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BACKGROUND: Vitellogenin (Vg), known as the yolk protein precursor for oocyte development in female insects, can be secreted to plant host from salivary glands of hemipterans, including rice leafhopper Recilia dorsalis. The aim of this study was to investigate the function of salivary‐secreted Vg of R. dorsalis (RdVg) in rice host. We propose that RdVg possibly regulates the rice defense against insects, benefiting R. dorsalis feeding. RESULTS: RdVg was released into rice phloem along with saliva during R. dorsalis feeding. Knocking down RdVg increased the level of H2O2 and improved H2O2 metabolism in rice plants, making it difficult for R. dorsalis to feed. The transient expression or overexpression of the lipoprotein N‐terminal domain of RdVg (RdVg2) significantly reduced hydrogen peroxide (H2O2) metabolism in plants. This suggests that salivary‐secreted RdVg acts as an effector suppressing the H2O2 burst in rice plants, and RdVg2 is the key domain. RdVg2 could interact with rice sulfite oxidase (OsSO), which catalyzes the oxidation of SO32− and produces H2O2. Exposure of rice plants to R. dorsalis, overexpression of RdVg2 or knocking out OsSO reduced OsSO accumulation and SO32− oxidation, benefiting R. dorsalis feeding. However overexpression of OsSO increased SO32− oxidation and H2O2 metabolism, inhibiting R. dorsalis feeding. CONCLUSION: RdVg inhibits H2O2 generation via suppressing OsSO accumulation, ultimately benefiting R. dorsalis feeding. These findings identify RdVg as an effector that suppresses plant defense to insects, and provide insights into the function of salivary‐secreted Vg in other Hemiptera insects. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this article a deterministic model for Maize Streak Virus Disease (MSVD) using a fractional-order differential equation with the Atangana-Baleanu Caputo-type operator is developed. Focusing on the role of host-to-host transmission, the it is shown that the presence and stability of equilibria depends on maize field carrying capacity and half-saturation constant of susceptible maize. The MSVD-free equilibrium is globally asymptotically stable when the basic reproduction number is below unity. Local stability conditions for endemic equilibria are established using Lyapunov second technique and Routh-Hurwitz criteria. Matrix-based formulae are also presented for determining bifurcation and it is shown that the model exhibits forward bifurcation. Sensitivity analysis reveals the significant impact of the probability of infection between hosts on MSVD spread. A two-point Lagrange interpolation polynomial is developed for numerical solutions of the model, enabling exploration of theoretical findings and assessment of how epidemiological factors influence MSVD propagation. The paper contributes a comprehensive understanding of the disease's behavior under various conditions. [ABSTRACT FROM AUTHOR]

Fulgoraecia melanoleuca (Fletcher) is an important ecto-parasitoid of Pyrilla perpusilla (Walker) nymphs and adults. The study aimed to standardize the augmentative releases of F. melanoleuca life stages (eggs and cocoons) for eco-friendly management of P. perpusilla in sugarcane crop. The releases of F. melanoleuca cocoons (2000, 4000, and 6000 cocoons ha−1) and eggs (0.2, 0.4, and 0.6 million eggs ha−1) were compared with chemical control (chlorpyriphos 20 EC @1500 ml ha−1) and untreated control. Two releases were carried out at monthly interval during 1st week of August and 1st week of September. The pyrilla population decreased progressively with increase in released cocoons (2000, 4000, and 6000 ha−1) and eggs (0.2, 0.4, and 0.6 million ha−1). The augmentative releases play a noteworthy role in increasing the parasitoid count (egg masses, cocoons and adults) in the released plots. Overall, the parasitism (nymph + adult) increased with increase in doses and it was significantly higher when parasitoids were released at higher doses, i.e. 0.6 million eggs ha−1 (52.80%) and 6000 cocoons ha−1 (50.60%). However, chlorpyriphos 20 EC (1500 ml ha−1) was found to be highly detrimental to the parasitoid as no parasitism was observed in insecticide-sprayed plots. In conclusion, two releases of F. melanoleuca parasitoid (0.6 million eggs ha−1 or 6000 cocoons ha−1) at monthly interval (1st week of August and 1st week of September) proved better due to higher parasitism rate, increase in parasitoid population, and reduction in pyrilla population and also rendered higher cane yield and better juice quality. The findings will help in the eco-friendly management of P. perpusilla in sugarcane. [ABSTRACT FROM AUTHOR]

To elucidate phylogenetic relationships within the leafhopper's subfamily Megophthalminae (Hemiptera: Cicadellidae), mitogenomes of 12 species of the subfamily were sequenced and assembled. These were added to the mitogenomes of the eight other species that are currently available. Mitogenome size ranged from 15,193 bp in Onukigallia onukii (Matsumura, 1912) to 15,986 bp in Multinervis guangxiensis (Li and Li, 2013), they all contained 37 genes, and gene order was similar to that in other leafhoppers. Nucleotide composition analysis showed that the AT content was higher than that of GC, and the protein-coding genes usually ended with A/T at the 3rd codon position. The K a/ K s ratio showed that the CYTB gene has the slowest evolutionary rate, while ND4 is the gene with the fastest evolutionary rate. Relative synonymous codon usage analysis revealed the most frequently used codon was UUA (L), followed by CGA (R), and the least frequently used codon was CCG (P). Parity plot and neutrality plot analyses showed that the codon usage bias of mitochondrial genes was influenced by natural selection and mutation pressure. However, natural selection plays a major role, while the effect of mutation pressure was small. Effective number of codons values were 40.15–49.17, which represented relatively low codon bias. Phylogenetic analyses based on three datasets (AA, 13PCG, 13PCG_2rRNA) using two methods (maximum likelihood and Bayesian inference). In the obtained topology, the Megophthalminae species were clustered into a monophyletic group. In conclusion, our results clarify structural modules of the mitochondrial genes and confirm the monophyly of Megophthalminae within Cicadellidae. [ABSTRACT FROM AUTHOR]

In this article a deterministic model for Maize Streak Virus Disease (MSVD) using a fractional-order differential equation with the Atangana-Baleanu Caputo-type operator is developed. Focusing on the role of host-to-host transmission, the it is shown that the presence and stability of equilibria depends on maize field carrying capacity and half-saturation constant of susceptible maize. The MSVD-free equilibrium is globally asymptotically stable when the basic reproduction number is below unity. Local stability conditions for endemic equilibria are established using Lyapunov second technique and Routh-Hurwitz criteria. Matrix-based formulae are also presented for determining bifurcation and it is shown that the model exhibits forward bifurcation. Sensitivity analysis reveals the significant impact of the probability of infection between hosts on MSVD spread. A two-point Lagrange interpolation polynomial is developed for numerical solutions of the model, enabling exploration of theoretical findings and assessment of how epidemiological factors influence MSVD propagation. The paper contributes a comprehensive understanding of the disease's behavior under various conditions.

A total of 151 genotypes of durum and bread wheat exhibiting symptoms of stunting and bushy growth, leaf yellowing, and drying of clumps were recorded at ICAR-IARI Regional Station, Indore, Madhya Pradesh, India from 2016 to 2018. The disease incidence was recorded more in durum wheat genotypes as compared to bread wheat genotypes. The presence of any virus, bacterial, and fungal pathogens was ruled out by applying cultural growth and electron microscopy. However, association of phytoplasmas presence was confirmed in 142 (out of 151) durum and bread wheat genotypes by employing PCR primer pairs of 16S rRNA, leuS and secA genes. The sequence analysis of all the genes and in silico RFLP analysis of 16S rDNA sequences of wheat phytoplasma strains identified them as rice yellow dwarf group (16SrXI-B) and Bermuda grass white leaf group (16SrXIV-A). Two symptomatic weed species (Parthenium hysterophorus and Cleome gynandra) tested positive for 16SrXI-B phytoplasma subgroup and four weed species (Cynodon dactylon, Digitaria sanguinalis, Euphorbia hirta and Rhynchosia minima) for 16SrXIV-A phytoplasma subgroup growing in and around wheat fields. Six hopper species identified from symptomatic wheat fields were also analyzed for phytoplasma presence. Three hopper species viz., Sogatella furcifera, Balclutha rubrostriata, and Exitianus indicus were tested positive to phytoplasmas in 16SrXIV group, while Sogatella kolophon, Cofana unimaculata, and Maiestas sp. tested positive to 16SrXI group of phytoplasmas in nested PCR assays. Transmission assays revealed that S. furcifera and B. rubrostriata successfully transmitted the 16SrXIV-A strain from infected wheat to healthy wheat plants; however, C. unimaculata was able to transmit 16SrXI-B subgroup from infected wheat to healthy wheat plants under glasshouse conditions. A variation in phytoplasma associated disease incidence was recorded on wheat genotypes in different years and was also found positively correlated with temperature, humidity, and hopper population. The identification of similar phytoplasma strains (16SrXI and 16SrXIV group) from wheat, weeds, and hoppers indicated potential risk of transmission of these strains to wheat genotypes and other agricultural crops, which needs further investigations on epidemiological aspects. [ABSTRACT FROM AUTHOR]

Simple Summary: The corn leafhopper, an invasive insect and vector of corn stunt spiroplasma, has been reported in multiple counties in Oklahoma. Corn stunt spiroplasma-infected corn leafhoppers were also confirmed in the state. The corn leafhopper, Dalbulus maidis (DeLong and Wolcott) (Hemiptera: Cicadellidae), is an invasive insect that can cause damage to maize (Zea mays L.) in two ways: by direct feeding and the transmission of several plant pathogens. Dalbulus maidis is an invasive and serious economic pest of maize that has spread from its center of origin in Mexico to the southernmost parts of the United States. Prior to 2024, corn leafhoppers had not been documented in Oklahoma, and their spread northward toward the United States corn belt is of significant concern. Here, we provide the first reports of the insect in maize in several Oklahoma counties. Insect specimens were collected at various commercial and experimental field sites by Oklahoma State University research and extension personnel. The identity of the insect species was validated through morphological and molecular taxonomy. The presence records for the corn leafhopper presented here provide valuable information for future monitoring and management efforts of this economically important pest and disease. [ABSTRACT FROM AUTHOR]

Batracomorphus is the most diverse and widely distributed genus of Iassinae. Nevertheless, there has been no systematic analysis of the genome structure and phylogenetic relationships of the genus. To determine the characteristics of the mitogenomes of Batracomorphus species as well as the phylogenetic relationships between them, we sequenced and compared the mitogenomes of 11 representative Batracomorphus species. The results revealed that the mitogenomes of the 11 Batracomorphus species exhibited highly similar gene and nucleotide composition, and codon usage compared with other reported mitogenomes of Iassinae. Of these 11 species, we found that the mitogenomes of four species were rearranged in the region from trnI-trnQ-trnM to trnQ-trnI-trnM, whereas the remaining species presented a typical gene order. The topologies of six phylogenetic trees were in agreement. Eurymelinae consistently formed paraphyletic groups. Ledrinae and Evacanthinae formed sister taxa within the same clade. Similarly, Typhlocybinae and Mileewinae consistently clustered together. All phylogenetic trees supported the monophyly of Iassinae, indicating its evolutionary distinctiveness while also revealing its sister relationship with Coelidiinae. Notably, the nodes for all species of the genus Batracomorphus were well supported and these taxa clustered into a large branch that indicated monophyly. Within this large branch, four Batracomorphus species with a gene rearrangement (trnQ-trnI-trnM) exhibited distinctive clustering, which divided the large branch into three minor branches. These findings expand our understanding of the taxonomy, evolution, genetics, and systematics of the genus Batracomorphus and broader Iassinae groups. [ABSTRACT FROM AUTHOR]

Summary: 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 H2O2 during insect‐to‐plant virus transmission.We found that the interaction of OsNCA1 with RdCAT activated its enzymatic activity to decompose H2O2 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 H2O2 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 H2O2, 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 H2O2 burst during insect feeding, thereby facilitating viral transmission. [ABSTRACT FROM AUTHOR]

The recent surge in sweet potato (Ipomoea batatas) cultivation in Europe prompted an investigation into associated entomofauna within Portugal's southwestern region, known for its longstanding sweet potato production. This study aimed to assess entomofauna associated with this culture. Insect sampling was conducted by leaf and sweep net across three regional sites during 2018 and 2019 revealing the presence of Empoasca fabalis. Histological examination of sweet potato leaves affected by E. fabalis feeding unveiled significant damage, including the emergence of whitish spots (termed “stipples”) and subsequent necrotic spots. Comparative analysis between infested and undamaged control leaves revealed significant damage, involving mesophyll cell content deprivation and cellular disruption. This study describes, for the first time, the histological nature of the necrotic damage and suggests that E. fabalis primarily acts as a stippler on sweet potatoes, mainly targeting mesophyll cells with limited consumption of vascular tissue. The invasive behaviour and wide host range of E. fabalis pose a threat to sweet potato cultivation. These findings emphasize the need for monitoring to address the potential impact of E. fabalis on Europe’s agricultural ecosystem and native vegetation. In addition, six other Auchenorrhyncha species were identified during this study, including four crucial vectors of plant diseases: Laodelphax striatellus, Psammotettix alienus, Anaceratagallia glabra, Austroagallia sinuata, together with Empoasca solani and E. alsiosa. These results emphasise the importance of managing these insects in sweet potato cultivation. [ABSTRACT FROM AUTHOR]

Defence mechanisms in plants have been naturally or artificially selected to cope with virus infection and/or insect colonization. This creates a range of host susceptibility to viruses and/or insects that can impact the epidemiology of insect‐borne viral diseases. Wheat dwarf disease (WDD), one of the most important viral diseases on small‐grain cereals, is caused by wheat dwarf virus (WDV), which is transmitted by the leafhopper Psammotettix alienus. In the current context of the unavailability of either WDV‐resistant/tolerant wheat cultivars or effective methods to control WDD in French cereal fields, the accurate characterization of WDV‐susceptible genotypes must be considered to improve management strategies against this viral disease. In this study, the impact of 12 wheat cultivars on epidemiological parameters related to the introduction (host selection and virus infection) and spread (insect performance and virus transmission) of WDD was evaluated. Results showed no differences between the tested cultivars for host selection made by P. alienus, whereas four tested cultivars (Complice, Filon, Hyking and Nemo) reduced survival and/or fecundity of the leafhopper. Characterization of virus–host interactions highlights the lower host and source quality of cv. Filon for WDV. Finally, multivariate analyses allowed the identification of cvs Filon, Boregar, Solindo CS, Complice and Hyking as less suitable hosts for WDV and/or P. alienus, suggesting that these cultivars could present interesting genetic resource(s) that should be considered for future breeding programmes against WDD. [ABSTRACT FROM AUTHOR]

Cicadellidae (leafhoppers) may be the most diverse and abundant insect herbivores in terrestrial ecosystems worldwide, with more than 23,000 described species in 20 extant subfamilies. Although prior studies have supported the monophyly of most recognized subfamilies, relationships among these groups remain inconsistently resolved and previous molecular phylogenies have failed to support the monophyly of a few subfamilies. To help address this deficiency, we combined 24 new complete mitogenomes representing 6 previously unsequenced subfamilies and 13 tribes with previously available data to create a dataset of 79 cicadellid taxa representing 16 subfamilies for phylogenetic analysis. The new analyses confirm that leafhopper mitochondrial genomes are highly conservative in overall structure, with only a few rare rearrangements of tRNAs. All phylogenetic analyses consistently supported the monophyly of previously recognized cicadellid tribes for which more than 1 representative was included and all of the included subfamilies were also consistently recovered as monophyletic with the exception of Aphrodinae and Eurymelinae. Bayesian inference and Maximum Likelihood analyses with site-homogeneous models are only slightly affected by nucleotide compositional heterogeneity and yield more stable phylogenetic relationships of family-group taxa than analyses with a heterogeneous-site mixture model using PhyloBayes. Molecular divergence time estimates indicate that the main lineages of Cicadellidae, most corresponding to recognized subfamilies, diverged during the Cretaceous period (93–121 Mya). [ABSTRACT FROM AUTHOR]

Leafhoppers are economically important pests and may serve as vectors for pathogenic viruses that cause substantial crop damage. In this study, using deep transcriptome sequencing, we identified three novel viruses within the order Mononegavirales, including two viruses belonging to the family Rhabdoviridae and one to the family Lispiviridae. The complete genome sequences were obtained via the rapid amplification of cDNA ends and tentatively named Recilia dorsalis rhabdovirus 1 (RdRV1, 14,251 nucleotides, nt), Nephotettix virescens rhabdovirus 1 (NvRV1, 13,726 nt), and Nephotettix virescens lispivirus 1 (NvLV1, 14,055 nt). The results of a phylogenetic analysis and sequence identity comparison suggest that RdRV1 and NvRV1 represent novel species within the family Rhabdoviridae, while NvLV1 is a new virus belonging to the family Lispiviridae. As negative-sense single-strand RNA viruses, RdRV1 and NvRV1 contain the conserved transcription termination signal and intergenic trinucleotides in the non-transcribed region. Intergenomic sequence and transcriptome profile analyses suggested that all these genes were co-transcriptionally expressed in these viral genomes, facilitated by specific intergenic trinucleotides and putative transcription initiation sequences. [ABSTRACT FROM AUTHOR]

The bacterial genus Wolbachia induces reproductive abnormalities in its insect host, including cytoplasmic incompatibility (CI), which causes embryonic death in the crossing of infected males and uninfected females. Hence, Wolbachia-based strategies are employed to control insect pests. However, Wolbachia does not naturally infect Matsumuratettix hiroglyphicus (Matsumura), the main vector of the phytoplasma causing the sugarcane white leaf (SCWL) disease. In this study, the wYfla Wolbachia strain, which induces strong CI in its original host, was microinjected into nymphs of M. hiroglyphicus. Molecular detection revealed that Wolbachia was successfully transinfected into the recipient host, with an infection frequency of 55–80% in up to eight generations after transinfection. Wolbachia exhibited no significant detrimental effects on the developmental time of the immature stages, adult emergences, and female longevity, whereas the lifespan of transinfected males was decreased. Reciprocal crossing revealed that Wolbachia infection did not affect the number of eggs laid per female. However, the hatching rate produced by the pairs between the transinfected males and naturally uninfected females significantly decreased. The evidence of Wolbachia transmitted through the generations tested and partial CI occurrence in transinfected M. hiroglyphicus highlights the possibility of the future development of Wolbachia-based strategies for controlling the vector of SCWL. [ABSTRACT FROM AUTHOR]

Soybean pests are one of the major factors limiting yield improvement. With the expansion of area and changes in cropping patterns, a number of new pests have been identified in the main soybean production areas of China. The common brown leafhopper, Orosius orientalis, is a new pest associated with soybean stay-green virus that has been discovered on cultivated soybean crop in the Yellow-Huai-hai region of China in recent years. The polyphagous insect has a wide feeding range and infests a variety of important grain and cash crops. This paper presents the basic information, geographical distribution, hosts, damage characteristics, plant virus transmission, occurrence patterns, and prevention and control measures O. orientalis. This review also provides insights into integrated prevention and control of the genus Orosius as an insect vector.

The leafhopper genus Parabolopona of Korea is reviewed. Two species of the genus are reported from Korea: Parabolopona ishihari Webb, 1981, and Parabolopona cygnea Cai & Shen, 1999. We provide morphological information on the species, a key to the Korean Parabolopona species, and a checklist of the world.

Three new species of the genus Atkinsoniella (Hemiptera: Cicadellidae: Cicadellinae), A. chongqingana Jiang & Yang, A. likuni Jiang & Yang and A. biostiolum Jiang & Yang, sp. nov., collected from southwestern China, are described and illustrated. The two new species, A. chongqingana Jiang & Yang, sp. nov. and A. likuni Jiang & Yang, sp. nov., are similar to A. nigrominiatula (Jacobi, 1944), A. latior Young, 1986, A. limba Kuoh, 1991, A. dormana Li, 1992, A. divaricata Yang, Meng & Li, 2017, A. peaka Yang, Meng & Li, 2017, and A. zizhongi Jiang & Yang, 2022 in appearances, but can be distinguished from these species by the characteristic of aedeagus, paraphysis, and pygofer. Atkinsonella biostiolum Jiang & Yang, sp. nov. can be distinguished from all the known Atkinsoniella species by its special color and markings, as well as males having one ostiole in the center of the base of each subgenital plate. A key to Atkinsoniella species from China is provided. [ABSTRACT FROM AUTHOR]

Invasive insects threaten ecosystem stability, public health, and food security. Documenting newly invasive species and understanding how they reach into new territories, establish populations, and interact with other species remain vitally important. Here, we report on the invasion of the South American leafhopper, Curtara insularis into Africa, where it has established populations in Ghana, encroaching inland at least 350 km off the coast. Importantly, 80% of the specimens collected were intercepted between 160 and 190 m above ground. Further, the fraction of this species among all insects collected was also higher at altitude, demonstrating its propensity to engage in high-altitude windborne dispersal. Its aerial densities at altitude translate into millions of migrants/km over a year, representing massive propagule pressure. Given the predominant south-westerly winds, these sightings suggest an introduction of C. insularis into at least one of the Gulf of Guinea ports. To assess the contribution of windborne dispersal to its spread in a new territory, we examine records of C. insularis range-expansion in the USA. Reported first in 2004 from central Florida, it reached north Florida (Panhandle) by 2008–2011 and subsequently spread across the southeastern and south-central US. Its expansion fits a "diffusion-like" process with 200—300 km long "annual displacement steps"—a pattern consistent with autonomous dispersal rather than vehicular transport. Most "steps" are consistent with common wind trajectories from the nearest documented population, assuming 2—8 hours of wind-assisted flight at altitude. Curtara insularis has been intercepted at US ports and on trucks. Thus, it uses multiple dispersal modalities, yet its rapid overland spread is better explained by its massive propagule pressure linked with its high-altitude windborne dispersal. We propose that high-altitude windborne dispersal is common yet under-appreciated in invasive insect species. [ABSTRACT FROM AUTHOR]

Whitefly, Bemisia tabaci (Gennadius), and leafhopper, Amrasca biguttulla biguttulla, Ishida, are the major biotic constraints in cultivation of okra, causing considerable economic damage. The present study aims to evaluate the laboratory and field efficacy of butenolide insecticide, flupyradifurone 200 SL against these key sucking pests, its phytotoxicity, safety to natural enemies as well as pollinators and cost-efficiency in okra. Dose probit mortality assays indicated flupyradifurone to be the most toxic and thiamethoxam least toxic to leafhopper and whitefly. Based on the LC50 values for whitefly and leafhopper, flupyradifurone exhibited 11.07 and 2.98-fold difference, respectively, when compared to thiamethoxam. Laboratory bioassays confirmed that the maximum dose of flupyradifurone (250 g a.i. ha−1) had a high level of toxicity to whitefly adults and leafhopper nymphs. Of the three field rates (150, 200, 250 g a.i. ha−1) of flupyradifurone evaluated under open field conditions, application at 250 g a.i. ha−1 was most effective for the control of whitefly and leafhopper population with a high marketable fruit yield in okra. Flupyradifurone reduced the population of whitefly by 71.80 & 76.68 per cent and leafhopper by 82.19 and 80.21 per cent during first and second season, respectively, as compared to untreated control. Furthermore, it was superior and more economical, giving the highest benefit: cost ratio (2.77) than other test insecticides included for comparison. Flupyradifurone application showed no phytotoxic symptoms on the okra crop. Additionally, it was found to be safer to natural enemies i.e. spiders and rove beetles that are prevalent in the okra ecosystem. The Kaplan–Meier survival analysis showed that flupyradifurone was apparently less toxic to honey bees in short-term and long-term exposure assays. These findings will aid in utilizing the flupyradifurone in insecticide window spray schedules and IPM programs for the management of sucking pests in okra. [ABSTRACT FROM AUTHOR]

The leafhopper Matsumuratettix hiroglyphicus is the vector of the phytoplasma associated with sugarcane white leaf disease in Asia. However, highly virulent strains of entomopathogenic fungi to control this vector are lacking. To select effective fungal strains, serial passaging through the leafhopper and the phenotypic properties and virulence of four strains were evaluated and compared to those of their initial stock. The influence of fungal passaging through the insect varied according to the fungal genus, strain, and passage number. The third and fifth passages of all fungal strains improved the examined parameters and showed virulence enhancement compared to those of the initial stock; however, a decrease in the parameters was observed after the seventh passage. The fifth passage of Beauveria bassiana SUTTU01 exhibited phenotypic changes resulting in significantly higher pathogenicity (80% mortality) than its corresponding initial stock. When the effect of fungal treatment on the transmission capacity of M. hiroglyphicus was tested, no significant difference was found in white leaf disease-related phytoplasma infection between untreated and fungi-treated leafhoppers. However, the fifth passage of B. bassiana SUTTU01-treated leafhoppers exhibited the lowest titer of the phytoplasma, resulting in a reduced transmission rate and fewer infected plants. This is the first report on the influence of B. bassiana on leafhopper vector capacity. The results obtained constitute a basis for future research on effective fungal strains able to reduce the phytoplasma transmission rate of this leafhopper vector. [ABSTRACT FROM AUTHOR]

Batracomorphus is the most diverse and widely distributed genus of Iassinae. Nevertheless, there has been no systematic analysis of the genome structure and phylogenetic relationships of the genus. To determine the characteristics of the mitogenomes of Batracomorphus species as well as the phylogenetic relationships between them, we sequenced and compared the mitogenomes of 11 representative Batracomorphus species. The results revealed that the mitogenomes of the 11 Batracomorphus species exhibited highly similar gene and nucleotide composition, and codon usage compared with other reported mitogenomes of Iassinae. Of these 11 species, we found that the mitogenomes of four species were rearranged in the region from trnI-trnQ-trnM to trnQ-trnI-trnM, whereas the remaining species presented a typical gene order. The topologies of six phylogenetic trees were in agreement. Eurymelinae consistently formed paraphyletic groups. Ledrinae and Evacanthinae formed sister taxa within the same clade. Similarly, Typhlocybinae and Mileewinae consistently clustered together. All phylogenetic trees supported the monophyly of Iassinae, indicating its evolutionary distinctiveness while also revealing its sister relationship with Coelidiinae. Notably, the nodes for all species of the genus Batracomorphus were well supported and these taxa clustered into a large branch that indicated monophyly. Within this large branch, four Batracomorphus species with a gene rearrangement (trnQ-trnI-trnM) exhibited distinctive clustering, which divided the large branch into three minor branches. These findings expand our understanding of the taxonomy, evolution, genetics, and systematics of the genus Batracomorphus and broader Iassinae groups.

The present study is focused on the species belonging to the genus Maiestas Distant, 1917 (Hemiptera: Cicadellidae: Deltocephalinae, Deltocephalini) in Iran, based on some specimens collected during 2016 to 2019 from Southeast Iran and species that have been previously reported: M. horvathi (Then, 1896), M. pruthii (Metcalf, 1967), M. schmidtgeni (Wagner, 1939), and M. trifasciata (Lindberg, 1954). M. pruthii, previously known from the Oriental region (India and Pakistan), is recorded for the first time in the Palaearctic region from Southeast Iran and M. horvathi is a new record for the fauna of Sistan and Baluchestan Province. An identification key and distribution maps for the Iranian Maiestas species are provided.

In nature, leafhoppers cover their body surfaces with brochosomes as a protective coating. These leafhopper-produced brochosomes are hollow, buckyball-shaped, nanoscopic spheroids with through-holes distributed across their surfaces, representing a class of deployable optical materials that are rare in nature. Despite their discovery in the 1950s, it remains unknown why the sizes of brochosomes and their through-holes consistently fall within the range of hundreds of nanometers across different leafhopper species. Here, we demonstrate that the hierarchical geometries of brochosomes are engineered within a narrow size range with through-hole architecture to significantly reduce light reflection. By utilizing two-photon polymerization three-dimensional printing to fabricate high-fidelity synthetic brochosomes, we investigated the optical form-to-function relationship of brochosomes. Our results show that the diameters of brochosomes are engineered within a specific size range to maximize broadband light scattering, while the secondary through-holes are designed to function as short-wavelength, low-pass filters, further reducing light reflection. These synergistic effects enable brochosomes to achieve a substantial reduction in specular reflection, by up to approximately 80 to 94%, across a broadband wavelength range. Importantly, brochosomes represent a biological example demonstrating short-wavelength, low-pass filter functionality. Furthermore, our results indicate that the geometries of natural brochosomes may have evolved to effectively reduce reflection from ultraviolet to visible light, thereby enabling leafhoppers to evade predators whose vision spectrum encompasses both ultraviolet and visible light. Our findings offer key design insights into a class of deployable bioinspired optical materials with potential applications in omnidirectional antireflection coatings, optical encryption, and multispectral camouflage. [ABSTRACT FROM AUTHOR]

Here, we report a novel wheat-infecting marafivirus, tentatively named "Triticum aestivum marafivirus" (TaMRV). The full-length genome sequence of TaMRV comprises 6,437 nucleotides, excluding the poly(A) tail. Pairwise sequence comparisons and phylogenetic analysis revealed that TaMRV may represent a novel species within the genus Marafivirus in the family Tymoviridae. We also observed a mass of isometric particles with a diameter of about 30 nm in ultrathin sections of infected wheat leaf tissue. In addition, the leafhopper Psammotettix alienus was identified as a vector for this virus. This is the first report of the occurrence of a wheat-infecting marafivirus. [ABSTRACT FROM AUTHOR]

The present study is focused on the species belonging to the genus Maiestas Distant, 1917 (Hemiptera: Cicadellidae: Deltocephalinae, Deltocephalini) in Iran, based on some specimens collected during 2016 to 2019 from Southeast Iran and species that have been previously reported: M horvathi (Then, 1896), M pruthii (Metcalf, 1967), M schmidtgeni (Wagner, 1939), and M. trifasciata (Lindberg, 1954). M. pruthii, previously known from the Oriental region (India and Pakistan), is recorded for the first time in the Palaearctic region from Southeast Iran and M. horvathi is a new record for the fauna of Sistan and Baluchestan Province. An identification key and distribution maps for the Iranian Maiestas species are provided. [ABSTRACT FROM AUTHOR]

Leafhoppers comprise over 20,000 plant‐sap feeding species, many of which are important agricultural pests. Most species rely on two ancestral bacterial symbionts, Sulcia and Nasuia, for essential nutrition lacking in their phloem and xylem plant sap diets. To understand how pest leafhopper genomes evolve and are shaped by microbial symbioses, we completed a chromosomal‐level assembly of the aster leafhopper's genome (ALF; Macrosteles quadrilineatus). We compared ALF's genome to three other pest leafhoppers, Nephotettix cincticeps, Homalodisca vitripennis, and Empoasca onukii, which have distinct ecologies and symbiotic relationships. Despite diverging ~155 million years ago, leafhoppers have high levels of chromosomal synteny and gene family conservation. Conserved genes include those involved in plant chemical detoxification, resistance to various insecticides, and defence against environmental stress. Positive selection acting upon these genes further points to ongoing adaptive evolution in response to agricultural environments. In relation to leafhoppers' general dependence on symbionts, species that retain the ancestral symbiont, Sulcia, displayed gene enrichment of metabolic processes in their genomes. Leafhoppers with both Sulcia and its ancient partner, Nasuia, showed genomic enrichment in genes related to microbial population regulation and immune responses. Finally, horizontally transferred genes (HTGs) associated with symbiont support of Sulcia and Nasuia are only observed in leafhoppers that maintain symbionts. In contrast, HTGs involved in non‐symbiotic functions are conserved across all species. The high‐quality ALF genome provides deep insights into how host ecology and symbioses shape genome evolution and a wealth of genetic resources for pest control targets. [ABSTRACT FROM AUTHOR]

Field trials were conducted over two seasons in 2019-20 and 2020-21 at experimental fields near Shri Venkateshwara University, Amroha, U.P. The present study on the efficacy of a new group of insecticides against insect pests of potato crop was designed in a randomised block design with nine treatments replicated thrice. The treatments included (T1): Thiamethoxam 25 WG @ 150 g/ha (Actra), (T2): Imidacloprid 17.8 SL @ 150 ml/ha (Confidor), (T3): Flonicamid 50% WG @ 150 ml/ha (Ulala), (T4): Abamectin 1.9% EC @ 125 ml/ha (Abacin), (T5): Indoxacarb 14.5% SC @ 250 ml/ha (Avaunt), (T6): Flubendiamide 39.35% SC @ 125 ml/ha (Fame), (T7): Spinosad 45% SC @ 150 ml/ha (Tracer), (T8): Chlorantraniliprole 18.5% SC @ 150 ml/ha (Coragen) and (T9): Control (Water spray). Totally, three sprays were taken up. The first spray was given on the 25th day after emergence and the second and third sprays were made at 40 and 55 days after emergence, respectively. The treatments with three sprays of Thiamethoxam 25 WG @ 150 g/ha, Imidacloprid 17.8 SL @ 150 ml/ha and Flonicamid 50% WG @ 150 ml/ha were effective in reducing the population of aphids, whiteflies and leafhoppers in potato. The next best treatments in this respect were Abamectin 1.9% EC @ 125 ml/ha and Flubendiamide 39.35% SC @ 125 ml/ha. [ABSTRACT FROM AUTHOR]

The experimental trials were conducted at Agronomy farm S. K. N. College of Agriculture, Jobner (Rajasthan) during kharif 2019 to identify the infestation of major insect pests of sesame (leaf roller and capsule borer, leafhopper and whitefly). Ten sesame varieties were screened to know their response on the basis of morphometric and biochemical characters. The morphological characters of plant showed that the variety RT-346, which had more number of leaves, branches, capsules per plant and number of trichomes per mm² was found least susceptible for the leaf roller and capsule borer, leafhopper and whitefly population. Whereas the variety RT-46 was found to be most susceptible, which had less trichomes than the variety RT-346. Thus, the morphometric characters like number of leaves per plant, number of branches per plant, number of capsules per plant and trichome density per mm², showed a negative correlation with the mean population of leaf roller and capsule borer, leafhopper and whitefly population in sesame. The total phenols had a negative and significant correlation, while free amino acids, total soluble sugars, protein content and chlorophyll had positive and significant correlation with leaf roller and capsule borer, leafhopper and whitefly population. [ABSTRACT FROM AUTHOR]

Aster leafhopper (Hemiptera: Cicadellidae: Macrosteles quadrilineatus Forbes) is a polyphagous insect species that migrates into the upper Midwest of the United States and the Western Canadian Prairies. Populations of this insect are associated with the transmission of a plant pathogen (Candidatus Phytoplasma asteris, 16SrI) to several annual crops and perennial plant species. Previous studies suggest that aster leafhoppers can sometimes prefer less suitable hosts for their development and survival, yet it is unclear if this lower performance on certain plant species is associated with reduced or impaired probing behaviors due to characteristics of the plants. To characterize the probing behaviors of aster leafhoppers, direct current electropenetrography recordings of male and female adults on barley (Polaes: Poaceae: Hordeum vulgare L.) were combined with plant histology, allowing the identification of nine waveforms and their proposed biological meanings. For each waveform, the number of waveform events per insect (NWEI), the waveform duration per insect (WDI), the waveform duration per event per insect (WDEI), and the percentage of recording time were calculated and statistically compared between sexes. Male and female aster leafhoppers exhibited similar behavioral responses for most of these variables, except for the NWEI for waveforms associated with nonprobing activities and the pathway phase. In these cases, male aster leafhoppers exhibited a higher number of events than females. Comparison of the proposed waveforms in this study with previous work on other hemipteran species provided additional support to the interpretation of the biological activities associated with each waveform. [ABSTRACT FROM AUTHOR]

The dikraneurine leafhopper genus Anaka is reviewed based on a comparative morphological study. Five new species, Anaka auricula sp. nov., Anaka cruciata sp. nov., Anaka curvata sp. nov., Anaka rosacea sp. nov., and Anaka spiralis sp. nov. from China are described and illustrated in detail. Additionally, a key to known Anaka species is provided along with a checklist of all species and their distributions. [ABSTRACT FROM AUTHOR]

Brochosomes, which are nanoscopic buckyball-shaped granules produced by leafhoppers, are one of the most intricate structures discovered in nature. Various functions of brochosomes have been proposed but only a few have been experimentally validated due to the challenge of fabricating their synthetic counterparts. Advancements in micro- and nanofabrication have recently led to the emergence of synthetic brochosomes, opening up new possibilities for innovative applications. This review explores the early discovery of natural brochosomes and their geometrical features, followed by the recent progress in fabricating synthetic brochosomes and their applications. Perspectives on future applications and challenges in the scalable manufacturing of synthetic brochosomes are discussed. [ABSTRACT FROM AUTHOR]

Abstract Background The phylogenetic position and classification of Athysanini are poorly defined, as it includes a large group of polyphyletic genera that have historically been assigned to it mainly because they still exhibit the most typical deltocephaline genitalic and external body characters but lack the distinctive characteristics that other tribes possess. The bamboo-feeding leafhopper genus Abrus belong to the tribe Athysanini of subfamily Deltocephalinae, which currently comprises 19 valid described species, and are limited to the Oriental and Palaearctic regions in China. Although the taxonomy of Abrus are well updated, the references on comparative mitogenomic analyses of Abrus species are only known for a single species. In this study, we sequenced and analyzed the complete mitochondrial genomes (mitogenomes) of Abrus daozhenensis Chen, Yang & Li, 2012 (16,391bp) and A. yunshanensis Chen, Yang & Li, 2012 (15,768bp) (Athysanini), and compared with published mitogenome sequence of A. expansivus Xing & Li, 2014 (15,904bp). Results These Abrus species shared highly conserved mitogenomes with similar gene order to that of the putative ancestral insect with 37 typical genes and a non-coding A + T-rich region. The nucleotide composition of these genomes is highly biased toward A + T nucleotides (76.2%, 76.3%, and 74.7%), AT-skews (0.091 to 0.095, and 0.095), negative GC-skews (− 0.138, − 0.161, and − 0.138), and codon usage. All 22 tRNA genes had typical cloverleaf secondary structures, except for trnS1 (AGN) which lacks the dihydrouridine arm, and distinctively trnG in the mitogenome of A. expansivus lacks the TψC arm. Phylogenetic analyses based on 13 PCGs, 2 rRNA genes, and 22 tRNA genes consistently recovered the monophyletic Opsiini, Penthimiini, Selenocephalini, Scaphoideini, and Athysanini (except Watanabella graminea, previously sequenced species as Chlorotettix nigromaculatus) based on limited available mitogenome sequence data of 37 species. Conclusion At present, Abrus belongs to the tribe Athysanini based on both morphological and molecular datasets, which is strongly supported in present phylogenetic analyses in both BI and ML methods using the six concatenated datasets: amino acid sequences and nucleotides from different combinations of protein-coding genes (PCGs), ribosomal RNA (rRNAs), and transfer RNA (tRNAs). Phylogenetic trees reconstructed herein based on the BI and ML analyses consistently recovered monophylitic Athysanini, except Watanabella graminea (Athysanini) in Opsiini with high support values.

The corn leafhopper, Dalbulus maidis (DeLong and Wolcott) (Hemiptera: Cicadellidae), is an invasive insect that can cause damage to maize (Zea mays L.) in two ways: by direct feeding and the transmission of several plant pathogens. Dalbulus maidis is an invasive and serious economic pest of maize that has spread from its center of origin in Mexico to the southernmost parts of the United States. Prior to 2024, corn leafhoppers had not been documented in Oklahoma, and their spread northward toward the United States corn belt is of significant concern. Here, we provide the first reports of the insect in maize in several Oklahoma counties. Insect specimens were collected at various commercial and experimental field sites by Oklahoma State University research and extension personnel. The identity of the insect species was validated through morphological and molecular taxonomy. The presence records for the corn leafhopper presented here provide valuable information for future monitoring and management efforts of this economically important pest and disease.

Leafhoppers are economically important pests and may serve as vectors for pathogenic viruses that cause substantial crop damage. In this study, using deep transcriptome sequencing, we identified three novel viruses within the order Mononegavirales, including two viruses belonging to the family Rhabdoviridae and one to the family Lispiviridae. The complete genome sequences were obtained via the rapid amplification of cDNA ends and tentatively named Recilia dorsalis rhabdovirus 1 (RdRV1, 14,251 nucleotides, nt), Nephotettix virescens rhabdovirus 1 (NvRV1, 13,726 nt), and Nephotettix virescens lispivirus 1 (NvLV1, 14,055 nt). The results of a phylogenetic analysis and sequence identity comparison suggest that RdRV1 and NvRV1 represent novel species within the family Rhabdoviridae, while NvLV1 is a new virus belonging to the family Lispiviridae. As negative-sense single-strand RNA viruses, RdRV1 and NvRV1 contain the conserved transcription termination signal and intergenic trinucleotides in the non-transcribed region. Intergenomic sequence and transcriptome profile analyses suggested that all these genes were co-transcriptionally expressed in these viral genomes, facilitated by specific intergenic trinucleotides and putative transcription initiation sequences.

In recent years, phytoplasma diseases have increased and become serious in Egypt. Samples of carrot plants exhibiting resemble symptoms of phytoplasma diseases were collected from seven different cultivated areas in El Qalyubia governorate during the growing seasons 2021 and 2022; to detect phytoplasma infection used Light microscopy, Dienes' stain, transmission electron microscopy (TEM), and Nested-PCR. Dodder (Cuscuta campestris), leafhopper (Hebata decipiens), and seed transmission were used to study the transability of phytoplasma. The obtained results showed pleomorphic bodies in infected phloem tissues treated with Dienes' stain as irregular patches of intensely dark blue stained cells. However, a light microscope observed significant abnormal changes in infected tissues compared with healthy ones. Transmission electron microscopy (TEM) that observed phytoplasma units in the phloem tissue and deterioration in the ultrastructure of infected plants including malformed cells, thickness, and abnormal shape of the cell wall. But, due to inconsistent distribution within the plant, low titer, and fluctuation often hamper accurate phytoplasma detection. Therefore, a PCR was used to detect phytoplasma infection using the universal primer pairs P1/P7 and R16F2n/R16R2 that produce fragments at 1200 bp. For transmission of phytoplasma in carrot, dodder, and leafhoppers gave positive results and mechanical transmission gave negative results. Our results will provide a better understanding of the effects of phytoplasma infection in carrots, helping us to develop effective strategies for overcoming such diseases. [ABSTRACT FROM AUTHOR]

We evaluated the induction of plant volatile organic compounds (VOCs) in maize after the attack of two piercing-sucking maize hoppers: the specialist Dalbulus maidis and the oligophagous Peregrinus maidis. We analyzed VOCs in plants after feeding and oviposition by females of both species. We also contrasted VOCs induced by D. maidis males with those induced by females' infestation that comprised oviposition, to evaluate which VOC could be responsible for attracting an egg parasitoid. We quantified the damage performed by both hoppers and tested the behavioral response of the egg parasitoid Anagrus virlai to VOCs emitted by infested and healthy plants. Plants infested by D. maidis females released significantly more VOCs than the other treatments: healthy plants, plants infested by P. maidis females and plants infested by D. maidis males. β-Caryophyllene, α-bergamotene, β-farnesene and cis-3-hexenyl acetate dominated the volatile blend (46%) in plants infested by D. maidis females, while in those plants infested by P. maidis these compounds represented only 17%. Females of both hoppers inflicted a comparable amount of damage, in terms of feeding injuries and number of eggs laid. β-Caryophyllene and cis-3-hexenyl acetate were not induced in plants infested by D. maidis males, that had no oviposited eggs. Finally, females of the egg parasitoid oriented toward VOCs from plants infested by females of the specialist D. maidis, rather than those infested by the oligophagous P. maidis or those infested by D. maidis males. [ABSTRACT FROM AUTHOR]

Leafhoppers pose a significant threat to cotton production and leading to substantial losses when susceptible hybrids and improper insecticidal treatments are employed. Developing cotton cultivars with leafhopper resistance is crucial in mitigating this issue. In this study, we evaluated eighteen genotypes, including parental lines, F1 hybrids, and standard checks, during the Kharif 2022. The assessment was conducted in both field and polyhouse environments over a crop period from 30 to 120 days. Our findings revealed that parents, NDLH1938 and Suraksha, and three F1 hybrids TVH002 × Suraksha, NDLH1938 × Suraksha, and TVH002 × NDLH1938 exhibited significant resistance (p ≤ 0.05). They exhibited lower leafhopper populations, injury and susceptibility indexes, and host preference survival rates compared to the other genotypes. Stereo and field emission scanning electron microscopy (FESEM) unveiled the presence of glandular trichomes (GTs) and single-celled non-GTs with 2-8 branches on primary stem leaves. Trichomes rate increased upward on new leaves, establishing a negative correlation (trichome length r = -0.52, density r = -0.72) with leafhopper population. Additionally, morpho-biochemical traits such as reducing sugars, leaf thickness, chlorophyll, amino acids, and proteins were positively associated with pest density. Energy dispersive X-ray (EDS) spectroscopy indicated that high-field resistant hybrids had lower elemental composition. Furthermore, genotypes with higher gossypol and tannin levels experienced lower leafhopper infestations, suggesting that these compounds which may act as feeding deterrents. The study highlighted that a combination of various morpho-biochemical traits governs high-level resistance (R² = 0.98), rather than a single factor. These identified resistant genotypes can play a pivotal role in future breeding programs aimed at enhancing leafhopper resistance in cotton. [ABSTRACT FROM AUTHOR]

The US cherry and stone fruit industries have periodically experienced devastating outbreaks of X-disease phytoplasma (XDP) since the 1930s, with an ongoing epidemic occurring since 2010. This disease is critically impacting Prunus spp. and the stone fruit industry, causing underdeveloped, bitter, and misshapen fruit on economically important crops, primarily cherries, peaches, and nectarines, making the fruit unmarketable. Trees cannot recover from this disease and eventually die if they are not removed. It takes at least 1 yr for symptoms to appear, postinfection, which hinders disease management efforts. The phytoplasma, Candidatus Phytoplasma pruni, is a phloem-limited intracellular bacterium that is spread by grafting and leafhopper (Hemiptera: Cicadellidae) feeding. Several leafhopper species are known to transmit XDP, of which Colladonus spp. are considered the most important vectors in the Western United States and are native to this region. Colladonus spp. feed and oviposit on a wide variety of broadleaf perennial plants, including mallow, alfalfa, and clover. These plants are also hosts of the phytoplasma. In Western United States, these leafhoppers have 3 periods of adult activity: May–June, late July–August, and October. The highest rates of pathogen transmission likely occur during the last 2 activity periods due to the high abundance of leafhoppers and a postharvest increase of XDP titers in trees. Using known activity periods and host plants of the leafhoppers, growers can monitor and strategically manage the vectors, which, when combined with the removal of infected trees and ground-cover hosts, should help limit the spread of X-disease. [ABSTRACT FROM AUTHOR]

'Candidatus Phytoplasma ulmi' (Ca. P. ulmi) belongs to the ribosomal subgroup 16SrV-A and is associated with dieback, shoot proliferation and yellows disease on various Ulmus spp. Other plant species, such as Carpinus betulus and Prunus spp. have also been reported infected by the same pathogen. In 2021, in the frame of research activities focused on grapevine's Flavescence dorée (FD), one specimen of Orientus ishidae - an East Palearctic leafhopper that was identified as an alternative vector of FD phytoplasmas - was found harboring Ca. P. ulmi in southern Switzerland. No phytoplasmas were detected in plant samples taken in the same location. Orientus ishidae has already been reported to be able to acquire diverse phytoplasmas associated with other plant diseases, such as Peach X-disease. This is the first report of Ca. P. ulmi in Switzerland, as well as in O. ishidae. Ca. P. ulmi may potentially be present in the wild compartment of the Swiss Pre-alpine and Alpine range, but no dedicated survey has so far been conducted. In the case of O. ishidae, this finding highlights the broad affinity of such a species for the acquisition of several phytoplasmas. This calls for a further investigation regarding its potential role as a vector on various pathosystems of agronomic importance. [ABSTRACT FROM AUTHOR]

A field experiment was conducted at the Agricultural college, Naira during rabi, 2020-21 on the control of major insect pests on sesamum viz., leafhopper Hishimonus phycitis (Distant) and whitefly Bemisia tabaci (Gennadius) and phyllody disease. The results revealed that thiamethoxam 25WG @ 0.25 g/l was very effective against both the pests with 72.2 and 50.5% reduction in incidence, respectively. Thiamethoxam was also effective against phyllody (PDI of 5.72), and gave a maximum seed yield of 6.50 q/ha and B:C ratio (1:4.7). Seed treatment with imidacloprid 17.5SL @ 5 ml/kg seed stood as the next best with B:C ratio of 1:3.7. [ABSTRACT FROM AUTHOR]

Present study records two Opsius leafhopper species, Opsius richteri (Dlabola) and Opsius stactogallus Fieber from Delhi, India for first time. Earlier Opsius richteri had been described from Iran and Opsius stactogallus is distributed worldwide and now reported from India. This study reveals the new geographic distribution, and the species are redescribed and illustrated herein. [ABSTRACT FROM AUTHOR]

Sugar beet (Beta vulgaris L.) is the second sugar crop for sugar production after sugar cane worldwide. This plant is subjected to the infestation of several insect pests that cause considerable damage, especially leafhoppers, that can transmit phytopathogens (e.g., phytoplasma). In this work, we identified and described the leafhopper, Hebata (Alboneurasca) decipiens, in addition to the detection and molecular identification of Candidatus Phytoplasma that was transmitted by this leafhopper on sugar beet plants from naturally infected sugar beet plants to an uninfected one. The 16S rDNA gene from phytoplasma was amplified by a nested polymerase chain reaction (PCR) assay and directly sequenced using specific primer pairs DNA fragments. The resulting sequences were analyzed and compared with another phytoplasma sequence available at GenBank sequences performing BLAST using DNAMAN.

Abstract A novel geminivirus, soybean stay-green associated virus (SoSGV), was previously shown to cause soybean delayed senescence and is associated with the incidence of soybean stay-green syndrome. The modes of SoSGV transmission were not yet known. We captured insects belonging to 24 distinct species in a soybean field with the SoSGV outbreak and detected the presence of SoSGV only in leafhoppers and bean bugs (Riptortus pedestris). Caged feeding experiments using captured leafhoppers and bean bugs from soybean fields showed that leafhoppers, but not bean bugs, are vectors transmitting SoSGV. The common brown leafhopper (Orosius orientalis) is identified as the dominant leafhopper species and can establish colonies feeding on soybean plants in experimental conditions. An investigation of SoSGV defective DNA revealed that soybean genomic DNA fragments could be inserted into the SoSGV genome, while sequences from wild soybean, red bean, and cowpea were also identified. We further showed that the common brown leafhopper could transmit SoSGV to wild soybean and red bean plants, emphasizing a vector’s role of the leafhopper in the transmission of SoSGV in the field.

Abstract In recent years, the emergence of soybean stay-green syndrome (SGS), also referred to as ‘zhengqing’, in the Huang-Huai-Hai region of China has resulted in significant yield losses. SGS is a phenomenon characterized by the delayed senescence of soybean, resulting in stay-green leaves, flat pods, and stunted seed development at harvest. We previously identified a distinct geminivirus, named soybean stay-green associated geminivirus (SoSGV), as the causative agent of SGS by fulfilling Koch’s postulates. To further understand the epidemiology of SoSGV, in this study, we collected 368 stay-green samples from 17 regions in 8 provinces including the Huang-Huai-Hai region and surrounding areas. The results showed that 228 samples tested positive for SoSGV (61.96%), and 96.93% of these positive samples showed severe pod deflation. Our epidemiological assessment reveals that SGS caused by the SoSGV is prevalent in the fields, and it is undergoing geographical expansion and genetic differentiation. Additionally, we determined other natural hosts grown in the Huang-Huai-Hai region. By capturing insects in the field and conducting laboratory vector transmission tests, we confirmed that the common brown leafhopper (Orosius orientalis) is the transmission vector of SoSGV. With a better understanding of the transmission and epidemiology of SoSGV, we can develop more effective strategies for managing and mitigating its impact on soybean yields.

The bacterial genus Wolbachia induces reproductive abnormalities in its insect host, including cytoplasmic incompatibility (CI), which causes embryonic death in the crossing of infected males and uninfected females. Hence, Wolbachia-based strategies are employed to control insect pests. However, Wolbachia does not naturally infect Matsumuratettix hiroglyphicus (Matsumura), the main vector of the phytoplasma causing the sugarcane white leaf (SCWL) disease. In this study, the wYfla Wolbachia strain, which induces strong CI in its original host, was microinjected into nymphs of M. hiroglyphicus. Molecular detection revealed that Wolbachia was successfully transinfected into the recipient host, with an infection frequency of 55–80% in up to eight generations after transinfection. Wolbachia exhibited no significant detrimental effects on the developmental time of the immature stages, adult emergences, and female longevity, whereas the lifespan of transinfected males was decreased. Reciprocal crossing revealed that Wolbachia infection did not affect the number of eggs laid per female. However, the hatching rate produced by the pairs between the transinfected males and naturally uninfected females significantly decreased. The evidence of Wolbachia transmitted through the generations tested and partial CI occurrence in transinfected M. hiroglyphicus highlights the possibility of the future development of Wolbachia-based strategies for controlling the vector of SCWL.

This document presents the findings of a study on the impact of weather parameters and sowing dates on insect pests in mungbean crops. The study found that the population of pests such as whitefly, leafhopper, thrips, and pod borer was influenced by weather conditions. Specifically, higher temperatures and humidity were associated with increased pest populations. The study also found that the date of sowing affected pest populations and the extent of pod borer damage. The findings align with previous research on the topic. [Extracted from the article]

Cotton (Gossypium spp) remains a significant source of income in Africa. However, production is limited by high input costs that reduce profit margins. This study aimed to conduct cost analysis on field trials that were conducted to evaluate the effect of chemical insecticides, Chlorpyrifos® 480 EC, Karate® EC, and Bandit® 350 SC compared with biopesticides, Eco-Bb®, Bolldex®, Delfin®, NOMU-PROTEC® and Bb endophyte on the control of cotton insect pests. Delfin® (US$602) was the most expensive pesticide, followed by Bolldex® (US$495.74), while the cheapest pesticide was Chlorpyrifos® (US$28). Other input costs were US$1 396.50 per hectare, with the highest labor cost of US$544. The minimal cost of production from the bollworm trial was recorded from the application of Karate® (US$1 455), while Delfin® (US$1 999) was the highest. Maximum average seed cotton yield was recorded with Bolldex® (6 402 kg ha-1); however, the maximum net profit of up to US$1 445.26 per hectare was registered with Karate® with the highest cost-benefit ratio of 1.8. The average highest seed cotton yield was obtained with Bandit® (6 394 kg ha-1) followed by Bb endophyte (6 297 kg ha-1) in the leafhopper trial. Bandit® and Karate® had the highest net profits of US$ 1,712 and US$ 1,253, respectively. The Bandit® treatment had the highest costbenefit ratio of 2. Generally, biopesticide application was found to be more expensive than chemical insecticides; however, they were all profitable. [ABSTRACT FROM AUTHOR]

The corn leafhopper Dalbulus maidis (Hemiptera: Cicadellidae) is a serious maize pest widely distributed on the American continent. This is the most common leafhopper feeding on corn crops in Argentina and Brazil, causing major economic losses due to its capability to transmit important pathogens, such as corn stunt spiroplasma, and considerably decreasing crop yield. One way to increase crop yield is to elevate fertilizing doses of nitrogen and phosphorus, although this could translate into an increase in pest populations, since changes in host plant quality makes them more attractive to herbivorous insects, positively influencing their population dynamics. This study aims to assess the oviposition preference and the olfactory response of D. maidis to corn plants subject to three levels of nitrogen fertilization (100 ppm, 200 ppm and 300 ppm). Olfactory response was evaluated in a static-air four-way olfactometer using maize plants with different nitrogen fertilization levels as odor sources. Additionally, plants with different nitrogen fertilization levels were offered to females in a multiple-choice assay to assess their oviposition preference. The olfactory response of D. maidis was influenced by nitrogen fertilization, as females oriented toward plants treated with high fertilization levels. Similarly, oviposition preference assays showed that D. maidis females preferred to lay its egg in plants with high fertilization levels. The results herein reported could contribute to the design of integrated pest management strategies that promote balance between crop fertilization to improve yield and insect vector management. [ABSTRACT FROM AUTHOR]