis are summarized.

The present experiment was conducted in Zefta, Gharbia governorate to examine the influence of fertilization levels on the population density of the different leafhoppers and planthoppers attacking eggplant crop during the two successive seasons (2017and 2018). The potassium fertilization levels of zero kg/fed. to 25, 50, and 75 kg/fed. attracted the highest average number of the leafhopper and planthopper species during the two seasons. The present study indicated that increasing potassium fertilization rates from zero kg/fed. to 25, 50 and 75 kg/fed. led to a decline in the average number of the tested insect pests during the two years with significant differences. The potassium fertilization of 75 kg/fed. attracted the lowest percentage of occurrence of the tested insect pests and presented by 13.6 and 15.3 % during the two seasons 2017 and 2018, respectively.

The leafhopper genusOpsiusFieber, 1866 is revised for the Kingdom of Saudi Arabia. Seven species are treated, including three that previously were reported by Dlabola (1979),O. pallasi(Lethierry, 1874),O. tigripes(Lethierry, 1876), andO. versicolor(Distant, 1908).Opsius heydeni(Lethierry, 1876),O. richteriDlabola 1960, andO. scutellaris(Lethierry, 1874) are reported for the first time from the Kingdom. A new species,O. wilsoniEl-Sonbati,sp. nov.is described from the southwestern region of the Kingdom of Saudi Arabia. A key to the species ofOpsiusof the Kingdom is also provided.

Leafhoppers (Cicadellidae) occur in all biogeographical regions and feed on a wide range of host plants. Classic identification of leafhoppers is based only on the morphology of male genitalia, while DNA barcoding is an effective tool to identify different leafhopper species in any stage of their life cycle. Phylogenetic relationships among leafhoppers remain unexplored, but recent phylogenies have begun to interpret the evolutionary relationships of previously recognized tribes and subfamilies. Here we used mitochondrial Cytochrome Oxidase I sequences to barcode and determine the phylogenetic relationship among eight leafhopper genera collected from Egypt. Eight leafhopper samples from eight different genera were collected from various plants using a sweeping net and aspirator. Males of seven species were available while females only were available from the one genus (Austroagallia sp.). Novel leafhopper-specific mtDNA COI degenerate primers were designed. Our results showed that the mean of intraspecific COI sequence divergence in leafhoppers was 0.45%, with a range from 0.15% to 1.23%, and the divergences of most species were over 2%. For the first time, we were exploring the evolutionary relationships among surveyed genera (Austroagallia, Empoasca, Eupteryx, Exitianus, Macrosteles, Nephotettix, and Orosius) using a robust phylogenetic supertree. Our results demonstrate that DNA barcoding is likely to be a powerful tool for identifying and understanding leafhoppers’ evolution.

Leafhoppers (Hemiptera: Cicadellidae) form a large, diverse insect family that contributes significantly to trophic interactions and pathogen transmission in grasslands. We compared leafhopper communities of five remnant prairies and five prairie reconstructions in northeastern Kansas, USA. We hypothesized that leafhopper communities would be more conservative (i.e., greater dependence on prairies) and diverse on remnant as compared to reconstructed prairies, and that remnants would support more grass-feeders. We also predicted that sites surrounded by natural/semi-natural landscapes would have greater leafhopper diversity. We found grass feeders represented a higher proportion of leafhoppers on remnants. We found, however, no difference in mean conservatism between remnants and reconstructions, and overall levels of conservatism were lower than other grassland data sets. Mean conservatism was greater in the mid-summer than in early summer, where migratory pests such as Macrosteles were abundant. Although remnants and reconstructed prairies didn’t differ in leafhopper diversity, diversity increased with forb percent cover. The amount of natural and semi-natural land cover around sites had complex relationships with leafhopper diversity and composition. For future studies, we encourage coordinated studies on leafhopper communities across the tallgrass prairie region, with a particular focus on conservatism. Deciphering the effect of survey times, and grassland size and management, on prairie-dependent leafhoppers is important. We predict that large numbers of migratory species may lead to greater homogeneity in leafhopper communities across sites early in the season. Over time, site types and landscape features may progressively filter species and amplify local specialists, resulting in more late-season variation among sites.

Thirteen volatile compounds were identified from Flemingia macrophylla plants. Eight major components significantly attracted the tea green leafhoppers, Empoasca flavescens F. Based on their relative abundances, following synthetic blends were made for field experiments: 1) eight-component-attractant blend included Z-3-hexen-1-ol, Z-3-hexenyl acetate, Z-ocimene, MeSA, Z-3-hexenyl butyrate, dodecane, hexadecane and nonanal at 10, 10, 1, 11, 2, 6, 2 and 4 mg mL−1 in n-hexane, respectively; 2) four-component-attractant blend #1 contained hexadecane, Z-3-hexenyl acetate, Z-3-hexen-1-ol and nonanal at 2, 10, 10 and 4 mg mL−1 in n-hexane, respectively; 3) four-component-attractant blend #2 contained hexadecane, Z-3-hexenyl acetate, Z-3-hexen-1-ol and MeSA at 2, 10, 10 and 11 mg mL−1 in n-hexane, respectively. Thymol and 1-methoxy-4-methyl-2-(1-methylethyl)-benzene, identified from Lavandula angustifolia aeration samples, significantly repelled the leafhopper as strong repellents when tested alone or in combination at 10 mg mL−1. For field bioassays, each attractant lure was attached to a bud green sticky board hung from a bamboo stick at above tea plant level for catching the leafhoppers, whereas the repellent dispenser was tied to a tea branch inside tea clump for pushing the leafhoppers away from tea clumps. The results showed that the eight-component-attractant blend caught similar numbers of the leafhopper as did the four-component-attractant blend #1 at about 53–79 leafhoppers/trap/day, which were significantly higher than those on the hexane-control bud green sticky boards. Average leafhopper catches from un-baited sticky boards were about 51–73 leafhoppers/trap/day when pushed by the repellents placed inside tea plants, with the two-component-repellent blend being more effective than their single components. When the two-component-repellent blend was further tested with the three attractant blends in a push-pull fashion, average trap catches ranged from 62 to 92 leafhoppers/trap/day. Control efficacy on the leafhoppers within the push-pull zones increased progressively from day 1 (43%) to day 5 (73%). This push-pull approach might have a great potential as a green control strategy for combating the tea green leafhoppers.

CavichianaMejdalani et al., 2014 was a formerly monotypic Cicadellinae genus exclusively found in bromeliads from southeastern Brazil. Here a new species is described, diagnosed, and illustrated from Itatiaia National Park, municipality of Itamonte, state of Minas Gerais (Mantiqueira mountain range); specimens were collected on Vriesea spp. (Bromeliaceae). Cavichiana alpina sp. nov. (male holotype in DZRJ) can be recognized by the following combination of features: (1) forewing clavus with basal portion and area along commissural margin orange, remainder of claval area blue (except dark brown apex); (2) corium with large blue area adjacent to claval sulcus, connected to blue area of clavus; (3) distal portion of female and male pygofer not sclerotized; (4) aedeagus with distinct basidorsal lobe and with apex narrowly rounded, not bearing crown of spines; and (5) female sternite VII with deep V-shaped posterior emargination. Notes on the distribution of the genus are provided and C. bromelicolaMejdalani et al., 2014 is newly recorded from southern Brazil.

Wheat yellow striate virus (WYSV), which is found in wheat fields of Northwest China and transmitted by leafhopper vector Psammotettix alienus, is a tentative new species in the genus Nucleorhabdovirus. Although the insect vector and host range of WYSV have been characterized, many aspects of the acquisition and transmission processes by its insect vector have not been elucidated. Here, the transmission parameters of WYSV by P. alienus were determined using wheat cv. Yangmai 12 as the indicator plant under a controlled temperature (23 ± 1°C) and photoperiod (16 h of light). The results showed that the minimum periods for acquisition were 5 min and 10 min for inoculation access. The latent period for successful transmission was most commonly 16 to 20 days (minimum, 10 days; maximum, 22 days). The quantitative reverse-transcriptase PCR results indicated that the WYSV titer increased with time after acquisition, suggesting that WYSV can replicate in P. alienus. Notably, female P. alienus transovarially transmitted the virus to next generations at relatively high efficiency. Electron microscopy of the WYSV-infected leafhopper revealed bacilliform particles aggregated in the cytoplasm of the salivary gland and midgut tissues. Our present studies suggested that acquisition and transmission of WYSV by P. alienus is consistent with a propagative, circulative, and persistent mode of transmission. Details regarding transmission competencies and distribution of WYSV in P. alienus will provide a basis for designing preventive measures.

A new leafhopper genus, Fanjingagen. nov., with type species F. digitata Yu & Yang, sp. nov., is described from the Guizhou Province of Southwest China. Habitus photos and illustrations of male genitalia of the new species are provided.

Pest growth is closely related to the climate conditions. This study aimed to analyze the impact of climate variability and climate change on the potential attack of green leafhopper (Empoasca sp.) on tea plantations at PTPN VIII Gunung Mas. The analysis was carried out to calculate the value of Ecoclimatic Index (EI) based on the functions of the compare years and the compare location in CLIMEX model. Pest suitability in the future was projected using RCP 4.5 and 8.5 climate scenarios, which were derived from MIROC 5 and CCSM 4 climate model outputs. The result indicated that Gunung Mas Tea Plantation was suitable for Empoasca sp. growth. The EI value (58) in the baseline year (2012-2017) confirmed the suitability. Climate variability influences the suitability for Empoasca sp. growth. During El-Niño, the EI value decrease substantially (~26%). On the other hand, the EI value is projected to slightly increase in the future for both climate scenarios.

The tribe Agalliini is reviewed from Pakistan with additional description and illustration of a new record Anaceratagallia pararobusta (Pruthi) 1936. An updated checklist and keys are given to distinguish all the genera and species of the tribe Agalliini from Pakistan.

Rice stripe mosaic virus (RSMV) is a rhabdovirus recently found in southern part of China and can cause severe reduction in rice production. To establish serological methods for RSMV epidemiological studies and to establish a control strategy for this virus, we first purified RSMV virions from infected rice plants and then used them as an immunogen to produce four RSMV-specific monoclonal antibodies (MAbs) (i.e.,1D4, 4A8, 8E4 and 11F11). With these MAbs, we have developed a highly specific and sensitive antigen-coated plate enzyme-linked immunosorbent assay (ACP-ELISA), a Dot-ELISA and a Tissue print-ELISA for rapid detections of RSMV infection in rice plants or in leafhoppers. Our results showed that RSMV can be readily detected in RSMV-infected rice plant tissue crude extracts diluted at 1:20,971,520 (w/v, g/mL) through ACP-ELISA or diluted at 1:327,680 (w/v, g/mL) through Dot-ELISA. Both ACP-ELISA and Dot-ELISA can also be used to detect RSMV infection in individual RSMV viruliferous leafhopper (Recilia dorsalis) homogenate diluted at 1:307,200 and 1:163,840 (individual leafhopper/µL), respectively. Detection of RSMV infection in field-collected rice samples or in RSMV viruliferous leafhoppers indicated that the three serological methods can produce same results with that produced by RT-PCR (19 of the 33 rice samples and 5 of the 16 leafhoppers were RSMV-positive). We consider that the four MAbs produced in this study are very specific and sensitive, and the three new serological methods are very useful for detections of RSMV infection in rice plants or in leafhoppers and the establishment of the disease control strategies.

The vector of Grapevine Flavescens Dorée phytoplasma, the American grapevine leafhopper (Scaphoideus titanus) has been in Europe since 1924. In Romania, the first populations were detected in 2009 in the central, eastern and southern part of the country. Later, the leafhopper was found also in West Romania in 2014. In 2015 and 2017, altogether, 14 sampling sites were studied in two vine regions of this area. The Scaphoideus titanus could be detected in 10 of them with relatively small abundances. During the studies, the yellow sticky traps proved more effective methods than sweep netting. To prevent vineyards from disease, we should do everything against the vector from prevention to chemical protection.

The present experiments were conducted to study the effect of different solanaceous host plants on the population density of the leafhoppers and planthoppers according to the morphological diversity of host surface and phytochemical composition on the preference behaviour of the insect pests during the two successive seasons 2017 and 2018 in Gharbia governorate. The leafhoppers, Empoasca decipiens and Empoasca decedens preferred eggplant as a host plant followed by tomato and pepper by using the three methods (leaf sample, yellow sticky traps, sweep net) during the two seasons. Meanwhile, Cicadulina chinai preferred tomato followed by eggplant and pepper by using the different methods. While, Balcutha hortensis preferred pepper followed by eggplant and tomato. On the other hand, the planthoppers, Sogatella futcifera preferred eggplant followed by pepper and tomato. Statistical analysis revealed that highly significant differences were recorded between the three host plants during the two seasons according to the average number of different leafhoppers and planthoppers by using the three sampling methods. Depending on the percentage of insect pest occurrence, sweep net recorded the highest percentage followed by yellow sticky traps and the lowest percentage of occurrence was recorded by leaf sample method. The insect population varied among leaf surface morphological characters. The Scanning Electron Microscope pictures revealed that, the trichome type was non-glandular in eggplant and tomato, while in pepper was hairiness. Population density exhibited significantly of trichome length on eggplant, whereas had less significantly on tomato leaves with higher hair density. Peppers, with no trichome had the lowest population of insect. Depending on the analysis of phytochemical composition of plant leaves, a highly positive correlated leafhopper and plant hoppers with higher ratios was found for the total protein, total nitrogen, α-esterase, β- esterase and Glutathione S-transferase (GST). However, the population density affected by the total ratio of carbohydrate of eggplant. While, there was a negative correlated between insect infestation and the contents of phenols, potassium, phosphorus and the plant soap acidity (pH), thus the population was high with low content of these components in eggplant followed by tomato then pepper. This study showed that the development of the host plant resistant to the insect pests is an important strategy of integrated pest management programs and the recognition of morphological and phytochemical characteristics may lead to develop resistance character in acceptable plant genotypes.

Background The tea leafhopper, Empoasca onukii Matsuda (Hemiptera: Cicadellidae), is a major pest of tea plants in China. Here, we evaluated the repellent properties of eight volatile chemicals alone and in various combinations as tools for the management of this pest in tea gardens. These chemicals were from the Alliaceae and other aromatic plants, and are known to repel various insect species. Results Among the eight volatile compounds, dimethyl disulfide (DMDS), 1,8-cineole and allyl methyl sulfide were significantly repellent towards E. onukii adults. DMDS and 1,8-cineole were mixed to formulate a binary repellent. Under field conditions, spraying and slow-release applications of the mixture significantly decreased the density of E. onukii adults. The repelling effect after spraying was very short, only ∼ 2 days, but the slow-release mixture had a longer term repelling effect on E. onukii adults. High emission of the slow-release mixture, which was achieved by increasing the number of slow-release bottles, had a stronger repellent effect than low emission. Moreover, when the amount emitted was sufficient, the slow-release mixture significantly decreased the number of leafhopper nymphs in a treated tea-plant line, and significantly decreased the number of leafhopper adults and nymphs in a tea-plant line adjacent to the treated area. Conclusion This study demonstrates the repellent action of a mixture of DMDS and 1,8-cineole applied by a slow-release method against E. onukii in a tea plantation. This mixture has potential applications in integrated pest management schemes. © 2019 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The phylogeny of the Oriental leafhopper genus Amritodus is reconstructed, for the first time, based on 47 discrete morphological characters and DNA sequence data from one nuclear and two mitochondrial genes. The phylogenetic results show that Amritodus is not monophyletic, and its concept is narrowed here to include four species: Amritodus atkinsoni, Amritodus brevis, Amritodus brevistylus and Amritodus saeedi. The phylogenetic results support establishment of a new genus, Paramritodus gen. nov., with three new species,Paramritodus triangulus sp. nov. (type species), Paramritodus introflexus sp. nov., Paramritodus spatiosus sp. nov. and three species previously included in Amritodus: Paramritodus pistacious comb. nov., Paramritodus flavocapitatus comb. nov. and Paramritodus podocarpus comb. nov. In addition, Amritodus flavoscutatus is transferred from Amritodus to Hyalinocerus as Hyalinocerus flavoscutatus comb. nov. Keys to species of Amritodus and Paramritodus are provided.

Effective insect management strategies require a firm understanding of the factors determining host preference, particularly in highly mobile insect herbivores. Host preference studies commonly employ average or first position as a proxy for preference. Yet few studies have explored host preference in relation to transitory attraction and leaving rates, yet these are both components of host plant selection. We investigated the transitory dynamics of preference by the green rice leafhopper, Nephotettix cincticeps (Uhler) (Hemiptera: Cicadellidae) by conducting experiments on groups of females, males, or mixed-sex leafhoppers, and recording their position over time between low-N and normal-N rice plants. Utilizing a log-linear model and variants of a biostatistical model we used these positional data to extract attraction, leaving and tenure rates to better understand the process of host-plant selection. We found a general preference for normal-N over low-N plants at equilibrium. However, between sexes there was variation in the relative significance of attraction or leaving rates on that preference. Female leafhoppers were more attracted to host plants with higher nitrogen content. Male leafhoppers were less discriminate in their initial attraction to hosts but left low-N hosts at a faster rate. Whereas estimated tenure times on both normal- and low-N plants exceeded transmission times for the leafhopper-transmitted rice dwarf virus, longer tenure on normal-N plants likely increases the likelihood of virus acquisition from these plants. Our findings support previous recommendations that growers can mitigate the risks of leafhopper damage and pathogen transmission by optimizing their application of nitrogenous fertilizers.

Monitoring data on new invasive grape pests in the Western Ciscaucasia leafhopper Metcalfa pruinosa Say are given. Its bioecological peculiarities during the development on the vineyards are described, the trends of harmfulness and spread are identified.

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, Para, 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.

Three new species of the endemic leafhopper genus Devolana are described based from Sierra de Tuxcacuesco (Jalisco), Iguala and Zincauro (Guerrero), Mexico. Overall habitus and genital char...

The leafhopper Yamatotettix flavovittatus Matsumura is the vector of the phytoplasma pathogen that causes white leaf disease in sugarcane crops. This study aimed to identify the bacterial symbionts associated with Y. flavovittatus by amplifying, cloning, and sequencing their 16S rRNA genes. Two types of bacteria were present; one is Candidatus Sulcia muelleri (Bacteroidetes), a well-known ancient primary symbiont found in a diverse range of insects in Auchenorrhyncha suborder. The other is a member of Gammaproteobacteria that differed from all other members deposited in the GenBank database and was therefore named Candidatus Yamatotia cicadellidicola. These bacteria were present throughout the leafhopper life cycle and were found in 100% of the natural host populations examined. Fluorescent in situ hybridization analysis revealed that these bacteria were co-localized in the same bacteriome and present in the full-grown oocyte. Our main finding suggests the Ca. Y. cicadellidicola is a new type of symbiont that co-occurs with Ca. S. muelleri in the leafhopper Y. flavovittatus (Deltocephalinae subfamily).

Pheromones can be used as leafhopper attractants. However, commercial pheromone products, such as the Ingle lure, have certain limitations, including poor persistence in the field. In this study, (E)-2-hexenal, (Z)-3-hexen-1-ol, (Z)-3-hexenyl acetate, (E)-ocimene, linalool, and geraniol were selected and behaviorally tested as potential leafhopper attractants. Y-tube olfactometer tests showed that the C2 formulation was more effective than other formulations. In tea field trials, the number of leafhoppers caught by sticky board traps baited with C2 lures was greater than that caught by treatment. The number of leafhoppers attracted by the C2 lures was greater than that attracted by the commercial Ingle lures. Additionally, the total amount of active C2 components on lures was greater than that of the active components on the lure after 14 days. Thus, the results indicated that the C2 formulation may attract leafhoppers and have a greater persistence than other formulations in tea field.

Among leafhoppers (Hemiptera, Cicadellidae), only Typhlocybinae are known in Mexico to inhabit avocado, an important horticultural crop. In this paper, a potential avocado pest, Dikrellamella Ruppel & DeLong, 1952, is redescribed and illustrated. Additionally, a detailed checklist and a key for all known species of Typhlocybinae associated with avocado trees in Mexico are provided.

Most plant viruses maintain complex interactions with their vector or nonvector insects and can indirectly (via host plants) or directly affect the fitness of insects. However, little is known about the genes involved in the interactions between insects and transmitted or nontransmitted viruses, particularly nontransmitted viruses. Sitobion avenae (Fabricius) is a vector of barley yellow dwarf virus GAV strains (BYDV-GAV), but not a vector of wheat dwarf virus (WDV), which is transmitted by the leafhopper [Psammotettix alienus (Dahlbom)]. In this study, S. avenae was utilized to determine the transcriptomic responses after feeding on wheat infected by each of the two viruses, respectively, using an Illumina Hiseq sequencing platform. The transcriptomic data presented 61,508 genes, of which 854 differentially expressed. Moreover, in addition to sharing 208 genes, the number of differentially expressed genes (DEGs) in S. avenae exposed to BYDV was higher (800) than that when exposed to WDV (262). The DEGs related to the immune system and fitness of S. avenae in response to BYDV-/WDV-infected plants were identified and analyzed using Gene Ontologies (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG), and the number of related DEGs was lower as nonvector than as vector. This study provides the baseline information to further examine molecular mechanisms of how wheat viruses affect S. avenae fitness and immune response either as a vector for BYDV-GAV or as a nonvector for WDV.

Background Empoasca onukii, the tea green leafhopper, is a key pest of tea whose control often requires the extensive use of insecticides. As a predator of the tea green leafhopper, the mite Anystis baccarum is a potential biological control agent worldwide, though little is known about how intercropping cover crops can impact its suppressing effect on E. onukii. Therefore, we conducted a field experiment to investigate how the relationship of the abundance of the predatory mite and its leafhopper prey is influenced by two different cover crops and a manually weeded inter-row treatment as a contrast to naturally growing vegetation in a tea plantation in China. Results The abundance of A. baccarum was significantly higher in tea canopies of intercropped treatments than in canopies over natural ground cover. Litter samples showed higher abundances of A. baccarum when tea was intercropped with Paspalum notatum than with natural ground cover in the first year of treatment. The abundance of E. onukii in tea canopies was higher over the bare ground treatment in the first year but the opposite was observed in the second year. Conclusions Results suggest that the abundance of A. baccarum in a tea plantation is influenced by intercropping and it can affect its leafhopper prey, albeit with varying levels of suppression. For informing biological control and suppression of pests, long-term experiments are needed to investigate the interactions of both pest and predator with cover crop treatments. © 2019 Society of Chemical Industry.

The leafhopper subgenus Pediopsoides (Sispocnis) Anufriev, 1967 is reviewed and the type species is fixed asBythoscopuskogotensisMatsumura, 1912. Six valid species of the subgenus are recognized including two new species described and illustrated here, Pediopsoides (Sispocnis) rectus Li, Li & Dai,sp. nov.and P. (S.) triangulus Li, Li & Dai,sp. nov.from Sichuan Province of Southwestern China. Additionally P. (S.) heterodigitatus Dai & Zhang, 2009 is proposed as a junior synonym of P. (S.) aomians (Kuoh, 1981) based on examination of many specimens. A key to species of the subgenus is also provided for identification.

This paper deals with the leafhopper genusOncopsis(Macropsinae) from Sichuan Province of China, and describes and illustrates two new species,O.konkaensissp. nov.from Minya Konka (Sichuan), andO.moxiensissp. nov.from Moxi Town (Sichuan), and provides a key to males and a geographic distribution map forOncopsisspecies from Sichuan.

Following recent detection of ‘Candidatus Phytoplasma fraxini’, ‘Ca. P. aurantifolia’, ‘Ca. P. solani’ and ‘Ca. P. phoenicium’-related strains in Iranian vineyards, a survey was conducted in 2016–2017 in vineyards located in Qazvin province of Iran. Nested PCR analysis was performed to identify phytoplasma strains in leafhopper species. The overall, less than 5% of grapevine trees shows phytoplasma symptoms and phyto-plasma was detected in all symptomatic samples. Phytoplasma DNA was detected in two leafhopper species. Most leafhopper species in which phytoplasma DNA were detected are recorded to be grass feeders, among which, Stolbur phytoplasma vectors, i.e. Psammotettix alienus (Dahlbom 1851) and Agallia ribauti (Ossian-nilsson, 1938), showed a strong potential ability for ‘Ca. P. solani’ transmission in Qazvin vineyards. The possibility of phytoplasma transmission between leafhoppers and grapevines is discussed.