• BMB Reports
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• v.40 no.1
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• pp.65-71
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• 2007

The Helicoverpa armigera nucleopolyhedrovirus (HearNPV) ORF80 (ha80) has 765 bp encoding a protein with approximately 254 amino acids and a predicted molecular weight of 30.8 kDa. Homologues of ha80 are found in most baculovirus sequences, including those from lepidopteran NPVs, lepidopteran granuloviruses (GVs), hymenopteran baculoviruses, and one dipteran baculovirus, yet their functions remain unclear. In this study we characterized ha80, and showed that it was transcribed late in infected host cells (HzAM1). The product of ha80 was a 31 kDa protein that was not a structural protein of budded virus (BV) or occlusion-derived virus (ODV) particles. Ha80 was first detected in the cytoplasm of infected HzAM1 cells at 12 h p.i., and was observed in the nucleus at later stages of infection, suggesting that it may be involved in transporting viral proteins into the host cell nucleus or play its roles in the nucleus.

• BMB Reports
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• v.38 no.3
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• pp.354-359
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• 2005

Open reading frame 29 (ha29) is a gene specific for Helicoverpa armigera single-nucleocapsid nucleopolyhedrovirus (HearSNPV). Sequence analyses showed that the transcription factor Tfb2 motif, bromodomain and Half-A-TPR (HAT) repeat were present at aa 66-82, 4-76, 55-90 of the Ha29 protein respectively. The product of Ha29 was detected in HearSNPV-infected HzAM1 cells at 3 h post-infection. Western blot analysis using a polyclonal antibody produced by immunizing a rabbit with purified GST-Ha29 fusion protein indicates that Ha29 is an early gene. The size of Ha29 product in infected HzAM1 cells was about 25 kDa, which was larger than the presumed size of 20.4 kDa. Tunicamycin treatment of HearSNPV-infected HzAM1 cells suggested that the Ha29 protein is N-glycosylated. Fluorescent confocal laser scanning microscope examination, and Western blot analysis of purified budded virus (BVs), occlusion-derived virus (ODVs), cell nuclear and cytoplasmic fraction, showed that the Ha29 protein was localized in the nucleus. Our results suggested that ha29 of HearSNPV encodes a non-structurally functional protein that may be associated with virus gene transcription in Helicoverpa hosts.

• Journal of Applied Biological Chemistry
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• v.43 no.4
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• pp.222-229
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• 2000

In this paper we will assess the feasibility of some insect behavior-modifying chemicals for insect control, such as male orientation inhibitor, female calling interrupter and female attractant of cotton bollworm Helicoverpa armigera. These behavior-modifying chemicals have advantages of simple chemical structure, easy to synthesize and low price of products. The effects of sub-lethal insecticides on insect chemical communication system and the differences of pheromone communication systems between the resistant and susceptible strain of H. armigera will also be discussed.

• Current Research on Agriculture and Life Sciences
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• v.32 no.4
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• pp.185-188
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• 2014

The movement, survival, and weight gain of Helicoverpa armigera $H{\ddot{u}}bner$ (Lepidoptera: Noctuidae) first instar larvae were studied on CB9, CB10 and SR05 cotton varieties under field conditions. The neonate H. armigera were released on the cotton varieties at the squaring stage of the plants and, after a period of 72 hours, the survival, weight gain, and final location of the larvae were observed. While the different cotton varieties had no effect on the survival and weight gain of the larvae, the release locations on the cotton varieties had a significant influence on the larval survival and weight gain. The larvae fed small squares of the cotton varieties were significantly heavier and showed a higher mortality than the larvae fed leaflets and mature leaves. For the cotton varieties in this study, the larvae released on leaflets showed a significantly higher rate of recovery compared to the larvae released on mature leaves and squares. This study also found that that the larvae on leaflets did not move up or downward unlike the larvae on mature leaves and squares. This information on the foraging behavior of larvae on cotton varieties will assist researchers to interpret field data and thereby help with the development of pest management decisions.

• BMB Reports
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• v.39 no.3
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• pp.263-269
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• 2006

In the genome of Helicoverpa armigera single-nucleocapsid nucleopolyhedrovirus, open reading frame 39 (Ha39) is the only gene predicted to encode an RNA recognition protein. Computer analysis revealed that Ha39 homologues were found in 15 NPVs, but not in GVs. Its transcripts were detected from 3 through 72 hours post infection (h p.i.) using RT-PCR and Northern blot analysis. The protein was detected in infected-cell lysates from 6 h p.i. Western blot assay of ODV and BV preparations revealed that Ha39 encodes a structural protein associated with BVs. Additionally, immunofluorescence microscopy demonstrated that the protein was present within cytoplasm in virus-infected cells, but not in the nuclear region.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.393-400
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• 2010

The parasitism, development time, hatchability, and progeny production of Trichogramma chilonis(TC) females developed in eggs of Helicoverpa assulta (HAs), Cadra cautella (CC), and Helicoverpa armigera (HAr), respectively, were compared with those developed in reciprocal eggs at constant temperatures of $25{\pm}2^{\circ}C$ and relative humidity of 50~70% under 16L-8D. Developmental performances of TC reared in each of the three hosts on the following hosts(host tested) appeared differently, and were affected most by the size of the proceeding hosts and test host. Among the parameters parasitism and progeny production were affected more than others. Parasitism was significantly different between the treatments, lowest in CC-HAr($10.1{\pm}2.05%$) and highest in HAr-HAs($47.0{\pm}2.09%$), and the hatchability showed similar pattern. Development time as well was shortest in the CC-HAr where previous host is smallest and test host is biggest. The highest number of progeny production of TC was observed in HAr-HAs($93.9{\pm}6.87$ wasps), and the lowest was CC-HAs($18.4{\pm}6.36$ wasps).

• Journal of Microbiology and Biotechnology
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• v.23 no.11
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• pp.1536-1543
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• 2013

Proteases produced by Xenorhabdus are known to play a significant role in virulence leading to insect mortality. The present study was undertaken to purify and characterize protease from Xenorhabdus indica, an endosymbiont of nematode Steinernema thermophilum, and to decipher its role in insect mortality and its efficacy to control Helicoverpa armigera. A set of 10 strains of Xenorhabdus isolated from different regions of India were screened for protease activity on the basis of zone of clearing on gelatin agar plates. One potent strain of Xenorhabdus indica was selected for the production of protease, and the highest production (1,552 U/ml) was observed at 15-18 h of incubation at $28^{\circ}C$ in soya casein digest broth. The extracellular protease was purified from culture supernatant using ammonium sulfate precipitation and ion-exchange chromatography. The enzyme was further characterized by SDS-PAGE and zymography, which confirmed the purity of the protein and its molecular mass was found to be ~52 kDa. Further MALDI-TOF/TOF analysis and effect of metal chelating agent 1,10-phenanthrolin study revealed the nature of the purified protease as a secreted alkaline metalloprotease. The bioefficacy of the purified protease was also tested against cotton bollworm (Helicoverpa armigera) and resulted in $67.9{\pm}0.64%$ mortality within one week. This purified protease has the potential to be developed as a natural insecticidal agent against a broad range of agriculturally important insects.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.431-437
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• 2016

This study was carried out to investigate pests and their damage caused to commercial greenhouse strawberries in Jeju from 2013 to 2016. A total of 8 orders, including 31 species, of pests were found. Among them, the major pests were Tetranychus urticae, Frankliniella occidentalis, and Aphis gossypii. Although Trialeurodes packardi and Empoasca vitis were sometimes severely damaged strawberries, their frequency of occurrence and damage caused increased gradually. Of lepidopteran pests, Spodoptera litura showed the highest occurrence and damage. Although Helicoverpa armigera was showed a low occurrence frequency, it caused severe damage. We discussed the seasonal occurrence patterns of four pests-F. occidentalis, the alate A. gossypii, T. packardi and E. vitis-monitored by yellow-colored sticky traps.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.383-392
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• 2015

We investigated the induction of pupal diapause and number of generation for H. armigera using outdoor rearing and sex pheromone trapping in Suwon, Korea. Over-wintering pupae were induced when neonate larvae were reared in the outdoors from late Aug. to early Oct. in 2013 and 2014. H. armigera adults emerged from late May to early Jun. for 2013 colonies and from late May to late Jun. for 2014 colonies. The colonies placed after mid September produced only diapause pupae, to show environmental conditions that day-lengths on the rearing start date were 11 h 49 min~12 h 24 min, and mean temperatures before pupation were $14.8{\sim}20.7^{\circ}C$. Summer diapause was not observed in all colonies. The peak occurrence of H. armigera adults from sex pheromone trap in Suwon and Hwaseong were pooled and showed four generations (1st: from late Apr. to mid Jun., 2nd: from mid Jun. to late Jul., 3rd: from mid Jul. to late Aug., 4th: from late Aug. to mid Oct.). A degree-day model for development of H. armigera developed by Mironidis and Savopoulou-Soultani (2008) was used to validate the number of generation from field observations using pheromone traps. The 3rd and over-wintering generations were mainly overlapped. It was decided that H. armigera has one over-wintering and three complete generations in a year, and diapause is induced from offsprings of the 3rd and 4th generations adults. It is expected that larvae of the 1st and 2nd generations give a damage to ear zone in maize fields in which have been planted during April.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.1
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• pp.63-68
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• 2002

A cDNA encoding a putative member of cathepsin B of the thiol pretense superfamily was cloned from a cDNA library of the mulberry longicorn beetle, Apriona germari. Sequence analysis of the cDNA encoding the cathepsin B of A. germari (AgCatB) revealed that the 972 bp cDNA has an open reading frame of 324 amino acid residues. The deduced protein sequence of the AgCatB showed high homology with cathepsin B of the insects, Bombyx mori (47.3% amino acid identity), Helicoverpa armigera (46.6%) and Sarcophaga peregrina (45.6%), and the lowest homology with Aedes aegypti (33.2%). The AgCatB contains six disulfate bonds typical for cysteine pretenses. The three amino acid positions Cys-109, His-267, and Asn-287 which are conserved, active sites characteristic for cathepsin B, were also found. Phylogenetic analysis further confirmed that the AgCatB has a close relationship with that of B. mori, H. armigera and S. peregrina.