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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., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

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., (Published by Oxford University Press on behalf of Entomological Society of America 2019.)

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]

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]

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.

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]

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]

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]