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Helicoverpa armigera (Hübner) is one of the most prominent polyphagous species of the Heliothinae pest complex that inflicts severe damage to a wide range of crops in India. Knowledge regarding the population structure of the pest species, whether morphological or genetic, is considered as an essential tool in making effective management decisions. Thus here, we performed the phenotypic characterization of H. armigera populations collected from varied geographic locations across India. Studied populations differed significantly for several external morphometric traits studied at larval, pupal and adult stages. Significant differences were also observed with respect to the intensity of black pigmentation on larval body as well as adult eye and forewing colour patterns. Besides external phenotypic traits, the length of genital organs like aedeagus and valva in males, and bursa copulatrix and bursa seminalis in females also differed significantly amongst populations. The dendrogram based on selected traits showed clear cut differentiation of studied populations into two major groups, one including all the South Zone populations and the other having populations from North and Central Zones. Differences based on phenotyping in the present study indicate the possibility of the existence of different subspecies within the Indian populations of H. armigera. [ABSTRACT FROM AUTHOR]

This study reports a new Helicoverpa armigera nucleopolyhedrovirus (NPV) isolated from Heliothis peltigera (Denis & Schiffermuller), collected in the vicinity of Adana, Turkey. Infection was confirmed by tissue polymerase chain reaction and sequence analysis. Results showed that dead H. peltigera larvae contain Helicoverpa armigera nucleopolyhedrovirus. Thus, the isolate was named as HearNPV-TR. Microscopy studies indicated that occlusion bodies were 0.73 to 1.66 μm in diameter. The nucleocapsids are approximately 184 × 41 nm in size. The genome of HearNPV-TR was digested with KpnI and XhoI enzymes and calculated as 130.5 kb. Phylogenetic analysis showed that HearNPV-TR has close relation with the H. armigera SNPV-1073 China isolate. The Kimura analysis confirmed that the isolate is a variant of H. armigera NPV. Bioassays were performed using six different concentrations (1 × 10³ to 1 × 108 occlusion bodies (OBs)/mL) on 2nd instar larvae of H. peltigera, H. armigera, Heliothis viriplaca, Heliothis nubigera. LC50 values were calculated to be 9.5 × 10³, 1.9 × 104, 8.6 × 104 and 9.2 × 104 OBs/mL within 14 days, respectively. Results showed that it is a promising biocontrol agent against Heliothinae species. [ABSTRACT FROM AUTHOR]

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Helicoverpa gelotopoeon, the SouthAmerican bollworm, is a polyphagous pest of the Heliothinae complex that causes damage to soybean, cotton, and chickpea crops. Some species within this complex have developed resistance to genetically modified crops and insecticides, which has led to increased interest in their genetic diversity and population structure. The objective of this study was to characterize biological and reproductive parameters of two populations of H. gelotopoeon collected in two different provinces of Argentina. Intra- and inter-population crosses revealed that H. gelotopoeon populations from both regions of Argentina did not present evidence of pre-zygotic and post-zygotic incompatibility, suggesting that Tucumán and Córdoba populations of H. gelotopoeon belong to a single wide-ranging species. Our data support the occurrence of substantial gene flow between H. gelotopoeon populations, probably due to the widely documented, long-range migratory capacity of Heliothinae species. [ABSTRACT FROM AUTHOR]

DNA barcoding and morphological characters together with thorough bioecological investigations to diagnose field bean pod borer, Adisura atkinsoni Moore, 1881 an important pest was carried out. A. atkinsoni has a limited host range. The incidence of Adisura was higher on local varieties (photo sensitive) compared to HA4 hybrid (photo-insensitive). The field bean pod borer appeared during middle of October and continue to March. The undefined taxa were identified using both female and male genitalia. But since they could be differentiated from their morphologically closest relative, they were marked as sensu lato. While doing BLAST analysis, the mitochondrial COI Sequence of Adisura specimens collected from Bengaluru showed similarity to A. bella. In the phylogenetic tree, these two samples Sp1 and Sp2 separate new sub-clade which stands separately from the rest of the Adisura species. It was identified that the lepidopteran samples collected from Bengaluru are Adisura and the DNA sequences did not match with any of the existing species of Adisura. The shift in this pest's prevalence has been discussed. [ABSTRACT FROM AUTHOR]

The tobacco budworm, Heliothis virescens (F.) (Lepidoptera: Noctuidae), damages soybean crops by feeding on the leaves, pods, and terminal buds. The purpose of this study was to evaluate antibiosis resistance to H. virescens by different soybean cultivars. Soybean cultivars evaluated were P 98Y30 RR, NA 7337 RR, SYN 1163 RR, NK 7059 RR, ANTA 82 RR, M 7110 IPRO, BRS 8160 RR, BRSGO Jataí, and IAC 100. The variables analyzed were duration of the larval stage, percentage of larval survival, larval weight at 10 d, duration of the prepupal stage, percentage of prepupae survival, duration of the pupal stage, percentage of pupal survival, pupal weight at 24 h, total duration of the life cycle, overall survival, and adult longevity. The cultivars BRS 8160 RR, BRSGO Jataí, and P 98Y30 RR were highly susceptible to tobacco budworm, whereas IAC 100 and M 7110 IPRO showed antibiosis resistance to H. virescens. [ABSTRACT FROM AUTHOR]

Helicoverpa gelotopoeon (Dyar) (Lepidoptera: Noctuidae) is a polyphagous pest that belongs to the Heliothinae complex, and has been described as feeding on numerous crops. Larvae damage mainly pods and seeds of soybean and other legumes. Adaptation to different host plants might reduce gene flow between phytophagous insect populations, which could lead to reproductive isolation. Therefore, studies on gene flow among host-associated populations are necessary to design management strategies. The objective of this study was to evaluate reproductive compatibility between 2 populations of H. gelotopoeon coming from different host plants. We collected H. gelotopoeon larvae in alfalfa and soybean crops, and studied biological and reproductive parameters, and mating compatibility. Helicoverpa gelotopoeon populations from soybean and alfalfa reared on artificial diet showed similar biological and reproductive characteristics. Intra- and inter-population crosses revealed that there are no signs of host-associated isolation, allowing gene exchange between these populations, which can be explained by the high mobility and generalist behavior of this species. This information will be useful to establish control measures for this pest. [ABSTRACT FROM AUTHOR]

Heliothine larvae, especially early instars, are difficult to identify, and determinations sometimes rely on indirect information such as origin and host data. The introduction of Helicoverpa armigera (Hübner) into the New World has undermined the reliability of host and origin data to identify intercepted Helicoverpa larvae, and suspect Heliothinae/ Helicoverpa larvae intercepted at U.S. ports of entry are now screened for H. armigera and Helicoverpa zea (Boddie) using molecular methods. Here, we analyze heliothine larvae intercepted during 2014–2106 to identify nontargets and evaluate morphological characters traditionally used to separate taxa. In total, nine species were identified, with Chloridea virescens (Fabricius) making up the bulk of interception records. The majority of heliothine suspects originate from Mexico and Peru on pigeon pea, chickpea, tomatillo, pea, and corn. Helicoverpa armigera is commonly intercepted from Peru on pea. Chloridea virescens is recorded from every country where interceptions were identified for this study except Guatemala and is found on multiple hosts. Identification issues and specific host/origin associations are discussed in detail. [ABSTRACT FROM AUTHOR]

Copyright of SHILAP Revista de Lepidopterologia is the property of Sociedad Hispano-Luso-Americana de Lepidopterologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Heliothine species (Lepidoptera: Noctuidae, Heliothinae) include some of the world's most devastating pest species, such as Heliothis virescens (Fabricius) in the Americas and Helicoverpa armigera (Hübner) in the Old World. Sex pheromone communication of these agricultural pest species has been investigated from pheromone receptors (PRs) to brains and behavior in detail. In recent years, great progress has been made in the mechanistic dissection of pheromone reception, demonstrating that PRs play a key role in determining the response characteristics of pheromone‐sensitive olfactory receptor neurons. In this review, we focus on the functional characterization of PRs in heliothine species, and summarize recent progress in the identification of receptors tuned to principal sex pheromone components including Z11‐16:Ald, Z9‐16:Ald, Z9‐14:Ald, and other related alcohols and acetates. Evolution of PRs in ligand selectivity is also discussed. The efficiency and faithfulness of three frequently used heterologous expression systems – Xenopus laevis Daudin oocytes, modified HEK 293 cells, and Drosophila 'empty neuron' mutants – are compared, and the research strategies, skills, and perspectives in the studies are envisioned. Finally, we propose future research topics on PRs in heliothine species. [ABSTRACT FROM AUTHOR]

Background: Combined use can be an effective measure to improve pest control by viruses and parasitic wasps. However, not all combinations of natural enemies show improved effects. Helicoverpa armigera nucleopolyhedrovirus (HearNPV) and Campoletis chlorideae Uchida are two important natural enemies of Helicoverpa armigera. This study aimed to investigate the combined effects of C. chlorideae and HearNPV against H. armigera larvae and the impact of HearNPV on C. chlorideae., Results: The combination of HearNPV and C. chlorideae exerted increased mortality on H. armigera when C. chlorideae parasitized larvae one day after infection with HearNPV. C. chlorideae could distinguish between HearNPV-infected and noninfected larvae. Besides influencing host selection of C. chlorideae, HearNPV infection had negative effects on the development and reproduction of C. chlorideae. The developmental time of C. chlorideae was significantly prolonged and the percentage of emergence and adult eclosion of C. chlorideae was lower in infected hosts. The adult wasps were also smaller in body size, and female adults had fewer eggs when they developed in virus-infected hosts., Conclusions: HearNPV combined with C. chlorideae could improve the efficacy of biological control against H. armigera. The results provided valuable information on the importance of timing in the combined use of HearNPV and C. chlorideae for the biological control of H. armigera. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

Copyright of Chinese Journal of Applied Entomology is the property of Chinese Journal of Applied Entomology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The chemical composition of cuticular hydrocarbons differs qualitatively and quantitatively among insect species. These differences convey species-specific information about host suitability to foraging parasitoids, enabling them to discriminate between the host and non-host species. Specialist parasitoids that parasitize fewer host species are predicted to use host-specific cues compared to generalists that have evolved to use common cues present in multiple potential host species. Here, we tested the above hypothesis by evaluating two parasitoids with varying levels of host specificity, Microplitis croceipes (specialist) and Cotesia marginiventris (generalist), for their responses to cuticular extracts of three caterpillar species, Chloridea virescens, Helicoverpa zea, and Spodoptera exigua. First, we compared the cuticular profiles of the three caterpillar species and found that C. virescens and H. zea were qualitatively similar in cuticular composition, whereas S. exigua differed qualitatively and quantitatively from the other two. In contact bioassays, both parasitoid species were behaviorally arrested by the host cuticular extracts, with specialist M. croceipes able to discriminate between the cuticular extracts of its host and non-host caterpillar species. Assessment with the coupled gas chromatography-electroantennogram detection (GC-EAD) revealed qualitative and quantitative differences in parasitoids' antennal responses to the components of cuticular extracts of host species, with M. croceipes showing greater antennal response than generalist C. marginiventris. The data implicated 13-methylhentriacontane as a probable host-specific kairomone used by specialist M. croceipes. These results suggest that specialist parasitoids like M. croceipes may exploit the differences in the composition of cuticular chemicals of caterpillars as cues for host recognition and discrimination. [ABSTRACT FROM AUTHOR]

Chemical control methods to prevent crop damage have long been directly implicated in the selection of lepidoptera insect populations resistant to insecticides. More recently, new products featuring different modes of action (MoA), developed to mitigate the negative effects of control management on both producers and the environment, are rapidly losing efficacy due to the emergence of resistant insects. Among these, certain resistances are associated with molecular changes in the genomes of pest insects that are valuable for developing molecular markers for diagnostic tools, particularly the point mutations. Molecular diagnosis represents an innovative solution for insecticide resistance management (IRM) practices, allowing for the effective monitoring of insecticide resistance. This approach facilitates decision making by enabling the timely alternation between different modes of action (MoAs). In this context, this review focuses on the major lepidopteran pests that affect globally significant crops, discussing the impacts of insecticide resistance. It gathers literature on diagnostic methods; provides a comparative overview of the advantages of different techniques in terms of efficiency, cost, precision, sensitivity, and applicability; and highlights several novel diagnostic tools. Additionally, this review explores the coffee leaf miner, Leucoptera coffeella, as an applied model to illustrate potential approaches for more effective and sustainable control strategies. [ABSTRACT FROM AUTHOR]

The cotton bollworm, Helicoverpa armigera (Hübner), is one of the important insect pests of cotton throughout the world. Considering the adverse effects of chemical pesticides, it is necessary to find eco-friendly substitute agents for managing insect pests, including H. armigera. Plant-derived insecticides have been introduced as suitable candidates to replace detrimental synthetic chemicals. In this study, the toxicities of water, ethanol, and n-hexane extracts of eucalyptus and thyme, as well as their wettable powder formulations, against H. armigera larvae were investigated. The treated larvae represented different degrees of abnormalities, such as larva-pupa intermediate and pupa-adult stages in their different ages until they turned into pupae and completed the breeding cycle. The results showed that the considered formulations of extract of n-hexane and ethanol, and concentrations had significant effects on the mortality rates of the larvae (P≤0.05) but the interaction of extracts and concentrations was not significant. The mortality rates were enhanced by increasing the tested concentrations. The LC50 values (lethal concentrations to kill 50% of the tested insects) were 343.758% (water), 10.171% and 23.264% (ethanol), and 0.404% and 0.490% (n-hexane) for the eucalyptus and thyme extracts within 24 hours, respectively, indicating higher toxicities of n-hexane extracts. The LC50 values of wettable powder formulations of the thyme and eucalyptus extracts were 120.68% and 177.75% (water) and 36.17% and 74.65% (ethanol), respectively, which represented the greater toxicities of these types of formulations. Therefore, the wettable powder formulations of ethanol and water extracts of thyme were more toxic than their solution formulations. Based on the results of this study, wettable powder formulation of eucalyptus and thyme extracts had promising potential for H. armigera management. [ABSTRACT FROM AUTHOR]

Simple Summary: The fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae), has caused significant crop damage worldwide, particularly to maize and other economically important crops. While chemical control remains common, understanding pest behavior and host plant preferences could enable more sustainable management approaches. This study investigated the oviposition preferences of S. frugiperda among various host plants using no-choice, two-choice, and multiple-choice bioassays. In no-choice bioassays, para grass, maize, and napier grass were highly attractive for S. frugiperda oviposition, while plants like sweet sorghum, sunhemp, desmodium, Egyptian clover, molasses grass and mung bean were less preferred. Two-choice bioassays revealed differing levels of attractiveness and repellency among plant combinations. In multiple-choice experiments simulating intercropping scenarios, the number of S. frugiperda eggs and egg masses varied across maize, sunhemp, desmodium, and the cage walls. These findings suggest that strategic intercropping of attractive and less preferred host plants could be a promising approach to disrupt S. frugiperda oviposition and reduce subsequent larval infestations. This study provides valuable insights into the ovipositional behavior of S. frugiperda and highlights the potential of intercropping as an environmentally friendly pest management strategy. By reducing reliance on chemical pesticides, such approaches can contribute to sustainable agriculture and protect crop yields. The fall armyworm (FAW), Spodoptera frugiperda, is a major polyphagous pest that mainly feeds on maize and other cash crops. Understanding S. frugiperda's behavior on different host plants facilitates the development of effective integrated pest management (IPM) plans. Therefore, this study investigated the oviposition preferences of S. frugiperda females among different host plants using no-choice, two-choice, and multiple-choice bioassays. In no-choice bioassays, para grass, Urochloa mutica (Forssk.) (Poales: Poaceae); maize, Zea mays (L.) (Poales: Poaceae); and napier grass, Pennisetum purpureum (Schumach) (Poales: Poaceae) were identified as highly attractive, while sweet sorghum, Sorghum dochna (Forssk.) (Poales: Poaceae); sunhemp, Crotalaria juncea (L.) (Fabales:Fabacea); Egyptian clover, Trifolium alexandrinum (L.) (Fabales:Fabacea); desmodium, Desmodium uncinatum (Jacq.) (Fabales:Fabacea); natal grass, melinis repens (Zizka) (Poales: Poaceae); molasses grass, Melinis minutiflora (P.Beauv.) (Poales: Poaceae); and mung bean, Vigna radiata (R. wilczek) (Fabales: Fabaceae) exhibited reduced oviposition effects. Two-choice bioassays revealed different levels of attractiveness and repellency among different plant combinations. In multiple-choice bioassays, mimicking an intercropping scenario, differences in the number of eggs and egg mass were observed for M:S:D:W (maize, sunhemp, desmodium, and cage wall), S:D:M:W (sunhemp, desmodium, maize, and cage wall), and D:M:S:W (desmodium, maize, sunhemp, and cage wall). This study provides insights into the egg-laying preferences of S. frugiperda females among different host plants, valuable for the management of S. frugiperda. This encourages further research and further identification of novel repellent and attractant host plants, which will ultimately contribute to the development of sustainable and environmentally friendly crop production practices and techniques. [ABSTRACT FROM AUTHOR]

Copyright of Plants, People, Planet is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The sublethal toxic effects of pyriproxyfen, an insect juvenile hormone analog (JHA) insecticide, on the circulating metabolite balance in the Neotropical brown stink bug, Euschistus heros, one of the main agronomic pests in South America, were investigated. Our objectives were to evaluate changes in the baseline levels of lipids and carbohydrates, along with three selected micro-elements—nickel (Ni), copper (Cu), and zinc (Zn)—in the hemolymph of adult E. heros, following the application of a predetermined LC30 of pyriproxyfen (single topical application) in fourth-instar nymphs (N4). Hemolymph was sampled using glass capillaries, with the resulting concentrations of lipids and carbohydrates determined through vanillin- and anthrone-positive reactions, respectively, and micro-element analysis was performed through total reflection X-ray fluorescence (TXRF) spectrometry. Lipids are the main and more stable energy metabolites for E. heros, with a proportion of 2:1 compared to carbohydrate levels. A remarkable sensitivity of carbohydrate levels to sublethal pyriproxyfen exposure, irrespective of sex, was observed. Baseline micro-element levels based on untreated control insects indicate sex-based differences in Ni and Zn, but not in Cu, concentrations. After insecticide exposure, the levels of these micro-elements were variable, with Ni and Zn generally decreasing and Cu decreasing in females but nearly doubling in males. The observed disproportion in lipids, carbohydrates, and inorganic micro-elements suggests potential physiological shifts triggered by pyriproxyfen activity in E. heros during late juvenile stages. [ABSTRACT FROM AUTHOR]

The majority of field corn, Zea mays L. in the southeastern United States has been genetically engineered to express insecticidal toxins produced by the soil bacterium, Bacillus thuringiensis (Bt). Field corn is the most important mid-season host for corn earworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), which has developed resistance to all Cry toxins in Bt corn. From 2020 to 2023, corn earworm pupae were collected from early- and late-planted pyramided hybrids expressing Bt toxins and non-Bt near-isolines in North and South Carolina (16 trials). A total of 5,856 pupae were collected across all trials, with 55 and 88% more pupae collected in later-planted trials relative to early plantings in North and South Carolina, respectively. Only 20 pupae were collected from hybrids expressing Cry1F + Cry1Ab + Vip3A20 across all trials. Averaged across trials, Cry1A.105 + Cry2Ab2 hybrids reduced pupal weight by 6 and 9% in North and South Carolina, respectively, relative to the non-Bt near-isoline. Cry1F + Cry1Ab hybrids reduced pupal weight on average by 3 and 8% in North and South Carolina, respectively, relative to the non-Bt near-isoline. The impact of the Bt toxins on pupal weight varied among trials. When combined with data from 2014 to 2019 from previous studies, a significant decline in the percent reduction in pupal weight over time was found in both states and hybrid families. This study demonstrates a continued decline in the sublethal impacts of Bt toxins on corn earworm, emphasizing the importance of insect resistance management practices. [ABSTRACT FROM AUTHOR]

The armyworm, Spodoptera litura Fabricius, 1775 (Noctuidae: Lepidoptera) is a serious and emerging insect pest of sugar beet in India, resulting in significant yield losses. A phylogenetic tree was constructed using the CLUSTAL W and neighbour joining technique, and a neighbour joining haplotype network was formed using PopArt to assess the relationships between S. litura haplotypes. The evolutionary divergence of different strains of Indian-origin S. litura was calculated using the p-distance method in MEGA 11. Neutrality indices, including Tajima's D, Fu, and Li's F, was calculated to test the hypothesis of selective neutrality using DnaSPv6. Larval identification relied on the morphological characteristics, while the molecular characterization utilized the mitochondrial cytochrome oxidase I gene with universal primers (LCO1490 and HCO2198). A DNA fragment of approximately 700 bp from mitochondrial COI revealed two different strains (OP420870 and OP117231) infesting sugar beet crops under Indian subtropical conditions. The amplified barcode sequences exhibited variations in both strains, with genetic divergence ranging from 0.0 to 0.79. The strains OP420870 and OP117231 displayed maximum divergence at 0.74 and 0.73, respectively. Interpopulation nucleotide differences (Kxy) and the average number of nucleotide substitutions per site between populations (Dxy) in different states of India were calculated at 336.42 and 0.61, respectively. The pairwise Fst value was 0.63, with an Nm value of 0.15. One of the identified strains of S. litura in this study was also found to be a haplotype. This study provides valuable insights into the genetic characterization of S. litura infesting sugar beet crops in Indian subtropical conditions, contributing to the understanding of its population structure and diversity. The findings enhance our knowledge of S. litura infestations and can aid in the development of effective strategies for pest management and crop protection in sugar beet. [ABSTRACT FROM AUTHOR]

Iran is a country characterized by high biodiversity and complex biogeographic patterns. Its diverse landscape and steep climatic gradients have resulted in significant faunal diversity and high level of endemism. To better understand these patterns, we investigated the historical environmental drivers that have shaped Iran's current geological and climatological conditions, and, consequently, have shaped the current zoological distribution patterns. Furthermore, we provide an overview of the country's zoological diversity and zoogeography by reviewing published studies on its fauna. We analyzed nearly all available catalogs, updated checklists, and relevant publications, and synthesized them to present a comprehensive overview of Iran's biodiversity. Our review reports approximately 37,500 animal species for Iran. We also demonstrated that the country serves as a biogeographic transition zone among three zoogeographical realms: the Palearctic, Oriental, and Saharo-Arabian, where distinct faunal elements intersect. This biogeographic complexity has made it challenging to delineate clear zoogeographical zones, leading to varying classifications depending on the taxon. The uplift of mountain ranges, in particular, has played a crucial role in shaping faunal diversity by serving as barriers, corridors, and glacial refugia. These mountains are largely the result of orogeny and plate collisions during the Mesozoic and Cenozoic eras, coupled with the development of the Tethyan Sea and the uplift of several ranges during the Miocene. Despite these insights, our understanding of biodiversity distribution in Iran remains incomplete, even for some well-studied taxa, such as certain vertebrate families and arthropods. We highlight the existing gaps in knowledge regarding zoogeographical patterns and propose approaches to address these gaps, particularly concerning less-studied species and the highly diverse group of insects. [ABSTRACT FROM AUTHOR]

In northwest China, changes in cultivation patterns and the scarcity of preferred hosts have forced Helicoverpa armigera to feed on the marginal host walnut (Juglans regia). However, the mechanisms allowing this adaptation remain poorly understood. Here, we investigated the behavioral, physiological, and molecular mechanisms underlying the local adaptation of this pest to walnut fruits. The green husk and shell generally contained higher levels of phytochemicals than the kernel. Bioassays revealed that the phytochemical-rich green husk and shell were less preferred, reduced larval fitness and growth, and elevated the activity of detoxification enzymes compared to the nutrient-rich kernel, which were further supported by a larger number of upregulated detoxification genes in insects fed green husks or shells based on transcriptome sequencing. Together, these data suggest that P450 genes (LOC110371778) may be crucial to H. armigera adaptation to the phytochemicals of walnuts. Our findings provide significant insight into the adaptation of H. armigera to walnut, an alternative host of lower quality. Meanwhile, our study provides a theoretical basis for managing resistance to H. armigera larvae in walnut trees and is instrumental in developing comprehensive integrated pest management strategies for this pest in walnut orchards and other agricultural systems. [ABSTRACT FROM AUTHOR]

Macdunnoughia hybrida is a polyphagous herbivorous moth within the family Noctuidae. In this study, we sequenced and analyzed the complete mitochondrial genome (mitogenome) of M. hybrida. This mitogenome was 15,382 bp long and encoded 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), and two ribosomal RNA unit genes (rRNAs). Except for cox1 started with CGA, all other PCGs started with the standard ATN codons. Most of the PCGs terminated with the stop codon TAA, whereas cox1, cox2 and nad4 end with the incomplete codon T−−. The whole mitogenome exhibited heavy AT nucleotide bias (80.7%). Gene order was conserved and identical to most other previously sequenced Noctuidae. Phylogenetic analysis positioned M. hybrida in a well-supported clade with Diachrysia nadeja and three Ctenoplusia species. The relationships (Catocalinae + (Plusiinae + (Acronictinae + (Heliothinae + (Amphipyrinae + (Hadeninae + Noctuinae)))))) were supported within Noctuidae. [ABSTRACT FROM AUTHOR]

Because of the recent presence of Helicoverpa armigera in Brazil and Paraguay in 2013, pheromone traps were deployed in chickpea crops at 2 localities in Tucumán province to determine if this noctuid was present in Argentina. This pest was detected at both locations, confirming the presence of H. armigera in Argentina for first time. [ABSTRACT FROM AUTHOR]

The Old World bollworm, Helicoverpa armigera (Hübner), and the corn earworm, H. zea (Boddie), are two of the most important agricultural pests in the world. Diagnosing these two species is difficult—adults can only be separated with a complex dissection, and larvae cannot be identified to species using morphology, necessitating the use of geographic origin for identification in most instances. With the discovery of H. armigera in the New World, identification of immature Helicoverpa based on origin is no longer possible because H. zea also occurs in all of the geographic regions where H. armigera has been discovered. DNA barcoding and restriction fragment length polymorphism (RFLP) analyses have been reported in publications to distinguish these species, but these methods both require post-PCR processing (i.e., DNA sequencing or restriction digestion) to complete. We report the first real-time PCR assay to distinguish these pests based on two hydrolysis probes that bind to a segment of the internal transcribed spacer region 2 (ITS2) amplified using a single primer pair. One probe targets H. armigera, the second probe targets H. zea, and a third probe that targets a conserved segment of 18S rDNA is used as a control of DNA quality. The assay can be completed in 50 minutes when using isolated DNA and is successfully tested on larvae intercepted at ports of entry and adults captured during domestic surveys. We demonstrate that the assay can be run in triplex with no negative effects on sensitivity, can be run using alternative real-time PCR reagents and instruments, and does not cross react with other New World Heliothinae. [ABSTRACT FROM AUTHOR]

Copyright of SHILAP Revista de Lepidopterologia is the property of Sociedad Hispano-Luso-Americana de Lepidopterologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Helicoverpa armigera (Hübner) is a highly polyphagous insect pest of worldwide occurrence, including India. In the present study, a detailed morphological assessment of H. armigera showed the following: typically dome-shaped egg with ribbed surface; larva having coriaceous skin, biordinal crochets and 11 primary setae on the prothoracic segment; pupa adecticous and obtect with prominent posterior tip cremaster; and adult forewings characterized by the presence of 7-8 black spots along the apical margin and a reniform shaped brown marking, more prominent on the underside. Adults exhibit sexual dimorphism in the colour of vestiture and forewings. The genitalic traits like the presence of usually 12 or less sets of cornuti in aedeagus, apically broadened harpe having length ranging between 4.5 to 4.9 mm and a single lobe at the base of everted vesica in males, and four distinct signa on bursa copulatrix in females, also distinguishes it from other congeneric species. [ABSTRACT FROM AUTHOR]

The taxonomy of the Heliothinae subfamily is complex, often becoming an obstacle in the identification of these species, especially during the larval stage. An alternative is the use of molecular methods such as the PCR-RFLP technique (or Restriction Fragment Length Polymorphism), which helps to aid and complement the identification of some heliothine species. The aim of this study was to establish the PCR-RFLP profile using molecular markers for the identification of four heliothine species. Specific primers were constructed for the amplification of the cytochrome oxidase I (COI) and elongation factor 1 alpha (EF-1) genes for identifying Helicoverpa armigera, H. zea, H. gelotopoeon, and Chloridea virescens species. In the digestion of the COI gene with the BfaI enzyme, fragments of 294 bp and 321 bp were obtained for H. armigera, while there was no digestion for H. zea, H. gelotopoeon, and C. virescens. The HpaI enzyme produced fragments of 58 bp and 557 bp for H. gelotopoeon, while there was no digestion for H. armigera, H. zea, and C. virescens. The digestion of the EF-1 gene with the EcoRV enzyme produced fragments of 142 bp and 964 bp for C. virescens, while there was no cleavage for the other heliothines. These molecular markers can help the entomologists, aiding in the discrimination between H. zea, H. armigera, H. gelotopoeon, and C. virescens, and can also be used as a tool for monitoring the spread of these pests in agricultural regions.

Simple Summary: Old World bollworm is a moth species that causes significant damage to a wide range of agricultural crops. This species was once confined to the eastern hemisphere but has recently spread throughout South America and the Caribbean and has the potential to establish in North America. Molecular detection methods for Old World bollworm have been developed to track its spread and rapidly differentiate it from the native sibling species, corn earworm. Currently, droplet digital PCR (ddPCR) is a preferred method for bulk screening as it is highly accurate and tolerant of PCR inhibitors; however, real-time PCR is less expensive and more widely available in molecular labs. Improvements to DNA extraction yield and purity are crucial for real-time PCR assay optimization, but these improvements must be time- and cost-efficient. In this study, we improve upon previously published bulk DNA extraction methods by reducing bench time and costly materials. Our results indicate that the addition of caffeine and RNase A improves DNA extraction, resulting in higher amounts of target DNA in real-time PCR. Such improvements will enable the use of high throughput screening methods across multiple platforms to improve the probability of detection of Old World bollworm. Helicoverpa armigera is among the most problematic agricultural pests worldwide due to its polyphagy and ability to evolve pesticide resistance. Molecular detection methods for H. armigera have been developed to track its spread, as such methods allow for rapid and accurate differentiation from the native sibling species H. zea. Droplet digital PCR (ddPCR) is a preferred method for bulk screening due to its accuracy and tolerance to PCR inhibitors; however, real-time PCR is less expensive and more widely available in molecular labs. Improvements to DNA extraction yield, purity, and throughput are crucial for real-time PCR assay optimization. Bulk DNA extractions have recently been improved to where real-time PCR sensitivity can equal that of ddPCR, but these new methods require significant time and specialized equipment. In this study, we improve upon previously published bulk DNA extraction methods by reducing bench time and materials. Our results indicate that the addition of caffeine and RNase A improves DNA extraction, resulting in lower Cq values during real-time PCR while reducing the processing time and cost per specimen. Such improvements will enable the use of high throughput screening methods across multiple platforms to improve the probability of detection of H. armigera. [ABSTRACT FROM AUTHOR]