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BACKGROUND: The Oriental tobacco budworm, Helicoverpa assulta, a specialist herbivorous insect that exclusively feeds on plants of the Solanaceae family, causes considerable damage to crops, such as tobacco and hot pepper. The absence of a genome sequence for this species hinders further research on its pest management and ecological adaptation. RESULTS: Here, we present a high‐quality chromosome‐level genome of a Korean strain of H. assulta (Pyeongchang strain, K18). The total assembly spans 424.4 Mb with an N50 length of 14.54 Mb and 37% GC content. The assembled genome (ASM2961881v1) comprises 31 chromosomes, similar to other congeneric generalist species including H. armigera and H. zea. In terms of genomic assembly quality, the complete BUSCOs and repeat content accounted for 98.3% and 33.01% of the genome, respectively. Based on this assembly, 19 485 protein‐coding genes were predicted in the genome annotation. A comparative analysis was conducted using the identified number of protein‐coding genes in H. armigera (24154) and H. zea (23696). Out of the 19 485 predicted genes, 137 genes in 15 orthogroups were found to have expanded significantly in H. assulta, while 149 genes in 95 orthogroups contracted rapidly. CONCLUSION: This study revealed specific gene expansions and contractions in H. assulta compared to those in its close relatives, indicating potential adaptations related to its specialized feeding habits. Also, the comparative genome analysis provides valuable insights for the integrated pest management of H. assulta and other globally significant pests in the Heliothinae subfamily. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Chickpeas are one of the most important pulse crop in the world, and production in Brazil is small, but ramping up. In regions where cultivation is recent, such as the state of Rio de Janeiro, it is important to evaluate the agronomic performance of different chickpea cultivars, their adaptability to edaphoclimatic conditions and phytosanitary aspects. Pests can vary from one location to another and pose risks to the crop. Caterpillars are the main pests of chickpea in Brazil and throughout the world. Thus, this work aims to evaluate the occurrence of caterpillars associated with chickpea culture in an experimental area, in the state of Rio de Janeiro, Brazil. Four chickpea cultivars were evaluated (BRS Aleppo, BRS Cícero, BRS Cristalino and BRS Toro), using randomized block distribution and four replications per treatment. The greatest rate of damaged pods occurred in the BRS Aleppo and BRS Cristalino cultivars with 62%, while BRS Toro showed 48% and BRS Cícero 25%. Two species of Lepidoptera identified as Chloridea virescens and Helicoverpa armigera (Lepidoptera: Noctuidae) were found attacking the chickpea pods (Lepidoptera: Noctuidae). Of these, 14 (64%) were C. virescens and eight (36%) were H. armigera. This is the first report of these two species in chickpeas in the state of Rio de Janeiro. [ABSTRACT FROM AUTHOR]

The South American bollworm, Helicoverpa gelotopoeon (Dyar), is a member of the Heliothinae complex in Northwestern Argentina and one of the most important pests affecting soybean in the country. Currently, management of Heliothinae pest species is based on the use of insecticides and transgenic Bt crops. However, many species in the Heliothinae complex have developed resistance to these control tactics. In this regard, studies of population structure and genetic diversity studies in these agricultural insect pests are of great importance for the effective implementation of management strategies. Mitochondrial DNA is one of the types of molecular markers available for insect studies successfully employed for population genetic studies in Lepidoptera. The aim of this study was to evaluate the genetic diversity and population structure of five H. gelotopoeon populations collected from different regions and crops in Argentina using analysis of three mitochondrial DNA regions. Results of genetic variability and gene flow analyses among H. gelotopoeon populations indicated, in general, a certain genetic structure in studied populations. Possible causes for this genetic structure include differences among regions, host plants and year of sampling. Additional studies contemplating the impact of biological and ecological features are necessary in understanding the source of genetic structure in these H. gelotopoeon populations. [ABSTRACT FROM AUTHOR]

Heliothine moths (Family Noctuidae : Subfamily Heliothinae) are ubiquitous crop pests with three documented species combinations known to hybridize: Helicoverpa zea x Helicoverpa armigera, H. armigera x Helicoverpa assulta, and Heliothis virescens x Heliothis subflexa. Hybrids can have advantageous traits, such as increased host range, resistance to insecticides, and increased mating success, posing serious threats to agriculture. However, deleterious traits of hybrids, such as developmental abnormalities or sterility, can be exploited for pest management. In this review, the characteristics of F1 hybrids and backcrosses are examined through a historical lens. Topics reviewed include developmental characteristics, sex pheromone synthesis and perception, mating and calling behavior, sperm morphology, gene expression, electrophysiological responses, structures of the central and peripheral nervous systems, hybrid sterility, and applications in pest control. Recommendations for future studies based on existing gaps of knowledge are given, as are proposed pest management strategies.

The tobacco budworm Chloridea (Heliothis) virescens (F.) (Lepidoptera: Noctuidae) has been recently reported in corn crops. However, there is no information regarding the biology of this species feeding on corn cobs. Additionally, the relationship between temperature and tobacco budworm feeding habits is important to project the adaptation of the insect in corn crops at different times and regions. This study aimed to investigate the development of C. virescens feeding on corn cobs, under controlled laboratory conditions, at three temperatures (25 ± 1 ºC, 28 ± 1 ºC and 31 ± 1 ºC). Although adult budworms were observed at all temperatures, the larval development period was reduced at 31 ± 1 ºC, resulting in a lower grain consumption. On the other hand, biological parameters such as larval and pupal viability, pupal weight and sex ratio did not vary with temperature. During the adult stage, a similar fecundity was recorded at all temperatures; however, the egg viability was zero. The optimal temperature for the C. virescens development was between 25 ± 1 ºC and 28 ± 1 ºC. The temperature of 31 ± 1 ºC affects the eggs development, preventing the next generation of tobacco budworms.

Biology and life table of Heliothis peltigera (Denis & Schiffermüller, 1775) (Lepidoptera: Noctuidae), an important safflower pest, studied on two safflower varieties (Balcı and Dinçer) in the laboratory (25 ± 1 °C temperature, 65 ± 5% relative humidity and 16: 8 photoperiod). The longer pre-adult time of H. peltigera was found on Dinçer variety than Balcı variety, as 33.97±0.16 days, and 32.82±0.23 days, respectively. While the higher intrinsic rate of increase (r) (0.134±4.59 d-1), and the finite rate of increase (λ) (1.144±0.005 d-1) were estimated on Balcı variety, also shortest mean generation times were found on Balcı variety (37.49±0.34 days) than Dinçer variety (0.119±5.123 d-1, 1.126±0.005 d-1, and 39.25±0.40 days, respectively). According to these results, it was determined that Balcı variety was more suitable host plants than Dinçer variety for H. peltigera. These basic informations obtained in this study on H. peltigera will be useful for pest control and prefer to produce Dinçer variety that could be reducing of H. peltigera. [ABSTRACT FROM AUTHOR]

Copyright of Agricultural Research in the Tropics / Pesquisa Agropecuária Tropical is the property of Pesquisa Agropecuaria Tropical 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.)

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 gelotopoeon (Dyar) (Lepidoptera: Noctuidae) is a polyphagous pest that has been reported causing damage in many agricultural crops such as soybean, chickpea and cotton. This species, together with Helicoverpa zea (Boddie), Helicoverpa armigera (Hübner) and Chloridea virescens (Fabricius), belongs to the Heliothinae complex of economic importance in Northwestern Argentina.Many species in the Heliothinae subfamily have developed resistance to insecticides and insecticidal proteins from Bacillus thuringiensis (Bt). Managing resistance to these control tactics in H. gelotopoeon is of high importance and dependant on knowledge of population genetics of this species.The objective of this study was to evaluate the genetic variability and structure of H. gelotopoeon populations from different host plants and geographic regions of Argentina. Towards this goal, six microsatellite loci were screened across 196 individuals.The results obtained revealed high genetic diversity and lack of clear structure among the populations of H. gelotopoeon studied. This genetic homogeneity between populations from different geographical regions and hosts could be attributed to the long‐range migratory capacity of Heliothinae and the generalist behaviour of H. gelotopoeon. [ABSTRACT FROM AUTHOR]

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]

ABSTRACT: Helicoverpa armigera (Hübner) regularly requires quick deployment of control practices due to its potential of causing yield loss of processing tomatoes. The monitoring of H. armigera adults using stick traps lured with sex pheromone was correlated to egg densities, larvae, and percentage of damaged fruits, aiming to subsidize control decisions only using the number of males caught in the traps since surveying pest stages or damaged fruits is laborious and costly. Surveys were carried out on 11 tomato fields (ca. 80 to 120 hectares each) for processing during the 2015 and 2016 crop seasons. The survey was initiated at the flowering stage with traps set up along the field borders 100 m distant each. Evaluations of adult male capture in the traps were conducted twice a week for 14 and 10 weeks during the 2015 and 2016 seasons, respectively. Simultaneously, 70 tomato plants were fully inspected for eggs, larvae, and damaged fruits per area using a rate of 10 plants per point of trap setting in each area. Overall capture of male moths correlated to subsequent eggs, larvae, and damaged fruits. Based on the outcome of the regression analysis between male moths captured and percentage of damaged fruits, the control decision is suggested when three to six male moths are captured per trap during one week. The monitoring of adults using pheromone traps help deploy chemical or biological control methods to restrain H. armigera population reaching economic threshold levels.

Tomato plants host various herbivores, including the Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), recently introduced into South and Central America. It is a harmful pest for tomato crops, damaging mainly the flowers and fruits. The assessment of losses and the establishment of economic injury level (EIL) and economic threshold (ET) are core steps toward establishing a control program. We determined losses caused by H. armigera on processing tomato and estimated EIL/ET values. Trials were run during two growing seasons using tomato plants caged in the field. The field cage experiment consisted of six densities of H. armigera second instar larvae (0, 1, 3, 6, 12, and 24 larvae per row meter) at two infestations periods spaced 15 d apart with the first infestation done 90 d after transplanting. The larvae were placed individually on the third upper fully developed leaf. The number of healthy and damaged fruits, size, and weight of the fruits were measured. Yield losses as a function of infestation of 1–24 larvae per row meter ranged from 4 to 34% and resulted in a yield reduction of 1.22–12.77 kg per row meter. The EIL ranged from 1.41 to 1.72 and from 2.11 to 2.58 larvae per row meter of plants in 2017 and 2018 cropping seasons, respectively. Helicoverpa armigera causes significant reduction of tomato yield. These EIL values will enable better control decision-making in processing tomato. [ABSTRACT FROM AUTHOR]

Helicoverpa armigera (Hübner) is part of an important complex of insects-pests that attack the cotton crop. This study aimed to identify the preferential plant parts for the oviposition of moths, as well as the movement and feeding behavior of caterpillars, in the vegetative phase of the cotton cultivar BRS 369 RF. Plants emitting floral buds were used to study the oviposition behavior of moths. For this, a completely randomized design, with three treatments (adaxial and abaxial sides of the leaf and floral buds) and twenty replications (plants in pots), was used. In order to evaluate the behavior of the caterpillars in the cotton vegetative phase, another 3 × 5 factorial design, with nine replications, was used. The treatments were three ages (first, second and third instars) combined with five behaviors (walking, resting, waving, eating and drop-off). In this trial, the period of the day when caterpillars are more active was also evaluated. It was observed that H. armigera moths prefer to lay their eggs on the adaxial leaf side and on the last two nodes of the plant, in a descending direction. The adaxial leaf side is also the part of the plant preferred by caterpillars for walking, eating and resting, being this last behavior the most frequent in all instars. In general, the caterpillars walk more in the morning.

A soja está sujeita ao ataque da lagarta Helicoverpa armigera durante todo seu ciclo. Quando na fase inicial, pode comprometer o estabelecimento da cultura no campo. Esse estudo teve por objetivo avaliar os danos da lagarta em plântulas de soja, para isso, utilizou-se o delineamento experimental em blocos casualizados com cinco repetições. Os tratamentos foram cinco níveis de infestação: 0, 7, 14, 21 e 28 lagartas m-2. A infestação ocorreu no estádio fenológico cotiledonar (VC) utilizando lagartas de quinto ínstar, e, durante três dias, foram avaliados os danos causados nas hastes, cotilédones e folhas unifolioladas. Já ao final do experimento avaliou-se a altura de plantas, a biomassa e o estande final. Houve danos nas três estruturas vegetativas avaliadas e, em geral, o aumento da população do inseto promoveu aumento no nível de danos, reduzindo o estande, a altura e a biomassa das plântulas de soja. Conclui-se que a lagarta H. armigera causa danos severos às plântulas de soja, o que pode afetar o estabelecimento inicial da cultura.

In Egypt There are 16 subfamilies belonging to family Noctuidae. We have previously dealt with the subfamily: Xyleninae and in this study, we are exposed to revise six subfamilies which are Acronictinae, Heliothinae, Metoponiinae, Noctuinae, Oncocnemidinae, and Plusiinae. These subfamilies contain 27 genera contain 65 species. Subfamily Noctuinae is the most representative subfamily with 33 species under 7 genera, while subfamily Acronictinae is the smallest subfamily containing only two species under one species. [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]

Soybean plants are susceptible to the attack of Helicoverpa armigera caterpillars throughout their cycle, including during early developmental stages, which can compromise their settling in the field. This study aimed to assess the damage caused by caterpillars to soybean seedlings. A randomized block design with five replicates was used and the treatments consisted of five levels of infestation: 0, 7, 14, 21 and 28 caterpillars/m-2. The infestation occurred in the cotyledon stage (VC), using fifth instar caterpillars. For three days, all damage caused to the stem, cotyledon, and unifoliates was evaluated. By the end of the experiment, seedling height, biomass, and the final stand value were determined. Damage was observed in the three vegetative structures and, in general, increase in insect population promoted higher levels of damage, reducing stand, height, and biomass of seedlings significantly. Thus, H. armigera caterpillars cause severe damage to soybean seedlings, which may affect their early establishment. [ABSTRACT FROM AUTHOR]

Resumo: O objetivo deste trabalho foi avaliar o desempenho de inseticidas autorizados emergencialmente para o controle de Helicoverpa armigera (Lepidoptera: Noctuidae) em soja. Sete inseticidas foram pulverizados em campo e, após 24 horas, folhas do ponteiro foram coletadas e oferecidas para lagartas de 2o instar em laboratório. Lagartas do 4o instar receberam a última folha trifoliolada que se encontrava completamente expandida no momento da pulverização. Outro grupo foi exposto a folhas coletadas a partir de 72 horas da pulverização. Em campo, seis inseticidas foram pulverizados e, em seguida, as plantas foram infestadas com lagartas de 2o e 3o instar. No primeiro estudo, flubendiamida, clorantraniliprole, clorfenapir, indoxacarbe e metoxifenozida causaram 100% de mortalidade do 4o instar aos oito dias após o início da exposição, enquanto baculovírus e Bacillus thuringiensis (Bt) propiciaram mortalidade de 60-75%, que evoluiu para 88-90% ao final da fase de pupa. Para o 2o instar, apenas flubendiamida e clorantraniliprole proporcionaram mortalidade de 100%. Flubendiamida, clorantraniliprole e clorfenapir apresentaram o menor tempo letal para o 4o instar, e flubendiamida e clorantraniliprole, para o 2o instar. Após 72 horas da pulverização, o desempenho dos inseticidas foi insatisfatório. Em campo, houve eficiência satisfatória de flubendiamida, espinosade, baculovírus e Bt sobre lagartas de 2o e 3o instar.

This study aimed to evaluate the larval biology of Heliothis virescens in soybean MON 87701 x MON 89788 and its isogenic non-Bt. In general, the impact of soybean MON 87701 x MON 89788 on H. virescens was evidenced in all bioassays, 100% larval mortality, independent of the structure (leaf or pod) consumed by the pest. The small larvae (1st and 3rdinstar) demonstrated that they were unable to damage fresh pods of soybean, regardless of whether Bt or not Bt. The large larvae (5th instar) fed on soybean MON 87701 x MON 89788 soybeans consumed three times less compared to larvae fed on non-Bt soybeans, and resulted in reduced longevity and larval survival. When soybean plants were infested with 5th instar larvae, H. virescens caused injuries in the steams of the conventional soybean. It was recorded that the insects moves quickly to this region of the plant. However the soybean MON 87701 x MON 89788 was an effective tool in controlling H. virescens.

The occurrence of Helicoverpa armigera (Hübner, 1808) was first reported in citrus orchard in the state of São Paulo (SP). High infestation levels of H. armigera were observed in October 2012, in the city of Botucatu, SP. The larvae was fed of all parts of the plants. The injuries on the leaves caused drastic reduction in the leaf area and the fruits attack occurred from an early stage of development to the ripe fruit. Thus, the first occurrence of H. armigera in this citrus culture adds to the list of hosts of this pest, and is of great importance, because it confirms H. armigera potential dispersion and polyphagia.

In 2013, the presence of Helicoverpa armigera (Hübner) was reported in cotton, soybean, corn and weeds in diverse regions of Brazil. We studied the biology and the fertility life table of this pest when reared on cotton (293 cv. CNPA RF), soybean (cv. Brasmax Power), corn (cv. BRS 1010), wheat (cv. BR 18) and on an artificial diet. Caterpillars were reared using the vegetative and reproductive structures of the hosts, under laboratory conditions (temperature 25 ± 1°C; relative humidity (RH) 70± 10%; photoperiod =14 h). The experimental design was completely randomized,with five treatments (four host plants and artificial diet) and 17 replications. Significant effects were verified for the different types of hosts tested on the growth of the insect as well as on fecundity and laying rate. The results showed that cotton and soybean had higher viability at the stages of growth, higher rate of survival of adult females in the reproductive period than the other host crops, and similar values for insects reared on an artificial diet, which reveals that cotton and soybean can be appropriate for rearing H. armigera on a natural diet. Corn and wheat showed high larval and pupal mortality and low biotic potential. [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]

In intensive soybean cropping systems, early-season pest insects such as lepidopteran larvae can seriously compromise crop establishment. Using a polyphagous global pest ̶ ̶ the Old World bollworm Helicoverpa armigera (Lepidoptera: Noctuidae), we determined the potential of seed treatments with diamide or neonicotinoid-carbamate mixture for systemic plant protection and residual efficacy against noctuid larvae. In controlled edaphoclimatic conditions, we infested differently aged soybean plants and recorded plant damage and insect mortality, growth, development, and fecundity to assess lethal and sublethal post-exposure effects. The seed treatments reduced plant damage by 50% during 1–7 days after plant emergence. The lowest damage (<25% defoliation) occurred on plants treated with chlorantraniliprole or cyantraniliprole. These diamides caused larval mortality >80% until 14 days after soybean emergence, which was the window of residual control efficacy. Carbofuran or thiodicarb + imidacloprid caused less than 50% larval mortality and minor plant protection against the larvae. There were sublethal effects on the growth, development, and fecundity of the insects surviving on plants of the insecticide seed treatments. The diamide seed treatments reduced the overall insect fitness for a longer time after plant emergence than did the other treatments. Therefore, soybean seed treatment with chlorantraniliprole or cyantraniliprole is potentially efficacious against noctuid larvae in the VE–V1 soybean growth stages (emergence until the first trifoliate), causing lethal and sublethal effects on the insects. Judicious use and effective resistance management for these systemic compounds are relevant as they are helpful for seed treatment and foliar applications against diverse targets. Helicoverpa armigera can compromise soybean crop establishment in intensive systems. Soybean seed treatment with chlorantraniliprole or cyantraniliprole is potentially efficacious against noctuid larvae in the first 14 days (VE-–V1 soybean growth stages), causing lethal and sublethal effects on the insects. [Display omitted] • Helicoverpa armigera can compromise soybean crop establishment in intensive systems. • Insecticide seed coating was studied for protection and residual control of H. armigera. • Damage was lowest on plants treated with chlorantraniliprole or cyantraniliprole (diamides). • Diamides had >80% efficacy for 14 d; imidacloprid + thiodicarb or carbofuran did not. • (Sub)lethal effects reduced the insect fitness; the diamides suppressed population growth. [ABSTRACT FROM AUTHOR]

In this study is reported the first occurrence, in Brazil, of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), which was considered up till now a quarantine pest. The notification occurred in the Goiás State, in soybean; Bahia State, in volunteer soybean; and Mato Grosso State, in cotton.

Chloridea subflexa and Chloridea virescens are a pair of closely related noctuid species exhibiting pheromone-based sexual isolation and divergent host plant preferences. We produced a novel Illumina short read C. subflexa genome assembly and an improved C. virescens genome assembly, which offer opportunities to study the genomic basis for evolutionarily important traits in this lepidopteran family with few genomic resources. We then examined the feasibility of reference-assisted assembly, an approach that leverages existing high quality genomic resources for genome improvement in closely related taxa and applied it to our Heliothine genomes. Our work demonstrates that reference-assisted assembly has the potential to enhance contiguity and completeness of existing insect genomic resources with minimal additional laboratory costs. We conclude by discussing both the potential and pitfalls of reference-assisted assembly according to the intended downstream assembly application. • We produced an updated, highly contiguous Chloridea virescens assembly and a novel Chloridea subflexa short read assembly. • Reference-assisted assembly improved newly generated and publicly available short read Heliothine genome assemblies. • Genome contiguity and completeness are enhanced by reference-assisted assembly without added costs of experimental finishing. • Gaps may be introduced into the target assembly if the reference assemblies are low quality or from distantly related taxa. [ABSTRACT FROM AUTHOR]

Copyright of Agricultural Research in the Tropics / Pesquisa Agropecuária Tropical is the property of Pesquisa Agropecuaria Tropical 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.)

Theory and recent literature suggest strong effects of induced plant defences in some plant herbivore systems. Few have studied behavioural effects on intact plants. Differences in foraging behaviour as well as weight gain were determined for first instar Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) on Arabidopsis thaliana (L.) Heynh. (Brassicaceae) mutant and wild type plants, non-primed, or primed by herbivore feeding or methyl jasmonate. The differences in feeding were primarily in the length of feeding time as opposed to the area fed on, feeding location, or frequency. More larvae dispersed from plants after priming by mite feeding than dispersed after caterpillar feeding. Other behavioural activities such as resting were not significantly affected. Early instars gained less weight feeding on ein2 (ethylene insensitive) mutant, but there was no difference in weight gain between larvae feeding on induced and non-induced plants of the same type. We concluded that there are fitness consequences for neonates of the generalist H. armigera after feeding on induced plant tissues in some cases, and that distinct changes in behaviour are recognisable both at the fine scale and at grosser levels (dispersal). However, these changes are more subtle than might be expected. [ABSTRACT FROM AUTHOR]

A little-known lepidopteran, Aedophron eos Varga & L. Ronkay, 1991, is recorded in China for the first time. Adults and male genitalia of the species are illustrated. [ABSTRACT FROM AUTHOR]

Seven desaturase cDNAs were isolated from pheromone glands of Helicoverpa assulta, a moth producing a sex pheromone blend with high Z9-16:Ald and low Z11-16:Ald, opposite to what is found in other heliothine moths such as Helicoverpa zea. Six of the seven sequences map onto recently defined lepidopteran desaturase sequence lineages and the other is orthologous to a desaturase sequence previously reported only in H. zea. The levels of desaturase-encoding transcripts in pheromone glands were determined and the three most abundant ones were functionally expressed in a desaturase-deficient mutant strain of Saccharomyces cerevisiae. The HassNPVE transcript, shown to encode a Δ9 desaturase producing more Z9-18:Acid than Z9-16:Acid, was the most abundant, followed by the HassKPSE transcript, shown to encode a Δ9 desaturase producing more Z9-16:Acid than Z9-18:Acid, and by the HassLPAQ transcript, shown to encode a Δ11 desaturase producing only Z11-16:Acid. Thus, the relative amounts of transcripts encoding two Δ9 desaturases and a single Δ11 desaturase in H. assulta pheromone glands were consistent with the relative amounts of unsaturated fatty acid precursors required to produce the major and minor sex pheromone components of this species. Desaturase transcript levels in pheromone glands were also found to be as high during scotophase as during light phase, when pheromone production ceases. The other four transcripts were present at extremely low levels in H. assulta pheromone glands and the functional roles of their encoded desaturase-homologous proteins could not be determined. [Copyright &y& Elsevier]

Molecular phylogenetic analysis was conducted using conserved cytoplasmic actin and diversified cytochrome P450 (P450) sequences isolated from Helicoverpa zea and Helicoverpa armigera, two species thought to be closely related based on allozyme analyses. These sequences were compared in turn with published sequences from other insects to gain insight into how different gene families evolve. In Bombyx mori and these Helicoverpa species, cytoplasmic actin genes are present as a pair of tandemly duplicated paralogs with coding sequence identities as high as 95.5% (B. mori), 98.9% (H. zea) and 98.5% (H. armigera) due to recent 5′-polar gene conversions. Phylogeny and interspecies comparisons assign the six actin genes into two orthologous groups: HaA3a/HzA3a/BmA3 and HaA3b/HzA3b/BmA4, which exhibit more similarities between H. zea and H. armigera than between Helicoverpa species and B. mori. Like the actin genes in H. zea, four CYP6B genes exist as two pairs of duplicated paralogs with recent 5′-polar gene conversions. Interspecific comparisons and phylogeny analysis identified three groups of orthologous CYP6B genes: H. zea CYP6B8 or CYP6B28/H. armigera CYP6B7, H. zea CYP6B27/H. armigera CYP6B6, and H. zea CYP6B9/H. armigera CYP6B2/Heliothis virescens CYP6B10. The low degree of divergence in the first two of these groups is comparable to allelic variation within a single species. These orthologous relationships and the high degrees of similarity in both actin and P450 genes strongly indicate that these Helicoverpa species are extremely closely related. [Copyright &y& Elsevier]

Australothis volatilis sp. n., the only species of Heliothinae endemic to New Zealand, is described. The larval food plants, Vittadinia spp., are recorded and other biological information is provided. The male and female genitalia, penultimate and final instar larva, pupa, adult, native food plant, and habitat are illustrated. [ABSTRACT FROM AUTHOR]