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Sample records for heliothis armigera hubner

  1. The use of 65Zn in the study of Heliothis armigera larva's behavior on tomatoes

    Saour, George.

    1987-01-01

    Short communication. A summary of a DEA report submitted under the title ''Etude au moyen du Zinc Radioactif 65 Zn du comportement des chenilles d'Heliothis armigera hubner (Lepidoptera, Noctuidae) sur Tomate.'' Univ. de Droit d'Economie et des Sciences d'Aix-Marseille-III. Faculte des Sciences et Techniques de Saint-Jerome. INRA-MONTEAVET, Station de Zoologie

  2. Trichogramma chilotraeae PARASITOID TELUR Helicoverpa armigera (Hubner PADA POPULASI INANG RENDAH

    - Sujak

    2011-03-01

    Full Text Available Helicoverpa armigera Hubner is an insect pest of corn and cotton crops. Eggs are laid by  H. armigera imago on corn silk and cotton crops often have high mortality, mainly caused by egg parasitoid. H. armigera egg on various agroecosystem reported can  be parasited by at least 12 species of  Trichogrammatidae. The purpose of this study was to determine the diversity of  Trichogrammatidae family as  parasitoid eggs of  H. armigera on  low population. H. armigera egg sample taken from Asembagus, Lamongan and Blora at 1 m2 field  both monoculture and intercropping. Observation of parasitoids and predators  done at the Laboratory of Biological Control Balittas Malang. Parasitoid that appears preserved in the Hoyer medium for identification purposes. low population of  H. armigera Egg in Asembagus is  4 eggs/m2 in both monoculture maize and intercropping with 86-100 days after transplanting (DAT cotton and  4.5 egg/m2 on cotton monoculture and intercropping with 75  DAT soybean, while 2 eggs/m2 in the Lamongan and Blora corn agroecosystem. The dominant egg parasitoid in Asembagus is T. chilotraea, as well as in Lamongan and Blora.

  3. LABORATORY AND FIELD EVALUATION OF ESSENTIAL OILS FROM Cymbopogon nardus AS OVIPOSITION DETERRENT AND OVICIDAL ACTIVITIES AGAINST Helicoverpa armigera Hubner ON CHILI PEPPER

    Wiwin Setiawati

    2011-04-01

    Full Text Available The fruit borer (Helicoverpa armigera Hubner is one of the key pests of chili pepper in Indonesia. Yield loss due to this insect pest may reach up to 60%. Chemical treatment for con-trolling this insect pest is ineffective and eventually leads to environmental pollution. More environmentally safe insecticides are developed based on natural plant ingredients as their active compound such as essential oils. This study aimed to assess the potential of citronella oil for managing H. armigera on chili pepper. The experiments were conducted at the Indonesian Vegetables Research Institute from April 2009 to March 2010 and in Cirebon, West Java from November 2009 to March 2010. A field experiment was designed in a randomized complete block design with five treatments and replicated five times. Citronella oil was extracted by steam distillation from Cymbo-pogon  nardus. The oil was then chemically characterized by using GC-MS and its efficacy (ovicidal and feeding deterrent against H. armigera was tested both in laboratory and field conditions. The GC-MS result showed that major chemical compounds of the citronella oil used were citronella (35.97%, nerol (17.28%, citronellol (10.03%, geranyle acetate (4.44%, elemol (4.38%, limonene (3.98%, and citronnellyle acetate (3.51%. The laboratory experiment revealed that the highest concentration (4,000 ppm of citronella oil reduced egg laying by 53-66%. Ovicidal activity was concentration dependent, and egg hatchability decreased by 15-95% compared to control. The field experiment showed that treatment of citronella oil at 2.0 mL L-1 significantly reduced fruit damage by H. armigera similar to the plots treated with spinosad at the recommended dose (60 g ai ha-1. Application of citronella oil significantly reduced fruit damage by 72% and increased quality of the chili pepper. Because oviposition and feeding deterrent properties are key factors in controlling the pest, therefore this study revealed that

  4. Tarsal taste neuron activity and proboscis extension reflex in response to sugars and amino acids in Helicoverpa armigera (Hubner).

    Zhang, Yun-Feng; van Loon, Joop J A; Wang, Chen-Zhu

    2010-08-15

    In adult female Helicoverpa armigera (Hübner), the fifth tarsomere of the prothoracic legs bears 14 gustatory trichoid chemosensilla. These chemosensilla were characterized through electrophysiological experiments by stimulating with sucrose, glucose, fructose, maltose, myo-inositol and 20 common amino acids. In electrophysiological recordings from nine sensilla, responses were obtained to certain compounds tested at 100 mmol l(-1), and the response spectra differed from broad to narrow. The four sugars excited the same receptor neuron in sensillum a and sensillum b; sucrose and myo-inositol, sucrose and lysine, myo-inositol and lysine excited two different receptor neurons respectively in sensillum a; fructose and lysine excited two different receptor neurons in sensillum n. Furthermore, the four sugars, myo-inositol and lysine all elicited concentration-dependent electrophysiological responses. These six compounds also induced the proboscis extension reflex (PER) followed by ingestion of the solution when they were applied on the tarsi. Lysine and sucrose caused the strongest electrophysiological responses. However, sucrose had the strongest stimulatory effect on the PER whereas lysine had the weakest. Mixtures of sucrose with the other sugars or with lysine had a similar stimulatory effect on the PER as sucrose alone. The electrophysiological and behavioural responses caused by a range of sucrose concentrations were positively correlated. We conclude that the tarsal gustatory sensilla play an essential role in perceiving sugars available in floral nectar and provide chemosensory information determining feeding behaviour. Tarsal taste-receptor-neuron responses to lysine are implicated in oviposition behaviour.

  5. Perspective of using the sterile insect technique for Tobacco Budworms Heliothis virescens (Lepidoptera: Noctuidae) and Cotton Bollworm Helicoverpa armigera (Lepidoptera: Noctuidae) in cotton crop as an alternative method of control

    Haddad, Gianni Queiroz

    2017-01-01

    Since the 1950s, scientists have used ionizing radiation to sterilize insects, which are released in nature to mate, but without any progeny. Known as the sterile insect technique (TIE), this method of insect control has traditionally used ionizing radiation to sterilize insects, a technique that does not generate residues, and can act in synergy with the other techniques within integrated pest management. For several years, Brazil has been fighting against the increase of pests, introducing new tactics and techniques within the IPM programs, to overcome the resistance of chemical products, such as: reducing the residues of agrochemicals; For some important crops of our country, we have a wide spectrum of pests occurring from the beginning to the end of the harvest, one of them is the cotton crop and among the key pests of this crop, we have some extremely important caterpillars, among them Heliothis virescens and Helicoverpa armigera These species are morphologically similar, the second being identified a few years ago in Brazil. There are still no studies in Brazil using TIE as an additional tool for Lepidoptera, therefore the purpose of this study was to evaluate the effect of doses of gamma radiation in the different phases of the evolutionary cycle of Heliothis virescens and Helicoverpa armigera, as well as to evaluate the sterility in generation P And the ability of insects to irradiate with non-irradiated insects. The pupal phase presented the best result because 75 Gy achieved sterility in Heliothis virecens and 100 Gy sterilized Helicoverpa armigera, therefore it contemplated the phase and dose chosen to evaluate the competition between the irradiated insects and the normal insects of both species. Both Heliothis virecens and Helicoverpa armigera presented a satisfactory result, as the irradiated insects managed to significantly reduce the viability of the eggs in a ratio of 9: 1: 1. (author)

  6. Perspective of using the sterile insect technique for Tobacco Budworms Heliothis virescens (Lepidoptera: Noctuidae) and Cotton Bollworm Helicoverpa armigera (Lepidoptera: Noctuidae) in cotton crop as an alternative method of control; Perspectiva de utilizacao da Tecnica do Inseto Esteril para lagarta da maca Heliothis virescens (Lepidoptera: Noctuidae) e lagarta do velho mundo Helicoverpa armigera (Lepidoptera: Noctuidae) na cultura do algodoeiro como um metodo alternativo de controle

    Haddad, Gianni Queiroz

    2017-07-01

    Since the 1950s, scientists have used ionizing radiation to sterilize insects, which are released in nature to mate, but without any progeny. Known as the sterile insect technique (TIE), this method of insect control has traditionally used ionizing radiation to sterilize insects, a technique that does not generate residues, and can act in synergy with the other techniques within integrated pest management. For several years, Brazil has been fighting against the increase of pests, introducing new tactics and techniques within the IPM programs, to overcome the resistance of chemical products, such as: reducing the residues of agrochemicals; For some important crops of our country, we have a wide spectrum of pests occurring from the beginning to the end of the harvest, one of them is the cotton crop and among the key pests of this crop, we have some extremely important caterpillars, among them Heliothis virescens and Helicoverpa armigera These species are morphologically similar, the second being identified a few years ago in Brazil. There are still no studies in Brazil using TIE as an additional tool for Lepidoptera, therefore the purpose of this study was to evaluate the effect of doses of gamma radiation in the different phases of the evolutionary cycle of Heliothis virescens and Helicoverpa armigera, as well as to evaluate the sterility in generation P And the ability of insects to irradiate with non-irradiated insects. The pupal phase presented the best result because 75 Gy achieved sterility in Heliothis virecens and 100 Gy sterilized Helicoverpa armigera, therefore it contemplated the phase and dose chosen to evaluate the competition between the irradiated insects and the normal insects of both species. Both Heliothis virecens and Helicoverpa armigera presented a satisfactory result, as the irradiated insects managed to significantly reduce the viability of the eggs in a ratio of 9: 1: 1. (author)

  7. Assessment of Lupin Induced Mutants for Quality Traits and Susceptibility to Callosbruchus chinensis and Heliothis armigera insects

    Ragab, A.I.; Boshra, S.A.; Mehany, A.L.; Darwish, A.A.; Kharrab, M.M.

    2008-01-01

    This study was conducted to assess 23 induced mutants and two parental varieties Giza1 and Giza2 in the three generations (M3, M4, and M5) for seed quality traits, and susceptibility to two insects i.e C. chinnensis and H.armigera. The obtained results exhibited highly significant decrease for alkaloid content of mutants 20 and 23 as compared with the two local varieties. Most of mutants and Giza 2 showed marked increase for protein content as compared with Giza1, however, the increase did not reach the level of significance for the most mutants as compared with Giza2 in the three generations. Except of M4 generation. marked resistance for infestations with C.chinensis and H.armigera was obtained for mutants 1, 5 and 11 in the three generations. However, for total infestation with the two insects, resistance was obtained in mutants 4 and 10. Except of mutant lines 1, 5 and 11, all mutants showed higher loss percentage than that of the local varieties

  8. Hybridization between Helicoverpa armigera and Helicoverpa assulta (Lepidoptera: Noctuidae): development and morphological characterization of F1 hybrids

    Zhao, X.C.; Dong, J.F.; Tang, Q.B.; Yan, Q.B.; Celbic, I.; Loon, van J.J.A.; Wang, C.Z.

    2005-01-01

    Reciprocal hybridizations between Helicoverpa armigera (Hubner) and Helicoverpa assulta (Guenee) were studied. The cross between females of H. armigera and males of H. assulta yielded only fertile males and sterile individuals lacking an aedeagus, valva or ostium bursae. A total of 492 larvae of the

  9. Expression of a Chimeric Gene Encoding Insecticidal Crystal Protein Cry1Aabc of Bacillus thuringiensis in Chickpea (Cicer arietinum L.) Confers Resistance to Gram Pod Borer (Helicoverpa armigera Hubner.).

    Das, Alok; Datta, Subhojit; Thakur, Shallu; Shukla, Alok; Ansari, Jamal; Sujayanand, G K; Chaturvedi, Sushil K; Kumar, P A; Singh, N P

    2017-01-01

    Domain swapping and generation of chimeric insecticidal crystal protein is an emerging area of insect pest management. The lepidopteran insect pest, gram pod borer ( Helicoverpa armigera H.) wreaks havoc to chickpea crop affecting production. Lepidopteran insects were reported to be controlled by Bt ( cryI ) genes. We designed a plant codon optimized chimeric Bt gene ( cry1Aabc ) using three domains from three different cry1A genes (domains I, II, and III from cry1Aa , cry1Ab , and cry1Ac , respectively) and expressed it under the control of a constitutive promoter in chickpea ( cv . DCP92-3) to assess its effect on gram pod borer. A total of six transgenic chickpea shoots were established by grafting into mature fertile plants. The in vitro regenerated (organogenetic) shoots were selected based on antibiotic kanamycin monosulfate (100 mg/L) with transformation efficiency of 0.076%. Three transgenic events were extensively studied based on gene expression pattern and insect mortality across generations. Protein expression in pod walls, immature seeds and leaves (pre- and post-flowering) were estimated and expression in pre-flowering stage was found higher than that of post-flowering. Analysis for the stable integration, expression and insect mortality (detached leaf and whole plant bioassay) led to identification of efficacious transgenic chickpea lines. The chimeric cry1Aabc expressed in chickpea is effective against gram pod borer and generated events can be utilized in transgenic breeding program.

  10. Expression of a Chimeric Gene Encoding Insecticidal Crystal Protein Cry1Aabc of Bacillus thuringiensis in Chickpea (Cicer arietinum L. Confers Resistance to Gram Pod Borer (Helicoverpa armigera Hubner.

    Alok Das

    2017-08-01

    Full Text Available Domain swapping and generation of chimeric insecticidal crystal protein is an emerging area of insect pest management. The lepidopteran insect pest, gram pod borer (Helicoverpa armigera H. wreaks havoc to chickpea crop affecting production. Lepidopteran insects were reported to be controlled by Bt (cryI genes. We designed a plant codon optimized chimeric Bt gene (cry1Aabc using three domains from three different cry1A genes (domains I, II, and III from cry1Aa, cry1Ab, and cry1Ac, respectively and expressed it under the control of a constitutive promoter in chickpea (cv. DCP92-3 to assess its effect on gram pod borer. A total of six transgenic chickpea shoots were established by grafting into mature fertile plants. The in vitro regenerated (organogenetic shoots were selected based on antibiotic kanamycin monosulfate (100 mg/L with transformation efficiency of 0.076%. Three transgenic events were extensively studied based on gene expression pattern and insect mortality across generations. Protein expression in pod walls, immature seeds and leaves (pre- and post-flowering were estimated and expression in pre-flowering stage was found higher than that of post-flowering. Analysis for the stable integration, expression and insect mortality (detached leaf and whole plant bioassay led to identification of efficacious transgenic chickpea lines. The chimeric cry1Aabc expressed in chickpea is effective against gram pod borer and generated events can be utilized in transgenic breeding program.

  11. The influence of the temperature at the intensity of the spread of the cotton bollworm (heliothis obsoleta fabr. = helicoverpa armigera hb.) as a pest of the peppers in the Strumica region

    Spasov, Dusan; Spasova, Dragica; Ilievski, Mite; Atanasova, Biljana

    2015-01-01

    H. armigera is typical polyphagous insect which attacks: tomatoes, peppers, tobacco, maize, cotton, garlic, onions, cabbage, soy, beans and many other leguminous and pumpkin crops and various weed plants. The damages from the cotton bollworm have economic importance, especially when the species is in progradation. It is widespread all over the world, especially in warmer climates. The increase in the population of this cotton bollworm is associated with global warming.

  12. Natural control of Helicoverpa armigera in smallholder crops in East Africa

    Berg, van den H.

    1993-01-01

    The African bollworm, Helicoverpa (=Heliothis) armigera , is one of the worst agricultural pests in Africa, attacking a variety of food and cash crops. For development of sustainable pest management, it is essential to study the ecology and natural

  13. Sterilization of Helicoverpa armigera (hubner) moth (lepidoptera; Noctudae) by using Gamma rays radiation

    Subiyakto; Wari D Astati; Sunarto Dwi A

    1998-01-01

    This experiment was conducted at the Radiation Facility, National Atomic Energy, Jakarta and Entomology Laboratory of the Research Institute for Tobacco and Crops Malang in 1991. Sterilization of moth by radiating insect on pupae stage. The dosage were 0 (unradiated), 1,3,5,7,9,11,13,and 15 krad. The treatments were arranged in complete randomized design with three replications. Each treatments were made variation of copulation (1) two females radiated with a make unradiated (2) two females unradiated with a male radiated, and (3) two females radiated with a male radiated. The results showed that sub sterile dosage (LD 50 ) for male was 0.94 krad and 7.02 krad for female. The sterile dosage (LD 95 ) for male was 10.85 krad and 14.35 krad for female. Research of the competition for copulation between the male radiated and unradiated is needed. (author)

  14. Анализ этологических и репродуктивных особенностей и динамики развития популяции Heliothis armigera на протяжении сезона

    Валерия КЕПТИНАРЬ

    2017-06-01

    Full Text Available Information on the fertility of female cotton bollworms and the viability of their laid eggs makes it possible to predict the number of next generation in the crop fields and the harm that this population may cause to the harvest. During the vegetative season of 2016 (the 1st decade of May - the 3rd decade of September, a seasonal monitoring of the Heliothis armigera pest population was carried out using a light trap installed in the immediate vicinity of a soybean field. Due to the conducted research, the emergence and peaks of the cotton bollworm flight were recorded, sex ratio wes determined, as well as reproductive and copulative potential of females were estimated. It was established that in the climatic conditions of the Republic of Moldova, Heliothis armigera pest develops in three generations. The duration of generation development is from the 3rd decade of May to the 3rd decade of September. Male-female ratio was 58% males to 42% females. The copulative and reproductive potential of this pest depends on the succession of generations. The reproductive potential of the first generation was 37.8%, 40.1% for the second generation and 22.1% for the third generation. The copulative potential of H. armigera females was of 65.0% paired 1-2 times and only 35.0% were paired 3-5 times. Реферат. Сведения о плодовитости самок хлопковой совки и жизнеспособности отложенных ими яиц предоставляет возможность прогнозировать численность последующего поколения на участках сельскохозяйственных культур и ту опасность, которую эта популяция нанесет урожаю. На протяжении вегетативного сезона 2016 года (Iдекада мая – III декада сентября был проведен

  15. Cytogenetic estimation of inheritable partial sterility induced by γ-radiation in bollworm heliothis armigera hubn

    Sajfutdinov, B.N.

    1989-01-01

    Translocations have bveen counted in meiosis of the progeny of bollworm moths γ-irradiatied with doses of 50, 75 and 100 Gy: they amounted to 0.53, 1.93 and 4.02 per insect, and frequency of the insects with translocations to 0.44, 0.88 and 0.98, respectively

  16. Use of radiation induction to improve new cotton lines resistant to Heliothis armigera

    Hormchan, P [Dept. of Entomology, Faculty of Agriculture, Kasetsart Univ., Bangkok (Thailand); Wongpiyasatid, A [Dept. of Applied and Isotopes Faculty fo Science, Kasetsart Univ., Bangkok (Thailand)

    1996-12-01

    Ratchada 1 (R{sub 1}) seeds irradiated with 300 gray of gamma rays in order to obtain new cotton lines resistant to the American bollworm with high yield and good quality were compared with Srisamrong 2 (SR{sub 1}) and Ratchada 1 (R{sub 1}), the present recommended varieties to the farmers. The experiments were conducted under both laboratory and field conditions for 3 consecutive years and 2 new lines, A P{sub 1} and A P{sub 2} in M{sub 5} with the required attribute, were finally selected. In the lab, after feeding 2 nd instar bollworm larvae with young leaves of tested lines and the controls the increased weight, larval length, pupal weight of new lines were found to be better than those of SR{sub 2} and R{sub 1} including % gossypol and flavonoids, the substances being expected to give antibiotic effect to the insects. Physical aberration was also noticed in A P{sub 1}. As of the field condition, with the similar amount of bollworm numbers, the 10 fresh boll weight, lint weight, seed weight, % lint, micronaire fibre strength, and fibre length were found to be higher and better than those of both controls as well. However, further tests in large scale of farmers` field a period of time will have to be undertaken to ascertain the result

  17. Radiation Induced F-1 Sterility For The Control Of Cotton Bollworm , Helicoverpa armigera (Huebner) In Pilot Test

    Segsarnviriya, Suchada; Pransopon, Prapon; Kongratarpon, Titima; Vongcheeree, Satit

    2005-10-01

    Pilot trials of radiation induced F-1 sterility for the control of cotton bollworm Helicoverpa armigera (Hubner) were studied for 3 cotton crop seasons in 3 locations at Amphor Takfa, Nakornsawan province in 2002, 2003 and 2004. Irradiated male pupae at a sub sterilizing dose of 150 Gy were released : approximately 11,170 42,900 and 36,400 pupae from July to December of 2002, 2003 and 2004, respectively. The insecticide plots were maintained as a comparison to determine the efficiency of this method. Checking of larvae on cotton plants by the systematic random sampling method and the cotton yield were used to evaluate the impact of the pupal release. It was found that the releasing plots and the insecticide plots gave similar results in terms of the number of larvae and the cotton yield. Therefore, the F-1 sterility method was a possible method for the control of cotton bollworm

  18. Insecticidal Efficacy of Azadirachta indica, Nucleopolyhedrovirus and Chlorantraniliprole Singly or Combined against Field Populations fo Helicoverpa armigera Hübner (Lepidoptera: Noctuidae Eficacia Insecticida de Azadirachta indica, Nucleopolihedrovirus y Clorantraniliprol solo y sus Aplicaciones Integradas contra Poblaciones de Campo de Helicoverpa armigera Hübner (Lepidoptera: Noctuidae

    Waqas Wakil

    2012-03-01

    Full Text Available The development of resistance in cosmopolitan insect Helicoverpa armigera Hubner (Lepidoptera: Noctuidae forced the researchers for alternative control measures. In the present study, insecticidal efficacy of formulations of Azadirachta indica, a Nucleopolyhedrovirus (NPV, and new anthranilic diamide insecticide (chlorantraniliprole formulations was determined against 2nd, through 5th larval instars of H. armigera collected from diverse geographical locations in the Punjab province, Pakistan. Azadirachta indica was applied at 5 μL L-1; NPV at 2.1 x 10(5 polyhedral occlusion bodies (POB mL4 and chlorantraniliprole at 0.01 μL L-1, either alone or in combinations with each other. The bioassays were conducted at 27 ± 1 °C and 65 ± 5% relative humidity. The mortality varied greatly among treatments, larval instars, and locations. The combinations of NPV with A. indica and chlorantraniliprole caused higher mortality, pupation and produced an additive effect compared to their application singly in all the tested populations. The population from Rawalpindi was always susceptible while the Gujranwala was the resistant. The results herein suggest that the effectiveness of NPV and A. indica can be improved by the presence of chlorantraniliprole against the larvae of H. armigera.Se determinó la eficacia insecticida de formulaciones de Azadirachta indica, Nucleopolihedrovirus (VPN y el nuevo insecticida diamida antranílico (clorantraniliprol en contra de segundo, tercero, cuarto y quinto estadios larvales de Helicoverpa armigera Hubner (Lepidoptera: Noctuidae recogidos de diversas ubicaciones geográficas de la provincia de Punjab, Pakistán. Azadirachta indica se aplicó en dosis de 5 μL L-1; VPN en dosis 2.1 x 10(5 POB mL-1 y clorantraniliprol fue 0,01 μL L-1 ya sea solos o en combinaciones. Los bioensayos se realizaron a 27 ± 1 °C y 65 ± 5% de humedad relativa. La mortalidad fue notablemente variada entre los tratamientos, estadios larvales y

  19. Human radiation studies: Remembering the early years. Oral history of hematologist Karl F. Hubner, M.D., December 30, 1994

    1995-09-01

    This report is a transcript of an interview of Dr. Karl F. Hubner by representatives of the US DOE Human Radiation Experiments. Dr. Hubner was selected for this interview because of his participation in the Oak Ridge Institute of Nuclear Studies(ORINS)/Oak Ridge Associated Universities(ORAU) Medical Division cancer therapy research program involving total body irradiation. After a short biographical sketch Dr. Hubner discusses his research in Bone Marrow Transplants, his participation in the development of Nuclear Medicine in Oak Ridge, use of the total body irradiation machine at the University of Tennessee School of Agriculture Animal Research Laboratory (later the Comparative Animal Research Laboratory or CARL) to deliver a high enough dose rate to destroy a patients immune system, the operation of a sterile environment for recovery of patients following bone- marrow transplantation, and the closing of the ORAU Medical Division's Clinical Program following a negative review. Finally, Dr. Hubner describes his later research using PET

  20. Current status of backcross sterility in Heliothis virescens (F.)

    Hardee, D.D.; Laster, M.L.

    1996-01-01

    Because of insecticide resistance, high cost of controls and the need to reduce pesticide use, attempts have been made to manage Heliothis virescens with non-insecticidal techniques. One such approach has been the use of sterile male interspecific hybrids produced from crosses between males of H. virescens and females of H. subflexa

  1. The preliminary studies on parasitization of Trichogramma chilonis on Helicoverpa armigera eggs and eggs from irradiated Helicoverpa armigera moths

    Wang Endong; Lu Daguang; Liu Xiaohui; Li Yongjun; Zhang Shuyong; Liu Qiongru; Wang Huasong

    2002-01-01

    The parasitization rates of Trichogramma chilonis on 250 Gy irradiated and unirradiated fresh eggs of cotton bollworm, Helicoverpa armigera, were not significantly different. The parasitization rate on irradiated chill-stored eggs of H. armigera was lower than that on irradiated fresh eggs. The parasitization rates on eggs from 250 Gy irradiated H. armigera moths depended on their embryonated rates

  2. Sterilization studies on the adult indian meal moth, plodia interpunctella (HUBNER)

    Boshra, S.A.; Hasaballa, Z.A.

    1993-01-01

    The effects of gamma radiation doses ranging between 10 and 65 krad on adult plodia interpunctella (Hubner) were studied. Irradiation of adult affected clearly the egg production and fertility of both sexes at different mating combinations. Females were more sensitive to the sterilizing effects of gamma radiation than males. Complete sterility of females and males was achieved at 50 and 65 krad, respectively. Replacing normal males by sterile ones in the normal population decreased the egg hatch ability when compared with the control population. Newly emerged unmated females laid completely infertile eggs when confined with irradiated (65 krad) males, whether mating occurred on the day of treatment or 2 days after treatment. Sterilized males were able to compete with normal ones in a population at the highest flooding ratios. Adding sterile females to this competing population gave excellent results.5 tab

  3. Emamectin benzoate: new insecticide against Helicoverpa armigera.

    Fanigliulo, A; Sacchetti, M

    2008-01-01

    Emamectin benzoate is a new insecticide of Syngenta Crop Protection, with a new mechanism of action and a strong activity against Lepidoptera as well as with and a high selectivity on useful organisms. This molecule acts if swallowed and has some contact action. It penetrates leaf tissues (translaminar activity) and forms a reservoir within the leaf. The mechanism of action is unique in the panorama of insecticides. In facts, it inhibits muscle contraction, causing a continuous flow of chlorine ions in the GABA and H-Glutamate receptor sites. During 2006 and 2007, experimentation was performed by the Bioagritest test facility, according to EPPO guidelines and Principles of Good Experimental Practice (GEP), aiming at establishing the biological efficacy and the selectivity of Emamectin benzoate on industry tomato against Helicoverpa armigera (Lepidoptera: Noctuidoe). The study was performed in Tursi-Policoro (Matera), southern Italy. Experimental design consisted in random blocks, in 4 repetitions. A dosage of 1.5 Kg/ha of the formulate was compared with two commercial formulates: Spinosad 0.2 kg/ha (Laser, Dow Agrosciences Italia) and Indoxacarb 0.125 kg/ha (Steward EC insecticide, Dupont). Three foliage applications were applied every 8 days. The severity of damage induced by H. armigera was evaluated on fruits. Eventual phytotoxic effects were also evaluated. Climatic conditions were optimal for Lepidoptera development, so that the percentage of fruits attacked in 2007 at the first scouting was 68.28%. Emamectin benzoate has shown, in two years of testing, a high control of H. armigera if compared with the standards Indoxacarb and Spinosad. No effect of phytotoxicity was noticed on fruits.

  4. Ocorrência de Serratia marcescens bizio sobre lagartas de Heliothis virescens (Fabr. Occurrence of Serratia marcescens bizio on Heliothis virescens (Fabr.

    Margarida Fumiko Ito

    1996-01-01

    Full Text Available Observou-se, em laboratório, grande número de lagartas mortas em uma criação de Heliothis virescens (Fabr.. Dessas lagartas, isolou-se uma bactéria, posteriormente identificada como Serratia marcescens Bizio. O presente trabalho registra sua ocorrência e comprova-lhe a patogenicidade sobre aquelas lagartas.A large quantity of dead worms was observed in rearing of Heliothis virescens. A bacteria, later identified as Serratia marcescens Bizio, was isolated from the dead worms. The present work registers the occurrence and confirms the pathogenicity of S. marcescens on H. virescens.

  5. Radio-induced inherited sterility in Heliothis zea (Boddie)

    Carpenter, J.E.

    1985-01-01

    Heliothis zea (Boddie) (Lepidoptera: Noctuidae) males and females were irradiated with substerilizing doses of radiation. These moths were inbred and outcrossed and observed for their ability to reproduce. The inherited deleterious effects resulting from the irradiated P 1 males were recorded for several generations. Larvae from both irradiated (10 krad) and normal parents were compared for their ability to survive under field conditions on whole-stage sweet corn and these results were compared with those from a laboratory study using meridic diet. Irradiated males and females and F 1 males from an irradiated (10 krad) male x normal female cross were released in the field and in field cages and observed for their ability to search/attract and secure a mate. Females that had mated with normal and irradiated (10 krad) males were studied to determine the effect of different mating histories on the subsequent mating propensity of the females. A 10-krad dose of radiation induced deleterious effects which were inherited through the F 2 generation. These radiation-induced deleterious effects were similar to those reported in other species of Lepidoptera. The relationship between the survival of normal larvae and larvae from irradiated parents was similar under laboratory and field rearing conditions. Females mated to normal males and males irradiated with 10 krad had the same mating propensity and experienced the same intermating interval. These effects of substerilizing doses of radiation and inherited sterility on the reproductive ability and behavior of H. zea suggest that a great potential exists for population suppression

  6. Evaluation of acetone vapors toxicity on Plodia interpunctella (Hubner) (Lepidoptera: Pyralidae) eggs.

    Pourmirza, Ali Asghr; Nasab, Fershteh Sadeghi; Zadeh, Abas Hossein

    2007-08-01

    The efficacy of acetone vapors against carefully aged eggs of Plodia interpunctella (Hubner) at 17+/-1 and 27+/-1 degrees C at different dosage levels of acetone over various exposure times was determined. Acetone was found to be toxic to Indian meal moth eggs. Considerable variation in the susceptibility of different age groups of eggs was apparent in the fiducial limits of the LD50 values. An inverse relationship between LD50 values and exposure times was observed in age groups of tested eggs. At 27+/-1 degrees C and 24 h exposure period, eggs aged 1-2 day-old were more tolerant to acetone than other age groups, followed by 0-1 day-old, 2-3 day-old and 3-4 day-old eggs. A similar pattern of susceptibility of eggs was observed at 72 h exposure. In all bioassays, eggs exposed to higher dosages of acetone developed at smaller rate. This was significant for the eggs, which were exposed to the highest dosage for 24 h. Increasing the temperature from 17+/-1 to 27+/-1 degrees C greatly increased the efficacy of acetone. At 27+/-1 degrees C eggs of P. interpunctella were killed by less than one-third of the dosage required for control at 17+/-1 degrees C. Acetone achieved 50% mortality with a dosage of 82.76 mg L(-1) in 1-2 day-old eggs at 27+/-1 degrees C. At this temperature hatching was retarded and greatly diminished when eggs aged 1-2 day-old were exposed to 80 mg L(-1) of acetone for the 24 h exposure period. There was no evidence of a hatch delay longer than the time spent under vapors for eggs exposed at 17+/-1 or 27+/-1 degrees C, indicating that some development must have occurred under fumigation.

  7. Host plant specialization in the generalist moth Heliothis virescens and the role of egg imprinting

    Karpinski, A.; Haenniger, S.; Schöfl, G.; Heckel, D.G.; Groot, A.T.

    2014-01-01

    Even though generalist insects are able to feed on many different host plants, local specialization may occur, which could lead to genetic differentiation. In this paper we assessed the level and extent of host plant specialization in the generalist herbivore Heliothis virescens Fabricius

  8. Genetic differentiation across North America in the generalist moth Heliothis virescens and the specialist H. subflexa

    Groot, A.T.; Classen, A.; Inglis, O.; Blanco, C.A.; López Jr., J.; Vargas, A.T.; Schal, C.; Heckel, D.G.; Schöfl, G.

    2011-01-01

    The two moth species Heliothis virescens (Hv) and H. subflexa (Hs) are closely related, but have vastly different feeding habits. Hv is a generalist and an important pest in many crops in the USA, while Hs is a specialist feeding only on plants in the genus Physalis. In this study, we conducted a

  9. The sequence of the Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus genome

    Chen, X.; IJkel, W.F.J.; Tarchini, R.; Sun, X.; Sandbrink, H.; Wang, H.; Peters, S.; Zuidema, D.; Klein Lankhorst, R.; Vlak, J.M.; Hu, Z.

    2001-01-01

    The nucleotide sequence of the Helicoverpa armigera single-nucleocapsid nucleopolyhedrovirus (HaSNPV) DNA genome was determined and analysed. The circular genome encompasses 131 403 bp, has a G C content of 39.1 molnd contains five homologous regions with a unique pattern of repeats.

  10. Immune responses of Helicoverpa armigera to different kinds of pathogens

    Zhao Xiao-Fan

    2010-03-01

    Full Text Available Abstract Background Insects react against pathogens through innate immunity. The cotton bollworm Helicoverpa armigera (H. armigera is an important defoliator and an extremely destructive pest insect of many crops. The elucidation of the mechanism of the immune response of H. armigera to various pathogens can provide a theoretical basis for new approaches to biologically control this pest. Results Four kinds of pathogens Bacillus thuringiensis, Klebsiella pneumoniae, Candida albicans, and Autographa californica multiple nucleocapsid nucleopolyhedrovirus harbored green fluorescence protein and polyhedron (AcMNPV-GFP were used to challenge the insect. The cellular and humoral immune responses to the pathogens were analyzed in the challenged H. armigera. The results show that in the five kinds of haemocytes, only granulocytes phagocytized the Gram-negative and Gram-positive bacteria and fungi. All haemocytes can be infected by AcMNPV. Fourteen immune-related genes including pattern recognition receptors (PRRs such as peptidoglycan recognition proteins (HaPGRP and HaPGRP C and Gram-Negative Bacteria-Binding Protein (HaGNBP, and antimicrobial peptides (AMPs such as cecropin-1, 2 and 3 (HaCec-1, 2 and 3, lysozyme (HaLys, attacin (HaAtt, gallerimycin-like (HaGall, gloverin-like (HaGlo, moricin-like (HaMor, cobatoxin-like (HaCob, galiomicin-like (HaGali, and immune inducible protein (HaIip appeared in different expression profiles to different pathogen infections. The transcripts of 13 immune related genes (except HaPGRPC are obviously up-regulated by Gram-positive bacteria. HaCec-1 and 3, HaMor, HaAtt, HaLys, HaIip, HaPGRP and HaGNBP are greatly up-regulated after fungal infection. HaGNBP, HaCec-2, HaGall, HaGlo, HaMor, HaCob, HaGali obviously increased in Gram-negative bacterial infection. Only five genes, HaGNBP, HaCec-1, HaGali, HaGlo, and HaLys, are weakly up-regulated after viral infection. The AMP transcripts had higher expression levels than the

  11. Bollworm responses to release of genetically modified Helicoverpa armigera nucleopolyhedroviruses in cotton

    Sun, X.; Chen, X.; Zhang, Z.; Wang, H.; Bianchi, F.J.J.A.; Peng, H.; Vlak, J.M.; Hu, Z.

    2002-01-01

    Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus (HaSNPV) has been developed as a commercial biopesticide to control the cotton bollworm, H. armigera, in China. The major limitation to a broader application of this virus has been the relative long time to incapacitate the target insect.

  12. Field inactivation of wild-type and genetically modified Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus in cotton

    Sun, X.; Sun, X.C.; Werf, van der W.; Vlak, J.M.; Hu, Z.H.

    2004-01-01

    Cotton bollworm (Helicoverpa armigera) is a serious pest on cotton in China. A specific baculovirus, H. armigera nucleopolyhedroviruses (HaSNPV) is used as a commercial biopesticide to control this pest. To improve the pesticidal properties, HaSNPV has been genetically engineered by both deleting

  13. Sunlight stability and rain-fastness of formulations of Baculovirus heliothis

    Ignoffo, C.M.; Garcia, C.; Saathoff, S.G.

    1997-01-01

    Sunlight-Ultraviolet, with an activity spectrum from 290 to 400 nm, is the most destructive factor affecting the persistence of baculoviruses. Benzopurpurin (a disazo dye) and carbon provided the best protection when polyhedral inclusion bodies (PIB) of Baculovirus heliothis were exposed to an artificial spectrum simulating sunlight-UV (UV). Greater than 75% of the original PIB activity was still present after 48 h of sunlight-UV. When sprayed on soybeans and exposed to natural sunlight, only formulations with carbon provided significant protection of PIB. The half-life of formulations were PIB-only 4.9 +/- 1.4 h (mean +/- SE), PIB + polymer (pyrrolidone-based sticker) 3.3 +/- 0.6 h, PIB + polymer + benzopurpurin 3.4 +/- 0.7 h, and PIB + polymer + carbon 27.7 +/- 5.2 h. PIB of B. heliothis tenaciously adhere to soybean, Glycine max (L.) Merrill, leaflets after spraying and drying. Less than 6% of the PIB activity of nonformulated PIB was lost after a drenching, simulated rainfall. More than 97% of the original PIB activity of carbon formulations was still present on soybean leaflets after 10 h of exposure to sunlight-UV. In contrast, 20% was present for formulations without carbon

  14. The potential distribution of invading Helicoverpa armigera in North America: is it just a matter of time?

    Darren J Kriticos

    Full Text Available Helicoverpa armigera has recently invaded South and Central America, and appears to be spreading rapidly. We update a previously developed potential distribution model to highlight the global invasion threat, with emphasis on the risks to the United States. The continued range expansion of H. armigera in Central America is likely to change the invasion threat it poses to North America qualitatively, making natural dispersal from either the Caribbean islands or Mexico feasible. To characterise the threat posed by H. armigera, we collated the value of the major host crops in the United States growing within its modelled potential range, including that area where it could expand its range during favourable seasons. We found that the annual value of crops that would be exposed to H. armigera totalled approximately US$78 billion p.a., with US$843 million p.a. worth growing in climates that are optimal for the pest. Elsewhere, H. armigera has developed broad-spectrum pesticide resistance; meaning that if it invades the United States, protecting these crops from significant production impacts could be challenging. It may be cost-effective to undertake pre-emptive biosecurity activities such as slowing the spread of H. armigera throughout the Americas, improving the system for detecting H. armigera, and methods for rapid identification, especially distinguishing between H. armigera, H. zea and potential H. armigera x H. zea hybrids. Developing biological control programs, especially using inundative techniques with entomopathogens and parasitoids could slow the spread of H. armigera, and reduce selective pressure for pesticide resistance. The rapid spread of H. armigera through South America into Central America suggests that its spread into North America is a matter of time. The likely natural dispersal routes preclude aggressive incursion responses, emphasizing the value of preparatory communication with agricultural producers in areas suitable for

  15. Characterization of the metabolic transformation of thiamethoxam to clothianidin in Helicoverpa armigera larvae by SPE combined UPLC-MS/MS and its relationship with the toxicity of thiamethoxam to Helicoverpa armigera larvae.

    Fan, Yinjun; Shi, Xueyan

    2017-09-01

    In order to characterize the metabolic transformation of thiamethoxam (TMX) to clothianidin (CLO) in Helicoverpa armigera larvae and clarify its relationship with the insecticidal toxicity of TMX, method for determination of TMX and its metabolite clothianidin (CLO) residues in H. armigera larvae by solid phase extraction (SPE) combined UPLC-MS/MS was established. Following acetonitrile extraction and purification by SPE on florisil cartridge and C 18 cartridge sequently, and cleanup by PSA adsorption, TMX and CLO residues in H. armigera larvae were successfully determined by UPLC-MS/MS. By using the established method, the concentration-time curves of TMX and its metabolite CLO in H. armigera larvae in vivo and metabolism of TMX by microsome of H. armigera larvae midguts in vitro were studied. TMX was quickly eliminated from H. armigera larvae with the elimination half-life as 4.2h. Meanwhile, only a small amount of CLO was formed from TMX metabolism, with the maximum CLO level in H. armigera larvae only accounts for the metabolic transformation of 7.99% of TMX, at 10h after intravenous TMX administration. Our results suggested that the low insecticidal efficacy of TMX against H. armigera larvae was related with the rapidly elimination of TMX from H. armigera larvae, meanwhile, CLO as TMX metabolite at a very low level in vivo didn't contribute to TMX toxicity to H. armigera larvae. In H. armigera larvae, TMX didn't act as proinsecticide for CLO in insecticidal efficacy of TMX. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. A droplet digital PCR (ddPCR) assay to detect Helicoverpa armigera (Lepidoptera: Noctuidae) in bulk trap samples

    Moths in the genus Helicoverpa are some of the most important agricultural pests in the world. Two species, H. armigera (Hübner) and H. zea (Boddie), cause the majority of damage to crops and millions of dollars are spent annually on control of these pests. The recent introduction of H. armigera int...

  17. Keanekaragaman spesies parasitoid telur Helicoverpa armigera (Hübner pada sistem tanam monokultur dan polikultur kapas

    nurindah nurindah

    2017-02-01

    Full Text Available Polyculture system is one of techniques in pest management. In Indonesia, cotton is always intercropped with second food crops such as maize, soybean, mungbean or peanut. This research was aimed to evaluate the effect of culture system, i.e. cotton monoculture vs. cotton intercropped with soybean on the increase of species diversity of H. armigera egg parasitoids and the parasitoid contribution to mortality of H. armigera. The research was arranged in a split plot design with two main factors: three cotton varieties with three levels of trichome density (Tamcot SP 37, Kanesia 8 and LRA 5166 and the subplots were two cultivation systems (cotton monoculture and polyculture, with three replicates. Observations were made by collecting H. armigera eggs on population of first generation (45 days after planting and second generation (75 DAP. The results showed that on cotton polyculture the egg parasitoid complex which consisted of Trichogramma spp. and Trichogrammatoidea spp. was higher than that in cotton monoculture and so was the egg parasitism level. The increase of egg parasitism was 24% in the first generation and 15% in the second generation. Parasitoid species found belonged to the genera Trichogramma and Trichogrammatoidea. In the parasitoid complex, Trichogrammatoidea armigera was dominant on the first generation and Trichogramma chilotraeae on the second. The domination succession could be as a result of the higher host-searching capacity of T. chilotraeae than that of T. armigera.

  18. Performance of Helicoverpa armigera (Hübner (Lepidoptera: Noctuidae larvae in different food sources

    Crislaine Sartori Suzana

    2015-12-01

    Full Text Available Recently observed in Brazil, Helicoverpa armigera became a relevant pest due to its rapid spread and the economic importance of crops in which it has established, such as soybean and maize. Understanding its establishment process in different regions and production systems, as well as the population dynamics of a polyphagous pest, as the basis for its management, depends on the knowledge of the effect of plant species as food sources on the pest biology. A laboratory experiment was conducted, supplying the caterpillars with reproductive organs of soybean, maize, canola, black oat, oat, turnip and ryegrass. It was concluded that the different food sources affect the larval development of H. armigera. Maize and wheat ears and canola siliques are the best food sources for the development of H. armigera. Ryegrass ears, on the other hand, are the worst ones. Black oat and oat panicles and turnip siliques are less suitable than soybean pods as food sources for the caterpillars.

  19. The entomopathogenic fungus Nomuraea rileyi impairs cellular immunity of its host Helicoverpa armigera.

    Zhong, Ke; Liu, Zhan-Chi; Wang, Jia-Lin; Liu, Xu-Sheng

    2017-09-01

    In this study, we investigated the effect of the entomopathogenic fungus Nomuraea rileyi on Helicoverpa armigera cellular immune responses. Nomuraea rileyi infection had no effect on total hemocyte count (THC), but impaired hemocyte-mediated phagocytosis, nodulation, and encapsulation responses. Nomuraea rileyi infection led to a significant reduction in hemocyte spreading. An in vitro assay revealed that plasma from N. rileyi infected H. armigera larvae suppressed the spreading ability of hemocytes from naïve larvae. We infer that N. rileyi suppresses the cellular immune response of its host, possibly by secreting exogenous, cytotoxic compounds into the host's hemolymph. © 2017 Wiley Periodicals, Inc.

  20. A single gene (yes controls pigmentation of eyes and scales in Heliothis virescens

    Thomas M. Brown

    2001-02-01

    Full Text Available A yellow-eyed mutant was discovered in a strain of Heliothis virescens, the tobacco budworm, that already exhibited a mutation for yellow scale, y. We investigated the inheritance of these visible mutations as candidate markers for transgenesis. Yellow eye was controlled by a single, recessive, autosomal factor, the same type of inheritance previously known for y. Presence of the recombinant mutants with yellow scales with wild type eyes in test crosses indicated independent segregation of genes for these traits. The recombinant class with wild type scales and yellow eyes was completely absent and there was a corresponding increase of the double mutant parental class having yellow scales and yellow eyes. These results indicated that a single factor for yellow eye also controls yellow scales independently of y. This gene was named yes, for yellow eye and scale. We hypothesize that yes controls both eye and scale color through a deficiency in transport of pigment precursors in both the ommochrome and melanin pathways. The unlinked gene y likely controls an enzyme affecting the melanin pathway only. Both y and yes segregated independently of AceIn, acetylcholinesterase insensitivity, and sodium channel hscp, which are genes related to insecticide resistance.

  1. Sperm Production and Mating Ability Among F1 males of Heliothis Virescens (F.)

    Ibrahim, S.M.; Sallam, H.A.

    2000-01-01

    Adult males of Heliothis Virescens (F.) less than 12 h-old were irradiated with sub sterilizing doses of 50,100 or 125 Gy then crossed with untreated virgin females. The resulted F 1 males 1-and 4-day-old were dissected to determine the production of eupyrene sperm bundles and its accumulation in the duplex region. In another test, an experiment was conducted to determine the ability of F 1 males to mate and transfer sperm to untreated females. The data show that, eupyrene sperm bundles were not found in the duplex of newly emerged males immediately after emergence Number of eupyrene sperm bundles descended to duplex was significantly affected at 125 Gy during the first dark: light cycle of sperm descended. Accumulation of eupyrene sperm bundles of unmated F 1 males was significantly reduced at 100 and 125 Gy. It is apparent that the first mating is the most important, even in the control, and the rate of females that achieved successful mating with F 1 males after the first ejaculate was markedly reduced. This reduction was directly related to the dose level of irradiation. The proportion of mated females without and sperm, with apyrene sperms only or those with reduced amount of eupyrene sperms was generally increased as the dose applied to P 1 increased

  2. Genomic sequence of Heliothis virescens ascovirus 3g isolated from Spodoptera exigua.

    Huang, Guo-Hua; Wang, Yun-Sheng; Wang, Xing; Garretson, Tyler A; Dai, Liang-Ying; Zhang, Chuan-Xi; Cheng, Xiao-Wen

    2012-11-01

    Heliothis virescens ascovirus 3a (HvAV-3a), a member of the family Ascoviridae, has the highest diversity among ascovirus species that have been reported in Australia, Indonesia, China, and the United States. To understand the diversity and origin of this important ascovirus, the complete genome of the HvAV Indonesia strain (HvAV-3g), isolated from Spodoptera exigua, was determined to be 199,721 bp, with a G+C content of 45.9%. Therefore, HvAV-3g has the largest genome among the reported ascovirus genomes to date. There are 194 predicted open reading frames (ORFs) encoding proteins of 50 or more amino acid residues. In comparison to HvAV-3e reported from Australia, HvAV-3g has all the ORFs in HvAV-3e with 6 additional ORFs unique to HvAV-3g, including 1 peptidase C26 gene with the highest identity to Drosophila spp. and 2 gas vesicle protein U (GvpU) genes with identities to Bacillus megaterium. The five unique homologous regions (hrs) and 25 baculovirus repeat ORFs (bro) of HvAV-3g are highly variable.

  3. Antiviral activity against human immunodeficiency virus-1 in vitro by myristoylated-peptide from Heliothis virescens

    Ourth, Donald D.

    2004-01-01

    An insect antiviral compound was purified from Heliothis virescens larval hemolymph by gel-filtration high pressure liquid chromatography (HPLC) and C-18 reverse-phase HPLC and its structure was determined by mass spectrometry. The antiviral compound is an N-myristoylated-peptide containing six amino acids with calculated molecular weight of 916 Da. The N-terminus contains the fatty acid myristoyl, and the C-terminus contains histidine with two methyl groups giving the histidine a permanent positive charge. The remainder of the compound is essentially non-polar. The structure of the compound corresponds with the 'myristate plus basic' motif expressed by certain viral proteins in their binding to the cytoplasmic side of the plasma membrane to initiate viral assembly and budding from a host cell. The insect antiviral compound may inhibit viral assembly and/or budding of viruses from host cells that could include the human immunodeficiency virus-1 (HIV-1) and herpes simplex virus-1 that use this motif for exit from a host cell. Using the formazan assay, the myristoylated-peptide was effective against HIV-1, with a nine times increase in the viability and protection in vitro of treated CEM-SS cells when compared with infected but untreated control cells

  4. SUSCETIBILIDADE DE Helicoverpa armigera Hübner A FORMULADOS À BASE DE Bacillus thuringiensis BERLINER

    Victor Luiz de Souza Lima

    2017-01-01

    Full Text Available O inseto Helicoverpa armigera recentemente registrado no Brasil é uma das maiores pragas da agricultura mundial. Pode atacar mais de 200 espécies de plantas e possui populações resistentes a diversos inseticidas. A utilização de microrganismos com potencial patogênico contra insetos é uma alternativa aos inseticidas. Essa pesquisa foi realizada com o objetivo de determinar a suscetibilidade de lagartas de H. armigera à produtos formulados à base de Bacillus thuringiensis (Bt Para os experimentos, foram utilizados os produtos comerciais Dipel® e Agree®, os quais tiveram sua concentração ajustada para 108 conídios viáveis ml-1. Essa concentração foi aplicada sobre dieta artificial, a qual foi colocada em uma placa de Petri que continha 10 lagartas de primeiro instar. Foram realizadas cinco repetições para cada produto. As avaliações foram feitas a cada 24h durante sete dias. Os produtos comerciais Dipel® e Agree® causaram, respectivamente, 100% e 94% de mortalidade das lagartas de H. armigera. Esse resultado mostra o potencial de produtos à base de Bt sobre H. armigera.

  5. X-ray radiation and development inhibition of Helicoverpa armigera Hübner (Lepidoptera: Noctuidae)

    Kim, Junheon; Jung, Soon-Oh; Jang, Sin Ae; Kim, Jeongmin; Park, Chung Gyoo

    2015-01-01

    Effect of X-ray radiation on the development inhibition was evaluated for all stages of the life cycle of Helicoverpa armigera to determine a radiation dose for potential quarantine treatment against the insect. ED 99 values for inhibition of hatching, pupation, and adult emergence from irradiated eggs were 413, 210, and 154 Gy, respectively. ED 99 values for inhibition of pupation and adult emergence from irradiated larvae were 221 and 167 Gy, respectively. Pupa was the most tolerant to X-ray radiation. ED 99 value for inhibition of adult emergence from irradiated pupae was as high as 2310 Gy, whereas that for inhibition of F 1 egg hatching was only 66 Gy. ED 99 value for inhibition of hatching of F 1 eggs which were laid by irradiated adults was estimated to 194 Gy. X-ray irradiation against H. armigera is recommended as an alternative method to methyl bromide fumigation for phytosanitary treatments during quarantine. X-ray radiation dose of 200 Gy is proposed as a potential quarantine treatment dose for H. armigera eggs and larvae. - Highlights: • X-ray irradiation induced abnormal development of Helicoverpa armigera. • ED 99 value for inhibition of pupation and adult emergence of irradiated egg was estimated at 210 and 154 Gy, respectively. • ED 99 value for inhibition of pupation and adult emergence of irradiated larva was estimated at 221 and 167 Gy, respectively

  6. Survival and reproductive capacity of the tobacco budworm, heliothis virescens (lepidoptera:noctuidae), irradiated as diapausing and young nondiapausing pupae

    Proshold, F.I.; North, D.T.

    1978-01-01

    Pupal survival, mating, and sperm transfer in tobacco budworm, Heliothis virescens (F.), irradiated as diapause pupae, decreased proportionately with increasing doses of 3, 5, and 7.5 krad. Also, the fertility of tobacco budworms irradiated as nondiapause pupae and of the F 1 progeny of such males decreased with increasing dose. When the female partner received eupyrene sperm, insects irradiated while the pupae were in diapause were fertile as were their progeny. Therefore, it does not appear plausible to irradiate diapause pupae of our strain of tobacco budworms to obtain sterile insects for a release program. (author)

  7. Aromatic/heterocyclic amino acids and the simulated sunlight-ultraviolet inactivation of the Heliothis/Helicoverpa baculovirus

    Ignoffo, C.M.; Garcia, C.

    1995-01-01

    Tryptophan, of five aromatic/heterocyclic amino acids (tyrosine, phenylalanine, proline, histidine) provided significant protection of the Heliothis baculovirus (HzSNPV) from inactivation by simulated ultraviolet (SUV). Fifty percent of SUV protection of HzSNPV with tryptophan or tyrosine was obtained at 0.03 mg/ml and 0.5 mg/ml, respectively. Rates as high as 100.0 mg/ml of phenylalanine, histidine, or proline provided <50% protection. The extent of tryptophan protection was correlated with its absorption in the sunlight UV-B spectra. 16 refs., 2 tabs

  8. Contemporary evolution of a Lepidopteran species, Heliothis virescens, in response to modern agricultural practices.

    Fritz, Megan L; DeYonke, Alexandra M; Papanicolaou, Alexie; Micinski, Stephen; Westbrook, John; Gould, Fred

    2018-01-01

    Adaptation to human-induced environmental change has the potential to profoundly influence the genomic architecture of affected species. This is particularly true in agricultural ecosystems, where anthropogenic selection pressure is strong. Heliothis virescens primarily feeds on cotton in its larval stages, and US populations have been declining since the widespread planting of transgenic cotton, which endogenously expresses proteins derived from Bacillus thuringiensis (Bt). No physiological adaptation to Bt toxin has been found in the field, so adaptation in this altered environment could involve (i) shifts in host plant selection mechanisms to avoid cotton, (ii) changes in detoxification mechanisms required for cotton-feeding vs. feeding on other hosts or (iii) loss of resistance to previously used management practices including insecticides. Here, we begin to address whether such changes occurred in H. virescens populations between 1997 and 2012, as Bt-cotton cultivation spread through the agricultural landscape. For our study, we produced an H. virescens genome assembly and used this in concert with a ddRAD-seq-enabled genome scan to identify loci with significant allele frequency changes over the 15-year period. Genetic changes at a previously described H. virescens insecticide target of selection were detectable in our genome scan and increased our confidence in this methodology. Additional loci were also detected as being under selection, and we quantified the selection strength required to elicit observed allele frequency changes at each locus. Potential contributions of genes near loci under selection to adaptive phenotypes in the H. virescens cotton system are discussed. © 2017 John Wiley & Sons Ltd.

  9. Bacillus thuringiensis delta-endotoxin Cry1Ac domain III enhances activity against Heliothis virescens in some, but not all Cry1-Cry1Ac hybrids

    Karlova, R.B.; Weemen, W.M.J.; Naimov, S.; Ceron, J.; Dukiandjiev, S.; Maagd, de R.A.

    2005-01-01

    We investigated the role of domain III of Bacillus thuringiensis d-endotoxin Cry1Ac in determining toxicity against Heliothis virescens. Hybrid toxins, containing domain III of Cry1Ac with domains I and II of Cry1Ba, Cry1Ca, Cry1Da, Cry1Ea, and Cry1Fb, respectively, were created. In this way Cry1Ca,

  10. Baseline Susceptibility of Helicoverpa armigera (Lepidoptera: Noctuidae) to Indoxacarb, Emamectin Benzoate, and Chlorantraniliprole in Australia.

    Bird, Lisa J

    2015-02-01

    Baseline susceptibility of Helicoverpa armigera (Hübner) to emamectin benzoate, chlorantraniliprole, and indoxacarb was determined in feeding assays on insecticide-incorporated artificial diet in the laboratory. The intraspecific variation of H. armigera was established from field populations collected between September 2012 and March 2013, primarily from commercial farms across eastern Australia. Emamectin benzoate had the highest toxicity with a median lethal concentration (LC50) of 0.01 µg/ml diet (n=20 strains). The LC50 for chlorantraniliprole was 0.03 µg/ml diet (n=21 strains), while indoxacarb had the lowest relative toxicity with an average LC50 of 0.3 µg/ml diet (n=22 strains). Variation in susceptibility amongst field strains was 2.3-fold for emamectin benzoate and 2.9-fold for chlorantraniliprole and indoxacarb. Discriminating concentrations of 0.2, 1, and 12 µg of insecticide per milliliter of diet for emamectin benzoate, chlorantraniliprole, and indoxacarb, respectively, were calculated from toxicological data from field H. armigera strains as a first step in resistance management of these classes of insecticide in Australia. The low intraspecific tolerance, high slope values, and goodness-of-fit to a probit binomial model obtained in this study suggest that a feeding assay using diet incorporated insecticide is an effective laboratory method for measuring the dose-responses of these classes of insecticides in H. armigera. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Life table and consumption capacity of corn earworm, Helicoverpa armigera, fed asparagus, Asparagus officinalis.

    Jha, Ratna Kumar; Tuan, Shu-Jen; Chi, Hsin; Tang, Li-Cheng

    2014-03-01

    The life table and consumption rate of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) reared on asparagus, Asparagus officinalis L. (Asparagales: Asparagaceae) were studied under laboratory conditions to assess their interaction. Development, survival, fecundity, and consumption data were analyzed by the age-stage, twosex life table. This study indicated that asparagus is a natural host of H. armigera. However, the poor nutritional content in asparagus foliage and the poor fitness of H. armigera that fed on asparagus indicated that asparagus is a suboptimal host in comparison to hybrid sweet corn. The uncertainty associated with life table parameters was estimated by using jackknife and bootstrap techniques, and the results were compared for statistical inference. The intrinsic rate of increase (r), finite rate of increase (λ), net reproductive rate (R0), and mean generation time (T) were estimated by the jackknife technique to be 0.0780 day(-1), 1.0811 day(-1), 67.4 offspring, and 54.8 days, respectively, while those estimated by the bootstrap technique were 0.0752 day(-1), 1.0781 day(-1), 68.0 offspring, and 55.3 days, respectively. The net consumption rate of H. armigera, as estimated by the jackknife and bootstrap technique, was 1183.02 and 1132.9 mg per individual, respectively. The frequency distribution of sample means obtained by the jackknife technique failed the normality test, while the bootstrap results fit the normal distribution well. By contrast, the relationship between the mean fecundity and the net reproductive rate, as estimated by the bootstrap technique, was slightly inconsistent with the relationship found by mathematical proof. The application of the jackknife and bootstrap techniques in estimating population parameters requires further examination. This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.

  12. The effects of radiation on the biology and reproduction of Helicoverpa armigera (Lepidoptera: Noctuidae)

    Ramos Ocampo, V.; Leon, J.B. de

    2002-01-01

    The effect of irradiating male Helicoverpa armigera with a substerilizing dose (100 Gy) of gamma radiation on the growth, development and reproduction of subsequent generations was studied in the laboratory. This dose of gamma radiation had no significant detrimental effects on larval and pupal weights or on the duration of the pupal period in the F 1 progeny. However, it lengthened the duration of the larval period by two days. In the F 2 generation, the progeny of the Tf 1 FxTf 1 M cross had significantly lighter pupae. The effects of this substerilizing dose of radiation and of the resulting inherited sterility on the reproduction of Helicoverpa armigera were similar to those described for other species of Lepidoptera. No detrimental effects on P 1 and F 1 female fecundity were recorded. Crosses involving Tf 1 females laid only about one half the number of eggs laid by the controls, however the range in the number of eggs laid by these females fell within the normal range for Helicoverpa armigera. Fertility of crosses involving P 1 males was greatly affected; fertility in these females was only 61% of that exhibited by the controls. This deleterious effect was inherited in the F 1 and F 2 generations and was maximally expressed when F 1 progeny of the NFxTM cross were inbred. Egg hatch was almost completely inhibited in sibling crosses while outcrosses of the F 1 progeny showed a 64-70% reduction in egg hatch when compared to controls. (author)

  13. Helicoverpa armigera (Lepidoptera: Noctuidae) larvae that survive sublethal doses of nucleopolyhedrovirus exhibit high metabolic rates.

    Bouwer, Gustav; Nardini, Luisa; Duncan, Frances D

    2009-04-01

    To determine the effect of sublethal doses of Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus (HearSNPV) on the metabolic rate of H. armigera, the respiration rates of third instar H. armigera larvae inoculated with sublethal doses of HearSNPV were evaluated. Respiration rates, measured as the rate of CO(2) production (VCO(2)), were recorded daily using closed-system respirometry. By 4 days post-inoculation (dpi), the metabolic rates of LD(25) or LD(75) survivors were significantly higher than that of uninoculated controls. When dose data were pooled, the VCO(2) values of larvae that survived inoculation (0.0288mlh(-1)), the uninoculated controls (0.0250mlh(-1)), and the larvae that did not survive inoculation (0.0199mlh(-1)) differed significantly from one another. At 4dpi, the VCO(2) of the uninoculated controls were significantly lower than the VCO(2) of inoculation survivors, but significantly higher than the VCO(2) of inoculation non-survivors. Inoculation survivors may have had high metabolic rates due to a combination of viral replication, organ damage, and an energy-intensive induced cellular immune response. The high 4dpi metabolic rate of inoculation survivors may reflect an effective immune response and may be seen as the metabolic signature of larvae that are in the process of surviving inoculation with HearSNPV.

  14. Acute, sublethal, and combination effects of azadirachtin and Bacillus thuringiensis on the cotton bollworm, Helicoverpa armigera.

    Abedi, Zahra; Saber, Moosa; Vojoudi, Samad; Mahdavi, Vahid; Parsaeyan, Ehsan

    2014-02-26

    The cotton bollworm, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) is a polyphagous and cosmopolitan insect pest that causes damage to various plants. In this study, the lethal and sublethal effects of azadirachtin and Bacillus thuringiensis Berliner sub sp . kurstaki (Bacillales: Bacillaceae) were evaluated on third instar H. armigera under laboratory conditions. The LC50 values of azadirachtin and Bt were 12.95 and 96.8 µg a.i./mL, respectively. A total mortality of 56.7% was caused on third instar larvae when LC20 values of the insecticides were applied in combination with each other. The LT50 values of azadirachtin and Bt were 4.8 and 3.6 days, respectively. The results of the sublethal study showed that the application of LC30 value of azadirachtin and Bt reduced the larval and pupal weight and increased larval and pupal duration of H. armigera. The longevity and fecundity of female adults were affected significantly by the insecticides. Female fecundity was reduced by the treatments, respectively. The lowest adult emergence ratio and pupation ratio were observed in the azadirachtin treatment. The results indicated that both insecticides have high potential for controlling of the pest. This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.

  15. Characterization of three novel SINE families with unusual features in Helicoverpa armigera.

    Jianjun Wang

    Full Text Available Although more than 120 families of short interspersed nuclear elements (SINEs have been isolated from the eukaryotic genomes, little is known about SINEs in insects. Here, we characterize three novel SINEs from the cotton bollworm, Helicoverpa armigera. Two of them, HaSE1 and HaSE2, share similar 5' -structure including a tRNA-related region immediately followed by conserved central domain. The 3' -tail of HaSE1 is significantly similar to that of one LINE retrotransposon element, HaRTE1.1, in H. armigera genome. The 3' -region of HaSE2 showed high identity with one mariner-like element in H. armigera. The third family, termed HaSE3, is a 5S rRNA-derived SINE and shares both body part and 3'-tail with HaSE1, thus may represent the first example of a chimera generated by recombination between 5S rRNA and tRNA-derived SINE in insect species. Further database searches revealed the presence of these SINEs in several other related insect species, but not in the silkworm, Bombyx mori, indicating a relatively narrow distribution of these SINEs in Lepidopterans. Apart from above, we found a copy of HaSE2 in the GenBank EST entry for the cotton aphid, Aphis gossypii, suggesting the occurrence of horizontal transfer.

  16. Characterization of Three Novel SINE Families with Unusual Features in Helicoverpa armigera

    Wang, Jianjun; Wang, Aina; Han, Zhaojun; Zhang, Zan; Li, Fei; Li, Xianchun

    2012-01-01

    Although more than 120 families of short interspersed nuclear elements (SINEs) have been isolated from the eukaryotic genomes, little is known about SINEs in insects. Here, we characterize three novel SINEs from the cotton bollworm, Helicoverpa armigera. Two of them, HaSE1 and HaSE2, share similar 5′ -structure including a tRNA-related region immediately followed by conserved central domain. The 3′ -tail of HaSE1 is significantly similar to that of one LINE retrotransposon element, HaRTE1.1, in H. armigera genome. The 3′ -region of HaSE2 showed high identity with one mariner-like element in H. armigera. The third family, termed HaSE3, is a 5S rRNA-derived SINE and shares both body part and 3′-tail with HaSE1, thus may represent the first example of a chimera generated by recombination between 5S rRNA and tRNA-derived SINE in insect species. Further database searches revealed the presence of these SINEs in several other related insect species, but not in the silkworm, Bombyx mori, indicating a relatively narrow distribution of these SINEs in Lepidopterans. Apart from above, we found a copy of HaSE2 in the GenBank EST entry for the cotton aphid, Aphis gossypii, suggesting the occurrence of horizontal transfer. PMID:22319625

  17. Bacterial Expression and Kinetic Analysis of Carboxylesterase 001D from Helicoverpa armigera

    Yongqiang Li

    2016-04-01

    Full Text Available Carboxylesterasesare an important class of detoxification enzymes involved in insecticide resistance in insects. A subgroup of Helicoverpa armigera esterases, known as Clade 001, was implicated in organophosphate and pyrethroid insecticide resistance due to their overabundance in resistant strains. In this work, a novel carboxylesterasegene 001D of H. armigera from China was cloned, which has an open reading frame of 1665 nucleotides encoding 554 amino acid residues. We used a series of fusion proteins to successfully express carboxylesterase 001D in Escherichia coli. Three different fusion proteins were generated and tested. The enzyme kinetic assay towards 1-naphthyl acetate showed all three purified fusion proteins are active with a Kcat between 0.35 and 2.29 s−1, and a Km between 7.61 and 19.72 μM. The HPLC assay showed all three purified fusion proteins had low but measurable hydrolase activity towards β-cypermethrin and fenvalerate insecticides (specific activities ranging from 0.13 to 0.67 μM·min−1·(μM−1·protein. The enzyme was stable up to 40 °C and at pH 6.0–11.0. The results imply that carboxylesterase 001D is involved in detoxification, and this moderate insecticide hydrolysis may suggest that overexpression of the gene to enhance insecticide sequestration is necessary to allow carboxylesterases to confer resistance to these insecticides in H. armigera.

  18. Targeting chitinase gene of Helicoverpa armigera by host-induced RNA interference confers insect resistance in tobacco and tomato.

    Mamta; Reddy, K R K; Rajam, M V

    2016-02-01

    Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) is a devastating agricultural insect pest with broad spectrum of host range, causing million dollars crop loss annually. Limitations in the present conventional and transgenic approaches have made it crucial to develop sustainable and environmental friendly methods for crop improvement. In the present study, host-induced RNA interference (HI-RNAi) approach was used to develop H. armigera resistant tobacco and tomato plants. Chitinase (HaCHI) gene, critically required for insect molting and metamorphosis was selected as a potential target. Hair-pin RNAi construct was prepared from the conserved off-target free partial HaCHI gene sequence and was used to generate several HaCHI-RNAi tobacco and tomato plants. Northern hybridization confirmed the production of HaCHI gene-specific siRNAs in HaCHI-RNAi tobacco and tomato lines. Continuous feeding on leaves of RNAi lines drastically reduced the target gene transcripts and consequently, affected the overall growth and survival of H. armigera. Various developmental deformities were also manifested in H. armigera larvae after feeding on the leaves of RNAi lines. These results demonstrated the role of chitinase in insect development and potential of HI-RNAi for effective management of H. armigera.

  19. Induced resistance to Helicoverpa armigera through exogenous application of jasmonic acid and salicylic acid in groundnut, Arachis hypogaea.

    War, Abdul Rashid; Paulraj, Michael Gabriel; Ignacimuthu, Savarimuthu; Sharma, Hari Chand

    2015-01-01

    Induced resistance to Helicoverpa armigera through exogenous application of jasmonic acid (JA) and salicylic acid (SA) was studied in groundnut genotypes (ICGV 86699, ICGV 86031, ICG 2271 and ICG 1697) with different levels of resistance to insects and the susceptible check JL 24 under greenhouse conditions. Activities of oxidative enzymes and the amounts of secondary metabolites and proteins were quantified at 6 days after JA and SA application/insect infestation. Data were also recorded on plant damage and H. armigera larval weights and survival. Higher levels of enzymatic activities and amounts of secondary metabolites were observed in the insect-resistant genotypes pretreated with JA and then infested with H. armigera than in JL 24. The insect-resistant genotypes suffered lower insect damage and resulted in poor survival and lower weights of H. armigera larvae than JL 24. In some cases, JA and SA showed similar effects. JA and SA induced the activity of antioxidative enzymes in groundnut plants against H. armigera, and reduced its growth and development. However, induced response to application of JA was greater than to SA, and resulted in reduced plant damage, and larval weights and survival, suggesting that induced resistance can be used as a component of pest management in groundnut. © 2014 Society of Chemical Industry.

  20. Genomic sequencing and analyses of HearMNPV—a new Multinucleocapsid nucleopolyhedrovirus isolated from Helicoverpa armigera

    Tang Ping

    2012-08-01

    Full Text Available Abstract Background HearMNPV, a nucleopolyhedrovirus (NPV, which infects the cotton bollworm, Helicoverpa armigera, comprises multiple rod-shaped nucleocapsids in virion(as detected by electron microscopy. HearMNPV shows a different host range compared with H. armigera single-nucleocapsid NPV (HearSNPV. To better understand HearMNPV, the HearMNPV genome was sequenced and analyzed. Methods The morphology of HearMNPV was observed by electron microscope. The qPCR was used to determine the replication kinetics of HearMNPV infectious for H. armigera in vivo. A random genomic library of HearMNPV was constructed according to the “partial filling-in” method, the sequence and organization of the HearMNPV genome was analyzed and compared with sequence data from other baculoviruses. Results Real time qPCR showed that HearMNPV DNA replication included a decreasing phase, latent phase, exponential phase, and a stationary phase during infection of H. armigera. The HearMNPV genome consists of 154,196 base pairs, with a G + C content of 40.07%. 162 putative ORFs were detected in the HearMNPV genome, which represented 90.16% of the genome. The remaining 9.84% constitute four homologous regions and other non-coding regions. The gene content and gene arrangement in HearMNPV were most similar to those of Mamestra configurata NPV-B (MacoNPV-B, but was different to HearSNPV. Comparison of the genome of HearMNPV and MacoNPV-B suggested that HearMNPV has a deletion of a 5.4-kb fragment containing five ORFs. In addition, HearMNPV orf66, bro genes, and hrs are different to the corresponding parts of the MacoNPV-B genome. Conclusions HearMNPV can replicate in vivo in H. armigera and in vitro, and is a new NPV isolate distinguished from HearSNPV. HearMNPV is most closely related to MacoNPV-B, but has a distinct genomic structure, content, and organization.

  1. Euxesta spp. NEW PEST IN Zea mays L. VAR. rugosa: ASSOCIATION WITH Heliothis zea ATTACKS IN SPRING AND SUMMER SEEDS

    María Cecilia Curis

    2015-12-01

    Full Text Available The "corn silk fly" of maize (Euxesta spp. Loew, 1868 appeared in 2005 in Santa Fe (Argentina, causing damage to the ears. The attacks are related to temperature, crop growth stage and previous attack of other pests. For this new pest, we determined the species present, the damage on Bt sweet corn plantings in two seasons (August and February, the association of attacks with Heliothis zea (Boddie, 1850 and the presence of parasitoids. Larvae counts of H. zea and Euxesta spp. began in the phenological stage of R2 and ended in R5 and consisted of removing at random from each batch (three for each planting season four ears. In laboratory we determined the percentage of damage on the ears and number of larvae of Euxesta spp. and H. zea, discriminated by size. Fly was identified as E. eluta, damage was greatest in the early spring planting corn. Attacks were correlated with H. zea.

  2. Interaction of plant cell signaling molecules, salicylic acid and jasmonic acid, with the mitochondria of Helicoverpa armigera.

    Akbar, S M D; Sharma, H C; Jayalakshmi, S K; Sreeramulu, K

    2012-02-01

    The cotton bollworm, Helicoverpa armigera is a polyphagous pest in Asia, Africa, and the Mediterranean Europe. Salicylic acid (SA) and jasmonic acid (JA) are the cell signaling molecules produced in response to insect attack in plants. The effect of these signaling molecules was investigated on the oxidative phosphorylation and oxidative stress of H. armigera. SA significantly inhibited the state III and state IV respiration, respiratory control index (RCI), respiratory complexes I and II, induced mitochondrial swelling, and cytochrome c release in vitro. Under in vivo conditions, SA induced state IV respiration as well as oxidative stress in time- and dose-dependent manner, and also inhibited the larval growth. In contrast, JA did not affect the mitochondrial respiration and oxidative stress. SA affected the growth and development of H. armigera, in addition to its function as signaling molecules involved in both local defense reactions at feeding sites and the induction of systemic acquired resistance in plants.

  3. Insecticidal activity of venomous saliva from Rhynocoris fuscipes (Reduviidae against Spodoptera litura and Helicoverpa armigera by microinjection and oral administration

    K Sahayaraj

    2011-01-01

    Full Text Available Rhynocoris fuscipes is a potential predator of many economically important pests in India. In the present study, its venomous saliva (VS was collected by milking and diluted with HPLC grade water to different concentrations (200, 400, 600, 800 and 1000 ppm. Microinjection of Rhynocoris fuscipes VS was more toxic than its oral administration in Helicoverpa armigera (cotton bollworm and Spodoptera litura (tobacco cutworm. Thus, R. fuscipes VS was found to be toxic to third instar S. litura and H. armigera with respective LD50s of 846.35 and 861.60 ppm/larva at 96 hours after microinjection. The current results showed that VS of Rhynocoris fuscipes caused mortality of H. armigera and S. litura. Active peptides from VS may be isolated, identified and assessed for their impact in order to ascertain how they alter the physiology of these pests, information that could be applicable in pest management programs.

  4. Activity of Selected Formulated Biorational and Synthetic Insecticides Against Larvae of Helicoverpa armigera (Lepidoptera: Noctuidae).

    Vivan, L M; Torres, J B; Fernandes, P L S

    2017-02-01

    This work studied 17 insecticides belonging to nucleopolyhedrovirus (NPV), Bacillus thuringiensis (Bt kurstaki and Bt aizawai), benzoylureas (insect growth regulators [IGRs]), carbamates, organophosphates, spinosyns, and diamides against larvae of Helicoverpa armigera (Hübner), invasive species in the South American continent. Larvae of different instars were fed for 7 d with untreated or insecticide-treated diets. Mortality was recorded daily for 7 d, and surviving larvae were individually weighed on the seventh day. The NPV and Bt insecticides caused 100% mortality of first-instar larvae and first-instar and second-instar larvae, respectively. However, both NPV and Bt-based products caused low mortality of third-instar larvae and did not kill older larvae. The IGR lufenuron was highly effective against all three ages of larvae tested, whereas teflubenzuron and triflumuron produced maximum 60% mortality of second-instar larvae and lower than 50% to older larvae. Thiodicarb, chlorantraniliprole, indoxacarb, chlorpyrifos, and chlorfenapyr, irrespective of tested age, caused 100% mortality of larvae, with the last two insecticides reaching 100% mortality within 2 d of feeding on the treated diet. Flubendiamide caused lower mortality but significantly affected the weight of surviving larvae, whereas neither spinosad nor methomyl produced significant mortality or affected the weight of larvae. Based on the results, the age of H. armigera larvae plays an important role in the recommendation of NPV and Bt insecticides. Furthermore, there are potential options between biological and synthetic insecticides tested against H. armigera, and recording larval size during monitoring, in addition to the infestation level, should be considered when recommending biological-based insecticides to control this pest. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Effects of gamma irradiation on the sperm transmission and oviposition response in Helicoverpa armigera (L. Noctuidae)

    Liu Xiaohui; Wang Huasong; Song Jiaxiang

    1999-12-01

    The transmission of sperm by unirradiated and irradiated cotton bollworm, Helicoverpa armigera, was studied by live dissection of the female immediately after the initiation of mating. In cotton bollworm the sperm transfer was a rather complex process. In fact, the unirradiated male failed to transfer sperm in about 19% of their matings. After being irradiated with 250 Gy and 400 Gy, the aberrations of sperm transmission were about 21% and 50% respectively. The failure of spermatophore 'cap' location was an important reason of sperm transmission aberrations. When female mated to high-dose-irradiated males, its oviposition response appeared abnormal

  6. Behaviour of wild-type and genetically modified baculoviruses in the Helicoverpa armigera - cotton system: a simulation approach

    Sun, X.

    2005-01-01

    Keywords:   Helicoverpa armigera , baculovirus, genetic modification, cotton,transmission

  7. Modelling biological control with wild-type and genetically modified baculoviruses in the Helicoverpa armigera-cotton system

    Sun, X.; Werf, van der W.; Bianchi, F.J.J.A.; Hu, Z.; Vlak, J.M.

    2006-01-01

    A comprehensive model was developed to simulate virus epizootics in a stage structured insect population and analyse scenarios for the biological control of cotton bollworm (CBW), Helicoverpa armigera, in cotton, using wild-type or genetically modified baculoviruses. In simulations on dosage and

  8. The efficacy of Beauveria bassiana, jasmonic acid and chlorantraniliprole on larval populations of Helicoverpa armigera in chickpea crop ecosystems.

    Younas, Aneela; Wakil, Waqas; Khan, Zaeema; Shaaban, Muhammad; Prager, Sean Michael

    2017-02-01

    A robust integrated pest management (IPM) programme is needed to reduce the use of insecticides in controlling Helicoverpa armigera. Therefore, a 2 year field study was conducted to evaluate the use of alternative control measures (biochemical use) for H. armigera relative to exclusively using chemical insecticides. The entomopathogenic fungus Beauveria bassiana, jasmonic acid and the insecticide chlorantraniliprole were each applied twice during the chickpea growing season. All three applied materials (either alone or combined) significantly (P ≤ 0.05) reduced the larval population of H. armigera and pod infestation. Effects increased with time, and the maximum difference was observed 7 days after the second application in each year. The lowest numbers of larvae per plant and pod infestation were in the B. bassiana 3.21 × 10 6 + chlorantraniliprole treatment in both 2009/2010 and 2010/2011 year. The reduction in the larval population and pod infestation increased chickpea yield and the highest yield in both seasons, and the maximum yield was obtained in the B. bassiana 3.21 × 10 6 + chlorantraniliprole treatment. The populations of natural enemies were highest in the jasmonic acid treatment. The results suggest that B. bassiana, jasmonic acid and chlorantraniliprole may be useful components for the H. armigera IPM strategy. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  9. Experience-based behavioral and chemosensory changes in the generalist insect herbivore Helicoverpa armigera exposed to two deterrent plant chemicals

    Zhou, D.; Loon, van J.J.A.; Wang, C.Z.

    2010-01-01

    Behavioral and electrophysiological responses of larvae of the polyphagous moth species Helicoverpa armigera to two plant-derived allelochemicals were studied, both in larvae that had been reared on a diet devoid of these compounds and in larvae previously exposed to these compounds. In dual-choice

  10. Functional specificity of sex pheromone receptors in the cotton bollworm Helicoverpa armigera.

    Yang Liu

    Full Text Available Male moths can accurately perceive the sex pheromone emitted from conspecific females by their highly accurate and specific olfactory sensory system. Pheromone receptors are of special importance in moth pheromone reception because of their central role in chemosensory signal transduction processes that occur in olfactory receptor neurons in the male antennae. There are a number of pheromone receptor genes have been cloned, however, only a few have been functionally characterized. Here we cloned six full-length pheromone receptor genes from Helicoverpa armigera male antennae. Real-time PCR showing all genes exhibited male-biased expression in adult antennae. Functional analyses of the six pheromone receptor genes were then conducted in the heterologous expression system of Xenopus oocytes. HarmOR13 was found to be a specific receptor for the major sex pheromone component Z11-16:Ald. HarmOR6 was equally tuned to both of Z9-16: Ald and Z9-14: Ald. HarmOR16 was sensitively tuned to Z11-16: OH. HarmOR11, HarmOR14 and HarmOR15 failed to respond to the tested candidate pheromone compounds. Our experiments elucidated the functions of some pheromone receptor genes of H. armigera. These advances may provide remarkable evidence for intraspecific mating choice and speciation extension in moths at molecular level.

  11. Alterations in the Helicoverpa armigera midgut digestive physiology after ingestion of pigeon pea inducible leucine aminopeptidase.

    Purushottam R Lomate

    Full Text Available Jasmonate inducible plant leucine aminopeptidase (LAP is proposed to serve as direct defense in the insect midgut. However, exact functions of inducible plant LAPs in the insect midgut remain to be estimated. In the present investigation, we report the direct defensive role of pigeon pea inducible LAP in the midgut of Helicoverpa armigera (Lepidoptera: Noctuidae and responses of midgut soluble aminopeptidases and serine proteinases upon LAP ingestion. Larval growth and survival was significantly reduced on the diets supplemented with pigeon pea LAP. Aminopeptidase activities in larvae remain unaltered in presence or absence of inducible LAP in the diet. On the contrary, serine proteinase activities were significantly decreased in the larvae reared on pigeon pea LAP containing diet as compared to larvae fed on diet without LAP. Our data suggest that pigeon pea inducible LAP is responsible for the degradation of midgut serine proteinases upon ingestion. Reduction in the aminopeptidase activity with LpNA in the H. armigera larvae was compensated with an induction of aminopeptidase activity with ApNA. Our findings could be helpful to further dissect the roles of plant inducible LAPs in the direct plant defense against herbivory.

  12. Investigation on mating habit and sexual competition ability of Helicoverpa armigera sterilized by irradiation

    Xia Darong; Yang Rongxin; Gu Weiping; Zhang Yanjun

    1999-01-01

    Mating habit and sexual competition ability of Helicoverpa armigera irradiated with 300 Gy of γ-rays were observed. The results showed that when reared in laboratory, most adults mated at 4-7 o'clock, a small proportion of adults mated at 2-3 o'clock or at 8-9 o'clock in the morning, meanwhile wild population mated two and a half hours earlier than laboratory populations did. No difference in mating habit and sexual competition ability was found between the irradiation-sterilized and normal adults except that the effective mating rate of the former was 61.6%, one third less than that of the latter ones. Most irradiation-sterilized adults mated one time in their whole lives, only a few could mate 2-3 times and even 5 times, indicating that the multi-mating characteristic of Helicoverpa armigera was not changed by irradiation. It can be concluded that irradiated sterile insect technique is feasible for integrated controlling the cotton bollworm

  13. The expression of proteins involved in digestion and detoxification are regulated in Helicoverpa armigera to cope up with chlorpyrifos insecticide.

    Dawkar, Vishal V; Chikate, Yojana R; More, Tushar H; Gupta, Vidya S; Giri, Ashok P

    2016-02-01

    Helicoverpa armigera is a key pest in many vital crops, which is mainly controlled by chemical strategies. To manage this pest is becoming challenging due to its ability and evolution of resistance against insecticides. Further, its subsequent spread on nonhost plant is remarkable in recent times. Hence, decoding resistance mechanism against phytochemicals and synthetic insecticides is a major challenge. The present work describes that the digestion, defense and immunity related enzymes are associated with chlorpyrifos resistance in H. armigera. Proteomic analysis of H. armigera gut tissue upon feeding on chlorpyrifos containing diet (CH) and artificial diet (AD) using nano-liquid chromatography-mass spectrometry identified upregulated 23-proteins in CH fed larvae. Database searches combined with gene ontology analysis revealed that the identified gut proteins engrossed in digestion, proteins crucial for immunity, adaptive responses to stress, and detoxification. Biochemical and quantitative real-time polymerase chain reaction analysis of candidate proteins indicated that insects were struggling to get nutrients and energy in presence of CH, while at the same time endeavoring to metabolize chlorpyrifos. Moreover, we proposed a potential processing pathway of chlorpyrifos in H. armigera gut by examining the metabolites using gas chromatography-mass spectrometry. H. armigera exhibit a range of intriguing behavioral, morphological adaptations and resistance to insecticides by regulating expression of proteins involved in digestion and detoxification mechanisms to cope up with chlorpyrifos. In these contexts, as gut is a rich repository of biological information; profound analysis of gut tissues can give clues of detoxification and resistance mechanism in insects. © 2014 Institute of Zoology, Chinese Academy of Sciences.

  14. Inheritance of electrophysiological responses to leaf saps of host- and nonhost plants in two helicoverpa species and their hybrids

    Tang, Q.B.; Huang, L.Q.; Wang, C.Z.; Tang, Q.B.T.; Zhan, H.; Loon, van J.J.A.

    2014-01-01

    The polyphagous cotton bollworm Helicoverpa armigera (Hubner) and the oligophagous oriental tobacco budworm Helicoverpa assulta (Guenee) (Lepidoptera: Noctuidae) display contrasting heritable feeding preferences for cotton and pepper leaves. In this study, electrophysiological response patterns to

  15. Functional response of Chrysoperla carnea (Neuroptera: Chrysopidae) to Helicoverpa armigera (Lepidoptera: Noctuidae): effect of prey and predator stages

    Hassanpour, Mehdi; Mohaghegh, Jafar; Iranipour, Shahzad

    2011-01-01

    Understanding predator–prey interactions has a pivotal role in biological control programs. This study evaluated the functional response of three larval instars of the green lacewing, Chrysoperla carnea (Stephens), preying upon eggs and first instar larvae of the cotton bollworm, Helicoverpa...... armigera Hübner. The first and second instar larvae of C. carnea exhibited type II functional responses against both prey stages. However, the third instar larvae of C. carnea showed a type II functional response to the first instar larvae of H. armigera, but a type III functional response to the eggs....... For the first instar larvae of C. carnea, the attack rate on H. armigera eggs was significantly higher than that on the larvae, whereas the attack rate of the second instar C. carnea on H. armigera larvae was significantly higher than that on the eggs. For the third instar larvae of C. carnea, the attack rate...

  16. Tarsal taste neuron activity and proboscis extension reflex in response to sugars and amino acids in Helicoverpa armigera (Hübner)

    Zhang, Y.F.; Loon, van J.J.A.; Wang, C.Z.

    2010-01-01

    In adult female Helicoverpa armigera (Hübner), the fifth tarsomere of the prothoracic legs bears 14 gustatory trichoid chemosensilla. These chemosensilla were characterized through electrophysiological experiments by stimulating with sucrose, glucose, fructose, maltose, myo-inositol and 20 common

  17. Sub-lethal effects of Vip3A toxin on survival, development and fecundity of Heliothis virescens and Plutella xylostella.

    Gulzar, Asim; Wright, Denis J

    2015-11-01

    The assessment of sub-lethal effects is important to interpret the overall insecticide efficacy in controlling insect pest populations. In addition to the lethal effect, sub-lethal effects may also occur in exposed insects. Vegetative insecticidal proteins (Vips) have shown a broad spectrum of insecticidal activity against many insect pest species. In this study the sub-lethal effects of the Bacillus thuringiensis vegetative insecticidal toxin Vip3A on the development and reproduction of Heliothis virescens F. and Plutella xylostella L. were evaluated in the laboratory. The results indicated that the sub-lethal concentration of Vip3A increased the duration of the larval and pupal stages as compared with the control treatment for both species. The percent pupation and percent adult emergence were significantly lower for Vip3A-treated insects. The proportion of pairs that produced eggs and the longevity of adults were not significantly different between treatments. H. virescens and P. xylostella treated with Vip3A showed an 11 and 17 % decrease in their intrinsic rate of increase (rm) respectively compared with untreated insects. The results from this study will be helpful to develop the strategy to incorporate Vip 3A containing crops in an integrated pest management programme.

  18. Activity in neurons of a putative protocerebral circuit representing information about a ten component plant odour blend in Heliothis virescens.

    Bjarte Bye Løfaldli

    2012-09-01

    Full Text Available The olfactory pathway in the insect brain is anatomically well described from the antennal lobe to the mushroom bodies and the lateral protocerebrum in several species. Less is known about the further connections of the olfactory network in protocerebrum and how information about relevant plant odorants and mixtures are represented in this network, resulting in output information mediated by descending neurons. In the present study we have recorded intracellularly followed by dye injections from neurons in the lateral- and superior protocerebrum of the moth, Heliothis virescens. As relevant stimuli, we have used selected primary plant odorants and mixtures of them. The results provide the morphology and physiological responses of neurons involved in a putative circuit connecting the mushroom body lobes, the superior and the lateral protocerebrum, as well as input to superior and lateral protocerebrum by one multiglomerular antennal lobe neuron and output from the lateral protocerebrum by one descending neuron. All neurons responded to one particular mixture of ten primary plant odorants, some of them also to single odorants of the mixture. Altogether, the physiological data indicate integration in protocerebral neurons of information from several of the receptor neuron types functionally described in this species.

  19. Survival and development of Heliothis virescens (Lepidoptera: Noctuidae) larvae on isogenic tobacco lines with different levels of alkaloids.

    Jackson, D Michael; Johnson, A W; Stephenson, M G

    2002-12-01

    Levels of pyridine alkaloids were measured in 18 tobacco, Nicotiana tabacum L., entries from three parental isolines ('NC 95', 'SC 58', and 'Coker 139'), grown at Tifton, GA, Florence, SC, and Oxford, NC, in 1991. Levels of alkaloids in bud leaves (first fully unfolded leaf below the apical leaf bud) were negatively correlated to natural infestation ratings of tobacco budworm larvae, Heliothis virescens (F.), 7 wk after transplanting. For artificially infested bud leaves at Oxford, there was a significant negative correlation between levels of total alkaloids and larval weights after 1 wk of feeding. In 1992, four entries from the 'NC 95' isoline were grown at Oxford, and samples for alkaloid analyses were taken every 2 wk at several leaf positions on each plant. During weeks 4, 8, 12, and 16, second instar tobacco budworms were caged on individual, intact leaves inside perforated plastic bags in the field. The survival and development of tobacco budworm larvae after 1 wk were negatively correlated with levels of alkaloids at the various leaf positions. Larvae survived better and grew faster on the bud leaves of each entry where alkaloid levels were lower than they did on leaves further down the stalk where alkaloid levels were higher. More larvae survived on the lower leaves of the low alkaloid lines than on the lower leaves of the high alkaloid lines. Even moderate increases in pyridine alkaloids had negative effects on tobacco budworm survival and development. Nicotine constituted >97% of the pyridine alkaloids in the 'NC95' isoline each year.

  20. Lethal and sublethal effects of cantharidin on the life history traits and population parameters of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae).

    Khan, Rashid A; Rashid, Maryam; Wang, Dun; Zhang, Ya-Lin

    2014-01-01

    The cotton bollworm, Helicoverpa armigera (Hübner), is a serious and cosmopolitan pest of many economic crops. Its control has not been adequate owing to its resistance to many groups of insecticides. Toxicity of cantharidin on armyworm and diamondback moth has already been reported. However, its toxicity on H. armigera has not been investigated previously. In this study, lethal and sublethal effects of cantharidin on H. armigera under laboratory conditions are reported. Results showed gross abnormalities in the population parameters of H. armigera, ranging from larvae to adults. Reduction in larval weight and wing malformation were observed in the cantharidin-treated population cohort, and higher mortality at the larval, pupal and adult stages was observed in cantharidin-treated H. armigera compared with the control. Moreover, almost 5 times less fecundity was recorded in the treated population cohort. Fertility was also severely affected, and reduction in all population parameters was observed. Cantharidin caused larval mortality and other serious abnormalities in H. armigera population parameters, and therefore may have positive implications for pest management decision-making process. More interestingly, the experiment revealed that cantharidin in sublethal dose mimicked insect growth regulator insecticides. Furthermore, cantharidin could be used as a precursor compound for the synthesis of new analogues and compounds to replace ineffective older compounds. © 2013 Society of Chemical Industry.

  1. Comparative analysis of the protein compositions between wild type and body color mutant of helicoverpa armigera adult

    He Lihua; Chen Jin'e; Liu Yan; Wang Yongqiang; Liu Peigang; Meng Zhiqi

    2012-01-01

    To gain an in-depth understanding of the fineness and regulation mechanism of body color mutant of Helicoverpa armigera Hbner, the protein composition differences between adult of dominant mutant, recessive mutant and wild type were studied using the SDS-PAGE combined with MALDI-TOF-TOF/MS and bioinformatics analysis. The results indicated that the protein composition of the dominant mutant and wild type had little difference. However, there were obvious differences between the recessive mutant and wild-type. Three specific stripe were chosen for mass spectrometry and bioinformatics analysis, and two types of proteins related to energy metabolism and cytoskeleton were identified. These findings suggested that the two types of proteins may be associated with occurrence and regulation of body color mutant traits of H. armigera. (authors)

  2. Field evolved resistance in Helicoverpa armigera (Lepidoptera: Noctuidae to Bacillus thuringiensis toxin Cry1Ac in Pakistan.

    Anwaar H K Alvi

    Full Text Available Helicoverpa armigera (Hübner is one of the most destructive pests of several field and vegetable crops, with indiscriminate use of insecticides contributing to multiple instances of resistance. In the present study we assessed whether H. armigera had developed resistance to Bt cotton and compared the results with several conventional insecticides. Furthermore, the genetics of resistance was also investigated to determine the inheritance to Cry1Ac resistance. To investigate the development of resistance to Bt cotton, and selected foliar insecticides, H. armigera populations were sampled in 2010 and 2011 in several cotton production regions in Pakistan. The resistance ratios (RR for Cry1Ac, chlorpyrifos, profenofos, cypermethrin, spinosad, indoxacarb, abamectin and deltamethrin were 580-fold, 320-, 1110-, 1950-, 200-, 380, 690, and 40-fold, respectively, compared with the laboratory susceptible (Lab-PK population. Selection of the field collected population with Cry1Ac in 2010 for five generations increased RR to 5440-fold. The selection also increased RR for deltamethrin, chlorpyrifos, profenofos, cypermethrin, spinosad, indoxacarb, abamectin to 125-folds, 650-, 2840-, 9830-, 370-, 3090-, 1330-fold. The estimated LC(50s for reciprocal crosses were 105 µg/ml (Cry1Ac-SEL female × Lab-PK male and 81 g µg/ml (Lab-PK female × Cry1Ac-SEL male suggesting that the resistance to Cry1Ac was autosomal; the degree of dominance (D(LC was 0.60 and 0.57 respectively. Mixing of enzyme inhibitors significantly decreased resistance to Cry1Ac suggesting that the resistance to Cry1Ac and other insecticides tested in the present study was primarily metabolic. Resistance to Cry1Ac was probably due to a single but unstable factor suggesting that crop rotation with non-Bt cotton or other crops could reduce the selection pressure for H. armigera and improve the sustainability of Bt cotton.

  3. Hybridization between Helicoverpa armigera and Helicoverpa assulta (Lepidoptera: Noctuidae): development and morphological characterization of F1 hybrids

    Zhao, X. C.; Dong, J. F.; Tang, Q. B.; Yan, Y. H.; Gelbič, Ivan; Van Loon, J. J. A.; Wang, C. Z.

    2005-01-01

    Roč. 95, č. 5 (2005), s. 409-416 ISSN 0007-4853 Grant - others:Chinese Academy of Sciences(CN) KSCX2-SW-105; Major State Basic Research Project of China(CN) 2000016208; National Natural Science Foundation of China(CN) 30330100 Institutional research plan: CEZ:AV0Z50070508 Keywords : Helicoverpa armigera * Helicoverpa assulta * Noctuidae Subject RIV: ED - Physiology Impact factor: 1.333, year: 2005

  4. Cantharidin Impedes Activity of Glutathione S-Transferase in the Midgut of Helicoverpa armigera Hübner

    Ya Lin Zhang

    2013-03-01

    Full Text Available Previous investigations have implicated glutathione S-transferases (GSTs as one of the major reasons for insecticide resistance. Therefore, effectiveness of new candidate compounds depends on their ability to inhibit GSTs to prevent metabolic detoxification by insects. Cantharidin, a terpenoid compound of insect origin, has been developed as a bio-pesticide in China, and proves highly toxic to a wide range of insects, especially lepidopteran. In the present study, we test cantharidin as a model compound for its toxicity, effects on the mRNA transcription of a model Helicoverpa armigera glutathione S-transferase gene (HaGST and also for its putative inhibitory effect on the catalytic activity of GSTs, both in vivo and in vitro in Helicoverpa armigera, employing molecular and biochemical methods. Bioassay results showed that cantharidin was highly toxic to H. armigera. Real-time qPCR showed down-regulation of the HaGST at the mRNA transcript ranging from 2.5 to 12.5 folds while biochemical assays showed in vivo inhibition of GSTs in midgut and in vitro inhibition of rHaGST. Binding of cantharidin to HaGST was rationalized by homology and molecular docking simulations using a model GST (1PN9 as a template structure. Molecular docking simulations also confirmed accurate docking of the cantharidin molecule to the active site of HaGST impeding its catalytic activity.

  5. PROTECTION OF SWEET CORN FROM OSTRINIA NUBILALIS HBN. AND HELICOVERPA ARMIGERA HBN.

    Vuković, S; Indić, D; Grahovac, M; Franeta, F

    2015-01-01

    O. nubilalis and H. armigera regularly occur and cause significant damages in corn crops in Serbia, particularly under global warming conditions. Several measures are applied against these pests (crop rotation, tolerant and resistant hybrids, monitoring, forecast, chemical measures). Larvae damage stem, panicle and ear, which favour development of saprophytes and secondary infections by mycotoxin producing, pathogenic fungi. The aim of the paper was to test the efficacy of the insecticides azadirachtin and indoxacarb in sweet corn protection against the mentioned pests. The trials were conducted in 2014 at two localities (Becej B. and PoIjanice P.) on sweet corn, hybrid Enterprise according to standard OEPP methods (PP1/13; 1/152; 1/135). Products on the basis of azadirachtin (10 g a.i./I of product) at a rate of 0.4 and 0.5% and indoxacarb (150 g a.i./I of product) at a rate of 0.25 I/ha, were applied. Treatments were conducted on the 5th of August with tractor sprayers (high clearance). The plot size was 5000 m². Three assessments were made. The first one prior to treatment, on 25 randomly selected plants per replicate, and the number of O. nubilalis and H. armigera egg masses and larvae on silk was registered. In the second assessment (18th of August), on 20 randomly selected plants per replicate, the number of damaged plants and the number of vital larvae was registered. In the third assessment, immediately before harvest (28th of August, i.e. 12th of September) on 20 randomly selected plants per replicate, the number of plants broken below ear (fallen on the ground), damaged ears and vital larvae, was determined. Results are presented as means, efficacy (E%) according to Abbott and significance of differences by LSD test (5%). At B locality egg masses of O. nubilalis were registered on ear silk on 13-19% of plants and larvae on 3-7%, and larvae of H. armigera on 2-4%. At P locality egg masses of O. nubilalis were present on 34-40.8% of plants. After 13 days

  6. Studies on the dispersal, potential and natural population density of the Heliothis comple over some areas of Northeastern Mexico. Part of a coordinated programme on the ecology and behaviour of the Heliothis comple as related to the sterile-male technique

    Tejada, L.O.

    1976-02-01

    Spirulina algae and opaque-2 maize proved very promising sources of protein in the mass rearing of Heliothis under laboratory conditions. They can be developed as a very simple inexpensive larval diet. Opaque-2 is particularly rich in lysine and tryptophan whereas algae are, in addition rich in alanine, tyrosine, other amino acids and in vitamin-B. Their cost is about 70% below that of other sources of protein tested. Larval and pupae weights were higher, though not significantly so, when reared on diets containing spirulina and opaque-2. The life cycle and reproduction of moths from controls and from larvae reared on spirulina and opaque-2 diets proved comparable

  7. Effects of ultraviolet light irradiation on several isozymes in Helicoverpa armigera adults

    Meng Jianyu; Zhang Changyu; Lei Chaoliang

    2012-01-01

    The effects of ultraviolet (UV)light stress on esterase, peroxidases (POX ), and catalase (CAT) isozymes in Helicoverpa armigera (Hiiber) adults were studied by isozyme eleetrophoresis. When exposed to UV light irradiation, zymogram of esterase isozyme changed mainly in number and activity of isozyme. After 30 min and 60 min exposure, the intensity of isozyme bands E4, E9 and El0 were enhanced, E2 and E8 were weakened. The bands E1, E5, E7 and Ell disappeared after UV light irradiation, while E3 and E6 newly emerged. At the longest exposure time (90 min), the intensity of isozyme bands E4 and E9 was enhanced, while the intensity of E2 and E8 was weakened. The bands E1, E5 and E7 disappeared after UV light irradiation, whereas E3 and E6 newly emerged. The intensity of POX band P5 was enhanced in adults following the exposure to UV light for 30, 60, 90 minutes. The intensity of CAT band C1 was enhanced in adults following the exposure to UV light for 30, 60, 90 minutes, but that of band C2 was weakened after 30 min and 90 min exposure in comparison with the control

  8. Characterization of protein phosphatase 5 from three lepidopteran insects: Helicoverpa armigera, Mythimna separata and Plutella xylostella.

    Xi'en Chen

    Full Text Available Protein phosphatase 5 (PP5, a unique member of serine/threonine phosphatases, regulates a variety of biological processes. We obtained full-length PP5 cDNAs from three lepidopteran insects, Helicoverpa armigera, Mythimna separata and Plutella xylostella, encoding predicted proteins of 490 (55.98 kDa, 490 (55.82 kDa and 491 (56.07 kDa amino acids, respectively. These sequences shared a high identity with other insect PP5s and contained the TPR (tetratricopeptide repeat domains at N-terminal regions and highly conserved C-terminal catalytic domains. Tissue- and stage-specific expression pattern analyses revealed these three PP5 genes were constitutively expressed in all stages and in tested tissues with predominant transcription occurring at the egg and adult stages. Activities of Escherichia coli-produced recombinant PP5 proteins could be enhanced by almost 2-fold by a known PP5 activator: arachidonic acid. Kinetic parameters of three recombinant proteins against substrate pNPP were similar both in the absence or presence of arachidonic acid. Protein phosphatases inhibitors, okadaic acid, cantharidin, and endothall strongly impeded the activities of the three recombinant PP5 proteins, as well as exerted an inhibitory effect on crude protein phosphatases extractions from these three insects. In summary, lepidopteran PP5s share similar characteristics and are all sensitive to the protein phosphatases inhibitors. Our results also imply protein phosphatase inhibitors might be used in the management of lepidopteran pests.

  9. Mitochondrial DNA and trade data support multiple origins of Helicoverpa armigera (Lepidoptera, Noctuidae) in Brazil

    Tay, Wee Tek; Walsh, Thomas K.; Downes, Sharon; Anderson, Craig; Jermiin, Lars S.; Wong, Thomas K. F.; Piper, Melissa C.; Chang, Ester Silva; Macedo, Isabella Barony; Czepak, Cecilia; Behere, Gajanan T.; Silvie, Pierre; Soria, Miguel F.; Frayssinet, Marie; Gordon, Karl H. J.

    2017-03-01

    The Old World bollworm Helicoverpa armigera is now established in Brazil but efforts to identify incursion origin(s) and pathway(s) have met with limited success due to the patchiness of available data. Using international agricultural/horticultural commodity trade data and mitochondrial DNA (mtDNA) cytochrome oxidase I (COI) and cytochrome b (Cyt b) gene markers, we inferred the origins and incursion pathways into Brazil. We detected 20 mtDNA haplotypes from six Brazilian states, eight of which were new to our 97 global COI-Cyt b haplotype database. Direct sequence matches indicated five Brazilian haplotypes had Asian, African, and European origins. We identified 45 parsimoniously informative sites and multiple substitutions per site within the concatenated (945 bp) nucleotide dataset, implying that probabilistic phylogenetic analysis methods are needed. High diversity and signatures of uniquely shared haplotypes with diverse localities combined with the trade data suggested multiple incursions and introduction origins in Brazil. Increasing agricultural/horticultural trade activities between the Old and New Worlds represents a significant biosecurity risk factor. Identifying pest origins will enable resistance profiling that reflects countries of origin to be included when developing a resistance management strategy, while identifying incursion pathways will improve biosecurity protocols and risk analysis at biosecurity hotspots including national ports.

  10. Gamma radiation for all phases of life cycle of cotton bollworm Helicoverpa armigera aiming at its control

    Haddad, Gianni Q.; Arthur, Valter, E-mail: ghaddad2001@yahoo.com.br, E-mail: arthur@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil). Laboratório de Radiobiologia e Ambiente; Machi, André R., E-mail: rica_machi@hotmail.com [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    Since the 1950s, scientists have used ionizing radiation to sterilize insects, which are released in nature to mate, but without any progeny. Known as the sterile insect technique (SIT), this insect control method traditionally uses ionizing radiations to sterilize insects, being a technique that does not generate residue, and can act in synergy with the other techniques within integrated pest management. For several years, Brazil has been fighting against the increase of pests, introducing new tactics and techniques within IPM programs, to overcome the resistance of chemical products, such as: reducing residues of pesticides. For some important crops of our country, we have a wide spectrum of pests occurring from beginning to end of the harvest, one of them is the cotton crop and among the key pests of this crop, we have some extremely important caterpillars among them Helicoverpa armigera. Due to this the objective this study was establishes doses of gamma radiation to sterilizing of the phases of : eggs, larvae, pupae and adults of H. armigera aiming their control. The experiment was carried out with application of gamma radiation from a Cobalt-60 source. The treatments consisted of doses of gamma radiation varying of according with the insect phase, being this variation of: 0 (control) to 400 Gy. The experiments with pupae and adult phases showed satisfactory results in the sterilization of H. armigera for use in autocide control programs. The sterilize dose to adult and pupae phase were 400 Gy and 100 Gy respectively, being the best doses for the application of the sterile insect technique to this pest in cotton. (author)

  11. Role of induced glutathione-S-transferase from Helicoverpa armigera (Lepidoptera: Noctuidae) HaGST-8 in detoxification of pesticides.

    Labade, Chaitali P; Jadhav, Abhilash R; Ahire, Mehul; Zinjarde, Smita S; Tamhane, Vaijayanti A

    2018-01-01

    The present study deals with glutathione-S-transferase (GST) based detoxification of pesticides in Helicoverpa armigera and its potential application in eliminating pesticides from the environment. Dietary exposure of a pesticide mixture (organophosphates - chlorpyrifos and dichlorvos, pyrethroid - cypermethrin; 2-15ppm each) to H. armigera larvae resulted in a dose dependant up-regulation of GST activity and gene expression. A variant GST from H. armigera (HaGST-8) was isolated from larvae fed with 10ppm pesticide mixture and it was recombinantly expressed in yeast (Pichia pastoris HaGST-8). HaGST-8 had a molecular mass of 29kDa and was most active at pH 9 at 30°C. GC-MS and LC-HRMS analysis validated that HaGST-8 was effective in eliminating organophosphate type of pesticides and partially reduced the cypermethrin content (53%) from aqueous solutions. Unlike the untransformed yeast, P. pastoris HaGST-8 grew efficiently in media supplemented with pesticide mixtures (200 and 400ppm each pesticide) signifying the detoxification ability of HaGST-8. The amino acid sequence of HaGST-8 and the already reported sequence of HaGST-7 had just 2 mismatches. The studies on molecular interaction strengths revealed that HaGST-8 had stronger binding affinities with organophosphate, pyrethroid, organochloride, carbamate and neonicotinoid type of pesticides. The abilities of recombinant HaGST-8 to eliminate pesticides and P. pastoris HaGST-8 to grow profusely in the presence of high level of pesticide content can be applied for removal of such residues from food, water resources and bioremediation. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Gamma radiation for all phases of life cycle of cotton bollworm Helicoverpa armigera aiming at its control

    Haddad, Gianni Q.; Arthur, Valter

    2017-01-01

    Since the 1950s, scientists have used ionizing radiation to sterilize insects, which are released in nature to mate, but without any progeny. Known as the sterile insect technique (SIT), this insect control method traditionally uses ionizing radiations to sterilize insects, being a technique that does not generate residue, and can act in synergy with the other techniques within integrated pest management. For several years, Brazil has been fighting against the increase of pests, introducing new tactics and techniques within IPM programs, to overcome the resistance of chemical products, such as: reducing residues of pesticides. For some important crops of our country, we have a wide spectrum of pests occurring from beginning to end of the harvest, one of them is the cotton crop and among the key pests of this crop, we have some extremely important caterpillars among them Helicoverpa armigera. Due to this the objective this study was establishes doses of gamma radiation to sterilizing of the phases of : eggs, larvae, pupae and adults of H. armigera aiming their control. The experiment was carried out with application of gamma radiation from a Cobalt-60 source. The treatments consisted of doses of gamma radiation varying of according with the insect phase, being this variation of: 0 (control) to 400 Gy. The experiments with pupae and adult phases showed satisfactory results in the sterilization of H. armigera for use in autocide control programs. The sterilize dose to adult and pupae phase were 400 Gy and 100 Gy respectively, being the best doses for the application of the sterile insect technique to this pest in cotton. (author)

  13. Trans-generational desensitization and within-generational resensitization of a sucrose-best neuron in the polyphagous herbivore Helicoverpa armigera (Lepidoptera: Noctuidae)

    Ma, Ying; Li, Jingjing; Tang, Qingbo; Zhang, Xuening; Zhao, Xincheng; Yan, Fengming; Loon, van Joop J.A.

    2016-01-01

    Dietary exposure of insects to a feeding deterrent substance for hours to days can induce habituation and concomitant desensitization of the response of peripheral gustatory neurons to such a substance. In the present study, larvae of the herbivore Helicoverpa armigera were fed on diets

  14. Formulation of A Novel Phytopesticide PONNEEM and its Potentiality to control generalist Herbivorous Lepidopteran insect pests, Spodoptera litura (Fabricius and Helicoverpa armigera (H übner (Lepidoptera: Noctuidae

    Susaimanickam Maria Packiam

    2012-10-01

    Full Text Available Objective: To evaluate the deterrence of oviposition potentiality of a novel phytopesticide PONNEEM against the generalist herbivorous lepidopteran insect pests Helicoverpa armigera and Spodoptera litura. Methods: Different phytopesticidal formulations were prepared at different ratio to evaluate the deterrence of oviposition activity against S. litura and H. armigera at 5, 10, 15, and 20毺 L/L concentrations. Results: The newly formulated different phytopesticides exhibited good results of oviposition deterrent activity against these two polyphagous insect pests. At 20毺 L/L concentration of PONNEEM, 77.48% of the maximum deterrence of oviposition activity was recorded, followed by formulation A (49.23%. And 68.12% was observed against H. armigera followed by A (49.52%. PONNEEM exhibited statistically significant oviposition deterrent activity compared to all other treatments. Conclusions: The newly formulated PONNEEM was found to be effective phytopesticidal formulation to control the adult of S. litura and H. armigera due to the synergistic effect of biomolecules such as azadirachtin and karanjin. This is the first report of PONNEEM which was patented under the government of India. The potential use of this novel phytopesticide could be an agent of controlling the adults of lepidopteran insect pests which can be applied in the integrated pest management programme.

  15. Genetic engineering of cotton with a novel cry2AX1 gene to impart insect resistance against Helicoverpa armigera

    Karunamurthy Dhivya

    2016-09-01

    Full Text Available Embryogenic calli of cotton (Coker310 were cocultivated with the Agrobacterium tumefaciens strain LBA4404 harbouring the codon-optimised, chimeric cry2AX1 gene consisting of sequences from cry2Aa and cry2Ac genes isolated from Indian strains of Bacillus thuringiensis. Forty-eight putative transgenic plants were regenerated, and PCR analysis of these plants revealed the presence of the cry2AX1 gene in 40 plants. Southern blot hybridisation analysis of selected transgenic plants confirmed stable T-DNA integration in the genome of transformed plants. The level of Cry2AX1 protein expression in PCR positive plants ranged from 4.9 to 187.5 ng g-1 of fresh tissue. A transgenic cotton event, TP31, expressing the cry2AX1 gene showed insecticidal activity of 56.66 per cent mortality against Helicoverpa armigera in detached leaf disc bioassay. These results indicate that the chimeric cry2AX1 gene expressed in transgenic cotton has insecticidal activity against H. armigera.

  16. A toxin-binding alkaline phosphatase fragment synergizes Bt toxin Cry1Ac against susceptible and resistant Helicoverpa armigera.

    Wenbo Chen

    Full Text Available Evolution of resistance by insects threatens the continued success of pest control using insecticidal crystal (Cry proteins from the bacterium Bacillus thuringiensis (Bt in sprays and transgenic plants. In this study, laboratory selection with Cry1Ac yielded five strains of cotton bollworm, Helicoverpa armigera, with resistance ratios at the median lethal concentration (LC50 of activated Cry1Ac ranging from 22 to 1700. Reduced activity and reduced transcription of an alkaline phosphatase protein that binds Cry1Ac was associated with resistance to Cry1Ac in the four most resistant strains. A Cry1Ac-binding fragment of alkaline phosphatase from H. armigera (HaALP1f was not toxic by itself, but it increased mortality caused by Cry1Ac in a susceptible strain and in all five resistant strains. Although synergism of Bt toxins against susceptible insects by toxin-binding fragments of cadherin and aminopeptidase N has been reported previously, the results here provide the first evidence of synergism of a Bt toxin by a toxin-binding fragment of alkaline phosphatase. The results here also provide the first evidence of synergism of a Bt toxin by any toxin-binding peptide against resistant insects.

  17. ATIVIDADE DE DETERRÊNCIA ALIMENTAR DO ÓLEO ESSENCIAL DE LARANJA AMARGA SOBRE Helicoverpa armigera HÜBNER

    Victor Luiz de Souza Lima

    2017-01-01

    Full Text Available Diversas plantas possuem compostos secundários com propriedades inseticidas e o óleo essencial de laranja amarga mostra-se com grande potencial para o controle de pragas. Recentemente, foi registrada no Brasil a espécie Helicoverpa armigera, uma das maiores pragas da agricultura mundial. Tendo em vista a falta de métodos alternativos aos inseticidas para o controle dessa praga, o objetivo desse trabalho foi avaliar os efeitos do óleo essencial de laranja amarga sobre H. armigera. Foi realizado um teste de escolha para avaliar a atividade deterrente. Folhas de tomate foram imersas em soluções contendo óleo de laranja amarga em três concentrações (1, 10 e 100 mg L-1. As folhas tratadas com óleo e folhas não tratadas foram oferecidas à lagartas de segunda instar e após 24h foi calculado o índice de deterrência alimentar (IDA. A concentração de 1 mg L-1 apresentou 71% de deterrência alimentar. Porém as concentrações de 10 e 100 mg L-1 causaram fitotoxidez às folhas de tomate, inviabilizando o consumo pelas lagartas e a estimativa do IDA. Novos testes devem ser realizados com concentrações menores para evitar a fitotoxidez.

  18. Effects of Helicoverpa armigera (Noctuidae, Lepidoptera) host stages on some developmental parameters of the uniparental endoparasitoid Meteorus pulchricornis (Braconidae, Hymenoptera).

    Liu, Ya-Hui; Li, Bao-Ping

    2008-04-01

    A single choice test was performed to examine developmental strategies in the uniparental endoparasitoid Meteorus pulchricornis and its host, the cotton bollworm Helicoverpa armigera. The results support the dome-shaped model in which the fitness functions are 'dome-shaped' relative to size (and age) of host at parasitism. Older and, hence, larger host larvae were simply not better hosts for the developing parasitoids. Although parasitoid size (measured as cocoon weight and adult hind tibia length) was positively correlated with host instars at parasitism, parasitoids developing in larger hosts (L5 and L6) suffered much higher mortality than conspecifics developing in smaller hosts (L2-L4). Furthermore, egg-to-adult development time in M. pulchricornis was significantly longer in older host larvae (L4-L6) than in the younger. Performance of M. pulchricornis, as indicated by fitness-related traits, strongly suggests that the L3 host is the most suitable for survival, growth and development of the parasitoid, followed by both L2 and L4 hosts; whereas, L1, L5 and L6 are the least favourable hosts. The oviposition tendency of M. pulchricornis, represented by parasitism level, was not perfectly consistent with the performance of the offspring; L2-L4 hosts, although with the same parasitism level, had offspring parasitoids with differences in fitness-related performance. Larval development in Helicoverpa armigera was usually suspended, but occasionally advanced, in the final instar.

  19. Transgenic Cotton Plants Expressing the HaHR3 Gene Conferred Enhanced Resistance to Helicoverpa armigera and Improved Cotton Yield.

    Han, Qiang; Wang, Zhenzhen; He, Yunxin; Xiong, Yehui; Lv, Shun; Li, Shupeng; Zhang, Zhigang; Qiu, Dewen; Zeng, Hongmei

    2017-08-30

    RNA interference (RNAi) has been developed as an efficient technology. RNAi insect-resistant transgenic plants expressing double-stranded RNA (dsRNA) that is ingested into insects to silence target genes can affect the viability of these pests or even lead to their death. HaHR3 , a molt-regulating transcription factor gene, was previously selected as a target expressed in bacteria and tobacco plants to control Helicoverpa armigera by RNAi technology. In this work, we selected the dsRNA- HaHR3 fragment to silence HaHR3 in cotton bollworm for plant mediated-RNAi research. A total of 19 transgenic cotton lines expressing HaHR3 were successfully cultivated, and seven generated lines were used to perform feeding bioassays. Transgenic cotton plants expressing ds HaHR3 were shown to induce high larval mortality and deformities of pupation and adult eclosion when used to feed the newly hatched larvae, and 3rd and 5th instar larvae of H. armigera . Moreover, HaHR3 transgenic cotton also demonstrated an improved cotton yield when compared with controls.

  20. Impacts of transgenic poplar-cotton agro-ecosystems upon target pests and non-target insects under field conditions.

    Zhang, D J; Liu, J X; Lu, Z Y; Li, C L; Comada, E; Yang, M S

    2015-07-27

    Poplar-cotton agro-ecosystems are the main agricultural planting modes of cotton fields in China. With increasing acres devoted to transgenic insect-resistant poplar and transgenic insect-resistant cotton, studies examining the effects of transgenic plants on target and non-target insects become increasingly important. We systematically surveyed populations of both target pests and non-target insects for 4 different combinations of poplar-cotton eco-systems over 3 years. Transgenic Bt cotton strongly resisted the target insects Fall webworm moth [Hyphantria cunea (Drury)], Sylepta derogata Fabrieius, and American bollworm (Heliothis armigera), but no clear impact on non-target insect cotton aphids (Aphis gossypii). Importantly, intercrops containing transgenic Pb29 poplar significantly increased the inhibitory effects of Bt cotton on Fall webworm moth in ecosystem IV. Highly resistant Pb29 poplar reduced populations of the target pests Grnsonoma minutara Hubner and non-target insect poplar leaf aphid (Chaitophorus po-pulialbae), while Fall webworm moth populations were unaffected. We determined the effects of Bt toxin from transgenic poplar and cotton on target and non-target pests in different ecosystems of cotton-poplar intercrops and identified the synergistic effects of such combinations toward both target and non-target insects.

  1. Over-expression of multiple cytochrome P450 genes in fenvalerate-resistant field strains of Helicoverpa armigera from north of China.

    Xu, Li; Li, Dongzhi; Qin, Jianying; Zhao, Weisong; Qiu, Lihong

    2016-09-01

    Pyrethroid resistance was one of the main reasons for control failure of cotton bollworm Helicoverpa armigera (Hübner) in China. The promotion of Bt crops decreased the application of chemical insecticides in controlling H.armigera. However, the cotton bollworm still kept high levels of resistance to fenvalerate. In this study, the resistance levels of 8 field-collected strains of H. armigera from north of China to 4 insecticides, as well as the expression levels of related P450 genes were investigated. The results of bioassay indicated that the resistance levels to fenvalerate in the field strains varied from 5.4- to 114.7-fold, while the resistance levels to lambda-cyhalothrin, phoxim and methomyl were low, which were ranged from 1.5- to 5.2-, 0.2- to 1.6-, and 2.9- to 8.3- fold, respectively, compared to a susceptible strain. Synergistic experiment showed that PBO was the most effective synergist in increasing the sensitivity of H. armigera to fenvalerate, suggesting that P450 enzymes were involved in the pyrethroid resistance in the field strains. The results of quantitative RT-PCR indicated that eight P450 genes (CYP332A1, CYP4L11, CYP4L5, CYP4M6, CYP4M7, CYP6B7, CYP9A12, CYP9A14) were all significantly overexpressed in Hejian1 and Xiajin1 strains of H. armigera collected in 2013, and CYP4L5 was significantly overexpressed in all the 6 field strains collected in 2014. CYP332A1, CYP6B7 and CYP9A12 had very high overexpression levels in all the field strains, indicating their important roles in fenvalerate resistance. The results suggested that multiple P450 genes were involved in the high-level fenvalerate-resistance in different field strains of H. armigera collected from north of China. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Spatial Distribution of Eggs of Alabama argillacea Hübner and Heliothis virescens Fabricius (Lepidoptera: Noctuidae on Bt and non-BtCotton

    TATIANA R. RODRIGUES

    2015-12-01

    Full Text Available ABSTRACT Among the options to control Alabama argillacea (Hübner, 1818 and Heliothis virescens (Fabricius, 1781 on cotton, insecticide spraying and biological control have been extensively used. The GM'Bt' cotton has been introduced as an extremely viable alternative, but it is yet not known how transgenic plants affect populations of organisms that are interrelated in an agroecosystem. For this reason, it is important to know how the spatial arrangement of pests and beneficial insect are affected, which may call for changes in the methods used for sampling these species. This study was conducted with the goal to investigate the pattern of spatial distribution of eggs of A. argillacea and H. virescens in DeltaOpalTM (non-Bt and DP90BTMBt cotton cultivars. Data were collected during the agricultural year 2006/2007 in two areas of 5,000 m2, located in in the district of Nova América, Caarapó municipality. In each sampling area, comprising 100 plots of 50 m2, 15 evaluations were performed on two plants per plot. The sampling consisted in counting the eggs. The aggregation index (variance/mean ratio, Morisita index and exponent k of the negative binomial distribution and chi-square fit of the observed and expected values to the theoretical frequency distribution (Poisson, Binomial and Negative Binomial Positive, showed that in both cultivars, the eggs of these species are distributed according to the aggregate distribution model, fitting the pattern of negative binomial distribution.

  3. Next-generation sequencing-based transcriptome analysis of Helicoverpa armigera Larvae immune-primed with Photorhabdus luminescens TT01.

    Zengyang Zhao

    Full Text Available Although invertebrates are incapable of adaptive immunity, immunal reactions which are functionally similar to the adaptive immunity of vertebrates have been described in many studies of invertebrates including insects. The phenomenon was termed immune priming. In order to understand the molecular mechanism of immune priming, we employed Illumina/Solexa platform to investigate the transcriptional changes of the hemocytes and fat body of Helicoverpa armigera larvae immune-primed with the pathogenic bacteria Photorhabdus luminescens TT01. A total of 43.6 and 65.1 million clean reads with 4.4 and 6.5 gigabase sequence data were obtained from the TT01 (the immune-primed and PBS (non-primed cDNA libraries and assembled into 35,707 all-unigenes (non-redundant transcripts, which has a length varied from 201 to 16,947 bp and a N50 length of 1,997 bp. For 35,707 all-unigenes, 20,438 were functionally annotated and 2,494 were differentially expressed after immune priming. The differentially expressed genes (DEGs are mainly related to immunity, detoxification, development and metabolism of the host insect. Analysis on the annotated immune related DEGs supported a hypothesis that we proposed previously: the immune priming phenomenon observed in H. armigera larvae was achieved by regulation of key innate immune elements. The transcriptome profiling data sets (especially the sequences of 1,022 unannotated DEGs and the clues (such as those on immune-related signal and regulatory pathways obtained from this study will facilitate immune-related novel gene discovery and provide valuable information for further exploring the molecular mechanism of immune priming of invertebrates. All these will increase our understanding of invertebrate immunity which may provide new approaches to control insect pests or prevent epidemic of infectious diseases in economic invertebrates in the future.

  4. Trans-generational desensitization and within-generational resensitization of a sucrose-best neuron in the polyphagous herbivore Helicoverpa armigera (Lepidoptera: Noctuidae)

    Ying Ma; Jingjing Li; Qingbo Tang; Xuening Zhang; Xincheng Zhao; Fengming Yan; Joop J. A. van Loon

    2016-01-01

    Dietary exposure of insects to a feeding deterrent substance for hours to days can induce habituation and concomitant desensitization of the response of peripheral gustatory neurons to such a substance. In the present study, larvae of the herbivore Helicoverpa armigera were fed on diets containing either a high, medium or low concentration of sucrose, a major feeding stimulant. The responsiveness of the sucrose-best neuron in the lateral sensilla styloconica on the galea was quantified. Resul...

  5. Population genetic structure of the cotton bollworm Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) in India as inferred from EPIC-PCR DNA markers.

    Behere, Gajanan Tryambak; Tay, Wee Tek; Russell, Derek Alan; Kranthi, Keshav Raj; Batterham, Philip

    2013-01-01

    Helicoverpa armigera is an important pest of cotton and other agricultural crops in the Old World. Its wide host range, high mobility and fecundity, and the ability to adapt and develop resistance against all common groups of insecticides used for its management have exacerbated its pest status. An understanding of the population genetic structure in H. armigera under Indian agricultural conditions will help ascertain gene flow patterns across different agricultural zones. This study inferred the population genetic structure of Indian H. armigera using five Exon-Primed Intron-Crossing (EPIC)-PCR markers. Nested alternative EPIC markers detected moderate null allele frequencies (4.3% to 9.4%) in loci used to infer population genetic structure but the apparently genome-wide heterozygote deficit suggests in-breeding or a Wahlund effect rather than a null allele effect. Population genetic analysis of the 26 populations suggested significant genetic differentiation within India but especially in cotton-feeding populations in the 2006-07 cropping season. In contrast, overall pair-wise F(ST) estimates from populations feeding on food crops indicated no significant population substructure irrespective of cropping seasons. A Baysian cluster analysis was used to assign the genetic make-up of individuals to likely membership of population clusters. Some evidence was found for four major clusters with individuals in two populations from cotton in one year (from two populations in northern India) showing especially high homogeneity. Taken as a whole, this study found evidence of population substructure at host crop, temporal and spatial levels in Indian H. armigera, without, however, a clear biological rationale for these structures being evident.

  6. A Multiplex Real-Time PCR Assay to Diagnose and Separate Helicoverpa armigera and H. zea (Lepidoptera: Noctuidae) in the New World.

    Gilligan, Todd M; Tembrock, Luke R; Farris, Roxanne E; Barr, Norman B; van der Straten, Marja J; van de Vossenberg, Bart T L H; Metz-Verschure, Eveline

    2015-01-01

    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.

  7. A Multiplex Real-Time PCR Assay to Diagnose and Separate Helicoverpa armigera and H. zea (Lepidoptera: Noctuidae in the New World.

    Todd M Gilligan

    Full Text Available 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.

  8. Sex pheromone in the moth Heliothis virescens is produced as a mixture of two pools: de novo and via precursor storage in glycerolipids.

    Foster, Stephen P; Anderson, Karin G; Casas, Jérôme

    2017-08-01

    Most species of moths use a female-produced volatile sex pheromone, typically produced via de novo fatty acid synthesis in a specialized gland, for communication among mates. While de novo biosynthesis of pheromone (DNP) is rapid, suggesting transient precursor acids, substantial amounts of pheromone precursor (and other) acids are stored, predominantly in triacylglycerols in the pheromone gland. Whether these stored acids are converted to pheromone later or not has been the subject of some debate. Using a tracer/tracee approach, in which we fed female Heliothis virescens U- 13 C-glucose, we were able to distinguish two pools of pheromone, in which precursors were temporally separated (after and before feeding on labeled glucose): DNP synthesized from a mixed tracer/tracee acetyl CoA pool after feeding, and pheromone made from precursor acids primarily synthesized before feeding, which we call recycled precursor fat pheromone (RPP). DNP titer varied from high (during scotophase) to low (photophase) and with presence/absence of pheromone biosynthesis activating neuropeptide (PBAN), in accord with native pheromone titer previously observed. By contrast, RPP was constant throughout the photoperiod and did not change with PBAN presence/absence. The amount of RPP (6.3-10.3 ng/female) was typically much lower than that of DNP, especially during the scotophase (peak DNP, 105 ng/female). We propose an integral role for stored fats in pheromone biosynthesis, in which they are hydrolyzed and re-esterified throughout the photoperiod, with a small proportion of liberated precursor acyl CoAs being converted to pheromone. During the sexually active period, release of PBAN results in increased flux of glucose (from trehalose) and hydrolyzed acids entering the mitochondria, producing acetyl CoA precursor for de novo fat and pheromone biosynthesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Synergism and Antagonism between Bacillus thuringiensis Vip3A and Cry1 Proteins in Heliothis virescens, Diatraea saccharalis and Spodoptera frugiperda

    Lemes, Ana Rita Nunes; Davolos, Camila Chiaradia; Legori, Paula Cristina Brunini Crialesi; Fernandes, Odair Aparecido; Ferré, Juan; Lemos, Manoel Victor Franco; Desiderio, Janete Apparecida

    2014-01-01

    Second generation Bt crops (insect resistant crops carrying Bacillus thuringiensis genes) combine more than one gene that codes for insecticidal proteins in the same plant to provide better control of agricultural pests. Some of the new combinations involve co-expression of cry and vip genes. Because Cry and Vip proteins have different midgut targets and possibly different mechanisms of toxicity, it is important to evaluate possible synergistic or antagonistic interactions between these two classes of toxins. Three members of the Cry1 class of proteins and three from the Vip3A class were tested against Heliothis virescens for possible interactions. At the level of LC50, Cry1Ac was the most active protein, whereas the rest of proteins tested were similarly active. However, at the level of LC90, Cry1Aa and Cry1Ca were the least active proteins, and Cry1Ac and Vip3A proteins were not significantly different. Under the experimental conditions used in this study, we found an antagonistic effect of Cry1Ca with the three Vip3A proteins. The interaction between Cry1Ca and Vip3Aa was also tested on two other species of Lepidoptera. Whereas antagonism was observed in Spodoptera frugiperda, synergism was found in Diatraea saccharalis. In all cases, the interaction between Vip3A and Cry1 proteins was more evident at the LC90 level than at the LC50 level. The fact that the same combination of proteins may result in a synergistic or an antagonistic interaction may be an indication that there are different types of interactions within the host, depending on the insect species tested. PMID:25275646

  10. Distribution and Metabolism of Bt-Cry1Ac Toxin in Tissues and Organs of the Cotton Bollworm, Helicoverpa armigera

    Zhuoya Zhao

    2016-07-01

    Full Text Available Crystal (Cry proteins derived from Bacillus thuringiensis (Bt have been widely used in transgenic crops due to their toxicity against insect pests. However, the distribution and metabolism of these toxins in insect tissues and organs have remained obscure because the target insects do not ingest much toxin. In this study, several Cry1Ac-resistant strains of Helicoverpa armigera, fed artificial diets containing high doses of Cry1Ac toxin, were used to investigate the distribution and metabolism of Cry1Ac in their bodies. Cry1Ac was only detected in larvae, not in pupae or adults. Also, Cry1Ac passed through the midgut into other tissues, such as the hemolymph and fat body, but did not reach the larval integument. Metabolic tests revealed that Cry1Ac degraded most rapidly in the fat body, followed by the hemolymph, peritrophic membrane and its contents. The toxin was metabolized slowly in the midgut, but was degraded in all locations within 48 h. These findings will improve understanding of the functional mechanism of Bt toxins in target insects and the biotransfer and the bioaccumulation of Bt toxins in arthropod food webs in the Bt crop ecosystem.

  11. Central projections of gustatory receptor neurons in the medial and the lateral sensilla styloconica of Helicoverpa armigera larvae.

    Qing-Bo Tang

    Full Text Available Food selection behavior of lepidopteran larvae is predominantly governed by the activation of taste neurons present in two sensilla styloconica located on the galea of the maxilla. In this study, we present the ultrastructure of the sensilla styloconica and the central projection pattern of their associated receptor neurons in larvae of the heliothine moth, Helicoverpa armigera. By means of light microscopy and scanning electron microscopy, the previous findings of two morphologically fairly similar sensilla comprising a socketed conic tip inserted into a large peg were confirmed. However, the peg size of the medial sensillum was found to be significantly bigger than that of the lateral sensillum. The sensory neurons derived from each sensillum styloconicum were mapped separately using anterograde staining experiments combined with confocal laser-scanning microscopy. For determining the afferents' target regions relative to each other, we reconstructed the labeled axons and placed them into a common reference framework. The sensory axons from both sensilla projected via the ipsilateral maxillary nerve to the suboesophageal ganglion and further through the ipsilateral circumoesophageal connective to the brain. In the suboesophageal ganglion, the sensory projections targeted two areas of the ipsilateral maxillary neuropil, one located in the ventrolateral neuromere and the other adjacent to the neuromere midline. In the brain, the axon terminals targeted the dorso-anterior area of the ipsilateral tritocerebrum. As confirmed by the three-dimensional reconstructions, the target regions of the neural projections originating from each of the two sensilla styloconica were identical.

  12. Central projections of gustatory receptor neurons in the medial and the lateral sensilla styloconica of Helicoverpa armigera larvae.

    Tang, Qing-Bo; Zhan, Huan; Cao, Huan; Berg, Bente G; Yan, Feng-Ming; Zhao, Xin-Cheng

    2014-01-01

    Food selection behavior of lepidopteran larvae is predominantly governed by the activation of taste neurons present in two sensilla styloconica located on the galea of the maxilla. In this study, we present the ultrastructure of the sensilla styloconica and the central projection pattern of their associated receptor neurons in larvae of the heliothine moth, Helicoverpa armigera. By means of light microscopy and scanning electron microscopy, the previous findings of two morphologically fairly similar sensilla comprising a socketed conic tip inserted into a large peg were confirmed. However, the peg size of the medial sensillum was found to be significantly bigger than that of the lateral sensillum. The sensory neurons derived from each sensillum styloconicum were mapped separately using anterograde staining experiments combined with confocal laser-scanning microscopy. For determining the afferents' target regions relative to each other, we reconstructed the labeled axons and placed them into a common reference framework. The sensory axons from both sensilla projected via the ipsilateral maxillary nerve to the suboesophageal ganglion and further through the ipsilateral circumoesophageal connective to the brain. In the suboesophageal ganglion, the sensory projections targeted two areas of the ipsilateral maxillary neuropil, one located in the ventrolateral neuromere and the other adjacent to the neuromere midline. In the brain, the axon terminals targeted the dorso-anterior area of the ipsilateral tritocerebrum. As confirmed by the three-dimensional reconstructions, the target regions of the neural projections originating from each of the two sensilla styloconica were identical.

  13. Characterization of lepidopteran-specific cry1 and cry2 gene harbouring native Bacillus thuringiensis isolates toxic against Helicoverpa armigera

    Showkat Ahmad Lone

    2017-09-01

    Full Text Available Bacillus thuringiensis (Bt based biopesticides are feasible alternatives to chemical pesticides. Here, we present the distribution of lepidopteran-specific cry1 and cry2 genes in native B. thuringiensis. Forty four out of 86 colonies were found to harbour crystals by phase contrast microscopy exhibiting a Bt index of 0.51. PCR analysis resulted in the amplification of cry1 in 24 and cry2 in 14 isolates. Twelve of the isolates showed presence of both cry1 and cry2, while 18 isolates did not show presence of either of the genes. Toxicity screening using spore-crystal mixtures against 2nd instar larvae of Helicoverpa armigera revealed that the isolates (50% were either mildly toxic or not toxic (36.36%, and only 13.63% were toxic. The results are interesting, particularly so because the same isolates were previously reported to contain lepidopteran specific vip3A genes also, hence can complement the toxicity of the isolates harbouring vip3A genes.

  14. Response of successive three generations of cotton bollworm, Helicoverpa armigera (Hübner), fed on cotton bolls, under elevated CO2

    2007-01-01

    The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera (Hübner), fed on cotton bolls grown under elevated CO2 (double-ambient vs. ambient) in open-top chambers were examined. Significant decreases in protein, total amino acid, water and nitrogen content and increases in free fatty acid were observed in cotton bolls. Changes in quality of cotton bolls affected the growth, development and food utilization of H. armigera. Significantly longer larval development duration in three successive generations and lower pupal weight of the second and third generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower fecundity was also found in successive three generations of H. armigera fed on cotton bolls grown under elevated CO2. The consumption per larva occurred significant increase in successive three generations and frass per larva were also significantly increased during the second and third generations under elevated CO2. Significantly lower relative growth rate, efficiency of conversion of ingested food and significant higher relative consumption rate in successive three generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower potential female fecundity, larval numbers and population consumption were found in the second and third generations of cotton bollworm fed on cotton bolls grown under elevated CO2. The integrative effect of higher larval mortality rate and lower adult fecundity resulted in significant decreases in potential population consumption in the latter two generations. The results show that elevated CO2 adversely affects cotton bolls quality, which indicates the potential population dynamics and potential population consumption of cotton bollworm will alleviate the harm to the plants in the future rising CO2 atmosphere.

  15. Heterologous expression of Helicoverpa armigera cytochrome P450 CYP6B7 in Pichia pastoris and interactions of CYP6B7 with insecticides.

    Zhao, Chunqing; Song, Genmiao; Duan, Hongxia; Tang, Tao; Wang, Chen; Qiu, Lihong

    2017-09-01

    Previous studies indicated that constitutive over-expression of cytochrome P450 CYP6B7 was involved in fenvalerate resistance in Helicoverpa armigera. In this study, the CYP6B7 gene from H. armigera (namely HaCYP6B7), was heterologously expressed in Pichia pastoris GS115. A vector pPICZA-HaCYP6B7 was constructed and transformed into P. pastoris GS115, the transformant of pPICZA-HaCYP6B7-GS115 was then cultured and induced by 1% (v/v) methanol and the heterologous expression of HaCYP6B7 protein in P. pastoris was confirmed by SDS-PAGE and western blot. Microsomes containing the expressed HaCYP6B7 showed activities against model substrate p-nitroanisole and 7-ethoxycoumarin, with p-nitroanisole O-demethylation (PNOD) and 7-ethoxycoumarin O-deethylation (ECOD) activities of 15.66- and 4.75-fold of the control, respectively. Moreover, it showed degradation activities against the insecticides bifenthrin, fenvalerate and chlorpyrifos, with clearance activities of 6.88-, 1.49- and 2.27-fold of the control, respectively. The interactions of HaCYP6B7 with insecticides were further confirmed by molecular docking in silico with binding scores of 5.450, 5.295 and 2.197 between putative HaCYP6B7 protein and bifenthrin, fenvalerate and chlorpyrifos, respectively. The results of present study provided more direct and important evidence on the role of HaCYP6B7 conferring pyrethroid resistance in H. armigera. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  16. Silencing of HaAce1 gene by host-delivered artificial microRNA disrupts growth and development of Helicoverpa armigera.

    Saini, Ravi Prakash; Raman, Venkat; Dhandapani, Gurusamy; Malhotra, Era Vaidya; Sreevathsa, Rohini; Kumar, Polumetla Ananda; Sharma, Tilak R; Pattanayak, Debasis

    2018-01-01

    The polyphagous insect-pest, Helicoverpa armigera, is a serious threat to a number of economically important crops. Chemical application and/or cultivation of Bt transgenic crops are the two strategies available now for insect-pest management. However, environmental pollution and long-term sustainability are major concerns against these two options. RNAi is now considered as a promising technology to complement Bt to tackle insect-pests menace. In this study, we report host-delivered silencing of HaAce1 gene, encoding the predominant isoform of H. armigera acetylcholinesterase, by an artificial microRNA, HaAce1-amiR1. Arabidopsis pre-miRNA164b was modified by replacing miR164b/miR164b* sequences with HaAce1-amiR1/HaAce1-amiR1* sequences. The recombinant HaAce1-preamiRNA1 was put under the control of CaMV 35S promoter and NOS terminator of plant binary vector pBI121, and the resultant vector cassette was used for tobacco transformation. Two transgenic tobacco lines expressing HaAce1-amiR1 was used for detached leaf insect feeding bioassays. Larval mortality of 25% and adult deformity of 20% were observed in transgenic treated insect group over that control tobacco treated insect group. The reduction in the steady-state level of HaAce1 mRNA was 70-80% in the defective adults compared to control. Our results demonstrate promise for host-delivered amiRNA-mediated silencing of HaAce1 gene for H. armigera management.

  17. Effectiveness of two insect growth regulators against Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) and Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) and their impact on population densities of arthropod predators in cotton in Pakistan.

    Gogi, Muhammad D; Sarfraz, Rana M; Dosdall, Lloyd M; Arif, Muhammad J; Keddie, Andrew B; Ashfaq, Muhammad

    2006-10-01

    Field efficacies of two insect growth regulators (IGRs) at two recommended application rates, buprofezin at 370 and 555 g AI ha(-1) and lufenuron at 37 and 49 g AI ha(-1), were determined against the sweet potato whitefly, Bemisia tabaci (Gennadius), and the cotton bollworm, Helicoverpa armigera (Hübner), in experimental plots of cotton at the Directorate of Cotton Research, Faisalabad, Pakistan. Adverse effects of the IGRs on populations of associated arthropod predators, namely geocorids, chrysopids, coccinellids, formicids and arachnids, were also assessed. Both IGRs significantly reduced populations of B. tabaci at each application rate 24, 48 and 72 h after treatment, and higher doses were more effective than lower doses. Buprofezin was not effective against H. armigera at any tested dose for any time of treatment in any spray. Lufenuron applied at 37 and 49 g AI ha(-1) effectively suppressed H. armigera populations, resulting in significant reductions in crop damage. At lower doses, both IGRs appeared safe to predator populations, which did not differ significantly in IGR-treated versus untreated control plots. Population densities of formicids and coccinellids were significantly lower at high concentrations of both IGRs in treatment plots, possibly as a result of reduced prey availability. The potential role of buprofezin and lufenuron for control of B. tabaci and H. armigera in a spray programme and the likelihood of direct toxic effects of IGRs on predatory fauna of cotton are discussed.

  18. The seesaw effect of winter temperature change on the recruitment of cotton bollworms Helicoverpa armigera through mismatched phenology.

    Reddy, Gadi V P; Shi, Peijian; Hui, Cang; Cheng, Xiaofei; Ouyang, Fang; Ge, Feng

    2015-12-01

    Knowing how climate change affects the population dynamics of insect pests is critical for the future of integrated pest management. Rising winter temperatures from global warming can drive increases in outbreaks of some agricultural pests. In contrast, here we propose an alternative hypothesis that both extremely cold and warm winters can mismatch the timing between the eclosion of overwintering pests and the flowering of key host plants. As host plants normally need higher effective cumulative temperatures for flowering than insects need for eclosion, changes in flowering time will be less dramatic than changes in eclosion time, leading to a mismatch of phenology on either side of the optimal winter temperature. We term this the "seesaw effect." Using a long-term dataset of the Old World cotton bollworm Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) in northern China, we tested this seesaw hypothesis by running a generalized additive model for the effects of the third generation moth in the preceding year, the winter air temperature, the number of winter days below a critical temperature and cumulative precipitation during winter on the demography of the overwintering moth. Results confirmed the existence of the seesaw effect of winter temperature change on overwintering populations. Pest management should therefore consider the indirect effect of changing crop phenology (whether due to greenhouse cultivation or to climate change) on pest outbreaks. As arthropods from mid- and high latitudes are actually living in a cooler thermal environment than their physiological optimum in contrast to species from lower latitudes, the effects of rising winter temperatures on the population dynamics of arthropods in the different latitudinal zones should be considered separately. The seesaw effect makes it more difficult to predict the average long-term population dynamics of insect pests at high latitudes due to the potential sharp changes in annual growth rates

  19. Acute, sublethal and combination effects of azadirachtin and Bacillus thuringiensis toxins on Helicoverpa armigera (Lepidoptera: Noctuidae) larvae.

    Singh, G; Rup, P J; Koul, Opender

    2007-08-01

    The efficacy of neem (1500 ppm azadirachtin (AI)), Delfin WG, a biological insecticide based on selected strain of Bacillus thuringiensis Berliner (Bt) subspecies kurstaki, and Cry1Ac protein, either individually or in combination, were examined against first to fourth instar Helicoverpa armigera (Hübner) larvae. Using an oral administration method, various growth inhibitory concentrations (EC) and lethal concentrations (LC) were determined for each bioagent. Combinations of sublethal concentrations of Bt spray formulation with azadirachtin at EC50 or EC95 levels not only enhanced the toxicity, but also reduced the duration of action when used in a mixture. The LC20 and LC50 values for Cry1Ac toxin were 0.06 and 0.22 microg ml-1, respectively. Bt-azadirachtin combinations of LC50+EC20 and LC50+EC50 result in 100% mortality. The mortality also was significant in LC20+EC20 and LC20+EC50 mixtures. These studies imply that the combined action is not synergistic but complimentary, with azadirachtin particularly facilitating the action of Bt. The Bt spray-azadirachtin combination is more economical than combinations that involve isolating the toxic protein, as the Bt spray formulations can be combined in a spray mixture with neem. These combinations may be useful for controlling bollworm populations that have acquired resistance to Bt as they may not survive the effect of mixture. Azadirachtin may be useful as a means of reducing the endotoxin concentrations in a mixture, to promote increased economic savings and further reduce the probability of resistance development to either insect control agent.

  20. Toxicidade e capacidade de ligação de proteínas Cry1 a receptores intestinais de Helicoverpa armigera (Lepidoptera: Noctuidae

    Isis Sebastião

    2015-11-01

    Full Text Available Resumo: O objetivo deste trabalho foi avaliar a toxicidade e a capacidade de ligação das proteínas Cry1Aa, Cry1Ab, Cry1Ac e Cry1Ca, de Bacillus thuringiensis, a receptores intestinais de Helicoverpa armigera. Realizou-se análise de ligação das proteínas ativadas às vesículas de membrana da microvilosidade apical (VMMA do intestino médio deH. armigera, além de ensaios de competição heteróloga para avaliar sua capacidade de ligação. Cry1Ac destacou-se como a proteína mais tóxica, seguida por Cry1Ab e Cry1Aa. A proteína Cry1Ca não foi tóxica às lagartas e, portanto, não foi possível determinar os seus parâmetros de toxicidade CL50 e CL90. As proteínas Cry1Aa, Cry1Ab e Cry1Ac são capazes de se ligar a um mesmo receptor nas membranas intestinais, o que aumenta o risco do desenvolvimento de resistência cruzada. Portanto, a utilização conjunta dessas proteínas deve ser evitada.

  1. Cotton bollworm, Helicoverpa armigera (Lepidoptera: Noctuidae): Large scale rearing and the effect of gamma radiation on selected life history parameters of this pest in China

    Lu Daguang; Liu Xiaohui; Hu Jiangguo; Wang Endong; He Qiulan; Li Yongjun

    2002-01-01

    Effective large scale rearing of the cotton bollworm, Helicoverpa armigera (Huebner), has been developed in China. A 'celled unit' system was developed to replace the traditional test tube for cotton bollworm laboratory rearing. Larvae are reared at 26.5 deg. C, ∼ 70% RH, and a long day photoperiod of 14L:10D. Pupae are harvested at about day 20. Percent adult emergence is between 89-93%, and adult females lay an average of 768 eggs. Under this rearing system one generation is completed in 40-42 days and percent pupation is about 66-71%. Mature Helicoverpa armigera female and male pupae were treated with different doses of gamma radiation and out-crossed with untreated mates. Mating ability of both sexes was not affected by radiation. Treated females were highly sterile and laid significantly fewer eggs than untreated controls. Females treated with 300 Gy were completely sterile, while females treated with 250 Gy and 200 Gy still had minimal residual fertility. (author)

  2. Transgenic plants over-expressing insect-specific microRNA acquire insecticidal activity against Helicoverpa armigera: an alternative to Bt-toxin technology.

    Agrawal, Aditi; Rajamani, Vijayalakshmi; Reddy, Vanga Siva; Mukherjee, Sunil Kumar; Bhatnagar, Raj K

    2015-10-01

    The success of Bt transgenics in controlling predation of crops has been tempered by sporadic emergence of resistance in targeted insect larvae. Such emerging threats have prompted the search for novel insecticidal molecules that are specific and could be expressed through plants. We have resorted to small RNA-based technology for an investigative search and focused our attention to an insect-specific miRNA that interferes with the insect molting process resulting in the death of the larvae. In this study, we report the designing of a vector that produces artificial microRNA (amiR), namely amiR-24, which targets the chitinase gene of Helicoverpa armigera. This vector was used as transgene in tobacco. Northern blot and real-time analysis revealed the high level expression of amiR-24 in transgenic tobacco plants. Larvae feeding on the transgenic plants ceased to molt further and eventually died. Our results demonstrate that transgenic tobacco plants can express amiR-24 insectice specific to H. armigera.

  3. Characterization of a digestive carboxypeptidase from the insect pest corn earworm (Helicoverpa armigera) with novel specificity towards C-terminal glutamate residues.

    Bown, David P; Gatehouse, John A

    2004-05-01

    Carboxypeptidases were purified from guts of larvae of corn earworm (Helicoverpa armigera), a lepidopteran crop pest, by affinity chromatography on immobilized potato carboxypeptidase inhibitor, and characterized by N-terminal sequencing. A larval gut cDNA library was screened using probes based on these protein sequences. cDNA HaCA42 encoded a carboxypeptidase with sequence similarity to enzymes of clan MC [Barrett, A. J., Rawlings, N. D. & Woessner, J. F. (1998) Handbook of Proteolytic Enzymes. Academic Press, London.], but with a novel predicted specificity towards C-terminal acidic residues. This carboxypeptidase was expressed as a recombinant proprotein in the yeast Pichia pastoris. The expressed protein could be activated by treatment with bovine trypsin; degradation of bound pro-region, rather than cleavage of pro-region from mature protein, was the rate-limiting step in activation. Activated HaCA42 carboxypeptidase hydrolysed a synthetic substrate for glutamate carboxypeptidases (FAEE, C-terminal Glu), but did not hydrolyse substrates for carboxypeptidase A or B (FAPP or FAAK, C-terminal Phe or Lys) or methotrexate, cleaved by clan MH glutamate carboxypeptidases. The enzyme was highly specific for C-terminal glutamate in peptide substrates, with slow hydrolysis of C-terminal aspartate also observed. Glutamate carboxypeptidase activity was present in larval gut extract from H. armigera. The HaCA42 protein is the first glutamate-specific metallocarboxypeptidase from clan MC to be identified and characterized. The genome of Drosophila melanogaster contains genes encoding enzymes with similar sequences and predicted specificity, and a cDNA encoding a similar enzyme has been isolated from gut tissue in tsetse fly. We suggest that digestive carboxypeptidases with sequence similarity to the classical mammalian enzymes, but with specificity towards C-terminal glutamate, are widely distributed in insects.

  4. Effects of Soil Salinity on the Expression of Bt Toxin (Cry1Ac and the Control Efficiency of Helicoverpa armigera in Field-Grown Transgenic Bt Cotton.

    Jun-Yu Luo

    Full Text Available An increasing area of transgenic Bacillus thuringiensis (Bt cotton is being planted in saline-alkaline soil in China. The Bt protein level in transgenic cotton plants and its control efficiency can be affected by abiotic stress, including high temperature, water deficiency and other factors. However, how soil salinity affects the expression of Bt protein, thus influencing the control efficiency of Bt cotton against the cotton bollworm (CBW Helicoverpa armigera (Hübner in the field, is poorly understood. Our objective in the present study was to investigate the effects of soil salinity on the expression of Bt toxin (Cry1Ac and the control efficiency of Helicoverpa armigera in field-grown transgenic Bt cotton using three natural saline levels (1.15 dS m-1 [low soil-salinity], 6.00 dS m-1 [medium soil-salinity] and 11.46 dS m-1 [high soil-salinity]. We found that the Bt protein content in the transgenic Bt cotton leaves and the insecticidal activity of Bt cotton against CBW decreased with the increasing soil salinity in laboratory experiments during the growing season. The Bt protein content of Bt cotton leaves in the laboratory were negatively correlated with the salinity level. The CBW populations were highest on the Bt cotton grown in medium-salinity soil instead of the high-salinity soil in field conditions. A possible mechanism may be that the relatively high-salinity soil changed the plant nutritional quality or other plant defensive traits. The results from this study may help to identify more appropriate practices to control CBW in Bt cotton fields with different soil salinity levels.

  5. Réponse des stades larvaires de Helicoverpa armigera (Hübner (Lepidoptera : Noctuidae à l'application de champignons entomopathogènes Metarhizium anisopliae et Beauveria bassiana

    Tamò, M.

    2012-01-01

    Full Text Available Response of the nymphs of Helicoverpa armigera (Hübner (Lepidoptera: Noctuidae to entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana. Two experiments on dose/mortality response between the instars of Helicoverpa armigera and two strains of entomopathogenic fungi, Metarhizium anisopliae (Met 31 and Beauveria bassiana (Bb 11 were carried out in laboratory conditions. In the first experiment, M. anisopliae Met 31 was tested on the third instar of H. armigera, while in the second experiment, both Met 31 and Bb 11 were tested on the fourth instar. In all the experiments, the following different doses of conidia per insect were used: 104, 105, 106, 107. The following parameters were measured: mortality and sporulation rates, the number of pupae formed and the number of adults that emerged. Abbott's formula was used to correct the treatment mortality rates. LD50 was determined using Cox-regression. For the third instar in experiment one, no significant difference was observed between high doses (106 and 107 conidia per insect. For instar L4, only the dose of 107 conidia per insect showed high mortality rates (74%. For the strain Bb 11, in spite of the variation observed between the mortality rates induced by high doses (106 and 107 conidia per insect, no significant difference was recorded at the 5% level. No mycosis was observed from cadavers resulting from lower doses when tested on L4. The control recorded the highest numbers of pupae and adults. These two parameters were related to the level of dosage: the higher the dose, the lower the numbers of pupae and adults that emerged. For all the strains of fungi used, whatever the larval stage of H. armigera, the dose/mortality response was significant.

  6. Distribution of 32P in laboratory colonies of Solenopsis invicta (Hymenoptera: Formicidae) after feeding on labeled Heliothis zeal (Lepidoptera: Noctuidae) eggs: an explanation of discrepancies encountered in field predation experiments

    Nuessly, G.S.; Sterling, W.L.

    1986-01-01

    Factors responsible for low recovery rates of radioactive Solenopsis invicta Buren following placement of 32 P-labeled Heliothis zea (Boddie) eggs on cotton in field predation tests were investigated using laboratory colonies of the ants. S. invicta workers became radioactive while handling labeled eggs by rupturing the egg chorion or by picking up labeled substances present on the surface of eggs. Foragers that removed the eggs from the plants picked up significantly more of the label than did workers that were sampled from the colonies between 12 and 72 h after egg introduction. Percentage of workers that became labeled over time was much lower with the solid live food than in other studies that used powdered food sources. Problems in finding labeled ants in the field may have been associated with low mean levels of 32 P per ant, together with difficulty in locating and isolating labeled ants from the population. Results indicate that egg predation rates estimated from counts per minute per predator have high variability, and suggest fairly large errors in estimates of eggs consumed per ant. Use of recovery rates of labeled predators to improve estimation of predation rates is discussed

  7. Análise da variabilidade genética de populações de Helicoverpa armigera (Lepidoptera: Noctuidae) ocorrendo em culturas de algodão e tomate - doi: 10.5102/ucs.v8i1.1056

    Queiroz, Paulo Roberto; Lima, Luzia Helena Corrêa

    2010-01-01

    Helicoverpa armigera é uma das principais pragas polífagas de distribuição mundial das culturas de interesse econômico. A identificação dessa espécie por meio molecular auxilia no estabelecimento do perfil genético, na caracterização e no monitoramento das populações desse inseto da ordem Lepidoptera. O objetivo desse trabalho foi estabelecer uma metodologia de extração de DNA para H. armigera, determinar perfis eletroforéticos e analisar a variabilidade genética entre as populações desse ins...

  8. Trans-generational desensitization and within-generational resensitization of a sucrose-best neuron in the polyphagous herbivore Helicoverpa armigera (Lepidoptera: Noctuidae).

    Ma, Ying; Li, Jingjing; Tang, Qingbo; Zhang, Xuening; Zhao, Xincheng; Yan, Fengming; van Loon, Joop J A

    2016-12-14

    Dietary exposure of insects to a feeding deterrent substance for hours to days can induce habituation and concomitant desensitization of the response of peripheral gustatory neurons to such a substance. In the present study, larvae of the herbivore Helicoverpa armigera were fed on diets containing either a high, medium or low concentration of sucrose, a major feeding stimulant. The responsiveness of the sucrose-best neuron in the lateral sensilla styloconica on the galea was quantified. Results showed the response of the sucrose-best neuron exposed to high-sucrose diets decreased gradually over successive generations, resulting in complete desensitization in the 5 th and subsequent generations. However, the sensitivity was completely restored in the ninth generation after neonate larvae were exposed to low-sucrose diet. These findings demonstrate phenotypic plasticity and exclude inadvertent artificial selection for low sensitivity to sucrose. No significant changes were found in the sensitivity of caterpillars which experienced low- or medium-sucrose diets over the same generations. Such desensitization versus re-sensitization did not generalise to the phagosimulant myo-inositol-sensitive neuron or the feeding deterrent-sensitive neuron. Our results demonstrate that under conditions of high sucrose availability trans-generational desensitization of a neuron sensitive to this feeding stimulant becomes more pronounced whereas re-sensitization occurs within one generation.

  9. Azadirachtin-A and tetrahydroazadirachtin-A concentrates: preparation, LC-MS characterization and insect antifeedant/IGR activity against Helicoverpa armigera (Hübner).

    Sharma, Vandana; Walia, Suresh; Dhingra, Swaran; Kumar, Jitendra; Parmar, Balraj S

    2006-10-01

    A 60% azadirachtin-A concentrate has been obtained through repeated precipitation with hexane from a methanolic solution of a 20% concentrate. Azadirachtin-A (90%) has been obtained by medium-pressure liquid chromatography of the 60% concentrate with an RP-18 column and a methanol + water (1 + 1 by volume) solvent system. Catalytic hydrogenation of the 60 and 90% azadirachtin concentrates yielded the corresponding tetrahydroazadirachtin concentrates. Dihydroazadirachtin and tetrahydroazadirachtin formed during the first 5 h of hydrogenation were identified by LC-ESI-MS on the basis of their unique mass fragmentation pattern. The efficacy of tetrahydroazadirachtin concentrates in inhibiting the feeding and growth of Helicoverpa armigera (Hübner) larvae has been compared with that of azadirachtin concentrates. They were in general more active and deterred larvae from feeding at all concentrations. Tetrahydroazadirachtin-A (90%) and azadirachtin-A (90%) with respective IC(50) values of 280 and 390 mg L(-1) were effective as insect growth regulators, while tetrahydroazadirachtin-A (90%) displayed higher antifeedant activity (AI(50) 14 mg L(-1)) against the test insect.

  10. No evidence for change in oviposition behaviour of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) after widespread adoption of transgenic insecticidal cotton.

    Zalucki, M P; Cunningham, J P; Downes, S; Ward, P; Lange, C; Meissle, M; Schellhorn, N A; Zalucki, J M

    2012-08-01

    Cotton growing landscapes in Australia have been dominated by dual-toxin transgenic Bt varieties since 2004. The cotton crop has thus effectively become a sink for the main target pest, Helicoverpa armigera. Theory predicts that there should be strong selection on female moths to avoid laying on such plants. We assessed oviposition, collected from two cotton-growing regions, by female moths when given a choice of tobacco, cotton and cabbage. Earlier work in the 1980s and 1990s on populations from the same geographic locations indicated these hosts were on average ranked as high, mid and low preference plants, respectively, and that host rankings had a heritable component. In the present study, we found no change in the relative ranking of hosts by females, with most eggs being laid on tobacco, then cotton and least on cabbage. As in earlier work, some females laid most eggs on cotton and aspects of oviposition behaviour had a heritable component. Certainly, cotton is not avoided as a host, and the implications of these finding for managing resistance to Bt cotton are discussed.

  11. Agricultural production - Phase 2. Indonesia. Insect ecology studies and insect pest control

    Butt, B.

    1992-01-01

    This document reviews the activities of the Pest Control Research Group in Indonesia. Pests under study are the diamondback moth (Plutella xylostella), the rice stem borer (Chilo suppressalis), the sugar cane borer (Chilo auricilius), bean flies (Agromyza spp.), tobacco insects (Heliothis armigera and Spodoptera litura) and cotton insects, especially the pink bollworm

  12. Essential oils-oriented fenvalerate analogues: syntheses, characterization and biological evaluation

    Su, H.; Li, H.

    2016-01-01

    A series of essential oils oriented ester derivatives have been designed, synthesized and characterized based on the skeleton of fenvalerate. The preliminary bioassay results indicated that some of the newly synthesized compounds showed better insecticidal activities against Pyrausta nubilalis and Heliothis armigera than that of the control trans-prallethrin chloride. (author)

  13. Determinant Factors in the Production of a Co-Occluded Binary Mixture of Helicoverpa armigera Alphabaculovirus (HearNPV) Genotypes with Desirable Insecticidal Characteristics

    Arrizubieta, Maite; Simón, Oihane; Williams, Trevor; Caballero, Primitivo

    2016-01-01

    A co-occluded binary mixture of Helicoverpa armigera nucleopolyhedrovirus genotypes HearSP1B and HearLB6 at a 1:1 ratio (HearSP1B+HearLB6) was selected for the development of a virus-based biological insecticide, which requires an efficient large-scale production system. In vivo production systems require optimization studies in each host-virus pathosystem. In the present study, the effects of larval instar, rearing density, timing of inoculation, inoculum concentration and temperature on the production of HearSP1B+HearLB6 in its homologous host were evaluated. The high prevalence of cannibalism in infected larvae (40–87%) indicated that insects require individual rearing to avoid major losses in OB production. The OB production of recently molted fifth instars (7.0 x 109 OBs/larva), combined with a high prevalence of mortality (85.7%), resulted in the highest overall OB yield (6.0 x 1011 OBs/100 inoculated larvae), compared to those of third or fourth instars. However, as inoculum concentration did not influence final OB yield, the lowest concentration, LC80 (5.5 x 106 OBs/ml), was selected. Incubation temperature did not significantly influence OB yield, although larvae maintained at 30°C died 13 and 34 hours earlier than those incubated at 26°C and 23°C, respectively. We conclude that the efficient production of HearSP1B+HearLB6 OBs involves inoculation of recently molted fifth instars with a LC80 concentration of OBs followed by individual rearing at 30°C. PMID:27732657

  14. The Use of F2 Screening for Detection of Resistance to Emamectin Benzoate, Chlorantraniliprole, and Indoxacarb in Australian Populations of Helicoverpa armigera (Lepidoptera: Noctuidae).

    Bird, L J; Drynan, L J; Walker, P W

    2017-04-01

    The ability to effectively detect changes in susceptibility to insecticides is an integral component of resistance management strategies and is highly dependent upon precision of methods deployed. Between 2013 and 2016, F2 screens were performed for detection of resistance alleles in Helicoverpa armigera (Hübner) to emamectin benzoate, chlorantraniliprole, and indoxacarb in major cropping regions of eastern Australia. Resistance to emamectin benzoate was not detected. There were low but detectable levels of survival at discriminating concentrations of chlorantraniliprole and indoxacarb. Alleles conferring an advantage to chlorantraniliprole were present at a frequency of 0.0027 (95% CI 0.0012-0.0064; n = 1,817). Alleles conferring an advantage to indoxacarb were present at a frequency of 0.027 (95% CI 0.020-0.035; n = 1,863). Complementation tests for allelism in six of seven positive indoxacarb tests indicated that resistance was due to alleles present at the same locus. The majority (88%) of lines that tested positive for indoxacarb resistance deviated from a model of recessive inheritance. Pheromone-caught male moths contributed significantly greater numbers of F2 lines compared with moths derived from field-collected eggs or larvae. There was no difference in the detectability of indoxacarb resistance in F2 lines from pheromone-caught moths compared with moths derived from immature stages collected from the field and reared to adult under laboratory conditions. Therefore, we recommend the use of pheromone traps for sourcing insects for F2 screening as a more cost- and time-efficient alternative to traditional methods of sampling. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. An independent occurrence of the chimeric P450 enzyme CYP337B3 of Helicoverpa armigera confers cypermethrin resistance in Pakistan.

    Rasool, Akhtar; Joußen, Nicole; Lorenz, Sybille; Ellinger, Renate; Schneider, Bernd; Khan, Sher Afzal; Ashfaq, Muhammad; Heckel, David G

    2014-10-01

    The increasing resistance level of insect pest species is a major concern to agriculture worldwide. The cotton bollworm, Helicoverpa armigera, is one of the most important pest species due to being highly polyphagous, geographically widespread, and resistant towards many chemical classes of insecticides. We previously described the mechanism of fenvalerate resistance in Australian populations conferred by the chimeric cytochrome P450 monooxygenase CYP337B3, which arose by unequal crossing-over between CYP337B1 and CYP337B2. Here, we show that this mechanism is also present in the cypermethrin-resistant FSD strain from Pakistan. The Pakistani and the Australian CYP337B3 alleles differ by 18 synonymous and three nonsynonymous SNPs and additionally in the length and sequence of the intron. Nevertheless, the activity of both CYP337B3 proteins is comparable. We demonstrate that CYP337B3 is capable of metabolizing cypermethrin (trans- and especially cis-isomers) to the main metabolite 4'-hydroxycypermethrin, which exhibits no intrinsic toxicity towards susceptible larvae. In a bioassay, CYP337B3 confers a 7-fold resistance towards cypermethrin in FSD larvae compared to susceptible larvae from the Australian TWB strain lacking CYP337B3. Linkage analysis shows that presence of CYP337B3 accounts for most of the cypermethrin resistance in the FSD strain; up-regulation of other P450s in FSD plays no detectable role in resistance. The presence or absence of CYP337B3 can be easily detected by a simple PCR screen, providing a powerful tool to rapidly distinguish resistant from susceptible individuals in the field and to determine the geographical distribution of this resistance gene. Our results suggest that CYP337B3 evolved twice independently by unequal crossing-over between CYP337B2 and two different CYP337B1 alleles. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Identificação morfológica e molecular de Helicoverpa armigera (Lepidoptera: Noctuidae e ampliação de seu registro de ocorrência no Brasil

    Alexandre Specht

    2013-06-01

    Full Text Available O objetivo deste trabalho foi descrever métodos para a caracterização morfológica e molecular de Helicoverpa armigera e ampliar o registro de ocorrência da praga no Brasil. As mariposas foram obtidas de lagartas coletadas nas culturas de algodão, milho e soja, com uso de armadilhas luminosas. As coletas foram realizadas na Bahia, no Distrito Federal, no Mato Grosso e no Paraná. A identificação foi baseada na genitália masculina e nas análises das sequências dos genes mitocondriais do citocromo B e da região cox1-tRNALeu-cox2. A genitália masculina foi comparada com as descrições morfológicas na literatura, e as sequências de genes, com as depositadas no GenBank. Ambas as análises confirmaram a presença de H. armigera nos locais de coleta. Ampliou-se o registro de ocorrência da praga para a região Sul do país.

  17. Assessment of beneficial role of an insectivorous bird, jungle babbler (Turdoides striatus predation, on Helicoverpa armigera infesting pigeon pea (Cajanus cajan crop

    Bharucha Bhavna

    2010-06-01

    Full Text Available Jungle babbler (Turdoides striatus, a widely spread sub-tropical insectivorous passerine is considered beneficial to agro-ecosystem, as they devour voraciously on insect matter especially Helicoverpa armigera, the gram pod borer, a notorious pest infesting and causing heavy loses to crops like pigeon pea (Cajanus cajan which is a vital crop of semi-arid tropical and subtropical farming system, providing high quality vegetable protein. Helicoverpa is known to feed on flowers, pods, and seeds and is the most important biotic constraint affecting pigeon pea yields. Jungle babblers have a peculiar foraging style which helps expose the Helicoverpa larvae as well as pupae through various phenological stages of pigeon pea. For comparative assessment of their beneficial role and as a possible bio control agent, in Baroda city (State of Gaujarat, India, was studied, two crops of pigeon pea (insecticide treated and untreated (control were selected. In both treated and control crops, the number of jungle babblers were maximum in pigeon pea fields during october and november in both small pod stage and large pod stage which had heavy infestation of Helicoverpa. Least number of birds was seen during the flowering stage in September. Later in treatment crop three applications of Dunnate and Monocrotophos insecticide spray was done after which the pest population decreased which is reflected in number of birds in the field, while the bird number in control crops grew since insecticide spray was not done and number of larvae increased with the stage of the crop. Along with the main crop pigeon pea, comparative study was also done to see the food preference by these birds in crops like sorghum, maize, cow pea and ploughed and unploughed fields. Maximum number of birds was seen in unploughed field and least in sorghum suggesting that Helicoverpa is preferred food over sorghum grains thus pigeon pea

  18. Assessment of beneficial role of an insectivorous bird, jungle babbler (Turdoides striatus predation, on Helicoverpa armigera infesting pigeon pea (Cajanus cajan crop Evaluación del rol benéfico de Turdoides striatus como predator de Helicoverpa armigera en el cultivo de guandul (Cajanus cajan

    Bhavna Bharucha

    2010-04-01

    Full Text Available Jungle babbler (Turdoides striatus, a widely spread sub-tropical insectivorous passerine is considered beneficial to agro-ecosystem, as they devour voraciously on insect matter especially Helicoverpa armigera, the gram pod borer, a notorious pest infesting and causing heavy loses to crops like pigeon pea (Cajanus cajan which is a vital crop of semi-arid tropical and subtropical farming system, providing high quality vegetable protein. Helicoverpa is known to feed on flowers, pods, and seeds and is the most important biotic constraint affecting pigeon pea yields. Jungle babblers have a peculiar foraging style which helps expose the Helicoverpa larvae as well as pupae through various phenological stages of pigeon pea. For comparative assessment of their beneficial role and as a possible bio control agent, in Baroda city (State of Gaujarat, India, was studied, two crops of pigeon pea (insecticide treated and untreated (control were selected. In both treated and control crops, the number of jungle babblers were maximum in pigeon pea fields during october and november in both small pod stage and large pod stage which had heavy infestation of Helicoverpa. Least number of birds was seen during the flowering stage in September. Later in treatment crop three applications of Dunnate and Monocrotophos insecticide spray was done after which the pest population decreased which is reflected in number of birds in the field, while the bird number in control crops grew since insecticide spray was not done and number of larvae increased with the stage of the crop. Along with the main crop pigeon pea, comparative study was also done to see the food preference by these birds in crops like sorghum, maize, cow pea and ploughed and unploughed fields. Maximum number of birds was seen in unploughed field and least in sorghum suggesting that Helicoverpa is preferred food over sorghum grains thus pigeon pea and sorghum can be used as mixed crops to protect the crop from

  19. Métodos de analise dos danos da lagarta da espiga¹, em médias de gerações envolvendo IAC Maya e Zapalote Chico Method for analysis of damage of the corn earworm heliothis zea in generation means from IAC Maya and Zapalote Chico

    Jorge Alberto Marques Rezende

    1982-01-01

    Full Text Available O milho Zapalote Chico 2451 (ZC 2451, referido na literatura como a melhor fonte de resistência à lagarta da espiga, Heliothis zea (Boddie, 1850, e o IAC Maya XII foram observados em condições de campo, juntamente com as gerações F1, e F2 resultantes do cruzamento de ambos, bem como os respectivos retrocruzamentos da população F1, para cada um dos pais, a fim de estudar métodos de análises de dados obtidos através da escala de dano revista por WIDSTROM e, conseqüentemente, fornecer subsídios para trabalhos de estudo da herança da resistência envolvendo esse cruzamento. Para analisar os dados, dividiram-se as notas de dano em quatro classes distintas agrupadas duas a duas, zero mais 1 e > 2, e zero e > 1, e aplicou-se o método do quiquadrado (c2 para verificar qual divisão melhor se ajustava. Os resultados revelaram que o grupo das classes zero mais 1 e > 2 apresentou melhor uniformidade dos dados entre as repetições dentro de cada tratamento. A análise da variância para cada classe de dano, separadamente, apresentou valores de F altamente significativos para as classes zero e zero mais 1, enquanto para as classes > 1 e > 2, os mesmos não permitiram diferenciar os tratamentos. Entre as classes zero e zero mais 1, esta última revelou maior significância e melhor precisão dos dados. O milho ZC 2451, quando comparado com a variedade IAC Maya XII, exibiu boa resistência à lagarta da espiga nas condições de Campinas (SP, resistência essa relacionada com fatores de não preferência e/ou antibiose, devido ã maior porcentagem de espigas não danificadas do ZC 2451.The line Zapalote Chico 2451 (ZC 2451 resistant to the corn earworm, Heliothis zea, the commercial synthetic Brazilian variety IAC Maya XII, the F1 and F2 obtained with their cross, and the two back crosses between the F1 and both parents, were planted in the field in a randomized block with 10 replications. The earworm damage done to the ears was graded

  20. Análise da variabilidade genética de populações de Helicoverpa armigera (Lepidoptera: Noctuidae ocorrendo em culturas de algodão e tomate - doi: 10.5102/ucs.v8i1.1056

    Paulo Roberto Queiroz

    2010-10-01

    Full Text Available Helicoverpa armigera é uma das principais pragas polífagas de distribuição mundial das culturas de interesse econômico. A identificação dessa espécie por meio molecular auxilia no estabelecimento do perfil genético, na caracterização e no monitoramento das populações desse inseto da ordem Lepidoptera. O objetivo desse trabalho foi estabelecer uma metodologia de extração de DNA para H. armigera, determinar perfis eletroforéticos e analisar a variabilidade genética entre as populações desse inseto-praga. Os cinco iniciadores de RAPD produziram fragmentos de DNA que revelaram uma similaridade genética inferior a 80% entre as dez populações no dendrograma que foi gerado. Os resultados obtidos com as análises de variância molecular (AMOVA revelaram que a elevada fonte de variação genética foi o resultado da variabilidade dentro de cada população. As causas que levaram a essa elevada variabilidade precisam ser mais bem estudadas nos países onde a praga ocorre.

  1. Design, Synthesis, and Insecticidal Activity of Some Novel Diacylhydrazine and Acylhydrazone Derivatives

    Jialong Sun

    2015-03-01

    Full Text Available In this study a series of diacylhydrazine and acylhydrazone derivatives were designed and synthesized according to the method of active group combination and the principles of aromatic group bioisosterism. The structures of the novel derivatives were determined on the basis on 1H-NMR, IR and ESI-MS spectral data. All of the compounds were evaluated for their in vivo insecticidal activity against the third instar larvae of Spodoptera exigua Hiibner, Helicoverpa armigera Hubner, Plutella xyllostella Linnaeus and Pieris rapae Linne, respectively, at a concentration of 10 mg/L. The results showed that all of the derivatives displayed high insecticidal activity. Most of the compounds presented higher insecticidal activity against S. exigua than the reference compounds tebufenozide, metaflumizone and tolfenpyrad, and approximately identical insecticidal activity against H. armigera, P. xyllostella and P. rapae as the references metaflumizone and tolfenpyrad.

  2. Screening of tomato genotypes for resistance to tomato fruit borer (helicoverpa armiger hubner) in Pakistan

    Sajjad, M.; Ashfaq, M.; Suhail, A.

    2011-01-01

    Tomato genotypes viz., Roma Local, Rio Grande, Tanja, Chico III, Long Tipped, Red-Top, FS-8001, FS-8002, Tropic, Pakit, Peelo, NARC-1, Roma VFN, Pant Bahr, Ebein, Nova Mech, Rockingham, Nagina, Shalkot-96, Pomodoro, Manik, Gressilesse, Nadir, Early Mech, Tommy, Pusha Rubi, Tropic boy, Big Long, Sahil, Sun 6002, Money-Maker and Royesta were evaluated to screen out the suitable resistant/susceptible genotypes against the fruit borer in Pakistan. The results imparted that the percentage of fruit infestation and larval population per plant on tested genotypes of tomato varied significantly. Roma VF, NARC-1 and FS-8002 were categorized as susceptible genotypes with fruit infestation (37.69%, 37.08% and 36.41%, respectively) and larval population per plant (1.02%, 1.02% and 0.84 %, respectively). Whereas, the genotypes Sahil, Pakit and Nova Mecb had fruit infestation (12.30%, 13.14% and 13.96%, respectively) and larval population per plant (0.42%, 0.42% and 0.43%, respectively) and declared as resistant genotypes to tomato fruit borer. Lower values of host plant susceptibility indices (HPSI) were recorded on resistant genotypes. Sahil, Pakit and Nova Mecb could be used as a source of resistance for developing tomato genotypes resistant to tomato fruit borer. (author)

  3. THE INFLUENCE OF ABIOTIC FACTORS ON THE PRESENCE OF EUROPEAN CORN BORER (Ostrinia nubilalis Hubner

    Ankica Sarajlić

    2015-12-01

    Full Text Available Field experiments with natural population of European corn borer (ECB were conducted in three vegetation seasons (2012-2014 at Agricultural Institute in Osijek. The experiment was set up in a randomized block design as split-split plot method, with three repetitions. This plot has been constantly maize - soybean rotation for already 15 years. It was a 3x3x4 factorial experiment with three irrigation levels (A1- non-irrigated (only natural precipitation, A2-from 60% to 80% field water capacity - FWC and A3-from 80% to100% FWC, three nitrogen fertilizer levels (B1-0, B2-100 and B3-200 kg N/ha and four different genotypes (C1-0SSK 596; C2-0SSK 617; C3-0SSK 602 and C4-0SSK 552.The aim of this study was to determine the effect of different levels of irrigation, nitrogen fertilization and genotypes on occurrence and damage of maize plants by the European corn borer larvae and relation between leaf feeding larvae with nitrogen and silicon concentration as well as C/N ratio. At the end of each growing season, ten maize plants from each variant were cut. Ear weight for each specific plant (g, tunnel length (cm, number of larvae in stalk, number of larvae in the ear shank, ear shank damage (cm and total number of larvae in maize plantwere determined. In silking stage (middle of July ten leaves (below the ear, from 10 maize plants were sampled on each variant. Nitrogen, carbon and silicon concentrations were determined in maize leaf (% and C/N ratio calculated. In 2014, a significantly lower ECB attack was determined taking into account lower temperatures and higher amount of precipitate compared to the previous years. Dominance of Z-type European corn borer on pheromone traps in the area of eastern Slavonia was confirmed. Increasing the level of soil water content, damage from larvae was reduced and increasing the level of nitrogen fertilization feeding activity was increased. We have confirmed different hybrid resistance in regards to damage from larvae, so C4 (OSSK 552 genotype was the most resistant while C1 (OSSK 596 was the most susceptible. Concentration of nitrogen and silicon in a maize leaf was in negative correlation as well as nitrogen concentration and C/N ratio. Hybrid resistance didn't entirely depend on nitrogen and silicon concentrations, even though there was greater damage on most hybrids with higher concentration of nitrogen, while damage was reduced with higher concentration of silicon.

  4. Radioimmunoassay analysis of baculovirus granulins and polyhedrins

    Summers, M.D.; Hoops, P.

    1980-01-01

    Granulin and polyhedrin proteins were purified by preparative sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis from the baculoviruses Autographa californica, Rachiplusia ou, Heliothis zea, Heliothis armigera. Trichoplusia ni, and Spodoptera frugiperda. Antisera were raised against Autographa californica (Ac) polyhedrin and Trichoplusia ni (Tn) granulin and analyzed for homologous and heterologous immunoreactivity by immunodiffusion and radioimmunoassay (RIA). Ac polyhedrin and Tn granulin antisera recognized antigenic determinants on several baculovirus polyhedrin and granulin proteins even though the heterologous proteins had different immunoreactivities when compared by competition radioimmunoassay. Antigenic differences among granulin and polyhedrin proteins were also detected by altered slopes of the competition reaction curves. Antiserum raised against Ac polyhedrin which was purified in the presence of SDS was tested by competition RIA for its ability to detect and react with native polyhedrin produced in the infected TN-368 cells. Ac polyhedrin antiserum had similar if not identical ability to bind to native polyhedrin and to polyhedrin purified in the presence of SDS

  5. First results of the application of a new Neemazal powder formulation in hydroponics against different pest insects.

    Hummel, Edmund; Kleeberg, Hubertus

    2002-01-01

    NeemAzal PC (0.5% Azadirachtin) is a new standardised powder formulation from the seed kernels of the tropical Neem tree (Azadirachta indica A. Juss) with an inert carrier. First experiments with beans--as a model-system for hydroponics--show that active ingredient is taken up by the plants through the roots and is transported efficiently with the plant sap to the leaves. After application of NeemAzal PC solution (0.01-1%) to the roots sucking (Aphis fabae Hom., Aphididae) and free feeding (Heliothis armigera Lep., Noctuidae) pest insects can be controlled efficiently. The effects are concentration and time dependent.

  6. Variasi Kebugaran Jenis/Strain Trichogramma pada Telur Plutella xylostella (L. (Lepidoptera: Plutellidae

    Siti Herlinda

    2005-07-01

    Full Text Available Laboratory experiments were conducted to evaluate fitness traits of trichogrammatid species/strains reared on eggs of the diamondback moth, Plutella xylostella (L.. The experiments used eleven trichogrammatid species/strains collected from different host species and locations. They were Trichogrammatoidea cojuangcoi Nagaraja collected from parasitized P. xylostella eggs in Jarai, Muarasiban, Kerinjing, and Bogar, Trichogrammatoidea sp. A and B collected from parasitized Helicoverpa armigera (Hubner eggs in Bogor, Trichogrammatoidea armigera Nagaraja collected from parasitized H. armigera eggs in Bogor, Trichogramma chilonis Ishii, Trichogramma japanicum Ashmead, Trichogramma australicum Girault, and Trichogrammatoidea nana (Zehntner collected from parasitized Chilo sp. eggs in Cinta Manis, South Sumatera. When a female of Trichogramma was constantly exposed to 100 P. xylostella eggs per day throughout her lifetime, T. cojuangcoi from Jarai produced more parasitized host eggs (50.67% and progenies (50.67 adults/female compared to other species/strains. Sex ratio was predominantly female, the most female progenies were produced ( 38 adults/ female by T. cojuangcoi from Jarai. There were no significant differences in larval (0-3.27% and pupal (0-3.75% mortality of all species/strains. Survival emerging adults of T. japanicum (90.24% were significantly lower than those of other species/strains. These data showed that T. cojuangcoi from Jarai could be developed as biocontrol agents of P. xylostella.

  7. The natural refuge policy for Bt cotton (Gossypium L. in Pakistan – a situation analysis

    Muhammad Sajjad Ali

    2013-07-01

    Full Text Available Bt cotton (event Cry1Ac was formally commercialized in Pakistan in 2010. However, there has been an increasing trend of planting unauthorized Bt cotton germplasm in farmers' fields since 2003 with a high rate of adoption in the core cotton areas especially in the province Punjab. The transgenic cotton technology has provided the growers with substantial economic benefits and has reduced their dependence on pesticides for pest control, especially against Helicoverpa armigera (Hubner. However, keeping in view the capacity of this insect to develop resistance against novel chemical formulations, it is easily speculated that Bt toxin, too, is no exception. Refuge crop policy for mono transgenic crop events has helped in delaying the rate of resistance evolution in the target pests. Thus, in Pakistan, where planting of structured refuge crops along Bt cotton fields is not mandatory, the effectiveness and durability of Bt cotton technology may decrease due to a number of factors which are discussed in this review.

  8. Design, Synthesis and Insecticidal Activity of Novel Phenylurea Derivatives

    Jialong Sun

    2015-03-01

    Full Text Available A series of novel phenylurea derivatives were designed and synthesized according to the method of active groups linkage and the principle of aromatic groups bioisosterism in this study. The structures of the novel phenylurea derivatives were confirmed based on ESI-MS, IR and 1H-NMR spectral data. All of the compounds were evaluated for the insecticidal activity against the third instars larvae of Spodoptera exigua Hiibner, Plutella xyllostella Linnaeus, Helicoverpa armigera Hubner and Pieris rapae Linne respectively, at the concentration of 10 mg/L. The results showed that all of the derivatives displayed strong insecticidal activity. Most of the compounds presented higher insecticidal activity against S. exigua than the reference compounds tebufenozide, chlorbenzuron and metaflumizone. Among the synthesized compounds, 3b, 3d, 3f, 4b and 4g displayed broad spectrum insecticidal activity.

  9. Safety assessment and detection method of genetically modified Chinese Kale (Brassica oleracea cv. alboglabra ).

    Lin, Chih-Hui; Lu, Chien-Te; Lin, Hsin-Tang; Pan, Tzu-Ming

    2009-03-11

    Sporamins are tuberous storage proteins and account for 80% of soluble protein in sweet potato tubers with trypsin-inhibitory activity. The expression of sporamin protein in transgenic Chinese kale (line BoA 3-1) conferred insecticidal activity toward corn earworm [ Helicoverpa armigera (Hubner)] in a previous report. In this study, we present a preliminary safety assessment of transgenic Chinese kale BoA 3-1. Bioinformatic and simulated gastric fluid (SGF) analyses were performed to evaluate the allergenicity of sporamin protein. The substantial equivalence between transgenic Chinese kale and its wild-type host has been demonstrated by the comparison of important constituents. A reliable real-time polymerase chain reaction (PCR) detection method was also developed to control sample quality. Despite the results of most evaluations in this study being negative, the safety of sporamin in transgenic Chinese kale BoA 3-1 was uncluded because of the allergenic risk revealed by bioinformatic analysis.

  10. Methoprene and synergized pyrethrins as an aerosol treatment to control Plodia interpunctella (Hubner), the Indian meal moth (Lepidoptera: Pyralidae)

    Aerosol insecticides (also known as ULV or fogging treatments) delivered through an ultra-low volume application system, are available commercially to control insect pests such as Plodia interpunctella Hübner, the Indianmeal moth. However, little is known about the susceptibility of eggs of P. inter...

  11. Bracovirus derived genes in the genome of Spodoptera exigua Hubner (Lepidoptera: Noctuidae) and their role in host susceptibility to pathogens

    Gasmi, Laila

    2015-01-01

    La asociación entre los himenópteros parasitoides, polydnavirus (PDV) y lepidópteros representa un modelo interesante para estudiar la transferencia horizontal de genes. Está bien documentado que miles de himenópteros parasitoides pertenecientes a las familias Braconidae e Ichneumonidae han domesticado virus simbióticos denominados respectivamente Bracovirus o Ichnovirus. El virus se inyecta junto con los huevos del parásito en el hemocele del lepidóptero huésped, donde se expresan proteínas ...

  12. Microbial agents against Helicoverpa armigera: Where are we and ...

    SAM

    2014-04-30

    Apr 30, 2014 ... feed and fibre around the world. Different approaches namely: .... biocontrol agent from the fungus Trichoderma harzianum was also evaluated .... the antibiotic biosynthetic gene transfer (Baltz, 2005). Overall 23,000 bioactive ...

  13. Recent advances of rearing cabinet instrumentation and control system for insect stock culture

    Hermawan, Wawan; Kasmara, Hikmat; Melanie, Panatarani, Camellia; Joni, I. Made

    2017-01-01

    Helicoverpa armigera (Hubner) is one of a serious pest of horticulture in Indonesia. Helicoverpa armigera Nuclear Polyhedrovirus (HaNPV) has attracted interest for many researchers as a pest control for larvae of this species. Currently, we investigating the agrochemical formulations of HaNPV by introducing nanotechnology. Thus it is required an acceptable efficiency of insect stock cultures equipped with advance instruments to resolve the difficulties on insect stock seasons dependency. In addition, it is important to improve the insect survival with the aid of artificial natural environment and gain high insect production. This paper reports the rearing cabinet used as preparation of stock culture includes air-conditioning system, lighting, i.e. day and night control, and the main principles on recent technical and procedural advances apparatus of the system. The rearing system was moveable, designed and build by allowing air-conditioned cabinet for rearing insects, air motion and distribution as well as temperature and humidity being precisely controlled. The air was heated, humidified, and dehumidified respectively using a heater and ultrasonic nebulizer as actuators. Temperature and humidity can be controlled at any desired levels from room temperature (20°C) to 40 ± 1°C and from 0 to 80% RH with an accuracy of ±3% R.H. It is concluded that the recent design has acceptable performance based on the defined requirement for insect rearing and storage.

  14. Role of different weather conditions on the incidence and development of american bollworm

    Khaliq, A.; Subhani, M.N.; Hassan, S.W.; Murtaza, M.A.

    2008-01-01

    Studies were conducted at Nuclear Institute for Agriculture and biology (NIAB). Faisalabad on ten advance genotypes of cotton Viz,. BH-121, NIAB KRISHMA, DNH-137, VH-142, BH-125. MNH-635, SLH-267, FNH-245, CRIS-467 and CRIS-82, to see the role of different weather condition on the incidence and development of American bollworm (Heliothis armigera) infestation and coefficient of correlation among these factors and American bollworm infestation. Trial were laid out using Randomized Complete Block Design (RCBD) with four replications. Finally data were subject to the statistical analysis and for correlation studies between weather factors and percent American boll temperature infestation. Temperature and relative humidity were correlated positively and rainfall effected negatively to the infestation of American bollworm on squares and for green bolls temperature was positively correlated while relative humidity and rainfall negatively with the percent American bollworm infestation in advance -genotypes of cotton under unsprayed condition. (author)

  15. Differential arrestment of Trichogramma wasps to extreme sex pheromone types of the noctuid moth Heliothis virescens

    Xu, J.; Huigens, M.E.; Orr, D.; Groot, A.T.

    2014-01-01

    1. Chemical espionage in nature may occur when predators or parasitoids home in on animal or plant communication signals. Parasitoid wasps are known to use pheromones emitted by adults hosts to locate host eggs, larvae or pupae. The response of Trichogramma egg parasitoids to a synthetic sex

  16. p13 from group II baculoviruses is a killing-associated gene

    Yipeng Qi

    2012-12-01

    Full Text Available p13 gene was first described in Leucania separata multinuclearpolyhedrosis virus (Ls-p13 several years ago, but the functionof P13 protein has not been experimentally investigated todate. In this article, we indicated that the expression of p13from Heliothis armigera single nucleocapsid nucleopolyhedrovirus(Ha-p13 was regulated by both early and late promoter.Luciferase assay demonstrated that the activity of Ha-p13promoter with hr4 enhancer was more than 100 times inheterologous Sf9 cells than that in nature host Hz-AM1 cells.Both Ls-P13 and Ha-P13 are transmembrane proteins. Confocalmicroscopic analysis showed that both mainly located in thecytoplasm membrane at 48 h. Results of RNA interferenceindicated that Ha-p13 was a killing-associated gene for hostinsects H. armigera. The AcMNPV acquired the mentionedkilling activity and markedly accelerate the killing rate whenexpressing Ls-p13. In conclusion, p13 is a killing associatedgene in both homologous and heterologous nucleopolyhedrovirus.

  17. Reduced levels of membrane-bound alkaline phosphatase are common to lepidopteran strains resistant to Cry toxins from Bacillus thuringiensis.

    Juan Luis Jurat-Fuentes

    Full Text Available Development of insect resistance is one of the main concerns with the use of transgenic crops expressing Cry toxins from the bacterium Bacillus thuringiensis. Identification of biomarkers would assist in the development of sensitive DNA-based methods to monitor evolution of resistance to Bt toxins in natural populations. We report on the proteomic and genomic detection of reduced levels of midgut membrane-bound alkaline phosphatase (mALP as a common feature in strains of Cry-resistant Heliothis virescens, Helicoverpa armigera and Spodoptera frugiperda when compared to susceptible larvae. Reduced levels of H. virescens mALP protein (HvmALP were detected by two dimensional differential in-gel electrophoresis (2D-DIGE analysis in Cry-resistant compared to susceptible larvae, further supported by alkaline phosphatase activity assays and Western blotting. Through quantitative real-time polymerase chain reaction (qRT-PCR we demonstrate that the reduction in HvmALP protein levels in resistant larvae are the result of reduced transcript amounts. Similar reductions in ALP activity and mALP transcript levels were also detected for a Cry1Ac-resistant strain of H. armigera and field-derived strains of S. frugiperda resistant to Cry1Fa. Considering the unique resistance and cross-resistance phenotypes of the insect strains used in this work, our data suggest that reduced mALP expression should be targeted for development of effective biomarkers for resistance to Cry toxins in lepidopteran pests.

  18. in silico identification of cross affinity towards Cry1Ac pesticidal protein with receptor enzyme in Bos taurus and sequence, structure analysis of crystal proteins for stability.

    Ebenezer, King Solomon; Nachimuthu, Ramesh; Thiagarajan, Prabha; Velu, Rajesh Kannan

    2013-01-01

    Any novel protein introduced into the GM crops need to be evaluated for cross affinity on living organisms. Many researchers are currently focusing on the impact of Bacillus thuringiensis cotton on soil and microbial diversity by field experiments. In spite of this, in silico approach might be helpful to elucidate the impact of cry genes. The crystal a protein which was produced by Bt at the time of sporulation has been used as a biological pesticide to target the insectivorous pests like Cry1Ac for Helicoverpa armigera and Cry2Ab for Spodoptera sp. and Heliothis sp. Here, we present the comprehensive in silico analysis of Cry1Ac and Cry2Ab proteins with available in silico tools, databases and docking servers. Molecular docking of Cry1Ac with procarboxypeptidase from Helicoverpa armigera and Cry1Ac with Leucine aminopeptidase from Bos taurus has showed the 125(th) amino acid position to be the preference site of Cry1Ac protein. The structures were compared with each other and it showed 5% of similarity. The cross affinity of this toxin that have confirmed the earlier reports of ill effects of Bt cotton consumed by cattle.

  19. Effects of adult feeding on the reproduction and longevity of Noctuidae, Crambidae, Tortricidae and Elachistidae species

    Milano, Patricia; Berti Filho, Evoneo; Parra, Jose R. P.; Consoli, Fernando L.; Oda, Melissa L.

    2010-01-01

    This research evaluates the effect of the adult diet on the reproduction of Anticarsia gemmatalis Hubner, Heliothis virescens (Fabr.), Spodoptera frugiperda (J. E. Smith) (Noctuidae), Diatraea saccharalis (Fabr.) (Crambidae), Gymnandrosoma aurantianum Lima (Tortricidae) and Stenoma catenifer Walsingham (Elachistidae). Adults of all species were fed either water or a 10% honey solution. The egg viability for the 1 st and 2 n d egg masses, adult fecundity, longevity, number of mating and the ovigeny index (OI) (degree of ovarian maturation) were evaluated. Fecundity of A. gemmatalis and H. virescens was drastically reduced when females were fed only on water. Egg viability from both 1 st and 2 nd egg masses was variable between treatments. Females of A. gemmatalis, H. virescens and S. frugiperda, and males of some species had a reduced longevity when fed only on water. The number of matings was higher for A. gemmatalis and D. saccharalis when fed on water only. The OI was < 1.0 for all species evaluated indicating that all females may develop new oocytes as they age. Based on the OI and the reduced fecundity of A. gemmatalis and H. virescens, one observes that adult feeding is important for the reproduction of both species, and the IO is not a good parameter to indicate such condition. Spodoptera frugiperda, G. aurantianum, D. saccharalis and S. catenifer do not require any source of carbohydrates as adults to sustain their reproduction. (author)

  20. Effects of adult feeding on the reproduction and longevity of Noctuidae, Crambidae, Tortricidae and Elachistidae species; Efeito da alimentacao da fase adulta na reproducao e longevidade de especies de Noctuidae, Crambidae, Tortricidae e Elachistidae

    Milano, Patricia; Berti Filho, Evoneo; Parra, Jose R. P.; Consoli, Fernando L., E-mail: patmilano@gmail.co, E-mail: eberti@esalq.usp.b, E-mail: jrpparra@esalq.usp.b, E-mail: fconsoli@esalq.usp.b [Escola Superior de Agricultura Luiz de Queiroz. (ESALQ/USP), Piracicaba, SP (Brazil). Dept. de Entomologia e Acarologia; Oda, Melissa L., E-mail: melissa.oda@gmail.co [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil). Dept. de Ciencias Florestais

    2010-04-15

    This research evaluates the effect of the adult diet on the reproduction of Anticarsia gemmatalis Hubner, Heliothis virescens (Fabr.), Spodoptera frugiperda (J. E. Smith) (Noctuidae), Diatraea saccharalis (Fabr.) (Crambidae), Gymnandrosoma aurantianum Lima (Tortricidae) and Stenoma catenifer Walsingham (Elachistidae). Adults of all species were fed either water or a 10% honey solution. The egg viability for the 1{sup st} and 2{sup n}d egg masses, adult fecundity, longevity, number of mating and the ovigeny index (OI) (degree of ovarian maturation) were evaluated. Fecundity of A. gemmatalis and H. virescens was drastically reduced when females were fed only on water. Egg viability from both 1{sup st} and 2{sup nd} egg masses was variable between treatments. Females of A. gemmatalis, H. virescens and S. frugiperda, and males of some species had a reduced longevity when fed only on water. The number of matings was higher for A. gemmatalis and D. saccharalis when fed on water only. The OI was < 1.0 for all species evaluated indicating that all females may develop new oocytes as they age. Based on the OI and the reduced fecundity of A. gemmatalis and H. virescens, one observes that adult feeding is important for the reproduction of both species, and the IO is not a good parameter to indicate such condition. Spodoptera frugiperda, G. aurantianum, D. saccharalis and S. catenifer do not require any source of carbohydrates as adults to sustain their reproduction. (author)

  1. Chemical ecology of moths: Role of semiochemicals in host location by Ectomyelois ceratoniae and mate guarding by Heliothis virescens

    Hosseini, S.A.

    2017-01-01

    Semiochemical-based behavioral manipulation has been increasingly implemented in Integrated Pest Management (IPM) as an environmentally friendly strategy. For many pest species, however, efficient methods have yet to be developed. An efficient sex pheromone attractant is missing in management of the carob moth, Ectomyelois ceratoniae, a devastating fruit pest, because the major pheromone component is unstable. To explore the use of host-plant volatiles to attract carob moths, the pomegranate-...

  2. Chemical ecology of moths : Role of semiochemicals in host location by Ectomyelois ceratoniae and mate guarding by Heliothis virescens

    Hosseini, S.A.

    2017-01-01

    Semiochemical-based behavioral manipulation has been increasingly implemented in Integrated Pest Management (IPM) as an environmentally friendly strategy. For many pest species, however, efficient methods have yet to be developed. An efficient sex pheromone attractant is missing in management of the

  3. RNA-Seq Study of Microbially Induced Hemocyte Transcripts from Larval Heliothis virescens (Lepidoptera: Noctuidae

    Kent S. Shelby

    2012-08-01

    Full Text Available Larvae of the tobacco budworm are major polyphagous pests throughout the Americas. Development of effective microbial biopesticides for this and related noctuid pests has been stymied by the natural resistance mediated innate immune response. Hemocytes play an early and central role in activating and coordinating immune responses to entomopathogens. To approach this problem we completed RNA-seq expression profiling of hemocytes collected from larvae following an in vivo challenge with bacterial and fungal cell wall components to elicit an immune response. A de novo exome assembly was constructed by combination of sequence tags from all treatments. Sequence tags from each treatment were aligned separately with the assembly to measure expression. The resulting table of differential expression had > 22,000 assemblies each with a distinct combination of annotation and expression. Within these assemblies > 1,400 were upregulated and > 1,500 downregulated by immune activation with bacteria or fungi. Orthologs to innate immune components of other insects were identified including pattern recognition, signal transduction pathways, antimicrobial peptides and enzymes, melanization and coagulation. Additionally orthologs of components regulating hemocytic functions such as autophagy, apoptosis, phagocytosis and nodulation were identified. Associated cellular oxidative defenses and detoxification responses were identified providing a comprehensive snapshot of the early response to elicitation.

  4. The genetic architecture of a complex ecological trait: host plant use in the specialist moth, HELIOTHIS SUBFLEXA

    The study of the genetic basis of ecological adaptation remains in its infancy, and most studies have focused on phenotypically simple traits. Host plant use by herbivorous insects is phenotypically complex. While research has illuminated the evolutionary determinants of host use, knowledge of its...

  5. Impacts on transfer of the sperm of helicoverpa Armigera by irradiation (L. noctuidae)

    Liu Xiaohui; Li Yongjun; Wang Huasong; Song Jiaxiang

    2001-01-01

    Gamma irradiation did not influence the quantity of the eupyrene sperm bundles in duplex and that of the eupyrene sperm in spermatophore, but affected the maturing of eupyrene sperm bundles. When males were given sterilizing dose of 400 Gy, the quantity and the activity of the eupyrene sperm in the spermatheca were reduced significantly (P < 0.05)

  6. Feeding behaviour of helicoverpa armigera HBN (LEP. noctuidae) on tomatoes in greenhouse

    Saour, G.; Causse, R.

    1998-01-01

    The feeding behaviour of larvae of Helicoverpa arminegera was studied on tomato plants grown in a greenhouse using 32P -labelled caterpillars. When first larvae emerged from eggs deposited onto usual egg-laying sites, they fed on leaves, occasionally onto Inflorescence, and some burrowed into fruit when they reached the third instars. During the fourth and fifth instar, they fed alternately on leaves and fruit, and occasionally on stems. Toward the end of their development, the caterpillars went through a searching phase to look for a shelter for metamorphosis. This typical sequence could be altered and become more complex in relation with the emerging site of the caterpillars. Green fruits of tomato are usually damaged by larvae of at least 7-8 day old which made several entry holes. These entries were not usually followed by feeding, but they nevertheless damaged an average of 2 ± 0.75 fruits. (author). 13 refs., 4 figs

  7. Chlorophyll degradation in the gut of generalist and specialist Lepidopteran caterpillars.

    Badgaa, Amarsanaa; Jia, Aiqun; Ploss, Kerstin; Boland, Wilhelm

    2014-12-01

    Plant feeding herbivores excrete most of the ingested chlorophyll (Chl) as partly degraded derivatives lacking the phytol side chain and the central magnesium ion. An ecological role of digested and degraded Chls in the interactions between insects, their food plant and other insects has been described recently. To gain more information on common degradation patterns in plant-feeding insects, the orals secretions and frass of five Lepidopteran caterpillars covering generalists and specialists, namely Spodoptera littoralis, Spodoptera eridania, Heliothis virescens, Helicoverpa armigera, Manduca sexta, and, for comparison, of the leaf beetle larva Chrysomela lapponica were analyzed for chlorophyll catabolites. The major degradation products were determined as pheohorbide a/b and pyropheophorbide a/b by using LC-MS, LC-NMR, UV, and fluorescence spectrometry. The compounds were not present in fresh leaves of the food plants (Phaseolus lunatus, Nicotiana tabacum). The catabolite spectrum in generalists and specialists was qualitatively similar and could be attributed to the action of gut proteins and the strongly alkaline milieu in the digestive tract. Due to the anaerobic environment of the larval gut, the tetrapyrrole core of the Chl catabolites was not cleaved. Substantial amounts of Chl a/b metabolites were strongly complexed by a protein in the mid-gut.

  8. Utilisation of gamma radiation of Cobalt-60 as quarantine treatment of medicinal plant, aromatic and seasoning plants dehydrated infested by Lasioderma serricorne (Fabricius, 1792) (Coleoptera, Anobiidae) and Plodia interpunctella (Hubner, 1813) (Lepidoptera, Pyralidae)

    Alves, Juliana Nazare

    2007-01-01

    The research had as objective the use of the gamma radiation of the Cobalto-60 as quarantine treatment of the medicinal plant, aromatic and seasoning plants dehydrated infested by Lasioderma serricorne and Plodia interpunctella determining the disinfestation doses to attend the criterion in the not emergency of adults of the species in study and analysing through the Chromatography of Thin Layer the effect of the gamma radiation of the cobalto-60 on the active principle of extract dehydrated of Chamomilla recutita, Pimpinella anisum, Origanum vulgare, Cymbopogon citratus, Ocimum basilicum and Thymus vulgaris. The work was developed in the Laboratorio de Inseticidas in the Instituto Biologico in Sao Paulo in the period of August of 2005 the June of 2007. The radiation source used gamma was an experimental irradiator of Cobalto-60, model Gamacell 220, located in the Instituto de Pesquisas Energeticas e Nucleares - IPEN, located in Sao Paulo. In the period of 30 days after the irradiation of the samples evaluated the number of adults emerged of Lasioderma serricorne and Plodia interpunctella, using the data of mortality for the analysis of Probit. Obtained 100% of not emergency of adults in the Lasioderma serricorne with the dose of 2,00 kGy and 100% of not emergency of adults in the Plodia interpunctella with the dose of 2,25 kGy. The Chromatographic Analysis of Thin Layer was to evaluate did not show chemical differences in the extracts analysed. (author)

  9. Utilisation of gamma radiation of Cobalt-60 as quarantine treatment of medicinal plant, aromatic and seasoning plants dehydrated infested by Lasioderma serricorne (Fabricius, 1792) (Coleoptera, Anobiidae) and Plodia interpunctella (Hubner, 1813) (Lepidoptera, Pyralidae); Utilizacao da radiacao gama do Cobalto-60 como tratamento quarentenario de plantas medicinais, aromaticas e condimentares desidratadas infestadas por Lasioderma serricorne (Fabricius, 1792) (Coleoptera, Anobiidae) e Plodia interpunctella (Hubner, 1813) (Lepidoptera, Pyralidae)

    Alves, Juliana Nazare

    2007-07-01

    The research had as objective the use of the gamma radiation of the Cobalto-60 as quarantine treatment of the medicinal plant, aromatic and seasoning plants dehydrated infested by Lasioderma serricorne and Plodia interpunctella determining the disinfestation doses to attend the criterion in the not emergency of adults of the species in study and analysing through the Chromatography of Thin Layer the effect of the gamma radiation of the cobalto-60 on the active principle of extract dehydrated of Chamomilla recutita, Pimpinella anisum, Origanum vulgare, Cymbopogon citratus, Ocimum basilicum and Thymus vulgaris. The work was developed in the Laboratorio de Inseticidas in the Instituto Biologico in Sao Paulo in the period of August of 2005 the June of 2007. The radiation source used gamma was an experimental irradiator of Cobalto-60, model Gamacell 220, located in the Instituto de Pesquisas Energeticas e Nucleares - IPEN, located in Sao Paulo. In the period of 30 days after the irradiation of the samples evaluated the number of adults emerged of Lasioderma serricorne and Plodia interpunctella, using the data of mortality for the analysis of Probit. Obtained 100% of not emergency of adults in the Lasioderma serricorne with the dose of 2,00 kGy and 100% of not emergency of adults in the Plodia interpunctella with the dose of 2,25 kGy. The Chromatographic Analysis of Thin Layer was to evaluate did not show chemical differences in the extracts analysed. (author)

  10. Heribert KOZIOL's retirement party

    Patrice Loïez

    2001-01-01

    Photo 09: L. to r. : Simon van der Meer (inventor of 'Stochastic Cooling', Nobel prize 1984), Kurt Hubner, Director of Accelerators) Photo 11: L. to r.: Renzo Resegotti (builder of the ISR magnets), Simon van der Meer , Kurt Hubner Photo 17: Heribert Koziol (longtime PS-Divisions Beam Diagnostics Group Leader) Radio-Frequency Groups; former CLIC Study Leader),

  11. 77 FR 2539 - Pesticide Experimental Use Permit; Receipt of Application; Comment Request

    2012-01-18

    ...), tobacco budworm (Heliothis virescens), pink bollworm (Pectinophora gossypiella), fall armyworm (Spodoptera frugiperda), and beet armyworm (Spodoptera exigua). A copy of the application and any information submitted...

  12. Structure and transcription of the Helicoverpa armigera densovirus (HaDV2) genome and its expression strategy in LD652 cells.

    Xu, Pengjun; Graham, Robert I; Wilson, Kenneth; Wu, Kongming

    2017-02-07

    Densoviruses (DVs) are highly pathogenic to their hosts. However, we previously reported a mutualistic DV (HaDV2). Very little was known about the characteristics of this virus, so herein we undertook a series of experiments to explore the molecular biology of HaDV2 further. Phylogenetic analysis showed that HaDV2 was similar to members of the genus Iteradensovirus. However, compared to current members of the genus Iteradensovirus, the sequence identity of HaDV2 is less than 44% at the nucleotide-level, and lower than 36, 28 and 19% at the amino-acid-level of VP, NS1 and NS2 proteins, respectively. Moreover, NS1 and NS2 proteins from HaDV2 were smaller than those from other iteradensoviruses due to their shorter N-terminal sequences. Two transcripts of about 2.2 kb coding for the NS proteins and the VP proteins were identified by Northern Blot and RACE analysis. Using specific anti-NS1 and anti-NS2 antibodies, Western Blot analysis revealed a 78 kDa and a 48 kDa protein, respectively. Finally, the localization of both NS1 and NS2 proteins within the cell nucleus was determined by using Green Fluorescent Protein (GFP) labelling. The genome organization, terminal hairpin structure, transcription and expression strategies as well as the mutualistic relationship with its host, suggested that HaDV2 was a novel member of the genus Iteradensovirus within the subfamily Densovirinae.

  13. Effect of pyramiding Bt and CpTI genes on resistance of cotton to Helicoverpa armigera (Lepidoptera: Noctuidae) under laboratory and field conditions

    Cui, J.J.; Luo, J.Y.; Werf, van der W.; Ma, Y.; Xia, J.Y.

    2011-01-01

    Transgenic cotton (Gossypium hirsutum L.) varieties, adapted to China, have been bred that express two genes for resistance to insects. the Cry1Ac gene from Bacillus thuringiensis (Berliner) (Bt), and a trypsin inhibitor gene from cowpea (CpTI). Effectiveness of the double gene modification in

  14. Phylogenetic and functional characterization of ten P450 genes from the CYP6AE subfamily of Helicoverpa armigera involved in xenobiotic metabolism

    Shi, Yu; Wang, Huidong; Liu, Zhi

    2018-01-01

    450s in this subfamily can metabolise imidacloprid, but with lower efficiency than Bemisia tabaci CYP6CM1vQ. CYP6AE20 had virtually no metabolic competence to these four compounds but could metabolise several model fluorogenic substrates. These results showed the broad substrate spectrum of H...

  15. Preliminary Note on the Use of Radioisotopes to Study Some Cotton-Plant Pests in Africa; Note preliminaire sur l 'utilisation des radioisotopes dans l 'etude des parasites du cotonnier en afrique; Predvaritel'nye zamechaniya o primenenii radioizotopov dlya izucheniya nekotorykh vreditelej khlopchatnika v afrike.; Nota preliminar sobre el empleo de radioisotopos en el estudio de parasitos del algodonero en africa

    Delattre, R. [Institut de Recherches du Coton et Textiles, Paris (France)

    1963-09-15

    The larva of Diparopsis watersi Roth is harmful to the cotton-plant, destroying the flower and the boll. This noctuid, which is practically monophagous, passes the quiescent season either in the ground in the chrysalid-at-diapause form (from 10 November onwards) or in continuing generation (polyvoltine) on plants left standing. Laboratory studies have served to elucidate the main mechanisms initiating and terminating diapause. In the field, the rapid multiplication of the pest during the crop period is due both to univoltine individuals hatching out towards April-May and to non-diapause generations. The respective roles played by these two different sources need to be determined fairly accurately in order to decide which methods of control are appropriate: uprooting of the cotton-plant, destruction of the pupae at diapause in the ground, bringing the crop forward, etc. Radioisotope labelling of larvae coming to maturity at critical periods should make it possible to tackle this problem at the practical level. Preliminary experiments for determining simple labelling techniques have been carried out at Tikem (Republic of Chad). In a first trial, P{sup 32} in atomized solution was applied direct to the foliage of young cottonplants. Despite the effects of rain, absorption by the plant reached about 10% in a few hours. Radioactivity is not retained by various phyllophagous larvae (Sylepta derogata, Prodenia litura), but those feeding on the fruit-bearing parts of the plant (Heliothis armigera, Earias insulana, Diparopsis watersi, etc.) are easily detectable three months after the application. In a second trial, P{sup 32} and S{sup 35} were applied to old cotton-plants immediately before the natural time for Diparopsis to enter diapause. The overall findings give hope of being able to distinguish without too much difficulty, among chrysalid populations taken from the ground, those which fed on the cotton-plant before labelling, and hence which underwent a diapause. A

  16. Evaluation of two cotton varieties CRSP1 and CRSP2 for genetic transformation efficiency, expression of transgenes Cry1Ac + Cry2A, GT gene and insect mortality

    Arfan Ali

    2016-03-01

    Full Text Available Expression of the transgene with a desirable character in crop plant is the ultimate goal of transgenic research. Transformation of two Bt genes namely Cry1Ac and Cry2A cloned as separate cassette under 35S promoter in pKHG4 plant expression vector was done by using shoot apex cut method of Agrobacterium. Molecular confirmation of putative transgenic cotton plants for Cry1Ac, Cry2A and GT gene was done through PCR and ELISA. Transformation efficiency of CRSP-1 and CRSP-2 was calculated to be 1.2 and 0.8% for Cry1Ac while 0.9 and 0.6% for Cry2A and 1.5 and 0.7% for GTG respectively. CRSP-1 was found to adopt natural environment (acclimatized earlier than CRSP-2 when exposed to sunlight for one month. Expression of Cry1Ac, Cry2A and GTG was found to be 1.2, 1 and 1.3 ng/μl respectively for CRSP-1 as compared to CRSP-2 where expression was recorded to be 0.9, 0.5 and 0.9 ng/μl respectively. FISH analysis of the transgenic CRSP-1 and CRSP-2 demonstrated the presence of one and two copy numbers respectively. Similarly, the response of CRSP-1 against Glyphosate @1900 ml/acre was far better with almost negligible necrotic spot and efficient growth after spray as compared to CRSP-2 where some plants were found to have necrosis and negative control where the complete decay of plant was observed after seven days of spray assay. Similarly, almost 100% mortality of 2nd instar larvae of Heliothis armigera was recorded after three days in CRSP-1 as compared CRSP-2 where insect mortality was found to be less than 90%. Quantitatively speaking non transgenic plants were found with 23–90% leaf damage by insect, while CRSP-1 was with less than 5% and CRSP-2 with 17%. Taken together CRSP1 was found to have better insect control and weedicide resistance along with its natural ability of genetic modification and can be employed by the valuable farmers for better insect control and simultaneously for better production.

  17. Environmental Distribution and Diversity of Insecticidal Proteins of Bacillus thuringiensis Berliner

    Xavier, R.

    2007-01-01

    , however, the B. thuringiensis isolates BTRX-23 to BTRX-30 have two distinct protein profiles corresponding to 130 kDa and 68 kDa. These results show that there may be more than one B. thuringiensis strain that can infect Bombyx mori. The preliminary bioassay against second instar larvae of Heliothis armigera showed varying mortality rate. In conclusion, despite the ubiquitous presence of B. thuringiensis strains in different environments, specifically the sericulture environment supports B. thuringiensis in a significant manner compared to other environments. Further the ICPs produced by different strains of B. thuringiensis are unique in terms of the protein profile and hence may also differ in their insecticidal activities.

  18. Genomic innovations, transcriptional plasticity and gene loss underlying the evolution and divergence of two highly polyphagous and invasive Helicoverpa pest species

    Pearce, S L; Clarke, D F; East, P D

    2017-01-01

    BACKGROUND: Helicoverpa armigera and Helicoverpa zea are major caterpillar pests of Old and New World agriculture, respectively. Both, particularly H. armigera, are extremely polyphagous, and H. armigera has developed resistance to many insecticides. Here we use comparative genomics, transcriptom......BACKGROUND: Helicoverpa armigera and Helicoverpa zea are major caterpillar pests of Old and New World agriculture, respectively. Both, particularly H. armigera, are extremely polyphagous, and H. armigera has developed resistance to many insecticides. Here we use comparative genomics......, transcriptomics and resequencing to elucidate the genetic basis for their properties as pests. RESULTS: We find that, prior to their divergence about 1.5 Mya, the H. armigera/H. zea lineage had accumulated up to more than 100 more members of specific detoxification and digestion gene families and more than 100...... lacks certain genes and alleles conferring insecticide resistance found in H. armigera. Non-synonymous sites in the expanded gene families above are rapidly diverging, both between paralogues and between orthologues in the two species. Whole genome transcriptomic analyses of H. armigera larvae show...

  19. 40th Anniversary of the First Proton-Proton Collisions in the CERN Intersecting Storage Rings (ISR)

    CERN. Geneva

    2011-01-01

    Welcome, Luigi di Lella and Rolf HeuerDesign and Construction of the ISR, Kurt HubnerPhysics at small angles, Ugo Amaldi (TERA Foundation)The Impact of the ISR on Accelerator Physics and Technology, Philip J. BryantPhysics at high transverse momentum, Pierre Darriulat (VATLY-Hanoi)Concluding remarks, Rolf Heuer

  20. Ionizing radiation as a phytosanitary treatment against European corn borer (Lepidoptera: Crambidae) in ambient, low oxygen, and cold conditions

    The European corn borer, Ostrinia nubilalis (Hubner), (Lepidoptera: Crambidae), is a quarantine pest for several fresh commodities, including corn-on-the-cob, bell peppers, and green beans. Methyl bromide fumigation is the usual phytosanitary treatment, but the chemical is under increasing regulat...

  1. Laboratory scale production of the human recombinant iduronate 2 ...

    STORAGESEVER

    2009-05-04

    May 4, 2009 ... Pichia pastoris is yeast with the ability to use methanol as a sole source of carbon and ... methanol accumulation in the culture media (Cregg,. 1993). .... described by Hubner (1993); the incubation temperature of the reaction was ..... phenomenon also called degrading inactivation (Poutou et al., 2005b).

  2. Trunk Reservation in Multi-service Networks with BPP Traffic

    Zheng, H.; Zhang, Qi; Iversen, Villy Bæk

    2006-01-01

    In this paper we develop approximate models for trunk reservation in multi-service systems with BPP (Binomial-Poisson-Pascal) multi-rate traffic streams. The approximation is a generalization of previous work by Tran-Gia & Hubner who assumed Poisson arrival processes. It is based on a generalized...

  3. Introduced and Native Parasitoid Wasps Associated With Larch Casebearer (Lepidoptera: Coleophoridae) in Western Larch

    M. Miller-Pierce; D. C. Shaw; A. Demarco; P. T. Oester

    2015-01-01

    The larch casebearer [Coleophora laricella (Hubner)], a non-native insect, continues to impact western larch (Larix occidentalis Nutt.) through defoliation events in the Pacific Northwest. Biological control programs starting in the 1960s released seven species of parasitoid wasps to control C. laricella...

  4. Susceptibility and aversion of Spodoptera frugiperda to Cry1F Bt maize and considerations for insect resistance management

    Bacillus thuringiensis (Bt) maize was developed primarily for North American pests such as European corn borer (Ostrinia nubilalis Hubner). However, most Bt maize products also are cultivated outside of North America, where the primary pests are different and often have lower susceptibility to Bt to...

  5. Functional Hemispheric Asymmetries of Global/Local Processing Mirrored by the Steady-State Visual Evoked Potential

    Martens, Ulla; Hubner, Ronald

    2013-01-01

    While hemispheric differences in global/local processing have been reported by various studies, it is still under dispute at which processing stage they occur. Primarily, it was assumed that these asymmetries originate from an early perceptual stage. Instead, the content-level binding theory (Hubner & Volberg, 2005) suggests that the hemispheres…

  6. Characterisation of Bacillus thuringiensis kurstaki strains by toxicity ...

    , dipel, HD73, HD1dipel) were characterized by investigating their total plasmid profiling; cryIA genes profiling and toxicity towards local isolates of agricultural insects Helicoverpa armigera and Spodoptera litura. Result showed that LC50 for S.

  7. Transgenic Bacillus thuringiensis (Bt) chickpea: India's most wanted ...

    Sumita

    2013-09-25

    Sep 25, 2013 ... most wanted genetically modified (GM) pulse crop. Sumita Acharjee and Bidyut ... (predominantly, Helicoverpa armigera) and diseases, lack of supply of quality seeds, ... emerging from winter diapause. The trap crops are.

  8. Bioefficacy and mode-of-action of some limonoids of salannin group ...

    Unknown

    ... Nucleosil C-18 RP. The mobile phase was .... 100] and approximate digestibility (AD) as [(food ingested – .... Table 1. Effective concentrations (ppm) of various salannin type limonoids inhibiting growth (neonates) of H. armigera and S. litura.

  9. Reduced plant nutrition under elevated CO2 depresses the immunocompetence of cotton bollworm against its endoparasite

    Yin, Jin; Sun, Yucheng; Ge, Feng

    2014-01-01

    Estimating the immunocompetence of herbivore insects under elevated CO2 is an important step in understanding the effects of elevated CO2 on crop-herbivore-natural enemy interactions. Current study determined the effect of elevated CO2 on the immune response of Helicoverpa armigera against its parasitoid Microplitis mediator. H. armigera were reared in growth chambers with ambient or elevated CO2, and fed wheat grown in the concentration of CO2 corresponding to their treatment levels. Our res...

  10. Mr. Wolfgang Petritsch, Austrian Ambassador

    Patrice Loïez

    2002-01-01

    Dr.Peter Schmid/CERN/EP, Dr.Wolfgang Petritsch, Austrian Ambassador, Permanent representative at UN, Mrs.Nora Petritsch, Dr.Kurt Hubner/CERN/AC, Mrs. Frederike Klaus-Salesin, Adviser, Mrs.Andrea Strohmeier, Secretary of the Ambassador, Mr.Heinz Klaus, Attaché, Dr.Theodor Tortschanoff/CERN/LHC, Mr.Peter Storer, Advisor. Dr.Peter Schmid/CERN/EP, Dr.Wolfgang Petritsch, Austrian Ambassador, Permanent representative at UN, Mrs.Nora Petritsch, Dr.Kurt Hubner/CERN/AC, Mrs. Frederike Klaus-Salesin, Adviser, Mrs.Andrea Strohmeier, Secretary of the Ambassador, Mr.Heinz Klaus, Attaché, Dr.Theodor Tortschanoff/CERN/LHC, Mr.Peter Storer, Advisor.

  11. Breaking through the tranfer tunnel

    Laurent Guiraud

    2001-01-01

    This image shows the tunnel boring machine breaking through the transfer tunnel into the LHC tunnel. Proton beams will be transferred from the SPS pre-accelerator to the LHC at 450 GeV through two specially constructed transfer tunnels. From left to right: LHC Project Director, Lyn Evans; CERN Director-General (at the time), Luciano Maiani, and Director for Accelerators, Kurt Hubner.

  12. Formation of the U.S. Air Force Aviator Post Traumatic Stress Disorder Study Group

    2016-11-15

    Wood, III, John Heaton, Mark Hubner, Nicole Rhodes 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION... Questionnaire -9 PIQ performance intelligence quotient PTSD post-traumatic stress disorder RPA remotely piloted aircraft USAF U.S. Air Force VIQ verbal intelligence quotient ...Human Performance Wing U.S. Air Force School of Aerospace Medicine Aerospace Medicine Department 2510 Fifth St., Bldg. 840 Wright-Patterson AFB, OH

  13. Radiation induced F1 sterility in the management of lepidopterous pests: concept, overview and prospects

    Harwalkar, M.R.

    1994-01-01

    The phenomenon of F1 or inherited sterility has been observed in a number of important pests which include Heliothis virescens, H. Zea, Trichoplusia ni etc.. Key findings that have advanced in the development of radiation sterilization technique are reviewed. 2 refs

  14. Effects of 1,1-Dimethylpiperidinium Chloride on the Pests and Allelochemicals of Cotton and Pecan.

    P. A. Hedin; J. N. Jenkins; J. C. McCarty; J. E. Mulrooney; W. L. Parrott; A. Borazjani; C. H. Graves; T. H. Filer

    1984-01-01

    The growth regulator, PIX (mepiquat chloride - 1,1-dimethyl-piperdinium chloride), when applied to cotton (Gossypium hirsutum L.) and pecan (Carya illinoensis Koch), caused internode shortening. PIX did not elicit an increase in resistance in cotton to the tobacco budworm (Heliothis virescens (Fab.)], or in pecan...

  15. Characterization of Baculovirus Insecticides Expressing Tailored Bacillus thuringiensis CryIA(b) Crystal Proteins

    Martens, John W M; Knoester, Marga; Weijts, Franci; Groffen, Sander J A; Hu, Zhihong; Bosch, Dirk; Vlak, Just M.

    1995-01-01

    Full-length, truncated, and mature forms of the CryIA(b) insecticidal crystal protein gene of Bacillus thuringiensis were engineered into the p10 locus of Autographa californica nuclear polyhedrosis virus (AcNPV). A signal sequence of Heliothis virescens juvenile hormone esterase was introduced at

  16. Analysis of variation in virulence of Beauveria bassiana against insect pests of pigeonpea using qPCR.

    Senthilraja, Govindasamy; Anand, Theerthagiri; Mohankumar, Subbarayalu; Raguchander, Thiruvengadam; Samiyappan, Ramasamy

    2018-03-01

    Beauveria bassiana is a broad spectrum microbial bioagent used for the control of agriculturally important insect pests. However, in our experiments, two virulent isolates of B. bassiana (B2 and B10) showed specific preference toward Maruca vitrata and Helicoverpa armigera of pigeonpea. To better understand this feature, we developed a qPCR assay to quantify the chitinase (virulence factor) of B. bassiana during the infection process. Isolates of B. bassiana were grown on insect cuticle amended medium and minimal medium (without insect cuticle) to assess the induction of chitinase. Our results revealed a positive correlation between expression of chitinase by B. bassiana and the substrates (with or without cuticles of M. vitrata and H. armigera) used. This study showcases the methodology to quantify the chitinase and analysis of variation in virulence of B. bassiana (B2 and B10) against M. vitrata and H. armigera. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Mannose Phosphate Isomerase Isoenzymes in Plutella xylostella Support Common Genetic Bases of Resistance to Bacillus thuringiensis Toxins in Lepidopteran Species

    Herrero, Salvador; Ferré, Juan; Escriche, Baltasar

    2001-01-01

    A strong correlation between two mannose phosphate isomerase (MPI) isoenzymes and resistance to Cry1A toxins from Bacillus thuringiensis has been found in a Plutella xylostella population. MPI linkage to Cry1A resistance had previously been reported for a Heliothis virescens population. The fact that the two populations share similar biochemical, genetic, and cross-resistance profiles of resistance suggests the occurrence of homologous resistance loci in both species.

  18. Comparative studies of tripolyphosphate and glutaraldehyde cross-linked chitosan-botanical pesticide nanoparticles and their agricultural applications.

    Gabriel Paulraj, Michael; Ignacimuthu, Savarimuthu; Gandhi, Munusamy Rajiv; Shajahan, Azeez; Ganesan, Pathalam; Packiam, Soosaimanickam Maria; Al-Dhabi, Naif Abdhullah

    2017-11-01

    A nanopesticide formulation was developed using chitosan and a botanical pesticide PONNEEM ® and its antifeedant, larvicidal and growth regulating activities were screened against Helicoverpa armigera, a major lepidopteran pest. Chitosan nanoparticles (CSNs) were prepared by using two different cross-linking agents namely glutaraldehyde (GLA) and tripolyphosphate (TPP). The effects of cross linking agents on CSNs and the biological properties against the insect pest were also studied. Cross linking of chitosan with either TPP or GLA was confirmed through Fourier Transform Infrared (FTIR) spectroscopy. Electron micrograph revealed that the size of CSNs varied from 32 to 90nm. The stability of nanoparticles lasted for 9days in CSNs-TPP-PONNEEM. In CSNs-GLA-PONNEEM, the stability of nanoparticles was higher. CSNs-TPP-PONNEEM treatment recorded 88.5% antifeedant activity and 90.2% larvicidal activity against H. armigera. Weights of H. armigera pupae in CSNs-TPP-PONNEEM treatment were significantly low. Chitosan-based nano-pesticide formulation holds great promise in H. armigera management. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. African Journal of Biotechnology - Vol 11, No 30 (2012)

    Propagation physiology of Juniperus phoenicea L. from Jordan using seeds and in vitro culture techniques: Baseline information for a conservation perspective ... Morphological and chemical characteristics of tomato foliage as mechanisms of resistance to Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) larvae ...

  20. DNA synthesis in the imaginal wing discs of the American bollworm ...

    Unknown

    The effect of two insect growth regulators of plant origin viz. plumbagin and azadirachtin and the ecdysteroids. 20-hydroxyecdysone, makisterone A and a phytoecdysteroid on DNA synthesis in imaginal wing discs of day 4 final instar Helicoverpa armigera larvae was studied. DNA synthesis increased with increase in time of.

  1. Effects of temperature and nonionizing ultraviolet radiation treatments of eggs of five host insects on production of Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) for biological control applications.

    Trichogramma are used worldwide as biological control against insect pests, attacking eggs of over 200 species. Eggs of Spodoptera litura, Corcyra cephalonica, Plutella xylostella and Helicoverpa armigera were tested to consider the effect of temperature and radiation on parasitization, emergence of...

  2. First occurrence of Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae) preying on defoliating caterpillars of oil palm in the state of Para, Brazil

    Ribeiro, Rafael C.; Lemos, Walkymario P.; Muller, Antonio A.

    2010-01-01

    The oil palm Elaeis guineensis is usually attacked by pests, particularly, defoliating caterpillars. Between 2004 and 2006 a stinkbug predator (Asopinae) was registered preying on caterpillars of Brassolis sophorae L., Opsiphanes invirae Hubner (Lepidoptera: Nymphalidae) and Sibine spp. (Lepidoptera: Limacodidae), reducing their populations in commercial oil palm plantations in the State of Para, Brazil. Specimens of the natural enemy were collected, mounted, and identified as Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae), corresponding to the first report of the occurrence of this stinkbug attacking defoliating caterpillars of oil palm in Brazil. (author)

  3. First occurrence of Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae) preying on defoliating caterpillars of oil palm in the state of Para, Brazil; Primeira ocorrencia de Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae) predando lagartas desfolhadoras do dendezeiro no estado do Para, Brasil

    Ribeiro, Rafael C.; Lemos, Walkymario P.; Muller, Antonio A. [EMBRAPA Amazonia Oriental, Belem, PA (Brazil). Lab. de Entomologia], e-mail: rafaufra@yahoo.com.br, e-mail: wplemos@cpatu.embrapa.br; Muller, Antonio A. [Embrapa Amazonia Oriental, Belem, PA (Brazil). Lab. de Entomologia; Bernardino, Aline S.; Buecke, Joel [Grupo Agropalma S/A., Tailandia, PA (Brazil)

    2010-01-15

    The oil palm Elaeis guineensis is usually attacked by pests, particularly, defoliating caterpillars. Between 2004 and 2006 a stinkbug predator (Asopinae) was registered preying on caterpillars of Brassolis sophorae L., Opsiphanes invirae Hubner (Lepidoptera: Nymphalidae) and Sibine spp. (Lepidoptera: Limacodidae), reducing their populations in commercial oil palm plantations in the State of Para, Brazil. Specimens of the natural enemy were collected, mounted, and identified as Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae), corresponding to the first report of the occurrence of this stinkbug attacking defoliating caterpillars of oil palm in Brazil. (author)

  4. Biocontrol Potential of Steinernema thermophilum and Its Symbiont Xenorhabdus indica Against Lepidopteran Pests: Virulence to Egg and Larval Stages.

    Kalia, Vinay; Sharma, Garima; Shapiro-Ilan, David I; Ganguly, Sudershan

    2014-03-01

    Under laboratory conditions, the biocontrol potential of Steinernema thermophilum was tested against eggs and larval stages of two important lepidopteran insect pests, Helicoverpa armigera and Spodoptera litura (polyphagous pests), as well as Galleria mellonella (used as a model host). In terms of host susceptibility of lepidopteran larvae to S. thermophilum, based on the LC50 36 hr after treatment, G. mellonella (LC50 = 16.28 IJ/larva) was found to be more susceptible than S. litura (LC50 = 85 IJ/larva), whereas neither host was found to be significantly different from H. armigera (LC50 = 54.68 IJ/larva). In addition to virulence to the larval stages, ovicidal activity up to 84% was observed at 200 IJ/50 and 100 eggs of H. armigera and S. litura, respectively. To our knowledge this is the first report of entomopathogenic nematode pathogenicity to lepidopteran eggs. Production of infective juvenile (IJ) nematodes/insect larva was also measured and found to be positively correlated with rate of IJ for H. armigera (r = 0.990), S. litura (r = 0.892), as well as G. mellonella (r = 0.834). Both Phase I and Phase II of symbiotic bacteria Xenorhabdus indica were tested separately against neonates of H. armigera and S. litura by feeding assays and found to be virulent to the target pests; phase variation did not affect the level of virulence. Thus S. thermophilum as well as the nematode's symbiotic bacteria applied separately have the potential to be developed as biocontrol agents for key lepidopteran pests.

  5. History and Current Status of Development and Use of Viral Insecticides in China

    Xiulian Sun

    2015-01-01

    Full Text Available The use of insect viruses as biological control agents started in the early 1960s in China. To date, more than 32 viruses have been used to control insect pests in agriculture, forestry, pastures, and domestic gardens in China. In 2014, 57 products from 11 viruses were authorized as commercial viral insecticides by the Ministry of Agriculture of China. Approximately 1600 tons of viral insecticidal formulations have been produced annually in recent years, accounting for about 0.2% of the total insecticide output of China. The development and use of Helicoverpa armigera nucleopolyhedrovirus, Mamestra brassicae nucleopolyhedrovirus, Spodoptera litura nucleopolyhedrovirus, and Periplaneta fuliginosa densovirus are discussed as case studies. Additionally, some baculoviruses have been genetically modified to improve their killing rate, infectivity, and ultraviolet resistance. In this context, the biosafety assessment of a genetically modified Helicoverpa armigera nucleopolyhedrovirus is discussed.

  6. 2678-IJBCS-Article-Abla Dela Mondedji

    hp

    l'envahissement de la flore forestière togolaise par les espèces végétales exotiques : cas du neem (Azadirachta indica). Mémoire de D.E.A., Université de Lomé, 61p. Kranthi KR, Jadhav D, Wanjari R, Kranrhi S,. Russel D. 2001. Pyrethroid resistance and mechanisms of resistance in field strains of Helicoverpa armigera.

  7. Transmission of Different Nucleopolyhedroviruses by Two Ectoparasitoids – Bracon hebetor Say (Hymenoptera: Braconidae) and Euplectrus plathypenae (Howard) (Hymenoptera: Eulophidae)

    Emanouela E. Stoianova; Nikolay A. Balevski

    2010-01-01

    The transmission of nucleopolyhedroviruses (NPVs) of Autographa gamma (AgNPV), Mamestra brassicae (MbNPV), Lacanobia oleraceae (LoNPV), Helicoverpa armigera (HaNPV) and Xantia c-nigrum (XnNPV) to their relevant larvae by the ectoparasitoid Bracon hebetor and the transmission of the multiple-enveloped NPVs of Spodoptera exigua (SeMNPV) and Spodoptera frugiperda (SfMNPV) by the ectoparasitoid Euplectrus plathypenae was examined. Two methods of contamination of the both parasitoids (exposure to ...

  8. Chlorantraniliprole as a candidate pesticide used in combination with the attracticides for lepidopteran moths.

    Liu, Yongqiang; Gao, Yu; Liang, Gemei; Lu, Yanhui

    2017-01-01

    Methomyl is currently used as a toxicant for the attracticide BioAttract in cotton and vegetables in China. However, methomyl is highly toxic to non-target organisms and a more environmental friendly acceptable alternative is required. Larvae of three lepidopteran insects Helicoverpa armigera, Agrotis ipsilon and Spodoptera litura are important pests of these crops in China. In the present study, the toxicity of 23 commonly used insecticides were tested on H. armigera, then tested the susceptibility of A. ipsilon and S. litura moths to the insecticides which were the most toxic to H. armigera, and the acute toxicity of the most efficacious insecticides were further investigated under laboratory conditions. Chlorantraniliprole, emamectin benzoate, spinetoram, spinosad and methomyl exhibited high levels of toxicity to H. armigera moths with a mortality of 86.67%, 91.11%, 73.33%, 57.78% and 80.00%, respectively, during 24 h period at the concentration of 1 mg a.i. L-1. Among these five insecticides, A. ipsilon and S. litura moths were more sensitive to chlorantraniliprole, emamectin benzoate and methomyl. The lethal time (LT50) values of chlorantraniliprole and methomyl were shorter than emamectin benzoate for all three lepidopteran moth species at 1000 mg a.i. L-1 compared to concentrations of 500, 100 and 1 mg a.i L-1. Chlorantraniliprole was found to have similar levels of toxicity and lethal time on the three lepidopteran moths tested to the standard methomyl, and therefore, can be used as an alternative insecticide to methomyl in the attracticide for controlling these pest species.

  9. Des pratiques culturales influent sur les attaques de deux ravageurs ...

    La culture de tomate est attaquée par plusieurs ravageurs dont Helicoverpa armigera et Tuta absoluta. Dans le but d'évaluer l'effet des pratiques culturales de la tomate sur ces principaux ravageurs dans les Niayes (Sénégal), un échantillonnage de 98 parcelles est effectué, sur quatre cycles de culture en saison sèche, de ...

  10. Baseline sensitivity of maize borers in India to the Bacillus thuringiensis insecticidal proteins Cry1A.105 and Cry2Ab2.

    Jalali, Sushil K; Yadavalli, Lalitha; Ojha, Rakshit; Kumar, Pradyumn; Sulaikhabeevi, Suby B; Sharma, Reema; Nair, Rupa; Kadanur, Ravi C; Kamath, Subray P; Komarlingam, Mohan S

    2015-08-01

    Among the major pests of maize in India are two stem borers, Chilo partellus (Swinhoe) and Sesamia inferens (Walker), and an earworm, Helicoverpa armigera (Hübner). As a pest control strategy, transgenic Bacillus thuringiensis (Bt) maize hybrids are undergoing regulatory trials in India. We have determined the sensitivity of the target lepidopterans to the insecticidal Bt proteins expressed in Bt maize, as this determines product efficacy and the resistance management strategy to be adopted. Maize hybrids with event MON89034 express two insecticidal Bt proteins, Cry1A.105 and Cry2Ab2. Sensitivity profiles of 53 populations of C. partellus, 21 populations of S. inferens and 21 populations of H. armigera, collected between 2008 and 2013 from maize-growing areas in India, to Cry1A.105 and Cry2Ab2 proteins were generated through dose-response assays. Cry1A.105 protein was the most effective to neonates of C. partellus (mean MIC90 range 0.30-1.0 µg mL(-1) ) and H. armigera (mean MIC90 range 0.71-8.22 µg mL(-1) ), whereas Cry2Ab2 (mean MIC90 range 0.65-1.70 µg mL(-1) ) was the most effective to S. inferens. Populations of C. partellus, S. inferens and H. armigera were susceptible to the Bt proteins Cry1A.105 and Cry2Ab2. The Bt sensitivity data will serve as precommercialisation benchmarks for resistance monitoring purposes. © 2014 Society of Chemical Industry.

  11. Developing a neem-based pest management product: laboratory evaluations of neem extracts on insect pests resistance to synthetic pesticides

    Ahmad, I.; Permana, A.D.; Rahadian, R.; Wibowo, S.A

    1998-12-16

    Laboratory studies has been conducted as a part of a project aimed at the development of a neem-based insecticide for pest management purposes. Permethrin, a pyrethroid insecticide, and neem (Azadirachta indica) products were tested against larvae of Diamondback Moth Plutella xylostella, and Helicoverpa armigera collected from several locations in West Java, Indonesia. The results of bioassay showed that the average LC{sub 50} values of permethrin for Plutella xylostella had been 60-100 fold higher as compared with the normal dosage recommended. Similarly, the LC{sub 50} values obtained for Helicoverpa armigera had been 46-73 fold as compared with the recommended dosage. These facts suggest that both insects have developed resistance to permethrin. The results of bioassay with neem-products tested against Plutella xylostella and Helicoverpa armigera larvae showed that statistically LC{sub 50} values of neem-products for each strain of either Plutella xylostella or Helicoverpa armigera were not significantly different one to another. We also found that neem-treated insects, even though they were not killed directly by the insecticide, were not able to molt to the next instar or pupae, so that very low percentage of adults emerged. The susceptibility of neem-products could not be easily determined by only measuring the LC{sub 50} values from the larval stage, but the disruption of the growth and development of the insect should be considered as well. Our findings suggest that neem-products could be used effectively to control insects which have developed resistance to conventional insecticide. (author)

  12. EVALUATION OF FOUR INTEGRATED PEST MANAGEMENT PACKAGES FOR CONTROLLING MAIN PESTS OF COTTON IN RAINFED FIELDS

    Nurindah Nurindah; Dwi Adi Sunarto

    2014-01-01

    Cotton production nationally is low due to various constraints, including pests. Two main pests commonly found in cotton plantation in rain fed fields are cotton leafhopper (Amrasca biguttula) and cotton bollworm (Helicoverpa armigera). The study aimed to evaluate four packages of integrated pest management (IPM) techniques to control cotton leafhopper and cotton bollworm in rain fed fields. The experiment was conducted in farmers’ fields at Asembagus, East Java, between January and July 2012...

  13. Insect Resistance to Bacillus thuringiensis Toxin Cry2Ab Is Conferred by Mutations in an ABC Transporter Subfamily A Protein.

    Wee Tek Tay

    2015-11-01

    Full Text Available The use of conventional chemical insecticides and bacterial toxins to control lepidopteran pests of global agriculture has imposed significant selection pressure leading to the rapid evolution of insecticide resistance. Transgenic crops (e.g., cotton expressing the Bt Cry toxins are now used world wide to control these pests, including the highly polyphagous and invasive cotton bollworm Helicoverpa armigera. Since 2004, the Cry2Ab toxin has become widely used for controlling H. armigera, often used in combination with Cry1Ac to delay resistance evolution. Isolation of H. armigera and H. punctigera individuals heterozygous for Cry2Ab resistance in 2002 and 2004, respectively, allowed aspects of Cry2Ab resistance (level, fitness costs, genetic dominance, complementation tests to be characterised in both species. However, the gene identity and genetic changes conferring this resistance were unknown, as was the detailed Cry2Ab mode of action. No cross-resistance to Cry1Ac was observed in mutant lines. Biphasic linkage analysis of a Cry2Ab-resistant H. armigera family followed by exon-primed intron-crossing (EPIC marker mapping and candidate gene sequencing identified three independent resistance-associated INDEL mutations in an ATP-Binding Cassette (ABC transporter gene we named HaABCA2. A deletion mutation was also identified in the H. punctigera homolog from the resistant line. All mutations truncate the ABCA2 protein. Isolation of further Cry2Ab resistance alleles in the same gene from field H. armigera populations indicates unequal resistance allele frequencies and the potential for Bt resistance evolution. Identification of the gene involved in resistance as an ABC transporter of the A subfamily adds to the body of evidence on the crucial role this gene family plays in the mode of action of the Bt Cry toxins. The structural differences between the ABCA2, and that of the C subfamily required for Cry1Ac toxicity, indicate differences in the

  14. Lethality of gamma radiation and malathion to the indian meal moth, plodia interpunctella

    Eesa, N.M.; Moursy, L.E.

    1991-01-01

    The lethality of gamma radiation and the organo phosphorous insecticide, malathion, as well as the combined action of both was determined for the five larval instars of the indian meal moth, plodia interpunctella (Hubner). The younger instars were more susceptible to both gamma radiation and malathion. The L D 50 values of gamma radiation increased gradually with the instar. Malathion was highly toxic to the first four instars, but the fifth instar required a much larger dose. Gamma radiation combined with malathion at the L D 25 values was antagonistic when evaluated against each of the five larval instars of the indian meal moth. Thus, the use of gamma radiation with malathion does not seem to be a promising control strategy. However, further research investigations are needed to confirm this finding.3 tab

  15. Studies on controls of the insects infested on growing legume crops and stored grains

    Chung, K.H.; Kwon, S.H.; Lee, Y.I.; Shin, I.C.; Koh, Y.S.

    1980-01-01

    Present studies were carried out to control the insect pests which infest on rice, barley, wheat, redbeam and mungbeam grains during the storage period. For application of radiation to the pest controls, life spans of indian-meal moth (Plodia interpuctella Hubner) and bean weevil (Callosobruches chinensis L.) were investigated in different rearing conditions. Eggs and adults of the bean weevil were irradiated with various doses of γ-ray to determine radiosensitivities of the insect. For the ecological control of general legume insects, screening for varietal resistance to bean weevil and beanfly were performed in the experiment field. Radioisotope, P-32, was applied to screening of soybean resistant to aphid. Also, the germinability and the seedling height were measured in γ-ray irradiated mungbean for the grain storage. (author)

  16. LHC availability and performance in 2011

    Macpherson, A.L.

    2012-01-01

    In 2011, the LHC had an excellent year, with delivered luminosity for proton-proton running at 3.5 TeV per beam well in excess of the target of 1 fb -1 set prior to the 2011 run. Indeed, with both record totals for delivered luminosities in both proton-proton and lead-lead running, several special optics runs and a vigorous machine development program, 2011 exceeded all expectations in terms of machine performance. Stable beam availability of about 32 %, which corresponds to a Hubner factor of 0.22 and 0.24 for proton and Ions runs respectively. While fault tracking was not fully complete, successful mitigations against downtime due to radiation induced single event upsets, have already been observed, and further improvements are expected in 2012. This should help reduce the number of non-programmed beam dumps in 2012

  17. Impact of the Stem Extract of on the Feeding Potential and Histological Architecture of the Midgut Epithelial Tissue of Early Fourth Instars of HÜbner

    Monika Mishra

    2015-01-01

    Full Text Available Helicoverpa armigera HÜbner is one of the most important agricultural crop pests in the world causing heavy crop yield losses. The continued and indiscriminate use of synthetic insecticides in agriculture for their control has received wide public apprehension because of multifarious problems, including insecticide resistance, resurgence of pest species, environmental pollution, and toxic hazards to humans and nontarget organisms. These problems have necessitated the need to explore and develop alternative strategies using eco-friendly and biodegradable plant products. In view of this, the efficacy of Thevetia neriifolia methanol stem extract was evaluated against the early fourth instars of H. armigera as an antifeedant and stomach poison agent. Feeding of larvae with the diet containing 0.005%–5.0% extract resulted in 2.06%–37.35% antifeedant index; the diet with 5.0% extract caused 54.3% reduced consumption. The negative impact of extract on larval feeding resulted in 37.5%–77.7% starvation, causing adverse effects on the larval weight. Choice between control and experimental diet resulted in feeding preference of larvae for the control diet, leading to 7.3%–42.9% reduced consumption of extract-containing diet. The only exception was the diet with 0.005% extract, which could not cause any deterrence. The midgut histological architecture of H. armigera larvae fed with 0.005%–0.05% extract-containing diet with negligible antifeedant potential showed significant damage, shrinkage, and distortion and vacuolization of gut tissues and peritrophic membrane, causing the disintegration of epithelial, goblet, and regenerative cells; the damage increased with the increase in concentration. These changes in the gut caused negative impact on the digestion and absorption of food and thus nutritional deficiency in the larvae, which could probably affect their growth and development. This study reveal the appreciable stomach poison potential of T

  18. PRODUCT NEEM AZAL T/S - BROAD-SPECTRUM PHYPOPESTICIDE FOR CONTROL OF PESTS ON VEGETABLE CROPS

    Vinelina Yankova

    2016-09-01

    Full Text Available Experiments for determination of the effectiveness of product Neem Azal T/S (a. i. azadirachtin were conducted at a concentration of 0,3% against some major pests in vegetable crops grown in greenhouses at the Maritsa Vegetable Crops research Institute, Plovdiv during the period 2010-2016. It was established very good insecticidal and acaricidal action of phytopesticide against: cotton aphid (Aphis gossypii Glov.; green peach aphid (Myzus persicae Sulz.; western flower trips (Frankliniella occidentalis Perg.; cotton bollworm (Helicoverpa armigera Hubn.; tomato borer (Tuta absoluta Meyrick and two-spotted spider mite (Tetranichus urticae Koch.. This product is a successful alternative to using chemical insecticides and acaricides.

  19. A multisensory centrifugal neuron in the olfactory pathway of heliothine moths

    Zhao, Xin-Cheng; Pfuhl, Gerit; Surlykke, Annemarie

    2013-01-01

    fine processes in the dorsomedial region of the protocerebrum and extensive neuronal branches with blebby terminals in all glomeruli of the antennal lobe. Its soma is located dorsally of the central body close to the brain midline. Mass-fills of antennal-lobe connections with protocerebral regions...... showed that the centrifugal neuron is, in each brain hemisphere, one within a small group of neurons having their somata clustered. In both species the neuron was excited during application of non-odorant airborne signals, including transient sound pulses of broad bandwidth and air velocity changes....... Additional responses to odors were recorded from the neuron in Heliothis virescens. The putative biological significance of the centrifugal antennal-lobe neuron is discussed with regard to its morphological and physiological properties. In particular, a possible role in multisensory processes underlying...

  20. Isolation of BAC Clones Containing Conserved Genes from Libraries of Three Distantly Related Moths: A Useful Resource for Comparative Genomics of Lepidoptera

    Yuji Yasukochi

    2011-01-01

    Full Text Available Lepidoptera, butterflies and moths, is the second largest animal order and includes numerous agricultural pests. To facilitate comparative genomics in Lepidoptera, we isolated BAC clones containing conserved and putative single-copy genes from libraries of three pests, Heliothis virescens, Ostrinia nubilalis, and Plutella xylostella, harboring the haploid chromosome number, =31, which are not closely related with each other or with the silkworm, Bombyx mori, (=28, the sequenced model lepidopteran. A total of 108–184 clones representing 101–182 conserved genes were isolated for each species. For 79 genes, clones were isolated from more than two species, which will be useful as common markers for analysis using fluorescence in situ hybridization (FISH, as well as for comparison of genome sequence among multiple species. The PCR-based clone isolation method presented here is applicable to species which lack a sequenced genome but have a significant collection of cDNA or EST sequences.

  1. Las especies de Trichogramma de Uruguay (Hymenoptera: Trichogrammatidae Trichogramma species from Uruguay (Hymenoptera: Trichogrammatidae

    César Basso

    2004-07-01

    Full Text Available Fueron recolectadas cinco especies de Trichogramma Westwood en Uruguay. La más ampliamente distribuida T. pretiosum Riley parasita Diatraea saccharalis (Fabricius, Heliothis zea (Boddie, Alabama argillacea (Hübner y Argyrotaenia sphaleropa (Meyrick. Trichogramma exiguum Pinto & Platner, a menudo confundida con T. fuentesi Torre, parasitan Bonagota cranaodes (Meyrick y A. sphaleropa. Otras dos especies T. galloi Zucchi y T. distinctum Zucchi parasita D. saccharalis. Ellas presentan una morfología relativamente similar y, de acuerdo a la información disponible, no es posible decidir si son especies próximas o sinónimas. Finalmente, T. bellaunionense Basso & Pintureau fue recolectada en Uruguay hasta el momento sólo sobre D. saccharalis. Se provee una clave ilustrada para determinar esas cinco especies. Por otra parte, se incluye una revisión del uso actual y proyectado de Trichogramma para controlar diferentes plagas en diversos cultivos en este país.Five Trichogramma Westwood species were collected in Uruguay. The widely distributed T. pretiosum Riley parasitizes Diatraea saccharalis (Fabricius, Heliothis zea (Boddie, Alabama argillacea (Hübner and Argyrotaenia sphaleropa (Meyrick. Trichogramma exiguum Pinto & Platner, often confused with T. fuentesi Torre, parasitizes Bonagota cranaodes (Meyrick and A. sphaleropa. The two species T. galloi Zucchi and T. distinctum Zucchi parasitize D. saccharalis. Their morphology is relatively close and, from the information available, it is not possible to decide if they are closely related species or synonymous species. Finally, up to now, T. bellaunionense Basso & Pintureau was only collected from Uruguay on D. saccharalis. An illustrated key is provided to identify these five species. Moreover, the present and expected use of Trichogramma to control different pests in different Uruguayan crops is reviewed.

  2. The basic principles of the application of sterile insect technique for area-wide insect pest control

    Singgih Sutrisno

    2006-01-01

    Sterile Insect Technique (SIT) is a new insect pest control technique, potential, and compatible to other techniques. This technique includes irradiation of insect colony in the laboratory using gamma, n, or x-rays and then release them in the field periodically to obtain the increase of sterility probability level from the first generation to the dependence as the result the decrease of the fertility level in the field. The effect the release of sterile insects ( 9:1 ratio to the male indigenous and reproductive potential every single female of each generation reproduce 5 females ) to the insect reduction population model is conceptually discussed. From one million of the female parental decrease to be 26, 316; 1,907; 10; and 0 insects at the first, second, third, and the forth progeny respectively. Then if sterile insect technique integrated with chemical technique (insecticide) 90% kill, it will be much more effective compared to the application sterile insect technique only. From the number of one million population of insects will decrease to be 2,632; 189; and 0 insects at the first, second, and the third progeny respectively. In the Lepidoptera insects was found a phenomenon of inherited sterility. According to Knipling (1970) the inherited sterility in the first offspring caused by chromosome translocation in the gamete . In the individual of heterozygote will be die and in the homozygotes is still alive. Interspecific hybrid sterility first time was found by Laster (1972) from a cross between males Heliothis virescens (F) and females Heliothis subflexa Guenee. Male moths of the first offspring from the cross between H. virescens and H. subflexa is sterile and the females still remain fertile. If the female moths of the first offspring back crossed with male H. virescens the phenomenon of sterility always found will same situation as mention earlier the male offspring is sterile and the females is fertile ( the male F2 will be sterile and the females will

  3. Feeding behaviour of generalist pests on Brassica juncea: implication for manipulation of glucosinolate biosynthesis pathway for enhanced resistance.

    Kumar, Pawan; Augustine, Rehna; Singh, Amarjeet Kumar; Bisht, Naveen C

    2017-10-01

    Differential accumulation of plant defence metabolites has been suggested to have important ecological consequence in the context of plant-insect interactions. Feeding of generalist pests on Brassica juncea showed a distinct pattern with selective exclusion of leaf margins which are high in glucosinolates. Molecular basis of this differential accumulation of glucosinolates could be explained based on differential expression profile of BjuMYB28 homologues, the major biosynthetic regulators of aliphatic glucosinolates, as evident from quantitative real-time PCR and promoter:GUS fusion studies in allotetraploid B. juncea. Constitutive overexpression of selected BjuMYB28 homologues enhanced accumulation of aliphatic glucosinolates in B. juncea. Performance of two generalist pests, Helicoverpa armigera and Spodoptera litura larvae, on transgenic B. juncea plants were poor compared to wild-type plants in a no-choice experiment. Correlation coefficient analysis suggested that weight gain of H. armigera larvae was negatively correlated with gluconapin (GNA) and glucobrassicanapin (GBN), whereas that of S. litura larvae was negatively correlated with GNA, GBN and sinigrin (SIN). Our study explains the significance and possible molecular basis of differential distribution of glucosinolates in B. juncea leaves and shows the potential of overexpressing BjuMYB28 for enhanced resistance of Brassica crops against the tested generalist pests. © 2017 John Wiley & Sons Ltd.

  4. In-silico determination of insecticidal potential of Vip3Aa-Cry1Ac fusion protein against Lepidopteran targets using molecular docking

    Aftab eAhmad

    2015-12-01

    Full Text Available Study and research of Bt (Bacillus thuringiensis transgenic plants have opened new ways to combat insect pests. Over the decades, however, insect pests, especially the Lepidopteran, have developed tolerance against Bt delta-endotoxins. Such issues can be addressed through the development of novel toxins with greater toxicity and affinity against a broad range of insect receptors. In this computational study, functional domains of Bacillus thuringiensis crystal delta-endotoxin (Cry1Ac insecticidal protein and vegetative insecticidal protein (Vip3Aa have been fused to develop a broad-range Vip3Aa-Cry1Ac fusion protein. Cry1Ac and Vip3Aa are non-homologous insecticidal proteins possessing receptors against different targets within the midgut of insects. The insecticidal proteins were fused to broaden the insecticidal activity. Molecular docking analysis of the fusion protein against aminopeptidase-N (APN and cadherin receptors of five Lepidopteran insects (Agrotis ipsilon, Helicoverpa armigera, Pectinophora gossypiella, Spodoptera exigua and Spodoptera litura revealed that the Ser290, Ser293, Leu337, Thr340 and Arg437 residues of the fusion protein are involved in the interaction with insect receptors. The Helicoverpa armigera cadherin receptor, however, showed no interaction, which might be due to either loss or burial of interactive residues inside the fusion protein. These findings revealed that the Vip3Aa-Cry1Ac fusion protein has a strong affinity against Lepidopteran insect receptors and hence has a potential to be an efficient broad-range insecticidal protein.

  5. Ignoring the irrelevant: auditory tolerance of audible but innocuous sounds in the bat-detecting ears of moths

    Fullard, James H.; Ratcliffe, John M.; Jacobs, David S.

    2008-03-01

    Noctuid moths listen for the echolocation calls of hunting bats and respond to these predator cues with evasive flight. The African bollworm moth, Helicoverpa armigera, feeds at flowers near intensely singing cicadas, Platypleura capensis, yet does not avoid them. We determined that the moth can hear the cicada by observing that both of its auditory receptors (A1 and A2 cells) respond to the cicada’s song. The firing response of the A1 cell rapidly adapts to the song and develops spike periods in less than a second that are in excess of those reported to elicit avoidance flight to bats in earlier studies. The possibility also exists that for at least part of the day, sensory input in the form of olfaction or vision overrides the moth’s auditory responses. While auditory tolerance appears to allow H. armigera to exploit a food resource in close proximity to acoustic interference, it may render their hearing defence ineffective and make them vulnerable to predation by bats during the evening when cicadas continue to sing. Our study describes the first field observation of an eared insect ignoring audible but innocuous sounds.

  6. Improved insecticidal toxicity by fusing Cry1Ac of Bacillus thuringiensis with Av3 of Anemonia viridis.

    Yan, Fu; Cheng, Xing; Ding, Xuezhi; Yao, Ting; Chen, Hanna; Li, Wenping; Hu, Shengbiao; Yu, Ziquan; Sun, Yunjun; Zhang, Youming; Xia, Liqiu

    2014-05-01

    Av3, a neurotoxin of Anemonia viridis, is toxic to crustaceans and cockroaches but inactive in mammals. In the present study, Av3 was expressed in Escherichia coli Origami B (DE3) and purified by reversed-phase liquid chromatography. The purified Av3 was injected into the hemocoel of Helicoverpa armigera, rendering the worm paralyzed. Then, Av3 was expressed alone or fusion expressed with the Cry1Ac in acrystalliferous strain Cry(-)B of Bacillus thuringiensis. The shape of Cry1Ac was changed by fusion with Av3. The expressed fusion protein, Cry1AcAv3, formed irregular rhombus- or crescent-shaped crystalline inclusions, which is quite different from the shape of original Cry1Ac crystals. The toxicity of Cry1Ac was improved by fused expression. Compared with original Cry1Ac expressed in Cry(-)B, the oral toxicity of Cry1AcAv3 to H. armigera was elevated about 2.6-fold. No toxicity was detected when Av3 was expressed in Cry(-)B alone. The present study confirmed that marine toxins could be used in bio-control and implied that fused expression with other insecticidal proteins could be an efficient way for their application.

  7. Conserved chemosensory proteins in the proboscis and eyes of Lepidoptera.

    Zhu, Jiao; Iovinella, Immacolata; Dani, Francesca Romana; Liu, Yu-Ling; Huang, Ling-Qiao; Liu, Yang; Wang, Chen-Zhu; Pelosi, Paolo; Wang, Guirong

    2016-01-01

    Odorant-binding proteins (OBPs) and chemosensory proteins (CSPs) are endowed with several different functions besides being carriers for pheromones and odorants. Based on a previous report of a CSP acting as surfactant in the proboscis of the moth Helicoverpa armigera , we revealed the presence of orthologue proteins in two other moths Plutella xylostella and Chilo suppressalis , as well as two butterflies Papilio machaon and Pieris rapae , using immunodetection and proteomic analysis. The unusual conservation of these proteins across large phylogenetic distances indicated a common specific function for these CSPs. This fact prompted us to search for other functions of these proteins and discovered that CSPs are abundantly expressed in the eyes of H. armigera and possibly involved as carriers for carotenoids and visual pigments. This hypothesis is supported by ligand-binding experiments and docking simulations with retinol and β-carotene. This last orange pigment, occurring in many fruits and vegetables, is an antioxidant and the precursor of visual pigments. We propose that structurally related CSPs solubilise nutritionally important carotenoids in the proboscis, while they act as carriers of both β-carotene and its derived products 3-hydroxyretinol and 3-hydroxyretinal in the eye. The use of soluble olfactory proteins, such as CSPs, as carriers for visual pigments in insects, here reported for the first time, parallels the function of retinol-binding protein in vertebrates, a lipocalin structurally related to vertebrate odorant-binding proteins.

  8. Baseline sensitivity of lepidopteran corn pests in India to Cry1Ab insecticidal protein of Bacillus thuringiensis.

    Jalali, Sushil K; Lalitha, Yadavalli; Kamath, Subray P; Mohan, Komarlingam S; Head, Graham P

    2010-08-01

    Genetically engineered corn (Bt corn) expressing Bacillus thuringiensis Berliner insecticidal protein Cry1Ab is a biotechnological option being considered for management of lepidopteran corn pests in India. As a resistance management practice it was essential to determine the sensitivity of multiple populations of the stalk borer Chilo partellus (Swinhoe), pink borer Sesamia inferens (Walker) and the cob borer Helicoverpa armigera (Hübner) to Cry1Ab protein through bioassays. The insect populations were collected during growing seasons of Rabi 2005 (October 2005 to February 2006) and Kharif 2006 (May to September 2006). Multiple populations of the three lepidopteran corn pests were found to be susceptible to Cry1Ab. Median lethal concentrations (LC(50)) ranged between 0.008 and 0.068 microg Cry1Ab mL(-1) diet for 18 populations of C. partellus (across two seasons), between 0.12 and 1.99 microg mL(-1) for seven populations of H. armigera and between 0.46 and 0.56 microg mL(-1) for two populations of S. inferens. Dose-response concentrations for lethality and growth inhibition have been determined to mark baseline sensitivity of multiple populations of key lepidopteran corn pests in India to Cry1Ab protein. These benchmark values will be referenced while monitoring resistance to Cry1Ab should Bt corn hybrids expressing Cry1Ab be approved for commercial cultivation in India. Copyright (c) 2010 Society of Chemical Industry.

  9. Weakening density dependence from climate change and agricultural intensification triggers pest outbreaks: a 37-year observation of cotton bollworms.

    Ouyang, Fang; Hui, Cang; Ge, Saiying; Men, Xin-Yuan; Zhao, Zi-Hua; Shi, Pei-Jian; Zhang, Yong-Sheng; Li, Bai-Lian

    2014-09-01

    Understanding drivers of population fluctuation, especially for agricultural pests, is central to the provision of agro-ecosystem services. Here, we examine the role of endogenous density dependence and exogenous factors of climate and human activity in regulating the 37-year population dynamics of an important agricultural insect pest, the cotton bollworm (Helicoverpa armigera), in North China from 1975 to 2011. Quantitative time-series analysis provided strong evidence explaining long-term population dynamics of the cotton bollworm and its driving factors. Rising temperature and declining rainfall exacerbated the effect of agricultural intensification on continuously weakening the negative density dependence in regulating the population dynamics of cotton bollworms. Consequently, ongoing climate change and agricultural intensification unleashed the tightly regulated pest population and triggered the regional outbreak of H. armigera in 1992. Although the negative density dependence can effectively regulate the population change rate to fluctuate around zero at stable equilibrium levels before and after outbreak in the 1992, the population equilibrium jumped to a higher density level with apparently larger amplitudes after the outbreak. The results highlight the possibility for exogenous factors to induce pest outbreaks and alter the population regulating mechanism of negative density dependence and, thus, the stable equilibrium of the pest population, often to a higher level, posing considerable risks to the provision of agro-ecosystem services and regional food security. Efficient and timely measures of pest management in the era of Anthropocene should target the strengthening and revival of weakening density dependence caused by climate change and human activities.

  10. Competitiveness value of the indian meal, plodia interpunctella (Hub). irradiated as full grown pupae

    Ahmed, M.Y.Y.; Elhawary, I.S.; Boshra, S.A.

    1992-01-01

    When 6-day-old pupae of the indian meal moth, plodia interpunctella (Hubner) were treated with 60 K.rad, the resulting adults were sterile when they paired with the untreated opposite sex. A ratio of 1:1:1 irradiated males, in irradiated males, and unirradiated females resulted in 41.0% infertile eggs. Ratios of irradiated to unirradiated males of 5:1, 10:1, 15:1, 20:1, or 25:1 produced 75.7, 91.7, 95.0 and 96.3% infertile eggs, respectively. Thus, irradiated males were competitive only at a ratio of 25:1. When both irradiated males and females were placed with unirradiated males and females to give ratios of 1:1:1:1, 5:5:1:1, 10:10:1:1: or 15:15:1:1:, the percentage of infertile eggs were 55.7, 81.0, 95.3, and 100.0% respectively, and competitiveness was good at all but the lowest ratio. Irradiation of 6-day-old pupae of the indian meal moth produced sexually competitive sterile adults when released at high flooding ratios, and results were better when both sexes released together.2 tab

  11. Identification of volatile sex pheromone components released by the southern armyworm,Spodoptera eridania (Cramer).

    Teal, P E; Mitchell, E R; Tumlinson, J H; Heath, R R; Sugie, H

    1985-06-01

    Analysis of sex pheromone gland extracts and volatile pheromone components collected from the calling female southern armyworm,Spodoptera eridania (Cramer), by high-resolution capillary gas chromatography and mass spectroscopy indicated that a number of 14-carbon mono- and diunsaturated acetates and a monounsaturated 16-carbon acetate were produced. Gland extracts also indicated the presence of (Z)-9-tetradecen-1-ol. However, this compound was not found in collections of volatiles. Field trapping studies indicated that the volatile blend composed of (Z)-9-tetradecen-1-ol acetate (60%), (Z)-9-(E)-12-tetradecadien-1-ol acetate (17%), (Z)-9-(Z)-12-tetradecadien-1-ol acetate (15%), (Z)-9-(E)-11-tetradecadien-1-ol acetate (5%), and (Z)-11-hexadecen-1-ol acetate (3 %) was an effective trap bait for males of this species. The addition of (Z)-9-tetradecen-1-ol to the acetate blends tested resulted in the capture of beet armyworm,S. exigua (Hubner), males which provides further evidence that the alcohol is a pheromone component of this species.

  12. INFLUENCE OF EUROPEAN CORN BORER (Ostrinia nubilalis Hübner ON CORN HYBRIDS IN NORTH-WEST AND EASTERN CROATIA

    Zvjezdana Augustinović

    2005-12-01

    Full Text Available European corn borer (Ostrinia nubilalis Hubner is one of the major corn pest in the world and in Croatia. Former investigations of corn borer in Croatia covered mostly its Eastern region. In trials conducted in 1998 and 1999 the research was extended to the North Western part of Croatia too. Macro trials were carried out with corn hybrids of FAO groups 200-600 at three localities: Križevci, Agricultural institute Osijek and at «Belje» PIK Karanac. In 1998 the intensity of the corn borer attack at the locality of «Belje» PIK Karanac was about 37.92% and in Agricultural institute Osijek 80.83%. In 1999 it varied between 37.08% at the locality of Agricultural Institute Osijek and 71.20% at the locality in Križevci. The estimated number of holes per plant in all three localities in both years was higher than the number of caterpillars. Length of damage per plant was between 0.38 and 18.80 cm. The data showed significant differences in the intensity of damaging effects on different localities while no significant differences concerning various hybrids were found. The statistical data concerning yield in both years showed significant differences among hybrids, localities and their interactions.

  13. EFFICIENCY OF THE CHEMICAL TREATMENT AGAINST THE EUROPEAN CORN BORER IN SEED MAIZE PRODUCTION

    Emilija Raspudić

    2013-06-01

    Full Text Available The aim of this study was to determine the effectiveness of a chemical treatment against larvae of the European corn borer (Ostrinia nubilalis Hubner. The experiment was set up in 2010 and 2011 in Čepin (eastern Croatia in two treatments: control treatment and insecticide treatment. The trial involved two hybrids of FAO group 400: PR37N01 and PR37F73. Biology of pests was monitored in order to determine population size and larvae development stage as well as the optimal time of insecticide application. After determination of thresholds, maize was treated with chemical formulations of active substance dimethoate. Towards the end of vegetation, length of stem damage, number of larvae in maize stalk and ear as well as grain yield were recorded by dissection of maize stalks. Statistical analysis shows that year, hybrid and chemical treatment significantly influenced the incidence of this pest and justified the use of chemical preparations with mandatory monitoring biology of this pest.

  14. Insecticidal effects of Moroccan plant extracts on development, energy reserves and enzymatic activities of Plodia interpunctella

    Bouayard, N.; Rharrabe, K.; Ghailani, N. N.; Jbilou, R.; Castanera, P.; Ortego, F.

    2013-05-01

    The aim of this work was to study the effects of methanol extracts of ten plant species used in traditional medicine in Morocco (Peganum harmala, Ajuga iva, Rosmarinus officinalis, Lavandula stoechas, Lavandula dentata, Cistus ladanifer, Cistus salviaefolius, Cistus monspeliensis, Centaurium erythraea and Launaea arborescens) on Plodia interpunctella Hubner (Lepidoptera: Pyralidae) larvae. Firstly, we studied the effects of the ingestion of these extracts at 500 ppm on post-embryonic development parameters. Most plant extracts provoked a notable decrease of larval weight 8 days after treatment (up to 33% weight loss with C. erythraea) and caused significant alterations on pupation (ranging from 5% to 85%) and adult emergence (below 2.5% with R. officinalis, C. erythraea and A. iva). The plant extracts that showed strongest effects on post-embryonic development were selected to test their effects on the following physiological parameters: larval reserve substances (at 500 ppm); and midgut activities of hydrolytic and detoxification enzymes (at 500, 750 and 1000 ppm). All treatments provoked a significant reduction of protein and carbon hydrate larval contents, the inhibition of proteases and {alpha}-amylase activities in a dose depended manner, and the induction of glutathione S-transferase and esterase (using MtB as substrate) activities, whereas the activity of cytochrome P450 monooxygenases and esterases (using 1-NA as substrate) increase or decrease depending on the extract concentration and the plant analyzed. (Author) 65 refs.

  15. De novo biosynthesis of volatiles induced by insect herbivory in cotton plants

    Pare, P.W.; Tumlinson, J.H.

    1997-01-01

    In response to insect feeding on the leaves, cotton (Gossypium hirsutum L.) plants release elevated levels of volatiles, which can serve as a chemical signal that attracts natural enemies of the herbivore to the damaged plant. Pulse-labeling experiments with [13C]CO2 demonstrated that many of the volatiles released, including the acyclic terpenes (E,E)-alpha-farnesene, (E)-beta-farnesene, (E)-beta-ocimene, linalool,(E)-4,8-dimethyl-1,3,7-nonatriene, and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetrane, as well as the shikimate pathway product indole, are biosynthesized de novo following insect damage. However, other volatile constituents, including several cyclic terpenes, butyrates, and green leaf volatiles of the lipoxygenase pathway are released from storage or synthesized from stored intermediates. Analysis of volatiles from artificially damaged plants, with and without beet armyworm (Spodoptera exigua Hubner) oral secretions exogenously applied to the leaves, as well as volatiles from beet armyworm-damaged and -undamaged control plants, demonstrated that the application of caterpillar oral secretions increased both the production and release of several volatiles that are synthesized de novo in response to insect feeding. These results establish that the plant plays an active and dynamic role in mediating the interaction between herbivores and natural enemies of herbivores

  16. Academic Training: Academic Training Programme 50th Anniversary Lectures

    Françoise Benz

    2004-01-01

    13, 14, 15 & 16 September From 16:30 hrs - Main Auditorium bldg. 500 50 years of research at CERN: from past to future Monday 13 September 50 years of research at CERN: from past to future (Accelerator) (1/4) K. Hubner / CERN-DSU A summary of the evolution of the CERN accelerator complex since the beginning will be given. The emphasis will be on the salient features and highlights and what has been learned at each stage in terms of accelerator physics and technology. Possible future options for CERN based on accelerators will be discussed. Tuesday 14 September 50 years of research at CERN: from past to future (Theory) (2/4) G. Veneziano / CERN-PH-TH Great developments in our understanding of fundamental physics, together with striking technological advances, have repeatedly changed the way CERN/TH has been operating during the past 50 years. I will outline the main 'revolutions' I have myself witnessed at CERN/TH since the mid sixties, and then dare to express expectations, hopes, and fears for how ...

  17. Effects of 60Co irradiation on the genetics of indian meal moth

    Yang Changju; Liu Ganming; Deng Wangxi; Yang Zhihui; Hu Jianfang

    1993-01-01

    4 ∼ 5 days old male pupae of Indian meal moth, Plodia interpunctella Hubner were irradiated with 1, 3, 5, 7 and 10 krad of 60 Co γ-ray. The male moths developed from treated pupae and their F 1 generation were put together with normal female moths for copulation separately. The genetic effects of irradiation was studied and the results showed that the effects of irradiation were significant, which related to the irradiation dosage, on both parental and filial generations. Only 40% of the pupae was emerged, when they were irradiated at 10 krad. The effects on deformation rates, survival rates, copulation abilities, fecundities, hatching rates and genetic sterilities varied with different irradiation dosage treatment. With consideration of the total irradiation effect, the dosage lower than 5 krad is desirable for inducing the sterility of adults and sex chain recessive lethal gene. With 1, 5 and 7 krad of irradiation, a mutant of P. interpunctella with transparent wings was induced, which provides a marking feature in control of Indian meal moth by sex chain recessive lethal gene

  18. 1754 Days to the LHC and counting!

    2001-01-01

    At the 118th session of CERN Council, held on Friday 15 June under the chairmanship of Professor Maurice Bourquin of Switzerland, Director-General, Luciano Maiani, presented the commissioning schedule for the Large Hadron Collider (LHC) for the first time. The LHC will collide its first beams in a pilot run starting on 1 April 2006. 'We are 1754 days from the LHC', said Professor Maiani. A full seven-month physics run will begin in August 2006, and the LHC's heavy-ion programme will start in February 2007. Left to right: Lyn Evans, Luciano Maiani, Alexander Skrinsky, and Kurt Hubner with the magnets from Novosibirsk. Professor Maiani underlined to Council that the LHC is now CERN's most important single activity, accounting for over 70% of the Laboratory's resources. Moreover, with some 70% of the total LHC cost adjudicated and 30% paid, the project is very far advanced. With the adjudication this Autumn of the contracts for the 1236 fifteen metre superconducting dipole magnets, the placing of major contrac...

  19. Species phylogeny of the subgenus parides (Lepidoptera: papilionidae) based in sequences of citochrome oxidase I gene

    Gutierrez R, Ingrid Marcela; Fagua, Giovanny

    2012-01-01

    Parides hubner is a terminal taxon of troidini, an aposematic butterfly group that is diverse in the tropics and subtropics, and a model of Mullerian and Batesian mimetic complexes. Several American species of parides are sympatric and include populations with intraspecific variation in color pattern, thus creating confusion on their taxonomic status, mainly in Colombia where the biota of North and South America converge. This work presents a phylogenetic hypothesis of these butterflies and proposes a more robust definition of some taxa. For this, 15 taxa of the subgenus parides were analyzed as ingroup; species of other two genera of troidini, closer to parides, were used as out-group. DNA was extracted using the pascual et al. (1997) protocol and quiagen dnaeasy kit. A terminal fragment of cytochrome oxidase I gen (476 bp) were amplified. We obtained a phylogenetic approximation using maximum parsimony and evaluated the branch support with jackknife and absolute bremer support. We also conducted a bayesian analysis. The resulting phylogenetic hypothesis suggested that parides is a paraphyletic group; the molecular evidence support one species and five subspecies. The analyzed taxa were divided in three principal groups coincident with the lysander (group 1) and aeneas (groups 1 and 2) groups proposed by rothschild and jordan (1906).

  20. Binding site alteration is responsible for field-isolated resistance to Bacillus thuringiensis Cry2A insecticidal proteins in two Helicoverpa species.

    Silvia Caccia

    Full Text Available BACKGROUND: Evolution of resistance by target pests is the main threat to the long-term efficacy of crops expressing Bacillus thuringiensis (Bt insecticidal proteins. Cry2 proteins play a pivotal role in current Bt spray formulations and transgenic crops and they complement Cry1A proteins because of their different mode of action. Their presence is critical in the control of those lepidopteran species, such as Helicoverpa spp., which are not highly susceptible to Cry1A proteins. In Australia, a transgenic variety of cotton expressing Cry1Ac and Cry2Ab (Bollgard II comprises at least 80% of the total cotton area. Prior to the widespread adoption of Bollgard II, the frequency of alleles conferring resistance to Cry2Ab in field populations of Helicoverpa armigera and Helicoverpa punctigera was significantly higher than anticipated. Colonies established from survivors of F(2 screens against Cry2Ab are highly resistant to this toxin, but susceptible to Cry1Ac. METHODOLOGY/PRINCIPAL FINDINGS: Bioassays performed with surface-treated artificial diet on neonates of H. armigera and H. punctigera showed that Cry2Ab resistant insects were cross-resistant to Cry2Ae while susceptible to Cry1Ab. Binding analyses with (125I-labeled Cry2Ab were performed with brush border membrane vesicles from midguts of Cry2Ab susceptible and resistant insects. The results of the binding analyses correlated with bioassay data and demonstrated that resistant insects exhibited greatly reduced binding of Cry2Ab toxin to midgut receptors, whereas no change in (125I-labeled-Cry1Ac binding was detected. As previously demonstrated for H. armigera, Cry2Ab binding sites in H. punctigera were shown to be shared by Cry2Ae, which explains why an alteration of the shared binding site would lead to cross-resistance between the two Cry2A toxins. CONCLUSION/SIGNIFICANCE: This is the first time that a mechanism of resistance to the Cry2 class of insecticidal proteins has been reported

  1. Genetically pyramiding protease-inhibitor genes for dual broad-spectrum resistance against insect and phytopathogens in transgenic tobacco.

    Senthilkumar, Rajendran; Cheng, Chiu-Ping; Yeh, Kai-Wun

    2010-01-01

    Protease inhibitors provide a promising means of engineering plant resistance against attack by insects and pathogens. Sporamin (trypsin inhibitor) from sweet potato and CeCPI (phytocystatin) from taro were stacked in a binary vector, using pMSPOA (a modified sporamin promoter) to drive both genes. Transgenic tobacco lines of T0 and T1 generation with varied inhibitory activity against trypsin and papain showed resistance to both insects and phytopathogens. Larvae of Helicoverpa armigera that ingested tobacco leaves either died or showed delayed growth and development relative to control larvae. Transgenic tobacco-overexpressing the stacked genes also exhibited strong resistance against bacterial soft rot disease caused by Erwinia carotovora and damping-off disease caused by Pythium aphanidermatum. Thus, stacking protease-inhibitor genes, driven by the wound and pathogen responsive pMSPOA promoter, is an effective strategy for engineering crops to resistance against insects and phytopathogens.

  2. Screening of broad spectrum natural pesticides against conserved target arginine kinase in cotton pests by molecular modeling.

    Sakthivel, Seethalakshmi; Habeeb, S K M; Raman, Chandrasekar

    2018-03-12

    Cotton is an economically important crop and its production is challenged by the diversity of pests and related insecticide resistance. Identification of the conserved target across the cotton pest will help to design broad spectrum insecticide. In this study, we have identified conserved sequences by Expressed Sequence Tag profiling from three cotton pests namely Aphis gossypii, Helicoverpa armigera, and Spodoptera exigua. One target protein arginine kinase having a key role in insect physiology and energy metabolism was studied further using homology modeling, virtual screening, molecular docking, and molecular dynamics simulation to identify potential biopesticide compounds from the Zinc natural database. We have identified four compounds having excellent inhibitor potential against the identified broad spectrum target which are highly specific to invertebrates.

  3. Application of radioisotopes in entomology

    Saour, G.

    1995-01-01

    Radioisotope techniques are effective in entomology and studies on insects physiology. The study presents the use of radioisotopes in pest control programs: Methods of insects irradiation and the concept of biological half-life of the radioisotopes in comparison with physical half-life are explained. Main radioisotopes used in entomology are: 3 H, 14 Ca, 32 P, 35 S, 38 Cl. Other radioisotopes contributing to studies on insects are: 198 Au, 134 Cs, 131 I, 86 Rb, 65 Zn, 59 Fe, 45 Ca, 24 Na, 22 Na. Radiation doses specific to each radioisotopes are given in tables. As an example of the application of radioisotopes in pest control: the determination of insects population density by means of releasing irradiated male insects than chasing them; studying of reproduction activity of Agrotis ipsilon; studying of egg laying of Heliocoverpa armigera moth. 15 refs. 2 figs. 2 tabs

  4. Application of radioisotopes in entomology

    Saour, G [Atomic Energy Commission, Damascus (Syrian Arab Republic). Dept. of Radiation Agriculture

    1995-10-01

    Radioisotope techniques are effective in entomology and studies on insects physiology. The study presents the use of radioisotopes in pest control programs: Methods of insects irradiation and the concept of biological half-life of the radioisotopes in comparison with physical half-life are explained. Main radioisotopes used in entomology are:{sup 3}H, {sup 14}Ca, {sup 32}P, {sup 35}S, {sup 38}Cl. Other radioisotopes contributing to studies on insects are: {sup 198}Au, {sup 134}Cs, {sup 131}I, {sup 86}Rb, {sup 65}Zn, {sup 59}Fe, {sup 45}Ca, {sup 24}Na, {sup 22}Na. Radiation doses specific to each radioisotopes are given in tables. As an example of the application of radioisotopes in pest control: the determination of insects population density by means of releasing irradiated male insects than chasing them; studying of reproduction activity of Agrotis ipsilon; studying of egg laying of Heliocoverpa armigera moth. 15 refs. 2 figs. 2 tabs.

  5. How predictable are the behavioral responses of insects to herbivore induced changes in plants? Responses of two congeneric thrips to induced cotton plants.

    Rehan Silva

    Full Text Available Changes in plants following insect attack are referred to as induced responses. These responses are widely viewed as a form of defence against further insect attack. In the current study we explore whether it is possible to make generalizations about induced plant responses given the unpredictability and variability observed in insect-plant interactions. Experiments were conducted to test for consistency in the responses of two congeneric thrips, Frankliniella schultzei Trybom and Frankliniella occidentalis Pergrande (Thysanoptera: Thripidae to cotton seedlings (Gossypium hirsutum Linneaus (Malvales: Malvaceae damaged by various insect herbivores. In dual-choice experiments that compared intact and damaged cotton seedlings, F. schultzei was attracted to seedlings damaged by Helicoverpa armigera (Hübner (Lepidoptera: Noctuidae, Tetranychus urticae (Koch (Trombidiforms: Tetranychidae, Tenebrio molitor Linnaeus (Coleoptera: Tenebrionidae, F. schultzei and F. occidentalis but not to mechanically damaged seedlings. In similar tests, F. occidentalis was attracted to undamaged cotton seedlings when simultaneously exposed to seedlings damaged by H. armigera, T. molitor or F. occidentalis. However, when exposed to F. schultzei or T. urticae damaged plants, F. occidentalis was more attracted towards damaged plants. A quantitative relationship was also apparent, F. schultzei showed increased attraction to damaged seedlings as the density of T. urticae or F. schultzei increased. In contrast, although F. occidentalis demonstrated increased attraction to plants damaged by higher densities of T. urticae, there was a negative relationship between attraction and the density of damaging conspecifics. Both species showed greater attraction to T. urticae damaged seedlings than to seedlings damaged by conspecifics. Results demonstrate that the responses of both species of thrips were context dependent, making generalizations difficult to formulate.

  6. Combination of plant and insect eggs as food sources facilitates ovarian development in an omnivorous bug Apolygus lucorum (Hemiptera: Miridae).

    Yuan, Wei; Li, Wenjing; Li, Yunhe; Wu, Kongming G

    2013-06-01

    Diet nutrient is considered as an important regulatory factor for reproduction of insects. To understand the effect of different food sources on the reproductive physiology of Apolygus lucorum (Meyer-Dür), the ovarian development in adult females was investigated when they were fed on green beans (Gb), combination of green beans Phaseolus vulgaris L and Helicoverpa armigera eggs (GbHe), or H. armigera eggs (He). A female of A. lucorum has two ovaries, and each ovary contained seven yellowish ovarioles. Females fed on Gb or GbHe had larger ovaries and the ovarioles contained larger numbers of oocytes compared with those fed on He. Females in GeHe treatment has significantly higher number of follicles per ovary throughout the whole adult period compared with those in Gb or He treatment. Furthermore, the length of the best developed ovariole was affected by the diet type. The females fed on GbHe had the most developed ovarioles, with significantly longer ovarioles than those fed on Gb or He. A method was described to quantitatively score the degree of ovarian development in the current study. Similarly, the ovarian development scores were significantly higher for females in GbHe treatment than those in other two diet treatments. The ovarian development significantly delayed for females fed on He. Our results demonstrate that A. lucorum, as an omnivorous insect species, can acquire nutrients from both plant and animal origin food sources, and the combination of plants and animal food sources can significantly facilitate the ovary development of its females.

  7. Substantial Mortality of Cabbage Looper (Lepidoptera: Noctuidae) From Predators in Urban Agriculture Is not Influenced by Scale of Production or Variation in Local and Landscape-Level Factors.

    Lowenstein, David M; Gharehaghaji, Maryam; Wise, David H

    2017-02-01

    As Midwestern (United States) cities experience population decline, there is growing interest in converting underutilized vacant spaces to agricultural production. Urban agriculture varies in area and scope, yet most growers use similar cultivation practices such as avoiding chemical control of crop pests. For community gardens and farms that sell produce commercially, effective pest suppression by natural enemies is important for both societal, economic, and marketing reasons. To gauge the amount of prey suppression at 28 urban food-production sites, we measured removal of sentinel eggs and larvae of the cabbage looper Trichoplusia ni (Hubner), a caterpillar pest that defoliates Brassica. We investigated how landscape and local factors, such as scale of production, influence cabbage looper mortality caused by predators. Predators removed 50% of eggs and 25% of larvae over a 3-d period. Landscape factors did not predict mortality rates, and the amount of loss and damage to sentinel prey were similar across sites that differed in scale (residential gardens, community gardens, and farms). To confirm that removal of sentinel items was likely caused by natural enemies, we set up a laboratory assay that measured predation of cabbage looper eggs and larvae by several predators occurring in urban gardens. Lady beetles caused the highest mortality rates, suggesting their potential value for biocontrol; spiders and pirate bugs also consumed both eggs and larvae at high rates. Our results suggest that urban growers benefit from high consumption rates of cabbage looper eggs and larvae by arthropod predators. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Influence of stocking, site quality, stand age, low-severity canopy disturbance, and forest composition on sub-boreal aspen mixedwood carbon stocks

    Reinikainen, Michael; D’Amato, Anthony W.; Bradford, John B.; Fraver, Shawn

    2014-01-01

    Low-severity canopy disturbance presumably influences forest carbon dynamics during the course of stand development, yet the topic has received relatively little attention. This is surprising because of the frequent occurrence of such events and the potential for both the severity and frequency of disturbances to increase as a result of climate change. We investigated the impacts of low-severity canopy disturbance and average insect defoliation on forest carbon stocks and rates of carbon sequestration in mature aspen mixedwood forests of varying stand age (ranging from 61 to 85 years), overstory composition, stocking level, and site quality. Stocking level and site quality positively affected the average annual aboveground tree carbon increment (CAAI), while stocking level, site quality, and stand age positively affected tree carbon stocks (CTREE) and total ecosystem carbon stocks (CTOTAL). Cumulative canopy disturbance (DIST) was reconstructed using dendroecological methods over a 29-year period. DIST was negatively and significantly related to soil carbon (CSOIL), and it was negatively, albeit marginally, related to CTOTAL. Minima in the annual aboveground carbon increment of trees (CAI) occurred at sites during defoliation of aspen (Populus tremuloides Michx.) by forest tent caterpillar (Malacosoma disstria Hubner), and minima were more extreme at sites dominated by trembling aspen than sites mixed with conifers. At sites defoliated by forest tent caterpillar in the early 2000s, increased sequestration by the softwood component (Abies balsamea (L.) Mill. and Picea glauca (Moench) Voss) compensated for overall decreases in CAI by 17% on average. These results underscore the importance of accounting for low-severity canopy disturbance events when developing regional forest carbon models and argue for the restoration and maintenance of historically important conifer species within aspen mixedwoods to enhance stand-level resilience to disturbance agents and maintain

  9. Sequential sampling and biorational chemistries for management of lepidopteran pests of vegetable amaranth in the Caribbean.

    Clarke-Harris, Dionne; Fleischer, Shelby J

    2003-06-01

    Although vegetable amaranth, Amaranthus viridis L. and A. dubius Mart. ex Thell., production and economic importance is increasing in diversified peri-urban farms in Jamaica, lepidopteran herbivory is common even during weekly pyrethroid applications. We developed and validated a sampling plan, and investigated insecticides with new modes of action, for a complex of five species (Pyralidae: Spoladea recurvalis (F.), Herpetogramma bipunctalis (F.), Noctuidae: Spodoptera exigua (Hubner), S. frugiperda (J. E. Smith), and S. eridania Stoll). Significant within-plant variation occurred with H. bipunctalis, and a six-leaf sample unit including leaves from the inner and outer whorl was selected to sample all species. Larval counts best fit a negative binomial distribution. We developed a sequential sampling plan using a threshold of one larva per sample unit and the fitted distribution with a k(c) of 0.645. When compared with a fixed plan of 25 plants, sequential sampling recommended the same management decision on 87.5%, additional samples on 9.4%, and gave inaccurate recommendations on 3.1% of 32 farms, while reducing sample size by 46%. Insecticide frequency was reduced 33-60% when management decisions were based on sampled data compared with grower-standards, with no effect on crop damage. Damage remained high or variable (10-46%) with pyrethroid applications. Lepidopteran control was dramatically improved with ecdysone agonists (tebufenozide) or microbial metabolites (spinosyns and emamectin benzoate). This work facilitates resistance management efforts concurrent with the introduction of newer modes of action for lepidopteran control in leafy vegetable production in the Caribbean.

  10. Consumption and utilization of experimentally altered corn by southern armyworm: Iron, nitrogen, and cyclic hydroxamates.

    Manuwoto, S; Scriber, J M

    1985-11-01

    The effects of differential leaf water, leaf nitrogen and cyclic hydroxamate (DIMBOA) concentrations in corn seedlings were analyzed for a polyphagous insect, the southern armyworm (Spodoptera eridania Cram.). Six different combinations of nutrients and allelochemicals [DIMBOA = 2,4-dihydroxy-7-methoxy(2H)-benzoxazin-3(4H)-one] were generated using two corn genotypes (WF9 and CI3IA) and three fertility regimes (complete nutrient, Fe-deficient, and N-deficient solutions) in the University Biotron. Poorest larval growth was observed in the low-nitrogen treatments (1.2% and 1.7% leaf N) and was the result of both low consumption rates and high metabolic costs (low efficiency of conversion of digested food, ECD). Fastest growth rates were observed forthe larvae fed leaves from the high-nitrogen treatments (4.6% and 4.4% leaf N). It is noteworthy that these treatments also contained the highest concentration of cyclic hydroxamates, which are generally believed to be the primary defensive chemicals mediating resistance against the European corn borer,Ostrinia nubilalis (Hubner). If these hydroxamates do have any deleterious or costly effects (perhaps accounting for a large portion of metabolic expenditures), the high digestibility of the leaf tissue and the increased consumption rates more than compensate, resulting in rapid growth (growth rate = consumption rate × approximate digestibility × efficiency of conversion of the digested food). These studies illustrate that variation in key nutrients and allelochemicals within a single plant species (Zea mays L.) may have significantly different effects upon various potential leaf-chewing caterpillars, such as these armyworms versus corn borers (which cannot handle the cyclic hydroxamates, even if provided with young nutritious leaf tissues).

  11. Bt Jute Expressing Fused δ-Endotoxin Cry1Ab/Ac for Resistance to Lepidopteran Pests

    Shuvobrata Majumder

    2018-01-01

    Full Text Available Jute (Corchorus sp. is naturally occurring, biodegradable, lignocellulosic-long, silky, golden shiny fiber producing plant that has great demands globally. Paper and textile industries are interested in jute because of the easy availability, non-toxicity and high yield of cellulosic biomass produced per acre in cultivation. Jute is the major and most industrially used bast fiber-producing crop in the world and it needs protection from insect pest infestation that decreases its yield and quality. Single locus integration of the synthetically fused cry1Ab/Ac gene of Bacillus thuringiensis (Bt in Corchorus capsularis (JRC 321 by Agrobacterium tumefaciens-mediated shoot tip transformation provided 5 potent Bt jute lines BT1, BT2, BT4, BT7 and BT8. These lines consistently expressed the Cry1Ab/Ac endotoxin ranging from 0.16 to 0.35 ng/mg of leaf, in the following generations (analyzed upto T4. The effect of Cry1Ab/Ac endotoxin was studied against 3 major Lepidopteran pests of jute- semilooper (Anomis sabulifera Guenee, hairy caterpillar (Spilarctia obliqua Walker and indigo caterpillar (Spodoptera exigua Hubner by detached leaf and whole plant insect bioassay on greenhouse-grown transgenic plants. Results confirm that larvae feeding on transgenic plants had lower food consumption, body size, body weight and dry weight of excreta compared to non-transgenic controls. Insect mortality range among transgenic feeders was 66–100% for semilooper and hairy caterpillar and 87.50% for indigo caterpillar. Apart from insect resistance, the transgenic plants were at par with control plants in terms of agronomic parameters and fiber quality. Hence, these Bt jutes in the field would survive Lepidopteran pest infestation, minimize harmful pesticide usage and yield good quality fiber.

  12. Insect radiosensitivity: dose curves and dose-fractionation studies of dominant lethal mutations in the mature sperm of 4 insect species

    LaChance, L.E.; Graham, C.K.

    1984-01-01

    Males of 4 species of insects: Musca domestica L. (housefly) (Diptera), Oncopeltus fasciatus (Dallas) (milkweed bug) (Hemiptera), Anagasta kuhniella (Zeller) (mealmoth) (Lepidoptera) and Heliothis virescens (Fab.) (tobacco budworm) (Lepidoptera) were irradiated as adults. Dose-response curves for the induction of dominant lethal mutations in the mature sperm were constructed. The curves were analyzed mathematically and compared with theoretical computer simulated curves requiring 1, 2, 4, 8 and 16 'hits' for the induction of a dominant lethal mutation. The 4 species belonging to 3 different orders of insects showed a wide range in radiation sensitivity and vastly different dose-response curves. When the data were analyzed by several mathematical models the authors found that a logistic response curve gave reasonably good fit with vastly different parameters for the 4 species. Dose-fractionation experiments showed no reduction in the frequency of lethal mutations induced in any species when an acute dose was fractionated into 2 equal exposures separated by an 8-h period. (Auth.)

  13. The Dynamics of Pheromone Gland Synthesis and Release: a Paradigm Shift for Understanding Sex Pheromone Quantity in Female Moths.

    Foster, Stephen P; Anderson, Karin G; Casas, Jérôme

    2018-05-10

    Moths are exemplars of chemical communication, especially with regard to specificity and the minute amounts they use. Yet, little is known about how females manage synthesis and storage of pheromone to maintain release rates attractive to conspecific males and why such small amounts are used. We developed, for the first time, a quantitative model, based on an extensive empirical data set, describing the dynamical relationship among synthesis, storage (titer) and release of pheromone over time in a moth (Heliothis virescens). The model is compartmental, with one major state variable (titer), one time-varying (synthesis), and two constant (catabolism and release) rates. The model was a good fit, suggesting it accounted for the major processes. Overall, we found the relatively small amounts of pheromone stored and released were largely a function of high catabolism rather than a low rate of synthesis. A paradigm shift may be necessary to understand the low amounts released by female moths, away from the small quantities synthesized to the (relatively) large amounts catabolized. Future research on pheromone quantity should focus on structural and physicochemical processes that limit storage and release rate quantities. To our knowledge, this is the first time that pheromone gland function has been modeled for any animal.

  14. Interactions between the jasmonic and salicylic acid pathway modulate the plant metabolome and affect herbivores of different feeding types.

    Schweiger, R; Heise, A-M; Persicke, M; Müller, C

    2014-07-01

    The phytohormones jasmonic acid (JA) and salicylic acid (SA) mediate induced plant defences and the corresponding pathways interact in a complex manner as has been shown on the transcript and proteine level. Downstream, metabolic changes are important for plant-herbivore interactions. This study investigated metabolic changes in leaf tissue and phloem exudates of Plantago lanceolata after single and combined JA and SA applications as well as consequences on chewing-biting (Heliothis virescens) and piercing-sucking (Myzus persicae) herbivores. Targeted metabolite profiling and untargeted metabolic fingerprinting uncovered different categories of plant metabolites, which were influenced in a specific manner, indicating points of divergence, convergence, positive crosstalk and pronounced mutual antagonism between the signaling pathways. Phytohormone-specific decreases of primary metabolite pool sizes in the phloem exudates may indicate shifts in sink-source relations, resource allocation, nutrient uptake or photosynthesis. Survival of both herbivore species was significantly reduced by JA and SA treatments. However, the combined application of JA and SA attenuated the negative effects at least against H. virescens suggesting that mutual antagonism between the JA and SA pathway may be responsible. Pathway interactions provide a great regulatory potential for the plant that allows triggering of appropriate defences when attacked by different antagonist species. © 2013 John Wiley & Sons Ltd.

  15. Sex-specific consequences of an induced immune response on reproduction in a moth.

    Barthel, Andrea; Staudacher, Heike; Schmaltz, Antje; Heckel, David G; Groot, Astrid T

    2015-12-16

    Immune response induction benefits insects in combatting infection by pathogens. However, organisms have a limited amount of resources available and face the dilemma of partitioning resources between immunity and other life-history traits. Since males and females differ in their life histories, sex-specific resource investment strategies to achieve an optimal immune response following an infection can be expected. We investigated immune response induction of females and males of Heliothis virescens in response to the entomopathogenic bacterium Serratia entomophila, and its effects on mating success and the female sexual signal. We found that females had higher expression levels of immune-related genes after bacterial challenge than males. However, males maintained a higher baseline expression of immune-related genes than females. The increased investment in immunity of female moths was negatively correlated with mating success and the female sexual signal. Male mating success was unaffected by bacterial challenge. Our results show that the sexes differed in their investment strategies: females invested in immune defense after a bacterial challenge, indicating facultative immune deployment, whereas males had higher baseline immunity than females, indicating immune maintenance. Interestingly, these differences in investment were reflected in the mate choice assays. As female moths are the sexual signallers, females need to invest resources in their attractiveness. However, female moths appeared to invest in immunity at the cost of reproductive effort.

  16. Effects of copper and tributyltin on stress protein abundance in the rotifer Brachionus plicatilis.

    Cochrane, B J; Irby, R B; Snell, T W

    1991-01-01

    1. Exposure of the rotifer Brachionus plicatilis to elevated temperature resulted in the synthesis of a number of proteins, including a prominent one of 58,000 Da (SP58). 2. This protein is immunologically crossreactive with the 65,000 Da heat shock protein of the moth Heliothis virescens, which is a member of a highly conserved family of mitochondrial proteins. 3. Exposure of rotifers to sublethal doses of CuSO4 leads to a 4-5-fold increase in abundance of SP58, with maximum increase occurring at a dose that is approximately 5% of the LC50 for that compound. 4. A similar response was seen with tributyl tin (TBT). Kinetics of induction were sigmoidal, with induction occurring in the range of 20-30 micrograms/l. 5. No response was observed when rotifers were exposed to aluminum chloride, mercury chloride, pentachlorophenol, sodium arsenite, sodium azide, sodium dodecyl sulfate, or zinc chloride. 6. These results indicate that changes in stress protein abundance may prove useful as a biomarker of exposure to particular toxicants.

  17. Toxicities of emamectin benzoate homologues and photodegradates to Lepidoptera.

    Argentine, Joseph A; Jansson, Richard K; Starner, Van R; Halliday, W Ross

    2002-12-01

    The toxicity of a number of emamectin benzoate homologues and photodegradates to five species of Lepidoptera was investigated using diet and foliar bioassays. The emamectin benzoate homologues B1a and B1b were equally toxic in the diet and foliar assays to Spodoptera exigua (Hübner), Heliothis virescens (F.), Tricoplusia ni (Hübner), and Spodoptera frugiperda (J. E. Smith), within each of these species. Plutella xylostella (L.) was the most sensitive species to emamectin benzoate. The AB1a photodegradate of emamectin benzoate was as toxic as the parent compound in the diet assay. However, in the foliage assay AB1a was 4.4-fold less toxic to S. exigua than the parent compound. The MFB1a photodegradate of emamectin benzoate was as toxic as the parent compound to P. xylostella, and 3.1 to 6.2 times as toxic as the parent compound to the other species in the diet assay. The order of toxicity of the photodegradates were AB1a > MFB1a > FAB1a > 8,9-Z-MAB1a > PAB1a.

  18. Synthesis and metabolism of pheromones and pheromone analogues

    Ding, Y.S.

    1987-01-01

    [9, 10- 3 H 2 ]Z9-14:Ac was synthesized at high specific activity ( 3 H, 58 Ci/mmole) by partial tritiation of the corresponding alkyne and was converted to the labeled Z9-14:OH and Z9-14:Al to study tissue specificity of acetate esterase (E), alcohol oxidase (OX), and aldehyde dehydrogenase (ALDH) in male and female Heliothis virescens. Soluble and membrane-associated enzyme activities were determined by radio-TLC assays. Compounds of the tritium-labeled Z11-16 series were synthesized and their in vitro fates examined as well. In order to achieve an alternative approach in which (1) pheromone receptor proteins would be stoichiometrically and irreversibly modified, or (2) pheromone-catabolizing enzymes are inactivated by tight-binding or irreversible inhibitors, we have designed analogues of pheromones of lepidopterous insect pests and assayed their biological activity in vitro and in vivo. Various fluorinated molecules such as acyl fluorides, fluoroolefins, 2-fluoro aldehydes, 2,2-difluoro aldehydes and trifluoromethyl ketones were synthesized. The synthesis of some other functional groups such as cyclopropanones, cyclopropanols, cyclopropyl carbinols, cyclopropyl aldehydes and Michael acceptors will also be discussed

  19. Insect Larvae: A New Platform to Produce Commercial Recombinant Proteins.

    Targovnik, Alexandra M; Arregui, Mariana B; Bracco, Lautaro F; Urtasun, Nicolas; Baieli, Maria F; Segura, Maria M; Simonella, Maria A; Fogar, Mariela; Wolman, Federico J; Cascone, Osvaldo; Miranda, Maria V

    2016-01-01

    In Biotechnology, the expression of recombinant proteins is a constantly growing field and different hosts are used for this purpose. Some valuable proteins cannot be produced using traditional systems. Insects from the order Lepidoptera infected with recombinant baculovirus have appeared as a good choice to express high levels of proteins, especially those with post-translational modifications. Lepidopteran insects, which are extensively distributed in the world, can be used as small protein factories, the new biofactories. Species like Bombyx mori (silkworm) have been analyzed in Asian countries to produce a great number of recombinant proteins for use in basic and applied science and industry. Many proteins expressed in this larva have been commercialized. Several recombinant proteins produced in silkworms have already been commercialized. On the other hand, species like Spodoptera frugiperda, Heliothis virescens, Rachiplusia nu, Helicoverpa zea and Trichoplusia ni are widely distributed in both the occidental world and Europe. The expression of recombinant proteins in larvae has the advantage of its low cost in comparison with insect cell cultures. A wide variety of recombinant proteins, including enzymes, hormones and vaccines, have been efficiently expressed with intact biological activity. The expression of pharmaceutically proteins, using insect larvae or cocoons, has become very attractive. This review describes the use of insect larvae as an alternative to produce commercial recombinant proteins.

  20. Systemic Imidacloprid Affects Intraguild Parasitoids Differently

    Roe, R. Michael; Bacheler, Jack S.

    2015-01-01

    Toxoneuron nigriceps (Viereck) (Hymenoptera, Braconidae) and Campoletis sonorensis (Cameron) (Hymenoptera, Ichneumonidae) are solitary endoparasitoids of the tobacco budworm, Heliothis virescens (Fabricius) (Lepidoptera, Noctuidae). They provide biological control of H. virescens populations in Southeastern US agricultural production systems. Field and greenhouse experiments conducted from 2011–2014 compared parasitism rates of parasitoids that developed inside H. virescens larvae fed on tobacco plants treated with and without imidacloprid. The parasitoids in our study did not have a similar response. Toxoneuron nigriceps had reduced parasitism rates, but parasitism rates of C. sonorensis were unaffected. Preliminary data indicate that adult female lifespans of T. nigriceps are also reduced. ELISA was used to measure concentrations of neonicotinoids, imidacloprid and imidacloprid metabolites in H. virescens larvae that fed on imidacloprid-treated plants and in the parasitoids that fed on these larvae. Concentrations were detectable in the whole bodies of parasitized H. virescens larvae, T. nigriceps larvae and T. nigriceps adults, but not in C. sonorensis larvae and adults. These findings suggest that there are effects of imidacloprid on multiple trophic levels, and that insecticide use may differentially affect natural enemies with similar feeding niches. PMID:26658677

  1. Systemic Imidacloprid Affects Intraguild Parasitoids Differently.

    Sally V Taylor

    Full Text Available Toxoneuron nigriceps (Viereck (Hymenoptera, Braconidae and Campoletis sonorensis (Cameron (Hymenoptera, Ichneumonidae are solitary endoparasitoids of the tobacco budworm, Heliothis virescens (Fabricius (Lepidoptera, Noctuidae. They provide biological control of H. virescens populations in Southeastern US agricultural production systems. Field and greenhouse experiments conducted from 2011-2014 compared parasitism rates of parasitoids that developed inside H. virescens larvae fed on tobacco plants treated with and without imidacloprid. The parasitoids in our study did not have a similar response. Toxoneuron nigriceps had reduced parasitism rates, but parasitism rates of C. sonorensis were unaffected. Preliminary data indicate that adult female lifespans of T. nigriceps are also reduced. ELISA was used to measure concentrations of neonicotinoids, imidacloprid and imidacloprid metabolites in H. virescens larvae that fed on imidacloprid-treated plants and in the parasitoids that fed on these larvae. Concentrations were detectable in the whole bodies of parasitized H. virescens larvae, T. nigriceps larvae and T. nigriceps adults, but not in C. sonorensis larvae and adults. These findings suggest that there are effects of imidacloprid on multiple trophic levels, and that insecticide use may differentially affect natural enemies with similar feeding niches.

  2. Radiosensitivity of cultured insect cells: I. Lepidoptera

    Koval, T.M.

    1983-01-01

    The radiosensitivity of five lepidopteran insect cell lines representing five different genera has been investigated. These lines are: (1) TN-368, Trichoplusia ni; (2) IPLB-SF-1254, Spodoptera frugiperda; (3) IPLB-1075, Heliothis zea; (4) MRRL-CHl, clone GVl, Manduca sexta; and (5) IAL-PID2, Plodia interpunctella. The cell lines grew at different rates and had population doubling times that ranged from 19 to 52 hr. All of the lines are highly heteroploid and have approximate chromosome numbers near or above 100. The chromosomes are very small. All of the lines are extremely radioresistant; cell populations are able to recover from 260 kVp X-ray exposures up to and including 400 Gy, the highest dose examined. Cell survival curves were obtainable for only the TN-368 and IPLB-SF-1254 lines. The TN-368 cells displayed a biphasic survival response with D 0 , d/sub q/, and n values of 65.7 and 130.2 Gy, 9.0 and -36.1 Gy, and 1.2 and 0.8, respectively, for the steep and shallow portions of the curve. The IPLB-SF-1254 cells had a D 0 of 63.9 Gy. D/sub q/ of 19.0 Gy, and n value of 1.4. These studies provide definitive evidence of the radioresistance of lepidopteran cells, and suggest that this radioresistance is a characteristic of lepidopteran insects

  3. Relação entre toxicidade de proteínas Vip3Aa e sua capacidade de ligação a receptores intestinais de lepidópteros-praga

    Suzana Cristina Marucci

    2015-08-01

    Full Text Available Resumo:O objetivo deste trabalho foi avaliar a toxicidade de novas proteínas Vip3Aa e sua capacidade de ligação a vesículas de membrana da microvilosidade apical (VMMA do intestino de lagartas neonatas de Spodoptera frugiperda, Anticarsia gemmatalise Heliothis virescens. Proteínas expressas pelos genes vip3Aa42 e vip3Aa43 mostraram-se tóxicas a S. frugiperda (CL50 de 78,2 e 113 ng cm-2, respectivamente e A. gemmatalis(CL50 de 239,2 e 57,5 ng cm-2, respectivamente, e pouco tóxicas a H. virescens (CL50>5.000 ng cm-2. Os ensaios de ligação às VMMA mostraram que as proteínas unem-se de forma efetiva aos receptores nas vesículas das espécies avaliadas, mas essa capacidade de ligação somente é efetiva na ativação da toxicidade para as populações avaliadas de S. frugiperdae A. gemmatalis.

  4. Amtyr1: characterization of a gene from honeybee (Apis mellifera) brain encoding a functional tyramine receptor.

    Blenau, W; Balfanz, S; Baumann, A

    2000-03-01

    Biogenic amine receptors are involved in the regulation and modulation of various physiological and behavioral processes in both vertebrates and invertebrates. We have cloned a member of this gene family from the CNS of the honeybee, Apis mellifera. The deduced amino acid sequence is homologous to tyramine receptors cloned from Locusta migratoria and Drosophila melanogaster as well as to an octopamine receptor cloned from Heliothis virescens. Functional properties of the honeybee receptor were studied in stably transfected human embryonic kidney 293 cells. Tyramine reduced forskolin-induced cyclic AMP production in a dose-dependent manner with an EC50 of approximately 130 nM. A similar effect of tyramine was observed in membrane homogenates of honeybee brains. Octopamine also reduced cyclic AMP production in the transfected cell line but was both less potent (EC50 of approximately 3 microM) and less efficacious than tyramine. Receptor-encoding mRNA has a wide-spread distribution in the brain and subesophageal ganglion of the honeybee, suggesting that this tyramine receptor is involved in sensory signal processing as well as in higher-order brain functions.

  5. An ascovirus isolated from Spodoptera litura (Noctuidae: Lepidoptera) transmitted by the generalist endoparasitoid Meteorus pulchricornis (Braconidae: Hymenoptera).

    Arai, Eiko; Ishii, Kazuo; Ishii, Hiroki; Sagawa, Shiori; Makiyama, Nao; Mizutani, Tetsuya; Omatsu, Tsutomu; Katayama, Yukie; Kunimi, Yasuhisa; Inoue, Maki N; Nakai, Madoka

    2018-04-01

    The family Ascoviridae is a recently described virus family whose members are transmitted by parasitoids and cause chronic and lethal infections in lepidopteran insects. Little is known about the biology and ecology of ascoviruses, and few isolates have been found outside the United States. We report here the isolation of a new ascovirus variant from Spodoptera litura in Japan. Full genome sequence and phylogenetic analyses showed that this virus was closely related to variants in Heliothis virescens ascovirus-3a, and it was named HvAV-3j. HvAV-3j has a DNA genome of 191 718 bp, with 189 putative ORFs and a GC content of 45.6 %, and is highly similar to HvAV-3h, which was isolated in China. In a field survey, the endoparasitoid Meteorus pulchricornis caused a high percentage of parasitization in populations of S. litura larvae, and under laboratory conditions M. pulchricornis was able to transmit HvAV-3j from infected to uninfected larvae by oviposition. Meteorus pulchricornis is thus likely to be a major vector for HvAV-3j transmission in Japan. This species is recognized here for the first time as a vector of ascoviruses that parasitizes a range of host species that extends across families.

  6. Duration of plant damage by host larvae affects attraction of two parasitoid species (Microplitis croceipes and Cotesia marginiventris) to cotton: implications for interspecific competition.

    Morawo, Tolulope; Fadamiro, Henry

    2014-12-01

    Volatile organic compounds (VOCs) released by herbivore-damaged plants can guide parasitoids to their hosts. The quantity and quality of VOC blends emitted by plants may be affected by the duration of plant damage by herbivores, which could have potential ramifications on the recruitment of competing parasitoids. We used two parasitoid species, Microplitis croceipes and Cotesia marginiventris (Hymenoptera: Braconidae), to address the question of whether duration of plant damage affects parasitoid use of plant VOCs for host location. Both wasp species are larval endoparasitoids of Heliothis virescens (Lepidoptera: Noctuidae), an important pest of cotton. Attraction of the two parasitoid species to odors emitted by undamaged (UD), fresh (6 h infestation) damage (FD), and old (24 h infestation) damage (OD) cotton plants infested by H. virescens larvae was investigated using a headspace volatile collection system coupled with four-choice olfactometer bioassay. Both sexes of M. croceipes showed a preference for FD- and OD-plant odors over UD-plants. On the other hand, more C. marginiventris females were attracted to UD- and FD-plants than to OD-plants. GC/MS analyses showed qualitative and quantitative differences in the VOC profiles of UD, FD, and OD-plants, which may explain the observed preferences of the parasitoids. These results suggest a temporal partitioning in the recruitment of M. croceipes and C. marginiventris to H. virescens-damaged cotton, and may have potential implications for interspecific competition between the two parasitoid species.

  7. Biologia do ectoparasitóide Bracon hebetor Say, 1857 (Hymenoptera: Braconidae em sete espécies de lepidópteros Biology of the ectoparasitoid Bracon hebetor Say, 1857 (Hymenoptera: Braconidae on seven lepidopteran species

    Sandra Regina Magro

    2001-12-01

    Full Text Available Bracon hebetor Say, 1857 é um ectoparasitóide larval de várias espécies de piralídeos que atacam grãos armazenados, sendo considerado um agente potencial de controle biológico dessas pragas. Assim, a biologia de B. hebetor foi estudada em condições controladas de temperatura (25 ± 2°C, umidade relativa (60 ± 10% e fotoperíodo (fotofase de 14 horas, sobre sete espécies de lepidópteros, Anagasta kuehniella (Zeller, Corcyra cephalonica Stainton e Sitotroga cerealella (Olivier (hospedeiros naturais e Diatraea saccharalis (Fabricius, Heliothis virescens (Fabricius, Anticarsia gemmatalis Hübner, Spodoptera frugiperda (J.E. Smith (insetos criados rotineiramente no laboratório de Biologia de Insetos da ESALQ/USP, para determinar o melhor hospedeiro para sua criação em laboratório. A duração e a viabilidade do ciclo biológico (ovo-adulto foram afetadas, dependendo do hospedeiro utilizado. A. kuehniella e C. cephalonica foram hospedeiros semelhantes para a criação de B. hebetor, produzindo insetos com duração de ciclo de 12,8 dias, viabilidade em torno de 90% e ótima capacidade de paralisação e parasitismo. D. saccharalis foi o único hospedeiro não natural que proporcionou resultados semelhantes àqueles obtidos sobre as três traças hospedeiras naturais. Quanto à agressividade, D. saccharalis produziu insetos com capacidade de paralisação e parasitismo semelhantes àqueles criados sobre as traças S. cerealella e C. cephalonica.Bracon hebetor Say, 1857 is a larval ectoparasitoid of several species of pyralids which attack stored grains, therefore a potential biological control agent of these pests. To determine the best host for laboratory rearing, the biology of B. hebetor was studied under controlled temperature conditions (25 ± 2°C, relative humidity (60 ± 10% and photoperiod (14-hour photophase on seven lepidopteran larvae: natural hosts Anagasta kuehniella (Zeller, Corcyra cephalonica Stainton and Sitotroga

  8. Use of backscattered electron imaging, X-ray microanalysis and X-ray microscopy in demonstrating physiological cell death

    Bowen, I.D.; Worrill, N.A.; Winters, C.A.; Mullarkey, K.

    1988-01-01

    The cytochemical localization of enzymatic activity by means of backscattered electron imaging (BEI) is reviewed and the application of BEI to changes in acid phosphatase and ATPase distribution during physiological (programmed) cell death in Heliothis midgut is explored. Programmed cell death entails the release of nascent free acid phosphatase as extracisternal hydrolase. This shift can readily be detected by means of the atomic number contrast imparted by BEI of the lead phosphatase reaction product, thus enabling the distribution of dying cells to be mapped. BEI is particularly useful in this context as it allows the examination of bulk specimens at low magnification. Death of cells is also accompanied by a collapse in ATPase activity which shows up as cytochemically negative areas in the X-ray microscope and by means of BEI. Acid phosphatase in normal cells is localized in the apical microvilli and lysosomes. Senescent or dying cells, however, clearly show a basally situated free hydrolase which migrates throughout the cell. Parallel TEM results confirm that this enzyme is ribosomal and extracisternal rather than lysosomal in origin. ATPase activity is largely limited to the apical microvilli, although there is some activity associated with the basal plasma membranes. The apical ATPase, however is partially resistant to ouabain. Young and mature cells are positive although in the latter case some microvilli may be lost as the cells acquire a negative cap or dome. Inhibition by bromotetramizole indicates that apical activity is not to any significant extent contributed to by alkaline phosphatase. Degenerate or dead cells are negative and can be seen as a mozaic of black patches among normal cells when imaged by means of BEI or X-ray microscopy

  9. Optimal Cotton Insecticide Application Termination Timing: A Meta-Analysis.

    Griffin, T W; Zapata, S D

    2016-08-01

    The concept of insecticide termination timing is generally accepted among cotton (Gossypium hirsutum) researchers; however, exact timings are often disputed. Specifically, there is uncertainty regarding the last economic insecticide application to control fruit-feeding pests including tarnished plant bug (Lygus lineolaris (Palisot de Beauvois)), boll weevil (Anthonomus grandis), bollworm (Helicoverpa zea), tobacco budworm (Heliothis virescens), and cotton fleahopper (Pseudatomoscelis seriatus). A systematic review of prior studies was conducted within a meta-analytic framework. Nine publicly available articles were amalgamated to develop an optimal timing principle. These prior studies reported 53 independent multiple means comparison field experiments for a total of 247 trial observations. Stochastic plateau theory integrated with econometric meta-analysis methodology was applied to the meta-database to determine the shape of the functional form of both the agronomic optimal insecticide termination timing and corresponding yield potential. Results indicated that current university insecticide termination timing recommendations are later than overall estimated timing suggested. The estimated 159 heat units (HU) after the fifth position above white flower (NAWF5) was found to be statistically different than the 194 HU termination used as the status quo recommended termination timing. Insecticides applied after 159 HU may have been applied in excess, resulting in unnecessary economic and environmental costs. Empirical results also suggested that extending the insecticide termination time by one unit resulted in a cotton lint yield increase of 0.27 kilograms per hectare up to the timing where the plateau began. Based on economic analyses, profit-maximizing producers may cease application as soon as 124 HU after NAWF5. These results provided insights useful to improve production systems by applying inputs only when benefits were expected to be in excess of the

  10. Comparative evaluation of phenoloxidase activity in different larval stages of four lepidopteran pests after exposure to Bacillus thuringiensis.

    Valadez-Lira, J A; Alcocer-Gonzalez, J M; Damas, G; Nuñez-Mejía, G; Oppert, B; Rodriguez-Padilla, C; Tamez-Guerra, P

    2012-01-01

    Microbial entomopathogen-based bioinsecticides are recognized as alternatives to synthetic pesticides. Insects defend themselves against microbial pathogens by innate mechanisms, including increased phenoloxidase (PO) activity, but its relationship with microbial bioinsecticides efficacy is little known. This study evaluated the differences in PO activity at different developmental stages of the tobacco budworm Heliothis virescens Fabricius (Lepidoptera: Noctuidae), Indian meal moth Plodia interpunctella (Hübner) (Pyralidae), beet armyworm Spodoptera exigua (Hübner) (Noctuidae), and cabbage looper Trichoplusia ni (Hübner) (Noctuidae). Additionally, 2(nd)- and 4(th)-instars were exposed to the LC(50) value of the commercial Bacillus thuringiensis (Bt) spray, Biobit(®). The percentage of insecticidal activity (IA%) on 2(nd)-instar Biobit-exposed larvae was approximately the predicted 50 % mortality for all species except S. exigua. With all 4(th) instar Biobit-exposed larvae, mortality was not significantly different from that of unexposed larvae. Unexposed insects had a significantly higher PO activity in pre-pupae and pupae than early-instar larvae and adults, whereas PO activity was higher in adult females than in males. Correlation analysis between IA% and PO activity revealed significant r-values (p < 0.01) in 2(nd) instar H. virescens (r = 0.979) and P. interpunctella (r = 0.930). Second instar Biobit-exposed P. interpunctella had 10 times more PO activity than unexposed larvae. Similarly, the amount of total protein was lower in 4(th) instar Biobit-exposed H. virescens and higher in S. exigua. Therefore, the results indicated a relationship between Biobit susceptibility and PO activity in some cases. This information may be useful if the Biobit application period is timed for a developmental stage with low PO activity. However, more studies are needed to determine the correlation of each insect with a particular bioinsecticide.

  11. Comparison of field-collected ascovirus isolates by DNA hybridization, host range, and histopathology.

    Hamm, J J; Styer, E L; Federici, B A

    1998-09-01

    Six field-collected ascovirus isolates obtained from five noctuid species in the continental United States were compared with respect to the general relatedness of their DNA, host range, and histopathology. Two isolates were from Spodoptera frugiperda, and the other four were from Autographa precationis, Heliothis virescens, Helicoverpa zea, and Trichoplusia ni. DNA-DNA hybridization studies showed that the six isolates belonged to three distinct viral species, with the isolates from S. frugiperda composing one species, those from A. precationis and H. virescens a second species, and those from H. zea and T. ni a third species. The host range and histopathology of each isolate was studied in eight noctuid species, S. frugiperda, Spodoptera ornithogalli, Spodoptera exigua, Spodoptera eridania, H. virescens, H. zea, A. precationis, and Feltia subterranea. Though some variation existed between the different isolates of each viral species, distinct patterns were apparent for each. The viral species from S. frugiperda had a host range that was limited primarily to Spodoptera species and both isolates of this virus only replicated and caused significant pathology in the fat body, whereas the viral species from A. precationis and H. virescens had a much broader host range that included most of the species tested, but also had a tissue tropism primarily restricted to the fat body. The viral species from T. ni and H. zea readily infected all the hosts tested, where the principal site of replication and significant pathology was the epidermis. In many test hosts, however, this viral species also replicated and caused significant pathology in the tracheal epithelium and to a lesser extent in the fat body. Aside from contributing to knowledge of ascovirus biology, these studies indicate that DNA hybridization profiles combined with studies of host range and tissue tropism can be used as characters for defining ascovirus species. Copyright 1998 Academic Press.

  12. Representation of pheromones, interspecific signals, and plant odors in higher olfactory centers; mapping physiologically identified antennal-lobe projection neurons in the male heliothine moth

    Xin-Cheng eZhao

    2014-10-01

    Full Text Available In the primary olfactory centre of the moth brain, for example, a few enlarged glomeruli situated dorsally, at the entrance of the antennal nerve, are devoted to information about female-produced substances whereas a set of more numerous ordinary glomeruli receives input about general odorants. Heliothine moths are particularly suitable for studying central chemosensory mechanisms not only because of their anatomically separated systems for plant odours and pheromones but also due to their use of female-produced substances in communication across the species. Thus, the male-specific system of heliothine moths includes two sub arrangements, one ensuring attraction and mating behavior by carrying information about pheromones released by conspecifics, and the other reproductive isolation via signal information emitted from heterospecifics. Based on previous tracing experiments, a general chemotopic organization of the male-specific glomeruli has been demonstrated in a number of heliothine species. As compared to the well explored organization of the moth antennal lobe, demonstrating a non-overlapping representation of the biologically relevant stimuli, less is known about the neural arrangement residing at the following synaptic level, i.e. the mushroom body calyces and the lateral horn. In the study presented here, we have labelled physiologically characterized antennal-lobe projection neurons in males of the two heliothine species, Heliothis virescens and Helicoverpa assulta, for the purpose of mapping their target regions in the protocerebrum. In order to compare the representation of plant odours, pheromones, and interspecific signals in the higher brain regions of each species, we have created standard brain atlases and registered three-dimensional models of distinct uniglomerular projection neuron types into the relevant atlas.

  13. An ABC transporter mutation is correlated with insect resistance to Bacillus thuringiensis Cry1Ac toxin.

    Linda J Gahan

    2010-12-01

    Full Text Available Transgenic crops producing insecticidal toxins from Bacillus thuringiensis (Bt are commercially successful in reducing pest damage, yet knowledge of resistance mechanisms that threaten their sustainability is incomplete. Insect resistance to the pore-forming Cry1Ac toxin is correlated with the loss of high-affinity, irreversible binding to the mid-gut membrane, but the genetic factors responsible for this change have been elusive. Mutations in a 12-cadherin-domain protein confer some Cry1Ac resistance but do not block this toxin binding in in vitro assays. We sought to identify mutations in other genes that might be responsible for the loss of binding. We employed a map-based cloning approach using a series of backcrosses with 1,060 progeny to identify a resistance gene in the cotton pest Heliothis virescens that segregated independently from the cadherin mutation. We found an inactivating mutation of the ABC transporter ABCC2 that is genetically linked to Cry1Ac resistance and is correlated with loss of Cry1Ac binding to membrane vesicles. ABC proteins are integral membrane proteins with many functions, including export of toxic molecules from the cell, but have not been implicated in the mode of action of Bt toxins before. The reduction in toxin binding due to the inactivating mutation suggests that ABCC2 is involved in membrane integration of the toxin pore. Our findings suggest that ABC proteins may play a key role in the mode of action of Bt toxins and that ABC protein mutations can confer high levels of resistance that could threaten the continued utilization of Bt-expressing crops. However, such mutations may impose a physiological cost on resistant insects, by reducing export of other toxins such as plant secondary compounds from the cell. This weakness could be exploited to manage this mechanism of Bt resistance in the field.

  14. An ABC transporter mutation is correlated with insect resistance to Bacillus thuringiensis Cry1Ac toxin.

    Gahan, Linda J; Pauchet, Yannick; Vogel, Heiko; Heckel, David G

    2010-12-16

    Transgenic crops producing insecticidal toxins from Bacillus thuringiensis (Bt) are commercially successful in reducing pest damage, yet knowledge of resistance mechanisms that threaten their sustainability is incomplete. Insect resistance to the pore-forming Cry1Ac toxin is correlated with the loss of high-affinity, irreversible binding to the mid-gut membrane, but the genetic factors responsible for this change have been elusive. Mutations in a 12-cadherin-domain protein confer some Cry1Ac resistance but do not block this toxin binding in in vitro assays. We sought to identify mutations in other genes that might be responsible for the loss of binding. We employed a map-based cloning approach using a series of backcrosses with 1,060 progeny to identify a resistance gene in the cotton pest Heliothis virescens that segregated independently from the cadherin mutation. We found an inactivating mutation of the ABC transporter ABCC2 that is genetically linked to Cry1Ac resistance and is correlated with loss of Cry1Ac binding to membrane vesicles. ABC proteins are integral membrane proteins with many functions, including export of toxic molecules from the cell, but have not been implicated in the mode of action of Bt toxins before. The reduction in toxin binding due to the inactivating mutation suggests that ABCC2 is involved in membrane integration of the toxin pore. Our findings suggest that ABC proteins may play a key role in the mode of action of Bt toxins and that ABC protein mutations can confer high levels of resistance that could threaten the continued utilization of Bt-expressing crops. However, such mutations may impose a physiological cost on resistant insects, by reducing export of other toxins such as plant secondary compounds from the cell. This weakness could be exploited to manage this mechanism of Bt resistance in the field.

  15. Pest protection conferred by a Beta vulgaris serine proteinase inhibitor gene.

    Ann C Smigocki

    Full Text Available Proteinase inhibitors provide a means of engineering plant resistance to insect pests. A Beta vulgaris serine proteinase inhibitor gene (BvSTI was fused to the constitutive CaMV35S promoter for over-expression in Nicotiana benthamiana plants to study its effect on lepidopteran insect pests. Independently derived BvSTI transgenic tobacco T2 homozygous progeny were shown to have relatively high BvSTI gene transcript levels. BvSTI-specific polyclonal antibodies cross-reacted with the expected 30 kDA recombinant BvSTI protein on Western blots. In gel trypsin inhibitor activity assays revealed a major clear zone that corresponded to the BvSTI proteinase inhibitor that was not detected in the untransformed control plants. BvSTI-transgenic plants were bioassayed for resistance to five lepidopteran insect pests. Spodoptera frugiperda, S. exigua and Manduca sexta larvae fed BvSTI leaves had significant reductions in larval weights as compared to larvae fed on untransformed leaves. In contrast, larval weights increased relative to the controls when Heliothis virescens and Agrotis ipsilon larvae were fed on BvSTI leaves. As the larvae entered the pupal stage, pupal sizes reflected the overall larval weights. Some developmental abnormalities of the pupae and emerging moths were noted. These findings suggest that the sugar beet BvSTI gene may prove useful for effective control of several different lepidopteran insect pests in genetically modified tobacco and other plants. The sugar beet serine proteinase inhibitor may be more effective for insect control because sugar beet is cropped in restricted geographical areas thus limiting the exposure of the insects to sugar beet proteinase inhibitors and build up of non-sensitive midgut proteases.

  16. Moth sex pheromone receptors and deceitful parapheromones.

    Pingxi Xu

    Full Text Available The insect's olfactory system is so selective that male moths, for example, can discriminate female-produced sex pheromones from compounds with minimal structural modifications. Yet, there is an exception for this "lock-and-key" tight selectivity. Formate analogs can be used as replacement for less chemically stable, long-chain aldehyde pheromones, because male moths respond physiologically and behaviorally to these parapheromones. However, it remained hitherto unknown how formate analogs interact with aldehyde-sensitive odorant receptors (ORs. Neuronal responses to semiochemicals were investigated with single sensillum recordings. Odorant receptors (ORs were cloned using degenerate primers, and tested with the Xenopus oocyte expression system. Quality, relative quantity, and purity of samples were evaluated by gas chromatography and gas chromatography-mass spectrometry. We identified olfactory receptor neurons (ORNs housed in trichoid sensilla on the antennae of male navel orangeworm that responded equally to the main constituent of the sex pheromone, (11Z,13Z-hexadecadienal (Z11Z13-16Ald, and its formate analog, (9Z,11Z-tetradecen-1-yl formate (Z9Z11-14OFor. We cloned an odorant receptor co-receptor (Orco and aldehyde-sensitive ORs from the navel orangeworm, one of which (AtraOR1 was expressed specifically in male antennae. AtraOR1•AtraOrco-expressing oocytes responded mainly to Z11Z13-16Ald, with moderate sensitivity to another component of the sex pheromone, (11Z,13Z-hexadecadien-1-ol. Surprisingly, this receptor was more sensitive to the related formate than to the natural sex pheromone. A pheromone receptor from Heliothis virescens, HR13 ( = HvirOR13 showed a similar profile, with stronger responses elicited by a formate analog than to the natural sex pheromone, (11Z-hexadecenal thus suggesting this might be a common feature of moth pheromone receptors.

  17. Identification of receptors of main sex-pheromone components of three Lepidopteran species.

    Mitsuno, Hidefumi; Sakurai, Takeshi; Murai, Masatoshi; Yasuda, Tetsuya; Kugimiya, Soichi; Ozawa, Rika; Toyohara, Haruhiko; Takabayashi, Junji; Miyoshi, Hideto; Nishioka, Takaaki

    2008-09-01

    Male moths discriminate conspecific female-emitted sex pheromones. Although the chemical components of sex pheromones have been identified in more than 500 moth species, only three components in Bombyx mori and Heliothis virescens have had their receptors identified. Here we report the identification of receptors for the main sex-pheromone components in three moth species, Plutella xylostella, Mythimna separata and Diaphania indica. We cloned putative sex-pheromone receptor genes PxOR1, MsOR1 and DiOR1 from P. xylostella, M. separata and D. indica, respectively. Each of the three genes was exclusively expressed with an Or83b orthologous gene in male olfactory receptor neurons (ORNs) that are surrounded by supporting cells expressing pheromone-binding-protein (PBP) genes. By two-electrode voltage-clamp recording, we tested the ligand specificity of Xenopus oocytes co-expressing PxOR1, MsOR1 or DiOR1 with an OR83b family protein. Among the seven sex-pheromone components of the three moth species, the oocytes dose-dependently responded only to the main sex-pheromone component of the corresponding moth species. In our study, PBPs were not essential for ligand specificity of the receptors. On the phylogenetic tree of insect olfactory receptors, the six sex-pheromone receptors identified in the present and previous studies are grouped in the same subfamily but have no relation with the taxonomy of moths. It is most likely that sex-pheromone receptors have randomly evolved from ancestral sex-pheromone receptors before the speciation of moths and that their ligand specificity was modified by mutations of local amino acid sequences after speciation.

  18. Molecular evolution of the odorant and gustatory receptor genes in lepidopteran insects: implications for their adaptation and speciation.

    Engsontia, Patamarerk; Sangket, Unitsa; Chotigeat, Wilaiwan; Satasook, Chutamas

    2014-08-01

    Lepidoptera (comprised of butterflies and moths) is one of the largest groups of insects, including more than 160,000 described species. Chemoreception plays important roles in the adaptation of these species to a wide range of niches, e.g., plant hosts, egg-laying sites, and mates. This study investigated the molecular evolution of the lepidopteran odorant (Or) and gustatory receptor (Gr) genes using recently identified genes from Bombyx mori, Danaus plexippus, Heliconius melpomene, Plutella xylostella, Heliothis virescens, Manduca sexta, Cydia pomonella, and Spodoptera littoralis. A limited number of cases of large lineage-specific gene expansion are observed (except in the P. xylostella lineage), possibly due to selection against tandem gene duplication. There has been strong purifying selection during the evolution of both lepidopteran odorant and gustatory genes, as shown by the low ω values estimated through CodeML analysis, ranging from 0.0093 to 0.3926. However, purifying selection has been relaxed on some amino acid sites in these receptors, leading to sequence divergence, which is a precursor of positive selection on these sequences. Signatures of positive selection were detected only in a few loci from the lineage-specific analysis. Estimation of gene gains and losses suggests that the common ancestor of the Lepidoptera had fewer Or genes compared to extant species and an even more reduced number of Gr genes, particularly within the bitter receptor clade. Multiple gene gains and a few gene losses occurred during the evolution of Lepidoptera. Gene family expansion may be associated with the adaptation of lepidopteran species to plant hosts, especially after angiosperm radiation. Phylogenetic analysis of the moth sex pheromone receptor genes suggested that chromosomal translocations have occurred several times. New sex pheromone receptors have arisen through tandem gene duplication. Positive selection was detected at some amino acid sites predicted to be

  19. Sex-linked pheromone receptor genes of the European corn borer, Ostrinia nubilalis, are in tandem arrays.

    Yuji Yasukochi

    Full Text Available BACKGROUND: Tuning of the olfactory system of male moths to conspecific female sex pheromones is crucial for correct species recognition; however, little is known about the genetic changes that drive speciation in this system. Moths of the genus Ostrinia are good models to elucidate this question, since significant differences in pheromone blends are observed within and among species. Odorant receptors (ORs play a critical role in recognition of female sex pheromones; eight types of OR genes expressed in male antennae were previously reported in Ostrinia moths. METHODOLOGY/PRINCIPAL FINDINGS: We screened an O. nubilalis bacterial artificial chromosome (BAC library by PCR, and constructed three contigs from isolated clones containing the reported OR genes. Fluorescence in situ hybridization (FISH analysis using these clones as probes demonstrated that the largest contig, which contained eight OR genes, was located on the Z chromosome; two others harboring two and one OR genes were found on two autosomes. Sequence determination of BAC clones revealed the Z-linked OR genes were closely related and tandemly arrayed; moreover, four of them shared 181-bp direct repeats spanning exon 7 and intron 7. CONCLUSIONS/SIGNIFICANCE: This is the first report of tandemly arrayed sex pheromone receptor genes in Lepidoptera. The localization of an OR gene cluster on the Z chromosome agrees with previous findings for a Z-linked locus responsible for O. nubilalis male behavioral response to sex pheromone. The 181-bp direct repeats might enhance gene duplications by unequal crossovers. An autosomal locus responsible for male response to sex pheromone in Heliothis virescens and H. subflexa was recently reported to contain at least four OR genes. Taken together, these findings support the hypothesis that generation of additional copies of OR genes can increase the potential for male moths to acquire altered specificity for pheromone components, and accordingly

  20. Agonist-mediated activation of Bombyx mori diapause hormone receptor signals to extracellular signal-regulated kinases 1 and 2 through Gq-PLC-PKC-dependent cascade.

    Jiang, Xue; Yang, Jingwen; Shen, Zhangfei; Chen, Yajie; Shi, Liangen; Zhou, Naiming

    2016-08-01

    Diapause is a developmental strategy adopted by insects to survive in challenging environments such as the low temperatures of a winter. This unique process is regulated by diapause hormone (DH), which is a neuropeptide hormone that induces egg diapause in Bombyx mori and is involved in terminating pupal diapause in heliothis moths. An G protein-coupled receptor from the silkworm, B. mori, has been identified as a specific cell surface receptor for DH. However, the detailed information on the DH-DHR system and its mechanism(s) involved in the induction of embryonic diapause remains unknown. Here, we combined functional assays with various specific inhibitors to elucidate the DHR-mediated signaling pathways. Upon activation by DH, B. mori DHR is coupled to the Gq protein, leading to a significant increase of intracellular Ca(2+) and cAMP response element-driven luciferase activity in an UBO-QIC, a specific Gq inhibitor, sensitive manner. B. mori DHR elicited ERK1/2 phosphorylation in a dose- and time-dependent manner in response to DH. This effect was almost completely inhibited by co-incubation with UBO-QIC and was also significantly suppressed by PLC inhibitor U73122, PKC inhibitors Gö6983 and the Ca(2+) chelator EGTA. Moreover, DHR-induced activation of ERK1/2 was significantly attenuated by treatment with the Gβγ specific inhibitors gallein and M119K and the PI3K specific inhibitor Wortmannin, but not by the Src specific inhibitor PP2. Our data also demonstrates that the EGFR-transactivation pathway is not involved in the DHR-mediated ERK1/2 phosphorylation. Future efforts are needed to clarify the role of the ERK1/2 signaling pathway in the DH-mediated induction of B. mori embryonic diapause. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Monoclonal Antibody Analysis and Insecticidal Spectrum of Three Types of Lepidopteran-Specific Insecticidal Crystal Proteins of Bacillus thuringiensis

    Höfte, Herman; Van Rie, Jeroen; Jansens, Stefan; Van Houtven, Annemie; Vanderbruggen, Hilde; Vaeck, Mark

    1988-01-01

    We have investigated the protein composition and the insecticidal spectrum of crystals of 29 Bacillus thuringiensis strains active against lepidopteran larvae. All crystals contained proteins of 130 to 140 kilodaltons (kDa) which could be grouped into three types by the molecular weight of the protoxin and the trypsin-activated core fragment. Proteins of the three types showed a characteristic insecticidal spectrum when tested against five lepidopteran species. Type A crystal proteins were protoxins of 130 or 133 kDa, which were processed into 60-kDa toxins by trypsin. Several genes encoding crystal proteins of this type have been cloned and sequenced earlier. They are highly conserved in the N-terminal half of the toxic fragment and were previously classified in three subtypes (the 4.5-, 5.3-, and 6.6-kilobase subtypes) based on the restriction map of their genes. The present study shows that different proteins of these three subtypes were equally toxic against Manduca sexta and Pieris brassicae and had no detectable activity against Spodoptera littoralis. However, the 4.5-, 5.3-, and 6.6-kilobase subtypes differed in their toxicity against Heliothis virescens and Mamestra brassicae. Type B crystal proteins consisted of 140-kDa protoxins with a 55-kDa tryptic core fragment. These were only active against one of the five insect species tested (P. brassicae). The protoxin and the trypsin-activated toxin of type C were 135- and 63-kDa proteins, respectively. Proteins of this type were associated with high toxicity against S. littoralis and M. brassicae. A panel of 35 monoclonal antibodies was used to compare the structural characteristics of crystal proteins of the three different types and subtypes. Each type of protein could be associated with a typical epitope structure, indicating an unambiguous correlation between antigenic structure and insect specificity. Images PMID:16347711

  2. The role of herbivore- and plant-related experiences in intraspecific host preference of a relatively specialized parasitoid.

    Morawo, Tolulope; Fadamiro, Henry

    2017-09-06

    Parasitoids use odor cues from infested plants and herbivore hosts to locate their hosts. Specialist parasitoids of generalist herbivores are predicted to rely more on herbivore-derived cues than plant-derived cues. Microplitis croceipes (Cresson) (Hymenoptera: Braconidae) is a relatively specialized larval endoparasitoid of Heliothis virescens (F.) (Lepidoptera: Noctuidae), which is a generalist herbivore on several crops including cotton and soybean. Using M. croceipes/H. virescens as a model system, we tested the following predictions about specialist parasitoids of generalist herbivores: (i) naive parasitoids will show innate responses to herbivore-emitted kairomones, regardless of host plant identity and (ii) herbivore-related experience will have a greater influence on intraspecific oviposition preference than plant-related experience. Inexperienced (naive) female M. croceipes did not discriminate between cotton-fed and soybean-fed H. virescens in oviposition choice tests, supporting our first prediction. Oviposition experience alone with either host group influenced subsequent oviposition preference while experience with infested plants alone did not elicit preference in M. croceipes, supporting our second prediction. Furthermore, associative learning of oviposition with host-damaged plants facilitated host location. Interestingly, naive parasitoids attacked more soybean-fed than cotton-fed host larvae in two-choice tests when a background of host-infested cotton odor was supplied, and vice versa. This suggests that plant volatiles may have created an olfactory contrast effect. We discussed ecological significance of the results and concluded that both plant- and herbivore-related experiences play important role in parasitoid host foraging. © 2017 Institute of Zoology, Chinese Academy of Sciences.

  3. Nudiviruses and other large, double-stranded circular DNA viruses of invertebrates: new insights on an old topic.

    Wang, Yongjie; Jehle, Johannes A

    2009-07-01

    Nudiviruses (NVs) are a highly diverse group of large, circular dsDNA viruses pathogenic for invertebrates. They have rod-shaped and enveloped nucleocapsids, replicate in the nucleus of infected host cells, and possess interesting biological and molecular properties. The unassigned viral genus Nudivirus has been proposed for classification of nudiviruses. Currently, the nudiviruses comprise five different viruses: the palm rhinoceros beetle virus (Oryctes rhinoceros NV, OrNV), the Hz-1 virus (Heliothis zea NV-1, HzNV-1), the cricket virus (Gryllus bimaculatus NV, GbNV), the corn earworm moth Hz-2 virus (HzNV-2), and the occluded shrimp Monodon Baculovirus reassigned as Penaeus monodon NV (PmNV). Thus far, the genomes of OrNV, GbNV, HzNV-1 and HzNV-2 have been completely sequenced. They vary between 97 and 230kbp in size and encode between 98 and 160 open reading frames (ORFs). All sequenced nudiviruses have 33 ORFs in common. Strikingly, 20 of them are homologous to baculovirus core genes involved in RNA transcription, DNA replication, virion structural components and other functions. Another nine conserved ORFs are likely associated with DNA replication, repair and recombination, and nucleotide metabolism; one is homologous to baculovirus iap-3 gene; two are nudivirus-specific ORFs of unknown function. Interestingly, one nudivirus ORF is similar to polh/gran gene, encoding occlusion body protein matrix and being conserved in Alpha- Beta- and Gammabaculoviruses. Members of nudiviruses are closely related and form a monophyletic group consisting of two sister clades of OrNV/GbNV and HzNVs/PmNV. It is proposed that nudiviruses and baculoviruses derived from a common ancestor and are evolutionarily related to other large DNA viruses such as the insect-specific salivary gland hypertrophy virus (SGHV) and the marine white spot syndrome virus (WSSV).

  4. Enhanced methanol production in plants provides broad spectrum insect resistance.

    Sameer Dixit

    Full Text Available Plants naturally emit methanol as volatile organic compound. Methanol is toxic to insect pests; but the quantity produced by most of the plants is not enough to protect them against invading insect pests. In the present study, we demonstrated that the over-expression of pectin methylesterase, derived from Arabidopsis thaliana and Aspergillus niger, in transgenic tobacco plants enhances methanol production and resistance to polyphagous insect pests. Methanol content in the leaves of transgenic plants was measured using proton nuclear spectroscopy (1H NMR and spectra showed up to 16 fold higher methanol as compared to control wild type (WT plants. A maximum of 100 and 85% mortality in chewing insects Helicoverpa armigera and Spodoptera litura larvae was observed, respectively when fed on transgenic plants leaves. The surviving larvae showed less feeding, severe growth retardation and could not develop into pupae. In-planta bioassay on transgenic lines showed up to 99 and 75% reduction in the population multiplication of plant sap sucking pests Myzus persicae (aphid and Bemisia tabaci (whitefly, respectively. Most of the phenotypic characters of transgenic plants were similar to WT plants. Confocal microscopy showed no deformities in cellular integrity, structure and density of stomata and trichomes of transgenic plants compared to WT. Pollen germination and tube formation was also not affected in transgenic plants. Cell wall enzyme transcript levels were comparable with WT. This study demonstrated for the first time that methanol emission can be utilized for imparting broad range insect resistance in plants.

  5. Developing Cotton IPM by Conserving Parasitoids and Predators of The Main Pest

    Nurindah Nurindah

    2015-09-01

    Full Text Available On early development of intensive cotton program, insect pests were considered as an important aspect in cotton cultivation, so that it needed to be scheduled sprays. The frequency of sprays was 7 times used 12L of chemical insecticides per hectare per season. Development of cotton IPM was emphasized on non-chemical control methods through optimally utilize natural enemies of the cotton main pests (Amrasca biguttulla (IshidaHelicoverpa armigera (Hübner. Conservation of parasitoids and predators by providing the environment that support their population development is an act of supporting the natural enemies as an effective biotic mortality factor of the insect pests. The conservation could be done by improving the plant matter and cultivation techniques that include the use of resistant variety to leafhopper, intercropping cotton with secondary food plants, mulch utilization, using action threshold that considered the presence of natural enemies, and application of botanical insecticides, if needed. Conservation of parasitoids and predators in cotton IPM could control the insect pests without any insecticide spray in obtaining the production of cotton seed. As such, the use of IPM method would increase farmers’ income.

  6. Intraguild interactions and behavior of Spodoptera frugiperda and Helicoverpa spp. on maize.

    Bentivenha, José Pf; Montezano, Débora G; Hunt, Thomas E; Baldin, Edson Ll; Peterson, Julie A; Victor, Vinícius S; Pannuti, Luiz Er; Vélez, Ana M; Paula-Moraes, Silvana V

    2017-11-01

    Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is one of the major pests of maize and is in the same feeding guild as the noctuid pests Helicoverpa zea (Boddie) and Helicoverpa armigera (Hübner), recently reported in South and North America. The intraguild interactions of these species were assessed in laboratory and field conditions by determining the survival of larvae in interaction scenarios with non-Bt maize silks and ears. Moreover, a video tracking system was utilized to evaluate behavioral parameters during larval interactions in scenarios with or without food. In intraguild interactions, S. frugiperda had greater survival (55-100%) when competing with Helicoverpa spp. in scenarios where larvae were the same instar or when they were larger (fourth versus second) than their competitor. Frequency and time in food of S. frugiperda larvae were negatively influenced by interactions. Larvae of S. frugiperda moved shorter distances (less than 183.03 cm) compared with H. zea. Overall, S. frugiperda had a competitive advantage over Helicoverpa spp. This study provides significant information regarding noctuid behavior and larval survival during intraguild interactions, which may impact pest prevalence and population dynamics, thereby affecting integrated pest management and insect resistance management of these species in maize. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  7. Mass rearing and augmentative biological control evaluation of Rhynocoris fuscipes (Hemiptera: Reduviidae) against multiple pests of cotton.

    Tomson, Majesh; Sahayaraj, Kitherian; Kumar, Vivek; Avery, Pasco B; McKenzie, Cindy L; Osborne, Lance S

    2017-08-01

    Rhynocoris fuscipes (Fab.) (Hemiptera: Reduviidae) is a generalist predator of cotton pests and is commonly found inhabiting cotton-growing regions in southern India. With the goal of integrating this predator in standard management practices used against cotton pests on a commercial scale, (1) we developed a protocol for adult group rearing of this predator inside micro-environmental cages (MECs), and (2) we evaluated the biocontrol potential of mass-produced predators against cotton pests under potted and field conditions. Higher fecundity and adult longevity of R. fuscipes was recorded in the MECs than under natural growing conditions. The reduviid predator preferred stones and fallen leaves as hiding places in the MECs. The predator showed a higher biocontrol potential during the night hours against two pests, Phenacoccus solenopsis Tinsley and Dysdercus cingulatus (Fab.), than during the day under potted conditions. Under field conditions, R. fuscipes significantly reduced the population of Aphis gossypii Glover, P. solenopsis, D. cingulatus and Helicoverpa armigera (Hübner) by 28, 70, 29 and 50%, respectively. No negative impact of R. fuscipes was reported on other natural enemies present in the cotton agroecosystem. Significantly higher crop yield and cost benefit ratio were observed in R. fuscipes-released plots than in the control plots. The results suggest that R. fuscipes can be mass produced efficiently under controlled conditions in MECs, and used in an integrated management program for multiple cotton pests. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  8. Microbial control of phytophagous invertebrate pests in South Africa: Current status and future prospects.

    Hatting, Justin L; Moore, Sean D; Malan, Antoinette P

    2018-02-07

    Invertebrate pests pose a significant threat to food security on the African continent. In response, South Africa has become one of the largest importers of chemical pesticides in sub-Saharan Africa, with several hundred active ingredients registered. To address the over-reliance on such chemicals, the South African Department of Agriculture, Forestry and Fisheries (DAFF) has eliminated or restricted several pesticides since the late 1970s. The recent launch of the South African National Bio-Economy Strategy and establishment of the South African Bioproducts Organisation (SABO), together with new guidelines for registration of biopesticides in 2015, also support this endeavour. Concurrently, entomopathogen-related research and bioproduct development has increased over the past decade. Currently, 31 products (seven manufactured locally) are registered under the Fertilizers, Farm Feeds, Agricultural Remedies and Stock Remedies Act 36 of 1947. Commercially important microbes include Beauveria bassiana (Cordycipitaceae), Metarhizium anisopliae (Clavicipitaceae), Cydia pomonella granulovirus, Cryptophlebia leucotreta granulovirus, Helicoverpa armigera nucleopolyhedrovirus (Baculoviridae) and Bacillus thuringiensis subsp. kurstaki and B. thuringiensis subsp. aizawai (Bacillaceae). Both parasitic and entomopathogenic nematodes (EPNs) show potential for development as bioinsecticides with one commercial EPN product, based on Heterorhabditis bacteriophora (Heterorhabditidae), registered under the Act. Rapid scientific progression, supported by a favourable legislative environment, should facilitate further advances in microbial control of phytophagous invertebrate pests in South Africa. Copyright © 2018 Elsevier Inc. All rights reserved.

  9. Transgenic plants expressing the AaIT/GNA fusion protein show increased resistance and toxicity to both chewing and sucking pests.

    Liu, Shu-Min; Li, Jie; Zhu, Jin-Qi; Wang, Xiao-Wei; Wang, Cheng-Shu; Liu, Shu-Sheng; Chen, Xue-Xin; Li, Sheng

    2016-04-01

    The adoption of pest-resistant transgenic plants to reduce yield losses and decrease pesticide use has been successful. To achieve the goal of controlling both chewing and sucking pests in a given transgenic plant, we generated transgenic tobacco, Arabidopsis, and rice plants expressing the fusion protein, AaIT/GNA, in which an insecticidal scorpion venom neurotoxin (Androctonus australis toxin, AaIT) is fused to snowdrop lectin (Galanthus nivalis agglutinin, GNA). Compared with transgenic tobacco and Arabidopsis plants expressing AaIT or GNA, transgenic plants expressing AaIT/GNA exhibited increased resistance and toxicity to one chewing pest, the cotton bollworm, Helicoverpa armigera. Transgenic tobacco and rice plants expressing AaIT/GNA showed increased resistance and toxicity to two sucking pests, the whitefly, Bemisia tabaci, and the rice brown planthopper, Nilaparvata lugens, respectively. Moreover, in the field, transgenic rice plants expressing AaIT/GNA exhibited a significant improvement in grain yield when infested with N. lugens. This study shows that expressing the AaIT/GNA fusion protein in transgenic plants can be a useful approach for controlling pests, particularly sucking pests which are not susceptible to the toxin in Bt crops. © 2015 Institute of Zoology, Chinese Academy of Sciences.

  10. Identification and characterization of aldehyde oxidases (AOXs) in the cotton bollworm

    Xu, Wei; Liao, Yalin

    2017-12-01

    Aldehyde oxidases (AOXs) are a family of metabolic enzymes that oxidize aldehydes into carboxylic acids; therefore, they play critical roles in detoxification and degradation of chemicals. By using transcriptomic and genomic approaches, we successfully identified six putative AOX genes (HarmAOX1-6) from cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae). In silico expression profile, reverse transcription (RT)-PCR, and quantitative PCR (qPCR) analyses showed that HarmAOX1 is highly expressed in adult antennae, tarsi, and larval mouthparts, so they may play an important role in degrading plant-derived compounds. HarmAOX2 is highly and specifically expressed in adult antennae, suggesting a candidate pheromone-degrading enzyme (PDE) to inactivate the sex pheromone components (Z)-11-hexadecenal and (Z)-9-hexadecenal. RNA sequencing data further demonstrated that a number of host plants they feed on could significantly upregulate the expression levels of HarmAOX1 in larvae. This study improves our understanding of insect aldehyde oxidases and insect-plant interactions.

  11. Diversity and abundance of lepidopteran populations from selected crops of district faisalabad, pakistan

    Maalik, S.; Rana, S.A.; Khan, H.A.; Ashfaq, M.

    2012-01-01

    Lepidopterans are represented by one of the most diverse group of insects. They are phytophagous as well as pollinators at the same time. During present study four crops i.e Wheat, Fodder, Brassica and Vegetables were sampled to assess the diversity and abundance of Lepidopteran populations. A total of 2811 specimens belonging to 14 species and 6 families were recorded. Pieris brassicae (29.46%) was the dominant species followed by Trichoplusia ni (19.28%), Helicoverpa Zea (11.78%), Helicoverpa armigera (11.60%), Spodoptera exigua (6.65%), Psedoplusia includes (5.09%), Spodoptera litura (3.81%), Agrotis ipsilon (4.87%), Plutella xylostella (2.92%), Lymatria dispar (2.24%), Pieris rapae (0.92%), Galleria mellonella (0.71%), Evergestris rimosalis (0.53%) and Menduca sexta (0.14%). Significant differences were observed among different crops by applying Shannon Diversity Index and T- test. CA (Cluster analysis) represented the species association with different crops. Majority of the species showed association with Vegetables and Fodder and least association was observed with Wheat. Such types of studies are necessary to design integrated pest management programs to control these pests. (author)

  12. MetaGaAP: A Novel Pipeline to Estimate Community Composition and Abundance from Non-Model Sequence Data

    Christopher Noune

    2017-02-01

    Full Text Available Next generation sequencing and bioinformatic approaches are increasingly used to quantify microorganisms within populations by analysis of ‘meta-barcode’ data. This approach relies on comparison of amplicon sequences of ‘barcode’ regions from a population with public-domain databases of reference sequences. However, for many organisms relevant ‘barcode’ regions may not have been identified and large databases of reference sequences may not be available. A workflow and software pipeline, ‘MetaGaAP,’ was developed to identify and quantify genotypes through four steps: shotgun sequencing and identification of polymorphisms in a metapopulation to identify custom ‘barcode’ regions of less than 30 polymorphisms within the span of a single ‘read’, amplification and sequencing of the ‘barcode’, generation of a custom database of polymorphisms, and quantitation of the relative abundance of genotypes. The pipeline and workflow were validated in a ‘wild type’ Alphabaculovirus isolate, Helicoverpa armigera single nucleopolyhedrovirus (HaSNPV-AC53 and a tissue-culture derived strain (HaSNPV-AC53-T2. The approach was validated by comparison of polymorphisms in amplicons and shotgun data, and by comparison of predicted dominant and co-dominant genotypes with Sanger sequences. The computational power required to generate and search the database effectively limits the number of polymorphisms that can be included in a barcode to 30 or less. The approach can be used in quantitative analysis of the ecology and pathology of non-model organisms.

  13. Enhanced Methanol Production in Plants Provides Broad Spectrum Insect Resistance

    Dixit, Sameer; Upadhyay, Santosh Kumar; Singh, Harpal; Sidhu, Om Prakash; Verma, Praveen Chandra; K, Chandrashekar

    2013-01-01

    Plants naturally emit methanol as volatile organic compound. Methanol is toxic to insect pests; but the quantity produced by most of the plants is not enough to protect them against invading insect pests. In the present study, we demonstrated that the over-expression of pectin methylesterase, derived from Arabidopsis thaliana and Aspergillus niger, in transgenic tobacco plants enhances methanol production and resistance to polyphagous insect pests. Methanol content in the leaves of transgenic plants was measured using proton nuclear spectroscopy (1H NMR) and spectra showed up to 16 fold higher methanol as compared to control wild type (WT) plants. A maximum of 100 and 85% mortality in chewing insects Helicoverpa armigera and Spodoptera litura larvae was observed, respectively when fed on transgenic plants leaves. The surviving larvae showed less feeding, severe growth retardation and could not develop into pupae. In-planta bioassay on transgenic lines showed up to 99 and 75% reduction in the population multiplication of plant sap sucking pests Myzus persicae (aphid) and Bemisia tabaci (whitefly), respectively. Most of the phenotypic characters of transgenic plants were similar to WT plants. Confocal microscopy showed no deformities in cellular integrity, structure and density of stomata and trichomes of transgenic plants compared to WT. Pollen germination and tube formation was also not affected in transgenic plants. Cell wall enzyme transcript levels were comparable with WT. This study demonstrated for the first time that methanol emission can be utilized for imparting broad range insect resistance in plants. PMID:24223989

  14. Discordance between morphological and molecular species boundaries among Caribbean species of the reef sponge Callyspongia.

    DeBiasse, Melissa B; Hellberg, Michael E

    2015-02-01

    Sponges are among the most species-rich and ecologically important taxa on coral reefs, yet documenting their diversity is difficult due to the simplicity and plasticity of their morphological characters. Genetic attempts to identify species are hampered by the slow rate of mitochondrial sequence evolution characteristic of sponges and some other basal metazoans. Here we determine species boundaries of the Caribbean coral reef sponge genus Callyspongia using a multilocus, model-based approach. Based on sequence data from one mitochondrial (COI), one ribosomal (28S), and two single-copy nuclear protein-coding genes, we found evolutionarily distinct lineages were not concordant with current species designations in Callyspongia. While C. fallax,C. tenerrima, and C. plicifera were reciprocally monophyletic, four taxa with different morphologies (C. armigera,C. longissima,C. eschrichtii, and C. vaginalis) formed a monophyletic group and genetic distances among these taxa overlapped distances within them. A model-based method of species delimitation supported collapsing these four into a single evolutionary lineage. Variation in spicule size among these four taxa was partitioned geographically, not by current species designations, indicating that in Callyspongia, these key taxonomic characters are poor indicators of genetic differentiation. Taken together, our results suggest a complex relationship between morphology and species boundaries in sponges.

  15. Assessment of pest and pesticide trends in vegetable crops in united arab emirates and sultanate of oman

    Waakeh, W.; Aldahmani, J.H.; Deadman, M.L.; Saadi, A.A.

    2007-01-01

    A preliminary survey on pesticide uses in 40 vegetable-growing farms representing different agricultural areas in Oman and the UAE, twenty farms from each country, revealed that all the vegetable farms used pesticides for crop protection. Among the major insect-pests, white flies (Bemisia tabaci), leafminers (Liriomyza trifolii), melon fruit flies (Bactrocera ciliatus), aphids (Aphis spp.) and tobacco leafworm (Spodoptera litteralis) were recorded in Omani farms. In the UAE, white flies, leafminers, cutworms (Agrotis ypsilan), tomato fruitworms (Helicoverpa armigera) and eggplant fruitworms (Leucinodes orbonalis) were the 5 top insect-pests. Among the plant diseases, powdery mildew (Erysiphe spp.), blight (Alternaria spp.), damping off (Pythium spp.), leafspot (Alternaria spp.) and mosaic (CMV) Were major cause of vegetable diseases in Omani farms; whereas, damping off (Pythium aphanidermatum), downy mildew (Pseudoperonspora cubensis), early blight (Alternaria solani), septoria leaf spot (Septoria lycopersici) and anthracnose rip rot (colletotrichum spp.) were the most predominant diseases encountered in most UAE farms. Among the most commonly used pesticides, 29 insecticides, 16 fungicides and 3 herbicides were used by the vegetable farmers. Around 55% of Omani farms used routine application of pesticides, irrespective of the pest presence. Whereas, in the UAE, most farmers started to spray pesticides at 6-20% pest (insect, disease and weeds) infection. Over 65 of the farms, in both the countries, received chemical pest management information from the sales representatives. (author)

  16. Coincidence of pheromone and plant odor leads to sensory plasticity in the heliothine olfactory system.

    Elena Ian

    Full Text Available Male moths possess a highly specialized olfactory system comprised of two segregated sub-arrangements dedicated to processing information about plant odors and pheromones, respectively. Communication between these two sub-systems has been described at the peripheral level, but relatively little is known about putative interactions at subsequent synaptic relays. The male moth faces the challenge of seeking out the conspecific female in a highly dynamic odor world. The female-produced pheromone blend, which is a limited resource serving as guidance for the male, will reach his antennae in intermittent pockets of odor filaments mixed with volatiles from various plants. In the present study we performed calcium imaging for measuring odor-evoked responses in the uni-glomerular antennal-lobe projection neurons (analog to mitral cells in the vertebrate olfactory bulb of Helicoverpa armigera. In order to investigate putative interactions between the two sub-systems tuned to plant volatiles and pheromones, respectively, we performed repeated stimulations with a selection of biologically relevant odors. We found that paired stimulation with a plant odor and the pheromone led to suppressed responses in both sub-systems as compared to those evoked during initial stimulation including application of each odor stimulus alone. The fact that the suppression persisted also after pairing, indicates the existence of a Hebbian-like plasticity in the primary olfactory center established by temporal pairing of the two odor stimulation categories.

  17. Beauveria medogensis sp. nov., a new fungus of the entomopathogenic genus from China.

    Imoulan, Abdessamad; Wu, Hai-Jun; Lu, Wei-Lai; Li, Yi; Li, Bin-Bin; Yang, Rei-Heng; Wang, Wen-Jing; Wang, Xiao-Liang; Kirk, Paul M; Yao, Yi-Jian

    2016-09-01

    Beauveria is among the most ubiquitous genera of entomopathogenic fungi throughout the world. A previously unknown species of the genus was recently discovered from a soil sample collected from Tibetan Plateau, China and is here described as new to science, B. medogensis sp. nov. The new species is distinguished from its closest relatives based on both morphological characterization and molecular phylogenetic analyses. Beauveria medogensis is characterized by globose to subglobose conidia, morphologically similar to some other species of in the genus, but was conclusively separated from those species in the phylogenetic analyses including sequences of four nuclear genes (RPB1, RPB2, TEF1 and Bloc). The new species was clustered in the analyses in a single terminal lineage which was grouped with B. australis sequences together as a sister clade to the B. brongniartii terminal clade. Although molecularly closely related, the new species is distinct morphologically from its closest sisters, B. australis and B. brongniartii, in producing globose to subglobose conidia rather than subglobose, broadly ellipsoid to ellipsoid conidia or ellipsoidal to cylindrical conidia. As isolated from a soil sample, the entomopathogenicity of the new species has been confirmed using Helicoverpa armigera and Tenebrio molitor larvae. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Developing Bisexual Attract-and-Kill for Polyphagous Insects: Ecological Rationale versus Pragmatics.

    Gregg, Peter C; Del Socorro, Alice P; Hawes, Anthony J; Binns, Matthew R

    2016-07-01

    We discuss the principles of bisexual attract-and-kill, in which females as well as males are targeted with an attractant, such as a blend of plant volatiles, combined with a toxicant. While the advantages of this strategy have been apparent for over a century, there are few products available to farmers for inclusion in integrated pest management schemes. We describe the development, registration, and commercialization of one such product, Magnet(®), which was targeted against Helicoverpa armigera and H. punctigera in Australian cotton. We advocate an empirical rather than theoretical approach to selecting and blending plant volatiles for such products, and emphasise the importance of field studies on ecologically realistic scales of time and space. The properties required of insecticide partners also are discussed. We describe the studies that were necessary to provide data for registration of the Magnet(®) product. These included evidence of efficacy, including local and area-wide impacts on the target pest, non-target impacts, and safety for consumers and applicators. In the decade required for commercial development, the target market for Magnet(®) has been greatly reduced by the widespread adoption of transgenic insect-resistant cotton in Australia. We discuss potential applications in resistance management for transgenic cotton, and for other pests in cotton and other crops.

  19. Transgenic Cotton Plants Expressing Double-stranded RNAs Target HMG-CoA Reductase (HMGR) Gene Inhibits the Growth, Development and Survival of Cotton Bollworms.

    Tian, Geng; Cheng, Linlin; Qi, Xuewei; Ge, Zonghe; Niu, Changying; Zhang, Xianlong; Jin, Shuangxia

    2015-01-01

    RNA interference (RNAi) has been developed as a powerful technique in the research of functional genomics as well as plant pest control. In this report, double-stranded RNAs (dsRNA) targeting 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) gene, which catalyze a rate-limiting enzymatic reaction in the mevalonate pathway of juvenile hormone (JH) synthesis in cotton bollworm, was expressed in cotton plants via Agrobacterium tumefaciens-mediated transformation. PCR and Sothern analysis revealed the integration of HMGR gene into cotton genome. RT-PCR and qRT-PCR confirmed the high transcription level of dsHMGR in transgenic cotton lines. The HMGR expression both in transcription and translation level was significantly downregulated in cotton bollworms (helicoverpa armigera) larvae after feeding on the leaves of HMGR transgenic plants. The transcription level of HMGR gene in larvae reared on transgenic cotton leaves was as much as 80.68% lower than that of wild type. In addition, the relative expression level of vitellogenin (Vg, crucial source of nourishment for offspring embryo development) gene was also reduced by 76.86% when the insect larvae were fed with transgenic leaves. The result of insect bioassays showed that the transgenic plant harboring dsHMGR not only inhibited net weight gain but also delayed the growth of cotton bollworm larvae. Taken together, transgenic cotton plant expressing dsRNAs successfully downregulated HMGR gene and impaired the development and survival of target insect, which provided more option for plant pest control.

  20. Juvenile hormone prevents 20-hydroxyecdysone-induced metamorphosis by regulating the phosphorylation of a newly identified broad protein.

    Cai, Mei-Juan; Liu, Wen; Pei, Xu-Yang; Li, Xiang-Ru; He, Hong-Juan; Wang, Jin-Xing; Zhao, Xiao-Fan

    2014-09-19

    The steroid hormone 20-hydroxyecdysone (20E) initiates insect molting and metamorphosis. By contrast, juvenile hormone (JH) prevents metamorphosis. However, the mechanism by which JH inhibits metamorphosis remains unclear. In this study, we propose that JH induces the phosphorylation of Broad isoform Z7 (BrZ7), a newly identified protein, to inhibit 20E-mediated metamorphosis in the lepidopteran insect Helicoverpa armigera. The knockdown of BrZ7 in larvae inhibited metamorphosis by repressing the expression of the 20E response gene. BrZ7 was weakly expressed and phosphorylated during larval growth but highly expressed and non-phosphorylated during metamorphosis. JH regulated the rapid phosphorylation of BrZ7 via a G-protein-coupled receptor-, phospholipase C-, and protein kinase C-triggered pathway. The phosphorylated BrZ7 bound to the 5'-regulatory region of calponin to regulate its expression in the JH pathway. Exogenous JH induced BrZ7 phosphorylation to prevent metamorphosis by suppressing 20E-related gene transcription. JH promoted non-phosphorylated calponin interacting with ultraspiracle protein to activate the JH pathway and antagonize the 20E pathway. This study reveals one of the possible mechanisms by which JH counteracts 20E-regulated metamorphosis by inducing the phosphorylation of BrZ7. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. Juvenile Hormone Prevents 20-Hydroxyecdysone-induced Metamorphosis by Regulating the Phosphorylation of a Newly Identified Broad Protein*

    Cai, Mei-Juan; Liu, Wen; Pei, Xu-Yang; Li, Xiang-Ru; He, Hong-Juan; Wang, Jin-Xing; Zhao, Xiao-Fan

    2014-01-01

    The steroid hormone 20-hydroxyecdysone (20E) initiates insect molting and metamorphosis. By contrast, juvenile hormone (JH) prevents metamorphosis. However, the mechanism by which JH inhibits metamorphosis remains unclear. In this study, we propose that JH induces the phosphorylation of Broad isoform Z7 (BrZ7), a newly identified protein, to inhibit 20E-mediated metamorphosis in the lepidopteran insect Helicoverpa armigera. The knockdown of BrZ7 in larvae inhibited metamorphosis by repressing the expression of the 20E response gene. BrZ7 was weakly expressed and phosphorylated during larval growth but highly expressed and non-phosphorylated during metamorphosis. JH regulated the rapid phosphorylation of BrZ7 via a G-protein-coupled receptor-, phospholipase C-, and protein kinase C-triggered pathway. The phosphorylated BrZ7 bound to the 5′-regulatory region of calponin to regulate its expression in the JH pathway. Exogenous JH induced BrZ7 phosphorylation to prevent metamorphosis by suppressing 20E-related gene transcription. JH promoted non-phosphorylated calponin interacting with ultraspiracle protein to activate the JH pathway and antagonize the 20E pathway. This study reveals one of the possible mechanisms by which JH counteracts 20E-regulated metamorphosis by inducing the phosphorylation of BrZ7. PMID:25096576

  2. The evolution and expression of the moth visual opsin family.

    Pengjun Xu

    Full Text Available Because visual genes likely evolved in response to their ambient photic environment, the dichotomy between closely related nocturnal moths and diurnal butterflies forms an ideal basis for investigating their evolution. To investigate whether the visual genes of moths are associated with nocturnal dim-light environments or not, we cloned long-wavelength (R, blue (B and ultraviolet (UV opsin genes from 12 species of wild-captured moths and examined their evolutionary functions. Strong purifying selection appeared to constrain the functions of the genes. Dark-treatment altered the levels of mRNA expression in Helicoverpa armigera such that R and UV opsins were up-regulated after dark-treatment, the latter faster than the former. In contrast, B opsins were not significantly up-regulated. Diel changes of opsin mRNA levels in both wild-captured and lab-reared individuals showed no significant fluctuation within the same group. However, the former group had significantly elevated levels of expression compared with the latter. Consequently, environmental conditions appeared to affect the patterns of expression. These findings and the proportional expression of opsins suggested that moths potentially possessed color vision and the visual system played a more important role in the ecology of moths than previously appreciated. This aspect did not differ much from that of diurnal butterflies.

  3. The halo effect: suppression of pink bollworm on non-Bt cotton by Bt cotton in China.

    Peng Wan

    Full Text Available In some previously reported cases, transgenic crops producing insecticidal proteins from Bacillus thuringiensis (Bt have suppressed insect pests not only in fields planted with such crops, but also regionally on host plants that do not produce Bt toxins. Here we used 16 years of field data to determine if Bt cotton caused this "halo effect" against pink bollworm (Pectinophora gossypiella in six provinces of the Yangtze River Valley of China. In this region, the percentage of cotton hectares planted with Bt cotton increased from 9% in 2000 to 94% in 2009 and 2010. We found that Bt cotton significantly decreased the population density of pink bollworm on non-Bt cotton, with net decreases of 91% for eggs and 95% for larvae on non-Bt cotton after 11 years of Bt cotton use. Insecticide sprays targeting pink bollworm and cotton bollworm (Helicoverpa armigera decreased by 69%. Previously reported evidence of the early stages of evolution of pink bollworm resistance to Bt cotton in China has raised concerns that if unchecked, such resistance could eventually diminish or eliminate the benefits of Bt cotton. The results reported here suggest that it might be possible to find a percentage of Bt cotton lower than the current level that causes sufficient regional pest suppression and reduces the risk of resistance.

  4. Lung perfusion and emphysema distribution affect the outcome of endobronchial valve therapy

    Thomsen C

    2016-06-01

    Full Text Available Christian Thomsen,1 Dorothea Theilig,2 Dominik Herzog,1 Alexander Poellinger,2 Felix Doellinger,2 Nils Schreiter,3 Vera Schreiter,2 Dirk Schürmann,1 Bettina Temmesfeld-Wollbrueck,1 Stefan Hippenstiel,1 Norbert Suttorp,1 Ralf-Harto Hubner1 1Department of Internal Medicine/Infectious Diseases and Respiratory Medicine, 2Institute of Radiology, 3Institute of Nuclear Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany Abstract: The exclusion of collateral ventilation (CV and other factors affect the clinical success of endoscopic lung volume reduction (ELVR. However, despite its benefits, the outcome of ELVR remains difficult to predict. We investigated whether clinical success could be predicted by emphysema distribution assessed by computed tomography scan and baseline perfusion assessed by perfusion scintigraphy. Data from 57 patients with no CV in the target lobe (TL were retrospectively analyzed after ELVR with valves. Pulmonary function tests (PFT, St George’s Respiratory Questionnaire (SGRQ, and 6-minute walk tests (6MWT were performed on patients at baseline. The sample was grouped into high and low levels at the median of TL perfusion, ipsilateral nontarget lobe (INL perfusion, and heterogeneity index (HI. These groups were analyzed for association with changes in outcome parameters from baseline to 3 months follow-up. Compared to baseline, patients showed significant improvements in PFT, SGRQ, and 6MWT (all P≤0.001. TL perfusion was not associated with changes in the outcome. High INL perfusion was significantly associated with increases in 6MWT (P=0.014, and high HI was associated with increases in forced expiratory volume in 1 second (FEV1, (P=0.012. Likewise, there were significant correlations for INL perfusion and improvement of 6MWT (r=0.35, P=0.03 and for HI and improvement in FEV1 (r=0.45, P=0.001. This study reveals new attributes that associate with positive outcomes for patient selection prior to ELVR

  5. Comparison of distinctive models for calculating an interlobar emphysema heterogeneity index in patients prior to endoscopic lung volume reduction

    Theilig D

    2017-06-01

    Full Text Available Dorothea Theilig,1 Felix Doellinger,1 Alexander Poellinger,1 Vera Schreiter,1 Konrad Neumann,2 Ralf-Harto Hubner31Department of Radiology, Charité Campus Virchow Klinikum, Charité, Universitätsmedizin Berlin, Berlin, Germany; 2Institute of Biometrics and Clinical Epidemiology, Charité Campus Benjamin Franklin, Charité, Universitätsmedizin Berlin, Berlin, Germany; 3Department of Pneumology, Charité Campus Virchow Klinikum, Charité, Universitätsmedizin Berlin, Berlin, GermanyBackground: The degree of interlobar emphysema heterogeneity is thought to play an important role in the outcome of endoscopic lung volume reduction (ELVR therapy of patients with advanced COPD. There are multiple ways one could possibly define interlobar emphysema heterogeneity, and there is no standardized definition.Purpose: The aim of this study was to derive a formula for calculating an interlobar emphysema heterogeneity index (HI when evaluating a patient for ELVR. Furthermore, an attempt was made to identify a threshold for relevant interlobar emphysema heterogeneity with regard to ELVR.Patients and methods: We retrospectively analyzed 50 patients who had undergone technically successful ELVR with placement of one-way valves at our institution and had received lung function tests and computed tomography scans before and after treatment. Predictive accuracy of the different methods for HI calculation was assessed with receiver-operating characteristic curve analysis, assuming a minimum difference in forced expiratory volume in 1 second of 100 mL to indicate a clinically important change.Results: The HI defined as emphysema score of the targeted lobe (TL minus emphysema score of the ipsilateral nontargeted lobe disregarding the middle lobe yielded the best predicative accuracy (AUC =0.73, P=0.008. The HI defined as emphysema score of the TL minus emphysema score of the lung without the TL showed a similarly good predictive accuracy (AUC =0.72, P=0.009. Subgroup

  6. Plankton and Macrobiota Composition and Diversity of Three Tropical Freshwaters Rivers in Ogun and Ondo States, Southwest Nigeria

    Taofikat Abosede ADESALU

    2016-06-01

    Full Text Available Three different rivers in Ogun and Ondo states were investigated for both micro and macro-biota of the water bodies. Several physical and chemical properties of these rivers were determined. The pH value of the studied water bodies was essentially neutral with salinity values between 0.02 - 4.0‰. Microalgae communities were represented by three divisions: Cyanophyta, Bacillariophyta and Chlorophyta at Oluwa and Ifara Rivers (Ondo state, while at Ibefun River (Ogun state, five divisions: Cyanophyta, Bacillariophyta, Chlorophyta, Euglenophyta and Pyrrhophyta were identified. Diatoms dominated these water bodies, with Navicula radiosa Kutz. at Ifara River, Fragilaria sp. in Oluwa River, while out of 90 algal taxa identified in Ibefun river, 64 were diatoms species belonging to 26 genera, with Melosira sp. and Synedra sp. recording the highest numbers of cell count. Dinoflagellates recorded only Peridinium sp. while Phacus orbicularis Hubner and Trachelomonas sp. dominated the euglenoids. For the zooplankton composition at Ibefun, rotifers (75.95% were represented by Brachionus sp., which recorded 62.03%, and Gastropus sp. with 13.92% of the total zooplankton, thus dominated the spectrum, while the copepod recorded 22.78% of the total organisms, with Copilia sp. and Euchirella sp. having 8.86% each. The macrobenthic invertebrates were represented by 3 taxa, belonging to 3 groups, with the dominant group Insecta accounted for 57% of the total individuals (7 individuals/m2, while Oligochaeta and Hirudinea accounted for 29% and 14% respectively of the total individuals at Oluwa and Ifara Rivers. At Ibefun River, the macrobenthic invertebrates were represented by 5 taxa, belonging to 3 groups, Bivalves, Oligochaeta and Insecta, with bivalves being the dominant group (51.7% of the total individuals, as 64 individuals/m2, while Oligochaeta and Insecta accounted for 26.6% and 21.9% respectively of the total individuals. The dominant taxon, Macoma cumana

  7. First records of freshwater molluscs from the ecological reserve El Edén, Quintana Roo, México Primeros registros de moluscos dulceacuícolas de la Reserva Ecológica El Edén, Quintana Roo, México

    Roberto Cózatl-Manzano

    2007-12-01

    Full Text Available The diversity of the freshwater molluscs at El Edén was unknown. This is the first treatment of them, allowing us to compare spatial and temporal species distribution. Eleven species of freshwater molluscs were found in 2 surveys carried in March (dry season and September (rainy season 1998 at the reserve El Edén. A total of 266 individuals were collected; 8 pulmonates, Mayabina spiculata, Mexinauta impluviatus, Physa sp., Biomphalaria havanensis, Drepanotrema lucidum, Drepanotrema kermatoides, Planorbella (Pierosoma trivolvis, and Planorbula armigera; 2 prosobranchs, Pyrgophorus sp. and Pomacea flagellata; and one bivalve, Musculium transversum. Pulmonata dominate over Prosobranchia species in diversity. No significant differences were observed in diversity between dry and rainy seasons. However, species abundance recorded in both seasons was very low, probably due to a combination of inadequate food resources and disadvantageous climate (periodic conditions of drought and flooding. Further studies using a combination of different sampling methods and more frequent samplings are needed to confirm or identify these factors. We suggest that future studies should focus on cultivation of species with economic potential such as the apple snail Pomacea flagellata.La diversidad de moluscos dulceacuícolas de la Reserva Ecológica El Edén se desconocía; este estudio constituye su primer registro. Asimismo, esta investigación permite comparar la distribución espacial y temporal de las especies registradas. Las recolectas se efectuaron en marzo (temporada de sequía y septiembre (lluvia de 1998. Se registran 11 especies (266 individuos en total, 8 pulmonados: Mayabina spiculata, Mexinauta impluviatus, Physa sp., Biomphalaria havanensis, Drepanotrema lucidum, Drepanotrema kermatoides, Planorbella (Pierosoma trivolvis y Planorbula armigera; dos prosobranquios: Pyrgophorus sp. y Pomacea flagellata, y un bivalvo: Musculium transversum. Los pulmonados

  8. Laboratory Assessment on Virulence of Nomuraea rileyi against Noctuid Larvae%莱氏野村菌对夜蛾科害虫防治潜力的室内评测

    周立峰; 于士军; 刘元兵; 王滨

    2012-01-01

    本文用喷雾法测定了5株莱氏野村菌Nomuraea rileyi对棉铃虫Helicoverpa armigera、甜菜夜蛾Spodoptera exigua和斜纹夜蛾Spodoptera litura 3种夜蛾科害虫的致病力。配制孢子悬浮液对3种夜蛾科害虫进行雾化接种,孢子附着量为188.9~4048.3孢子.mm 2。接种后幼虫置于(24±1)℃和12L∶12D条件下人工饲料饲养,每天观察直至化蛹。时间-剂量-死亡率模型分析显示:5株莱氏野村菌菌株接种量为188.9~4048.3孢子.mm 2时,斜纹夜蛾第10 d的侵染率为60%~95%;菌株Nr15对斜纹夜蛾显示出极高的毒力水平(LC50=266.7孢子.mm 2,4048.3孢子.mm 2浓度下的LT50=5.81 d),第10 d的侵染率达95%。供试菌株对棉铃虫和甜菜夜蛾的致病力相对较弱,侵染率均不足50%。研究表明,莱氏野村菌菌株对夜蛾科害虫体现出明显的寄主专化性,且有明显的量效关系。%In the current study,a laboratory bioassay was developed to measure the pathogenicities of five Nomuraea rileyi strains against Helicoverpa armigera,Spodoptera exigua and Spodoptera litura of noctuid larvae.The larvae were inoculated with conidia suspensions of N.rileyi at concentrations of 188.9 4048.3 conidia.mm 2 by a Potter Spray Tower,with 0.05% Tween-80 as control.After inoculation,the larvae were individually fed on artificial diet in plastic boxes at(24±1) ℃ and 12L:12D until pupated.Time-dose-mortality model was used to analyze the effect and indicated that the 5 fungal strains could kill 60% 95% of S.litura larvae at concentrations of 188.9 4048.3 conidia.mm 2within 10 d after conidia inoculation.Strain Nr15 demonstrated high virulence to S.litura larvae with a LC50value of 266.7 conidia.mm 2and a LT50value of 5.81 d at the concentration of 4048.3 conidia.mm 2,whereas mortalities of H.armigera and S.exigua didn’t reached 50%.The difference of mortality and fungal infection indicated that there is a host-specificity of N.rileyi strains to noctuid

  9. Environmental Factors in the Growth of Jatropha at Potorono Village, Yogyakarta

    Mohammad Nurcholis

    2015-01-01

    Full Text Available Jatropha curcas is a perennial crop that has been known by Indonesian people for more than seven decades as a plant that produces renewable biofuel. In the present decade, plants producing biofuel are expected to be developed to overcome the lowering nonrenewable fuel reserves. There is a myth that jatropha can grow well on marginal lands and draught condition, perform well on non-fertile soils, no need for agronomic management and is resistant to plant pests and diseases. This study was conducted to identify the environmental factors that influenced the growth of jatropha on the marginal land at Potorono village, Yogyakarta Province, Indonesia. Jatropha has been planted by local people at the village road sides and on the marginal land field at the local governmental land in this village. They grew jatropha on these areas with the purpose of preventing competition of area utilization with food crops. The results showed that the growth of jatropha was restricted by low content of organic matter, plant nutrition and poor soil drainage. Applications of manure and macro nutrients (N, P and K to this crop were able to increase crop performance. The number of shoots, flowers and fruit bunches increased by manure and nutrients treatments. Field observation showed that there were several plant pests, such as Aspidiotus sp., Paracoccus marginatus, Poliphagotarsonemus latus, Selenothrips rubrocinctus, Chrysochoris javanus, Valanga nigricornis, Chloracris prasina, and Helicoverpa armigera that attacked plant leaves and fruits. There were plant leaf necrotic symptoms that caused by plant pathogens were also observed. The diseases are bacterial leaf spot (Xanthomonas ricinicola, cercospora leaf spot (Cercospora ricinella and rust (Phakopsora jatrophicola. Thus, jatropha is like any other plants that need a good agro-ecological condition to grow well and produce high yield.

  10. Transmission of Different Nucleopolyhedroviruses by Two Ectoparasitoids – Bracon hebetor Say (Hymenoptera: Braconidae and Euplectrus plathypenae (Howard (Hymenoptera: Eulophidae

    Emanouela E. Stoianova

    2010-01-01

    Full Text Available The transmission of nucleopolyhedroviruses (NPVs of Autographa gamma (AgNPV,Mamestra brassicae (MbNPV, Lacanobia oleraceae (LoNPV, Helicoverpa armigera (HaNPVand Xantia c-nigrum (XnNPV to their relevant larvae by the ectoparasitoid Bracon hebetorand the transmission of the multiple-enveloped NPVs of Spodoptera exigua (SeMNPV andSpodoptera frugiperda (SfMNPV by the ectoparasitoid Euplectrus plathypenae was examined.Two methods of contamination of the both parasitoids (exposure to infected hostsand total body surface and two subsequent transmissions of the viruses by Bracon hebetorto healthy hosts were tested. The results showed that both parasitoids were capable tobe mechanical vectors of the tested NPVs. Every Bracon hebetor female was able to transmitsubsequently twice the virus in 27% to 52.2% of the five Noctuidae species by preliminaryexposing to infected larvae. The second method of contamination (applying virus suspensionto the total body surface of the parasitoid was also efficient causing virus infection inbetween 29.4% and 54.15% of the larvae.The parasitoid E. plathypenae transmited the virus from infected to noninfected larvaein 20% and 25.57% of the S. frugiperda and S. exigua larvae, and 6.43% and 11.10%, respectivelyof them died from the virus infection. The same observation was established by thesecond method of contamination – respectively 33.33% and 40% infection and between13.23% and 16.67% mortality. The mortality of all tested larvae exposed to virus contaminated parasitoids was higherwhen the parasitoid entire body surface had been artificially contaminated with the virusthan when the parasitoid itself was previously allowed to oviposit the larvae.

  11. Transgenic cotton coexpressing Vip3A and Cry1Ac has a broad insecticidal spectrum against lepidopteran pests.

    Chen, Wen-Bo; Lu, Guo-Qing; Cheng, Hong-Mei; Liu, Chen-Xi; Xiao, Yu-Tao; Xu, Chao; Shen, Zhi-Cheng; Wu, Kong-Ming

    2017-10-01

    Although farmers in China have grown transgenic Bt-Cry1Ac cotton to resist the major pest Helicoverpa armigera since 1997 with great success, many secondary lepidopteran pests that are tolerant to Cry1Ac are now reported to cause considerable economic damage. Vip3AcAa, a chimeric protein with the N-terminal part of Vip3Ac and the C-terminal part of Vip3Aa, has a broad insecticidal spectrum against lepidopteran pests and has no cross resistance to Cry1Ac. In the present study, we tested insecticidal activities of Vip3AcAa against Spodoptera litura, Spodoptera exigua, and Agrotis ipsilon, which are relatively tolerant to Cry1Ac proteins. The bioassay results showed that insecticidal activities of Vip3AcAa against these three pests are superior to Cry1Ac, and after an activation pretreatment, Vip3AcAa retained insecticidal activity against S. litura, S. exigua and A. ipsilon that was similar to the unprocessed protein. The putative receptor for this chimeric protein in the brush border membrane vesicle (BBMV) in the three pests was also identified using biotinylated Vip3AcAa toxin. To broaden Bt cotton activity against a wider spectrum of pests, we introduced the vip3AcAa and cry1Ac genes into cotton. Larval mortality rates for S. litura, A. ipsilon and S. exigua that had fed on this new cotton increased significantly compared with larvae fed on non-Bt cotton and Bt-Cry1Ac cotton in a laboratory experiment. These results suggested that the Vip3AcAa protein is an excellent option for a "pyramid" strategy for integrated pest management in China. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Complexity and variability of gut commensal microbiota in polyphagous lepidopteran larvae.

    Xiaoshu Tang

    Full Text Available BACKGROUND: The gut of most insects harbours nonpathogenic microorganisms. Recent work suggests that gut microbiota not only provide nutrients, but also involve in the development and maintenance of the host immune system. However, the complexity, dynamics and types of interactions between the insect hosts and their gut microbiota are far from being well understood. METHODS/PRINCIPAL FINDINGS: To determine the composition of the gut microbiota of two lepidopteran pests, Spodoptera littoralis and Helicoverpa armigera, we applied cultivation-independent techniques based on 16S rRNA gene sequencing and microarray. The two insect species were very similar regarding high abundant bacterial families. Different bacteria colonize different niches within the gut. A core community, consisting of Enterococci, Lactobacilli, Clostridia, etc. was revealed in the insect larvae. These bacteria are constantly present in the digestion tract at relatively high frequency despite that developmental stage and diet had a great impact on shaping the bacterial communities. Some low-abundant species might become dominant upon loading external disturbances; the core community, however, did not change significantly. Clearly the insect gut selects for particular bacterial phylotypes. CONCLUSIONS: Because of their importance as agricultural pests, phytophagous Lepidopterans are widely used as experimental models in ecological and physiological studies. Our results demonstrated that a core microbial community exists in the insect gut, which may contribute to the host physiology. Host physiology and food, nevertheless, significantly influence some fringe bacterial species in the gut. The gut microbiota might also serve as a reservoir of microorganisms for ever-changing environments. Understanding these interactions might pave the way for developing novel pest control strategies.

  13. Early warning of cotton bollworm resistance associated with intensive planting of Bt cotton in China.

    Haonan Zhang

    Full Text Available Transgenic crops producing Bacillus thuringiensis (Bt toxins kill some key insect pests, but evolution of resistance by pests can reduce their efficacy. The predominant strategy for delaying pest resistance to Bt crops requires refuges of non-Bt host plants to promote survival of susceptible pests. To delay pest resistance to transgenic cotton producing Bt toxin Cry1Ac, farmers in the United States and Australia planted refuges of non-Bt cotton, while farmers in China have relied on "natural" refuges of non-Bt host plants other than cotton. Here we report data from a 2010 survey showing field-evolved resistance to Cry1Ac of the major target pest, cotton bollworm (Helicoverpa armigera, in northern China. Laboratory bioassay results show that susceptibility to Cry1Ac was significantly lower in 13 field populations from northern China, where Bt cotton has been planted intensively, than in two populations from sites in northwestern China where exposure to Bt cotton has been limited. Susceptibility to Bt toxin Cry2Ab did not differ between northern and northwestern China, demonstrating that resistance to Cry1Ac did not cause cross-resistance to Cry2Ab, and implying that resistance to Cry1Ac in northern China is a specific adaptation caused by exposure to this toxin in Bt cotton. Despite the resistance detected in laboratory bioassays, control failures of Bt cotton have not been reported in China. This early warning may spur proactive countermeasures, including a switch to transgenic cotton producing two or more toxins distinct from Cry1A toxins.

  14. Role of tomato lipoxygenase D in wound-induced jasmonate biosynthesis and plant immunity to insect herbivores.

    Yan, Liuhua; Zhai, Qingzhe; Wei, Jianing; Li, Shuyu; Wang, Bao; Huang, Tingting; Du, Minmin; Sun, Jiaqiang; Kang, Le; Li, Chang-Bao; Li, Chuanyou

    2013-01-01

    In response to insect attack and mechanical wounding, plants activate the expression of genes involved in various defense-related processes. A fascinating feature of these inducible defenses is their occurrence both locally at the wounding site and systemically in undamaged leaves throughout the plant. Wound-inducible proteinase inhibitors (PIs) in tomato (Solanum lycopersicum) provide an attractive model to understand the signal transduction events leading from localized injury to the systemic expression of defense-related genes. Among the identified intercellular molecules in regulating systemic wound response of tomato are the peptide signal systemin and the oxylipin signal jasmonic acid (JA). The systemin/JA signaling pathway provides a unique opportunity to investigate, in a single experimental system, the mechanism by which peptide and oxylipin signals interact to coordinate plant systemic immunity. Here we describe the characterization of the tomato suppressor of prosystemin-mediated responses8 (spr8) mutant, which was isolated as a suppressor of (pro)systemin-mediated signaling. spr8 plants exhibit a series of JA-dependent immune deficiencies, including the inability to express wound-responsive genes, abnormal development of glandular trichomes, and severely compromised resistance to cotton bollworm (Helicoverpa armigera) and Botrytis cinerea. Map-based cloning studies demonstrate that the spr8 mutant phenotype results from a point mutation in the catalytic domain of TomLoxD, a chloroplast-localized lipoxygenase involved in JA biosynthesis. We present evidence that overexpression of TomLoxD leads to elevated wound-induced JA biosynthesis, increased expression of wound-responsive genes and, therefore, enhanced resistance to insect herbivory attack and necrotrophic pathogen infection. These results indicate that TomLoxD is involved in wound-induced JA biosynthesis and highlight the application potential of this gene for crop protection against insects and

  15. Role of tomato lipoxygenase D in wound-induced jasmonate biosynthesis and plant immunity to insect herbivores.

    Liuhua Yan

    Full Text Available In response to insect attack and mechanical wounding, plants activate the expression of genes involved in various defense-related processes. A fascinating feature of these inducible defenses is their occurrence both locally at the wounding site and systemically in undamaged leaves throughout the plant. Wound-inducible proteinase inhibitors (PIs in tomato (Solanum lycopersicum provide an attractive model to understand the signal transduction events leading from localized injury to the systemic expression of defense-related genes. Among the identified intercellular molecules in regulating systemic wound response of tomato are the peptide signal systemin and the oxylipin signal jasmonic acid (JA. The systemin/JA signaling pathway provides a unique opportunity to investigate, in a single experimental system, the mechanism by which peptide and oxylipin signals interact to coordinate plant systemic immunity. Here we describe the characterization of the tomato suppressor of prosystemin-mediated responses8 (spr8 mutant, which was isolated as a suppressor of (prosystemin-mediated signaling. spr8 plants exhibit a series of JA-dependent immune deficiencies, including the inability to express wound-responsive genes, abnormal development of glandular trichomes, and severely compromised resistance to cotton bollworm (Helicoverpa armigera and Botrytis cinerea. Map-based cloning studies demonstrate that the spr8 mutant phenotype results from a point mutation in the catalytic domain of TomLoxD, a chloroplast-localized lipoxygenase involved in JA biosynthesis. We present evidence that overexpression of TomLoxD leads to elevated wound-induced JA biosynthesis, increased expression of wound-responsive genes and, therefore, enhanced resistance to insect herbivory attack and necrotrophic pathogen infection. These results indicate that TomLoxD is involved in wound-induced JA biosynthesis and highlight the application potential of this gene for crop protection against

  16. Cloning and characterization of the pheromone biosynthesis activating neuropeptide receptor gene in Spodoptera littoralis larvae.

    Zheng, Lei; Lytle, Christian; Njauw, Ching-Ni; Altstein, Miriam; Martins-Green, Manuela

    2007-05-15

    In noctuid moths cuticular pigmentation is regulated by the pyrokinin/pheromone biosynthesis activating neuropeptide (PK/PBAN) family, which also mediates a variety of other functions in moths and other insects. Numerous studies have shown that these neuropeptides exert their functions through activation of the PBAN receptor (PBAN-R), with subsequent Ca(2+) influx, followed by either activation of cAMP or direct activation of downstream kinases. Recently, several PBAN-Rs have been identified, all of which are from the pheromone gland of adult female moths, but evidence shows that functional PK/PBAN-Rs can also be expressed in insect larvae, where they mediate melanization and possibly other functions (e.g., diapause). Here, we identified a gene encoding a G-protein-coupled receptor from the 5th instar larval tissue of the moth Spodoptera littoralis. The cDNA of this gene contains an open reading frame with a length of 1050 nucleotides, which translates to a 350-amino acid, 42-kDa protein that shares 92% amino acid identity with Helicoverpa zea and Helicoverpa armigera PBAN-R, 81% with Bombyx mori PBAN-R and 72% with Plutella xylostella PBAN-R. The S. littoralis PBAN-R gene was stably expressed in NIH3T3 cells and transiently in HEK293 cells. We show that it mediates the dose-dependent PBAN-induced intracellular Ca(2+) response and activation of the MAP kinase via a PKC-dependent but Galphai-independent signaling mechanism. Other PK/PBAN family peptides (pheromonotropin and a C-terminally PBAN-derived peptide PBAN(28-33)NH(2)) also triggered MAP kinase activation. This receptor, together with the previously cloned PBAN-R, may facilitate our understanding of the cell-specific responses and functional diversities of this diverse neuropeptide family.

  17. Comparative venom toxicity between Pteromalus puparum and Nasonia vitripennis (Hymenoptera: Pteromalidae) toward the hemocytes of their natural hosts, non-target insects and cultured insect cells.

    Zhang, Zhong; Ye, Gong-Yin; Cai, Jun; Hu, Cui

    2005-09-01

    Crude venoms from two parasitoid species, Pteromalus puparum and Nasonia vitripennis (Hymenoptera: Pteromalidae) were assayed for biological activities toward hemocytes from two species of their natural hosts and eight species of their non-natural hosts as well as two lines of cultured Lepidoptera cells, respectively. By inhibiting the spreading and viability of insect hemocytes, the venom from P. puparum displayed significantly higher activities toward plasmatocytes and granular cells from both larvae and pupae of two natural hosts, Pieris rapae and Papilio xuthus, and lower activity toward those from Spodoptera litura, Musca domestica and Sarcophaga peregrina. However, no effect was found towards any type of hemocytes from other five insects tested, namely, Ectropis oblique, Galleria mellonella, Sesamia inferens, Bombyx mori and Parnara guttata. In contrast, the venom from N. vitripennis showed a narrower range of targeted insects. It appeared to have highly adverse effects on the spreading and viability of plasmatocytes and granular cells only from the natural hosts, M. domestica and S. peregrina, little toxicity to cells from P. rapae and P. xuthus, and no effect on any of the other insects tested. Pteromalus puparum venom also apparently presented a high ability to block the spreading of Tn-5B1-4 cells derived from Trichoplusia ni, and high cytotoxicity to the cells and Ha cells derived from Helicoverpa armigera. Nasonia vitripennis venom, however, only had a marked lethal effect to Ha cells. In addition, the possibility that the host range of a defined parasitoid could be assessed using our method of treating hemocytes from candidate insects with venom in vitro, and the potential of our venoms tested in the development of bio-insecticides, insect-resistant transgenic plants, are discussed.

  18. High Expression of Cry1Ac Protein in Cotton (Gossypium hirsutum by Combining Independent Transgenic Events that Target the Protein to Cytoplasm and Plastids.

    Amarjeet Kumar Singh

    Full Text Available Transgenic cotton was developed using two constructs containing a truncated and codon-modified cry1Ac gene (1,848 bp, which was originally characterized from Bacillus thuringiensis subspecies kurstaki strain HD73 that encodes a toxin highly effective against many lepidopteran pests. In Construct I, the cry1Ac gene was cloned under FMVde, a strong constitutively expressing promoter, to express the encoded protein in the cytoplasm. In Construct II, the encoded protein was directed to the plastids using a transit peptide taken from the cotton rbcSIb gene. Genetic transformation experiments with Construct I resulted in a single copy insertion event in which the Cry1Ac protein expression level was 2-2.5 times greater than in the Bacillus thuringiensis cotton event Mon 531, which is currently used in varieties and hybrids grown extensively in India and elsewhere. Another high expression event was selected from transgenics developed with Construct II. The Cry protein expression resulting from this event was observed only in the green plant parts. No transgenic protein expression was observed in the non-green parts, including roots, seeds and non-green floral tissues. Thus, leucoplasts may lack the mechanism to allow entry of a protein tagged with the transit peptide from a protein that is only synthesized in tissues containing mature plastids. Combining the two events through sexual crossing led to near additive levels of the toxin at 4-5 times the level currently used in the field. The two high expression events and their combination will allow for effective resistance management against lepidopteran insect pests, particularly Helicoverpa armigera, using a high dosage strategy.

  19. Two Year Field Study to Evaluate the Efficacy of Mamestra brassicae Nucleopolyhedrovirus Combined with Proteins Derived from Xestia c-nigrum Granulovirus

    Chie Goto

    2015-03-01

    Full Text Available Japan has only three registered baculovirus biopesticides despite its long history of studies on insect viruses. High production cost is one of the main hindrances for practical use of baculoviruses. Enhancement of insecticidal effect is one possible way to overcome this problem, so there have been many attempts to develop additives for baculoviruses. We found that alkaline soluble proteins of capsules (GVPs of Xestia c-nigrum granulovirus can increase infectivity of some viruses including Mamestra brassicae nucleopolyhedrovirus (MabrNPV, and previously reported that MabrNPV mixed with GVPs was highly infectious to three important noctuid pests of vegetables in the following order, Helicoverpa armigera, M. brassicae, and Autographa nigrisigna. In this study, small-plot experiments were performed to assess concentrations of MabrNPV and GVPs at three cabbage fields and a broccoli field for the control of M. brassicae. In the first experiment, addition of GVPs (10 µg/mL to MabrNPV at 106 OBs/mL resulted in a significant increase in NPV infection (from 53% to 66%. In the second experiment, the enhancing effect of GVP on NPV infection was confirmed at 10-times lower concentrations of MabrNPV. In the third and fourth experiments, a 50% reduction in GVPs (from 10 µg/mL to 5 µg/mL did not result in a lowering of infectivity of the formulations containing MabrNPV at 105 OBs/mL. These results indicate that GVPs are promising additives for virus insecticides.

  20. The first report of Xenorhabdus indica from Steinernema pakistanense: co-phylogenetic study suggests co-speciation between X. indica and its steinernematid nematodes.

    Bhat, A H; Chaubey, A K; Půža, V

    2018-01-17

    During a survey in agricultural fields of the sub-humid region of Meerut district, India, two strains of entomopathogenic nematodes, labelled CS31 and CS32, were isolated using the Galleria baiting technique. Based on morphological and morphometric studies, and molecular data, the nematodes were identified as Steinernema pakistanense, making this finding the first report of this species from India. For the first time, we performed a molecular and biochemical characterization of the bacterial symbiont of S. pakistanense. Furthermore, a co-phylogenetic analysis of the bacteria from the monophyletic clade containing a symbiont of S. pakistanense, together with their nematode hosts, was conducted, to test the degree of nematode-bacteria co-speciation. Both isolates were also tested in a laboratory assay for pathogenicity against two major pests, Helicoverpa armigera and Spodoptera litura. The morphology of the Indian isolates corresponds mainly to the original description, with the only difference being the absence of a mucron in first-generation females and missing epiptygmata in the second generation. The sequences of bacterial recA and gyrB genes have shown that the symbiont of S. pakistanense is closely related to Xenorhabdus indica, which is associated with some other nematodes from the 'bicornutum' group. Co-phylogenetic analysis has shown a remarkable congruence between the nematode and bacterial phylogenies, suggesting that, in some lineages within the Steinernema / Xenorhabdus complex, the nematodes and bacteria have undergone co-speciation. In the virulence assay, both strains caused a 100% mortality of both tested insects after 48 h, even at the lowest doses of 25 infective juveniles per insect, suggesting that S. pakistanense could be considered for use in the biocontrol of these organisms in India.

  1. EVALUATION OF FOUR INTEGRATED PEST MANAGEMENT PACKAGES FOR CONTROLLING MAIN PESTS OF COTTON IN RAINFED FIELDS

    Nurindah Nurindah

    2014-04-01

    Full Text Available Cotton production nationally is low due to various constraints, including pests. Two main pests commonly found in cotton plantation in rain fed fields are cotton leafhopper (Amrasca biguttula and cotton bollworm (Helicoverpa armigera. The study aimed to evaluate four packages of integrated pest management (IPM techniques to control cotton leafhopper and cotton bollworm in rain fed fields. The experiment was conducted in farmers’ fields at Asembagus, East Java, between January and July 2012. Four packages of IPM evaluated were cotton varieties, i.e. Kanesia 10 or Kanesia 13, and seed treatment with synthetic insecticide (imidacloprid before sowing or spraying molasses (10 ml L-1 water as food for natural enemies. The cotton plants were intercropped with groundnut and sprayed with neem seed extract (NSE at the action threshold level for pest control. These packages were compared among themselves and also with the methods usually used by farmers, i.e. planting cotton variety Kanesia 8 intercropped with groundnut and pest control using synthetic chemical insecticides. Twenty five plants were sampled randomly per plot and measured for their growth, leafhopper and  bollworm populations, as well as cotton seed yield per plot. Observations were made weekly, starting at 30 days after planting (DAP until 120 DAP. The results showed that the use of Kanesia 10 or Kanesia 13 intercropped with groundnut and spraying molasses to conserve natural enemies was the best  pest management practice and superior to farmers’ practices. Conserving natural enemies is not only profitable (saving production cost of IDR1,150,000 to IDR1,500,000 ha-1 season-1, but also safe for the environment (no need to spray chemical insecticides.

  2. Non-recessive Bt toxin resistance conferred by an intracellular cadherin mutation in field-selected populations of cotton bollworm.

    Haonan Zhang

    Full Text Available Transgenic crops producing Bacillus thuringiensis (Bt toxins have been planted widely to control insect pests, yet evolution of resistance by the pests can reduce the benefits of this approach. Recessive mutations in the extracellular domain of toxin-binding cadherin proteins that confer resistance to Bt toxin Cry1Ac by disrupting toxin binding have been reported previously in three major lepidopteran pests, including the cotton bollworm, Helicoverpa armigera. Here we report a novel allele from cotton bollworm with a deletion in the intracellular domain of cadherin that is genetically linked with non-recessive resistance to Cry1Ac. We discovered this allele in each of three field-selected populations we screened from northern China where Bt cotton producing Cry1Ac has been grown intensively. We expressed four types of cadherin alleles in heterologous cell cultures: susceptible, resistant with the intracellular domain mutation, and two complementary chimeric alleles with and without the mutation. Cells transfected with each of the four cadherin alleles bound Cry1Ac and were killed by Cry1Ac. However, relative to cells transfected with either the susceptible allele or the chimeric allele lacking the intracellular domain mutation, cells transfected with the resistant allele or the chimeric allele containing the intracellular domain mutation were less susceptible to Cry1Ac. These results suggest that the intracellular domain of cadherin is involved in post-binding events that affect toxicity of Cry1Ac. This evidence is consistent with the vital role of the intracellular region of cadherin proposed by the cell signaling model of the mode of action of Bt toxins. Considered together with previously reported data, the results suggest that both pore formation and cell signaling pathways contribute to the efficacy of Bt toxins.

  3. Manthar-03: a high-yielding cultivar of wheat released for general cultivation in Southern Punjab

    Hussain, M.; Akhtar, L.H.; Nasim, M.

    2010-01-01

    We report the release of a new wheat variety Manthar-03. 'Manthar-03' is a high yielding and rust resistant variety of bread wheat with erect growth habit. It was released in the year 2003 as a general purpose variety. Manthar-03 is a selection from CIMMYT material (Entry No. 42 of 29 International Bread Wheat Screening Nursery) made at Regional Agricultural Research Institute (RARI), Bahawalpur during 1996-97. This strain has the famous CIMMYT line 'Kauz' in its parentage (KAUZ//ALTAR 84/AOS). Its pedigree is CM11163-6M-20Y-10M- 0M-0B. It is a more adapted and a high yielder. Genetically, this strain differs from existing commercial cultivars of Punjab. Resistance against leaf rust (5MRMS to 10MR), RRI value of 6.7 and 7.6 for leaf rust and ACI values of 3.4 and 0.7 for leaf rust) and high yield potential (6300 kg ha-1 ) are the major attributes of Manthar-03 that make it a superior variety for its target regions. Manthar-03 is tolerant to wheat aphid and Helicoverpa armigera. The thousand seed weight of this variety is 40-44 g. Seed is amber in color and contains 12.97% protein, 8.2% dry gluten and 1.55% ash. It has good chapati making quality. Plant type of Manthar-03 is erect with plant height 94 cm and droopy flag leaves. It is lodging resistant. It completes heading in 98 days and matures in 142 days. Manthar-03 performs better when planted from 15, November to 1, December, keeping 125 kg ha/sup -1/ seed rate and 125-85-50 kg NPK ha/sup -1/ are applied. (author)

  4. Effect of Iranian Bt cotton on life table of Bemisia tabaci (Hemiptera: Alyrodidae and Cry 1Ab detection in the whitefly honeydew

    Solmaz Azimi

    2016-09-01

    Full Text Available Transgenic cotton expressing the Cry 1Ab protein of Bacillus thuringiensis developing against Helocoverpa armigera may be affect on secondary pest such as Bemisia tabaci. In this study effects of Bt cotton on demographic parameters of B. tabaci were assessed and the data analyzed using the age specific, two-sex life table parameters. Results showed that getting to the adulthood stage, was faster on non-Bt cotton in comparison with Bt cotton. Also the fecundity was higher on non-Bt cotton than that on Bt cotton. Some of the population parameters (r, R0 and T of B. tabaci were affected by the Bt cotton significantly. The intrinsic rate of increase (r on Bt and non-Bt cotton was 0.07 day-1 and 0.1 day-1 , respectively. The net reproductive rate (R0 was 20.68 and 15.04 offspring/individual on Bt and non-Bt cotton, respectively. Mean generation time (T in non-Bt cotton was 27.22 and 34.62 days in Bt cotton. The results indicated that the life history of B. tabaci in the laboratory condition was influenced by host plant quality and Bt cotton was not a suitable host for B. tabaci. The western immunoblot method showed that the Cry protein detection in honeydew was positive which indicated that the Cry protein was ingested. Results revealed that the transgenic cotton could adversely affect the secondary pest and the natural enemies which feed on such pests as a host or their honeydew as a food source should be considered.

  5. Increased frequency of pink bollworm resistance to Bt toxin Cry1Ac in China.

    Peng Wan

    Full Text Available Transgenic crops producing insecticidal proteins from Bacillus thuringiensis (Bt kill some key insect pests, but evolution of resistance by pests can reduce their efficacy. The main approach for delaying pest adaptation to Bt crops uses non-Bt host plants as "refuges" to increase survival of susceptible pests. To delay evolution of pest resistance to transgenic cotton producing Bt toxin Cry1Ac, the United States and some other countries have required refuges of non-Bt cotton, while farmers in China have relied on "natural" refuges of non-Bt host plants other than cotton. The "natural" refuge strategy focuses on cotton bollworm (Helicoverpa armigera, the primary target of Bt cotton in China that attacks many crops, but it does not apply to another major pest, pink bollworm (Pectinophora gossypiella, which feeds almost entirely on cotton in China. Here we report data showing field-evolved resistance to Cry1Ac by pink bollworm in the Yangtze River Valley of China. Laboratory bioassay data from 51 field-derived strains show that the susceptibility to Cry1Ac was significantly lower during 2008 to 2010 than 2005 to 2007. The percentage of field populations yielding one or more survivors at a diagnostic concentration of Cry1Ac increased from 0% in 2005-2007 to 56% in 2008-2010. However, the median survival at the diagnostic concentration was only 1.6% from 2008 to 2010 and failure of Bt cotton to control pink bollworm has not been reported in China. The early detection of resistance reported here may promote proactive countermeasures, such as a switch to transgenic cotton producing toxins distinct from Cry1A toxins, increased planting of non-Bt cotton, and integration of other management tactics together with Bt cotton.

  6. High-efficiency Agrobacterium-mediated transformation of chickpea (Cicer arietinum L.) and regeneration of insect-resistant transgenic plants.

    Mehrotra, Meenakshi; Sanyal, Indraneel; Amla, D V

    2011-09-01

    To develop an efficient genetic transformation system of chickpea (Cicer arietinum L.), callus derived from mature embryonic axes of variety P-362 was transformed with Agrobacterium tumefaciens strain LBA4404 harboring p35SGUS-INT plasmid containing the uidA gene encoding β-glucuronidase (GUS) and the nptII gene for kanamycin selection. Various factors affecting transformation efficiency were optimized; as Agrobacterium suspension at OD(600) 0.3 with 48 h of co-cultivation period at 20°C was found optimal for transforming 10-day-old MEA-derived callus. Inclusion of 200 μM acetosyringone, sonication for 4 s with vacuum infiltration for 6 min improved the number of GUS foci per responding explant from 1.0 to 38.6, as determined by histochemical GUS assay. For introducing the insect-resistant trait into chickpea, binary vector pRD400-cry1Ac was also transformed under optimized conditions and 18 T(0) transgenic plants were generated, representing 3.6% transformation frequency. T(0) transgenic plants reflected Mendelian inheritance pattern of transgene segregation in T(1) progeny. PCR, RT-PCR, and Southern hybridization analysis of T(0) and T(1) transgenic plants confirmed stable integration of transgenes into the chickpea genome. The expression level of Bt-Cry protein in T(0) and T(1) transgenic chickpea plants was achieved maximum up to 116 ng mg(-1) of soluble protein, which efficiently causes 100% mortality to second instar larvae of Helicoverpa armigera as analyzed by an insect mortality bioassay. Our results demonstrate an efficient and rapid transformation system of chickpea for producing non-chimeric transgenic plants with high frequency. These findings will certainly accelerate the development of chickpea plants with novel traits.

  7. Whole genome re-sequencing reveals genome-wide variations among parental lines of 16 mapping populations in chickpea (Cicer arietinum L.).

    Thudi, Mahendar; Khan, Aamir W; Kumar, Vinay; Gaur, Pooran M; Katta, Krishnamohan; Garg, Vanika; Roorkiwal, Manish; Samineni, Srinivasan; Varshney, Rajeev K

    2016-01-27

    Chickpea (Cicer arietinum L.) is the second most important grain legume cultivated by resource poor farmers in South Asia and Sub-Saharan Africa. In order to harness the untapped genetic potential available for chickpea improvement, we re-sequenced 35 chickpea genotypes representing parental lines of 16 mapping populations segregating for abiotic (drought, heat, salinity), biotic stresses (Fusarium wilt, Ascochyta blight, Botrytis grey mould, Helicoverpa armigera) and nutritionally important (protein content) traits using whole genome re-sequencing approach. A total of 192.19 Gb data, generated on 35 genotypes of chickpea, comprising 973.13 million reads, with an average sequencing depth of ~10 X for each line. On an average 92.18 % reads from each genotype were aligned to the chickpea reference genome with 82.17 % coverage. A total of 2,058,566 unique single nucleotide polymorphisms (SNPs) and 292,588 Indels were detected while comparing with the reference chickpea genome. Highest number of SNPs were identified on the Ca4 pseudomolecule. In addition, copy number variations (CNVs) such as gene deletions and duplications were identified across the chickpea parental genotypes, which were minimum in PI 489777 (1 gene deletion) and maximum in JG 74 (1,497). A total of 164,856 line specific variations (144,888 SNPs and 19,968 Indels) with the highest percentage were identified in coding regions in ICC 1496 (21 %) followed by ICCV 97105 (12 %). Of 539 miscellaneous variations, 339, 138 and 62 were inter-chromosomal variations (CTX), intra-chromosomal variations (ITX) and inversions (INV) respectively. Genome-wide SNPs, Indels, CNVs, PAVs, and miscellaneous variations identified in different mapping populations are a valuable resource in genetic research and helpful in locating genes/genomic segments responsible for economically important traits. Further, the genome-wide variations identified in the present study can be used for developing high density SNP arrays for

  8. c-di-GMP Regulates Various Phenotypes and Insecticidal Activity of Gram-Positive Bacillus thuringiensis

    Yang Fu

    2018-02-01

    Full Text Available C-di-GMP has been well investigated to play significant roles in the physiology of many Gram-negative bacteria. However, its effect on Gram-positive bacteria is less known. In order to more understand the c-di-GMP functions in Gram-positive bacteria, we have carried out a detailed study on the c-di-GMP-metabolizing enzymes and their physiological functions in Bacillus thuringiensis, a Gram-positive entomopathogenic bacterium that has been applied as an insecticide successfully. We performed a systematic study on the ten putative c-di-GMP-synthesizing enzyme diguanylate cyclases (DGCs and c-di-GMP-degrading enzyme phosphodiesterases (PDEs in B. thuringiensis BMB171, and artificially elevated the intracellular c-di-GMP level in BMB171 by deleting one or more pde genes. We found increasing level of intracellular c-di-GMP exhibits similar activities as those in Gram-negative bacteria, including altered activities in cell motility, biofilm formation, and cell-cell aggregation. Unexpectedly, we additionally found a novel function exhibited by the increasing level of c-di-GMP to promote the insecticidal activity of this bacterium against Helicoverpa armigera. Through whole-genome transcriptome profile analyses, we found that 4.3% of the B. thuringiensis genes were differentially transcribed when c-di-GMP level was increased, and 77.3% of such gene products are involved in some regulatory pathways not reported in other bacteria to date. In summary, our study represents the first comprehensive report on the c-di-GMP-metabolizing enzymes, their effects on phenotypes, and the transcriptome mediated by c-di-GMP in an important Gram-positive bacterium.

  9. Contributions of gut bacteria to Bacillus thuringiensis-induced mortality vary across a range of Lepidoptera

    Holt Jonathan

    2009-03-01

    Full Text Available Abstract Background Gut microbiota contribute to the health of their hosts, and alterations in the composition of this microbiota can lead to disease. Previously, we demonstrated that indigenous gut bacteria were required for the insecticidal toxin of Bacillus thuringiensis to kill the gypsy moth, Lymantria dispar. B. thuringiensis and its associated insecticidal toxins are commonly used for the control of lepidopteran pests. A variety of factors associated with the insect host, B. thuringiensis strain, and environment affect the wide range of susceptibilities among Lepidoptera, but the interaction of gut bacteria with these factors is not understood. To assess the contribution of gut bacteria to B. thuringiensis susceptibility across a range of Lepidoptera we examined larval mortality of six species in the presence and absence of their indigenous gut bacteria. We then assessed the effect of feeding an enteric bacterium isolated from L. dispar on larval mortality following ingestion of B. thuringiensis toxin. Results Oral administration of antibiotics reduced larval mortality due to B. thuringiensis in five of six species tested. These included Vanessa cardui (L., Manduca sexta (L., Pieris rapae (L. and Heliothis virescens (F. treated with a formulation composed of B. thuringiensis cells and toxins (DiPel, and Lymantria dispar (L. treated with a cell-free formulation of B. thuringiensis toxin (MVPII. Antibiotics eliminated populations of gut bacteria below detectable levels in each of the insects, with the exception of H. virescens, which did not have detectable gut bacteria prior to treatment. Oral administration of the Gram-negative Enterobacter sp. NAB3, an indigenous gut resident of L. dispar, restored larval mortality in all four of the species in which antibiotics both reduced susceptibility to B. thuringiensis and eliminated gut bacteria, but not in H. virescens. In contrast, ingestion of B. thuringiensis toxin (MVPII following antibiotic

  10. A moth pheromone brewery: production of (Z)-11-hexadecenol by heterologous co-expression of two biosynthetic genes from a noctuid moth in a yeast cell factory.

    Hagström, Åsa K; Wang, Hong-Lei; Liénard, Marjorie A; Lassance, Jean-Marc; Johansson, Tomas; Löfstedt, Christer

    2013-12-13

    Moths (Lepidoptera) are highly dependent on chemical communication to find a mate. Compared to conventional unselective insecticides, synthetic pheromones have successfully served to lure male moths as a specific and environmentally friendly way to control important pest species. However, the chemical synthesis and purification of the sex pheromone components in large amounts is a difficult and costly task. The repertoire of enzymes involved in moth pheromone biosynthesis in insecta can be seen as a library of specific catalysts that can be used to facilitate the synthesis of a particular chemical component. In this study, we present a novel approach to effectively aid in the preparation of semi-synthetic pheromone components using an engineered vector co-expressing two key biosynthetic enzymes in a simple yeast cell factory. We first identified and functionally characterized a ∆11 Fatty-Acyl Desaturase and a Fatty-Acyl Reductase from the Turnip moth, Agrotis segetum. The ∆11-desaturase produced predominantly Z11-16:acyl, a common pheromone component precursor, from the abundant yeast palmitic acid and the FAR transformed a series of saturated and unsaturated fatty acids into their corresponding alcohols which may serve as pheromone components in many moth species. Secondly, when we co-expressed the genes in the Brewer's yeast Saccharomyces cerevisiae, a set of long-chain fatty acids and alcohols that are not naturally occurring in yeast were produced from inherent yeast fatty acids, and the presence of (Z)-11-hexadecenol (Z11-16:OH), demonstrated that both heterologous enzymes were active in concert. A 100 ml batch yeast culture produced on average 19.5 μg Z11-16:OH. Finally, we demonstrated that oxidized extracts from the yeast cells containing (Z)-11-hexadecenal and other aldehyde pheromone compounds elicited specific electrophysiological activity from male antennae of the Tobacco budworm, Heliothis virescens, supporting the idea that genes from different

  11. Antennal transcriptome analysis and comparison of olfactory genes in two sympatric defoliators, Dendrolimus houi and Dendrolimus kikuchii (Lepidoptera: Lasiocampidae).

    Zhang, Sufang; Zhang, Zhen; Wang, Hongbin; Kong, Xiangbo

    2014-09-01

    The Yunnan pine and Simao pine caterpillar moths, Dendrolimus houi Lajonquière and Dendrolimus kikuchii Matsumura (Lepidoptera: Lasiocampidae), are two closely related and sympatric pests of coniferous forests in southwestern China, and olfactory communication systems of these two insects have received considerable attention because of their economic importance. However, there is little information on the molecular aspect of odor detection about these insects. Furthermore, although lepidopteran species have been widely used in studies of insect olfaction, few work made comparison between sister moths on the olfactory recognition mechanisms. In this study, next-generation sequencing of the antennal transcriptome of these two moths were performed to identify the major olfactory genes. After comparing the antennal transcriptome of these two moths, we found that they exhibit highly similar transcripts-associated GO terms. Chemosensory gene families were further analyzed in both species. We identified 23 putative odorant binding proteins (OBP), 17 chemosensory proteins (CSP), two sensory neuron membrane proteins (SNMP), 33 odorant receptors (OR), and 10 ionotropic receptors (IR) in D. houi; and 27 putative OBPs, 17 CSPs, two SNMPs, 33 ORs, and nine IRs in D. kikuchii. All these transcripts were full-length or almost full-length. The predicted protein sequences were compared with orthologs in other species of Lepidoptera and model insects, including Bombyx mori, Manduca sexta, Heliothis virescens, Danaus plexippus, Sesamia inferens, Cydia pomonella, and Drosophila melanogaster. The sequence homologies of the orthologous genes in D. houi and D. kikuchii are very high. Furthermore, the olfactory genes were classed according to their expression level, and the highly expressed genes are our target for further function investigation. Interestingly, many highly expressed genes are ortholog gene of D. houi and D. kikuchii. We also found that the Classic OBPs were

  12. Functional Analysis of Polyphenol Oxidases by Antisense/Sense Technology

    Jutharat Attajarusit

    2007-07-01

    Full Text Available Polyphenol oxidases (PPOs catalyze the oxidation of phenolics to quinones, the secondary reactions of which lead to oxidative browning and postharvest losses of many fruits and vegetables. PPOs are ubiquitous in angiosperms, are inducible by both biotic and abiotic stresses, and have been implicated in several physiological processes including plant defense against pathogens and insects, the Mehler reaction, photoreduction of molecular oxygen by PSI, regulation of plastidic oxygen levels, aurone biosynthesis and the phenylpropanoid pathway. Here we review experiments in which the roles of PPO in disease and insect resistance as well as in the Mehler reaction were investigated using transgenic tomato (Lycopersicon esculentum plants with modified PPO expression levels (suppressed PPO and overexpressing PPO. These transgenic plants showed normal growth, development and reproduction under laboratory, growth chamber and greenhouse conditions. Antisense PPO expression dramatically increased susceptibility while PPO overexpression increased resistance of tomato plants to Pseudomonas syringae. Similarly, PPO-overexpressing transgenic plants showed an increase in resistance to various insects, including common cutworm (Spodoptera litura (F., cotton bollworm (Helicoverpa armigera (Hübner and beet army worm (Spodoptera exigua (Hübner, whereas larvae feeding on plants with suppressed PPO activity had higher larval growth rates and consumed more foliage. Similar increases in weight gain, foliage consumption, and survival were also observed with Colorado potato beetles (Leptinotarsa decemlineata (Say feeding on antisense PPO transgenic tomatoes. The putative defensive mechanisms conferred by PPO and its interaction with other defense proteins are discussed. In addition, transgenic plants with suppressed PPO exhibited more favorable water relations and decreased photoinhibition compared to nontransformed controls and transgenic plants

  13. LANDSCAPE CHANGES IN A LOWLAND IN BENIN: ECOLOGICAL IMPACT ON PESTS AND NATURAL ENEMIES.

    Boucher, A; Silvie, P; Menozzi, P; Adda, C; Auzoux, S; Jean, J; Huat, J

    2015-01-01

    Habitat management involving conservative biological control could be a good crop pest management option in poor African countries. A survey was conducted from August 2013 to July 2014 in a rainfed lowland region near Pélébina, northern Benin, in order to characterize spatiotemporal landscape changes and investigate their influence on the main crop pests and their associated natural enemies. The area was mapped mainly regarding crop fields and fallows. Visual observations were recorded and a database was compiled. Major landscape composition changes were noted between rainy and dry seasons, which affected the presence of both pests and natural enemies. Cereals (rice, maize and sorghum) and cotton were grown in the humid season, and then okra (Abelmoschus esculentus) was the dominant vegetable crop in dry season. These modifications impacted fallow abundance throughout the lowland. Different cotton (e.g. Helicoverpa armigera, Dysdercus sp., Zonocerus variegatus) or rice (e.g. Diopsis longicornis, D. apicalis) pests were observed during dry season in okra crops. Dry season surveys of Poaceae in two types of fallows ('humid', 'dry') revealed the presence of very few stem borers: only 0.04% of stems sampled were infested by stem borers, with a mean of 1.13 larvae per stem. Known cereal stem borer species such as Busseola fusco, Coniesta ignefusalis, Sesamia calamistis were not clearly identified among these larvae because of their diapausing stage and white color. Unexpected pollinators (Hymenoptera Apidae, genus Braunsapis, Ceratina and Xylocopa) and predators (Crabronidae, genus Dasyproctus) were found in the stems. Sweep-net collection of insects in humid fallows allowed us to describe for the first time in Benin seven Diopsidae species (23% of adults bearing Laboulbeniomycetes ectoparasitic fungi). Some of these species were captured in rice fields during rainy season. Parasitoids (adult Chalcidoidae and Ichneumonoidae) were observed during both seasons but their

  14. Management of lepidopterans through irradiations

    Bhati, Dheeraj; Parvez, Asif; Kausar, Hina; Srivastava, Meera

    2012-01-01

    suppression by irradiation include Spodoptera litura, S.exigua, S.frugiperda, Helicoverpa armigera, H.zea, Pectinophora gossypiella, Diatraea saccharalis, Cydia pomonella, C.molesta, Ectomyelois ceratoniae, Ephestia kuehniella, Crocidolomia binotalis, Chilo suppressalis, Ostrinia furnacalis, O.nubilalis, Plutella xylostella and Spilosoma obliqua. (author)

  15. Influence of cover crops on insect pests and predators in conservation tillage cotton.

    Tillman, Glynn; Schomberg, Harry; Phatak, Sharad; Mullinix, Benjamin; Lachnicht, Sharon; Timper, Patricia; Olson, Dawn

    2004-08-01

    In fall 2000, an on-farm sustainable agricultural research project was established for cotton, Gossypium hirsutum L., in Tift County, Georgia. The objective of our 2-yr research project was to determine the impact of several cover crops on pest and predator insects in cotton. The five cover crop treatments included 1) cereal rye, Secale cereale L., a standard grass cover crop; 2) crimson clover, Trifolium incarnatum L., a standard legume cover crop; 3) a legume mixture of balansa clover, Trifolium michelianum Savi; crimson clover; and hairy vetch, Vicia villosa Roth; 4) a legume mixture + rye combination; and 5) no cover crop in conventionally tilled fields. Three main groups or species of pests were collected in cover crops and cotton: 1) the heliothines Heliothis virescens (F.) and Helicoverpa zea (Boddie); 2) the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois); and 3) stink bugs. The main stink bugs collected were the southern green stink bug, Nezara viridula (L.); the brown stink bug, Euschistus servus (Say); and the green stink bug, Acrosternum hilare (Say). Cotton aphids, Aphis gossypii Glover, were collected only on cotton. For both years of the study, the heliothines were the only pests that exceeded their economic threshold in cotton, and the number of times this threshold was exceeded in cotton was higher in control cotton than in crimson clover and rye cotton. Heliothine predators and aphidophagous lady beetles occurred in cover crops and cotton during both years of the experiment. Geocoris punctipes (Say), Orius insidiosus (Say), and red imported fire ant, Solenopsis invicta Buren were relatively the most abundant heliothine predators observed. Lady beetles included the convergent lady beetle, Hippodamia convergens Guérin-Méneville; the sevenspotted lady beetle, Coccinella septempunctata L.; spotted lady beetle, Coleomegilla maculata (DeGeer); and the multicolored Asian lady beetle, Harmonia axyridis (Pallas). Density of G. punctipes was

  16. Summary of Session 1 'Lessons from 2011'

    Lamont, M; Bracco, C

    2012-01-01

    Review of 2011 LHC Run from The Experiments Perspective, M. Ferro-Luzzi (PH-LBD): M. Ferro-Luzzi highlighted the excellent performance of the machine and the experiments in 2011 and the fast and impressive achievements both when operating with protons and Pb ions. In a month the same luminosity as during the full 2010 proton run was delivered, and a factor 16 higher luminosity was produced with Pb ions. The excellent machine performance allowed ATLAS and CMS to make interesting observations in the context of the Higgs’ boson search and LHCb found some evidence of CP violation in time-integrated D0 which could open the way for a new physics. Input from Evian, M. Lamont (BE-OP): M. Lamont presented a summary of what discussed in Evian about lessons learnt during 2011 operation and improvements foreseen for 2012. He underlined that 2011 was a remarkable year with a continuously faster increase in luminosity production and without real show stoppers. The machinewas characterized by operational robustness, a good reproducibility, stability, beam lifetime, optics control and an excellent performance of the Machine Protection system (MPs) and of the injectors. The 2011 Run: Availability Analysis, A. Macpherson (BE-OP): A. Macpherson spoke about machine availability in 2011 and gave some statistics of fills for p-p and Pb-Pb runs. He calculated a machine availability of 76.7% and that 33% of the operation time was spent in stable beam. The Hubner factor, which gives an estimate of the luminosity production duration, was slightly bigger than the expected 0.2 value both for the proton (0.22) and lead ion (0.24) runs. Stable beams lasted in average ∼6 hours but about 50% of the fills were shorter than 4 hours. Injection and Lessons for 2012, C. Bracco (TE-ABT): C. Bracco made a presentation on the performance of the injection system. The injection of 144 bunches became fully operational in 2011 in agreement with what predicted during the last Chamonix workshop. Moreover

  17. Summary of Session 1 'Lessons from 2011'

    Lamont, M; Bracco, C [European Organization for Nuclear Research, Geneva (Switzerland)

    2012-07-01

    Review of 2011 LHC Run from The Experiments Perspective, M. Ferro-Luzzi (PH-LBD): M. Ferro-Luzzi highlighted the excellent performance of the machine and the experiments in 2011 and the fast and impressive achievements both when operating with protons and Pb ions. In a month the same luminosity as during the full 2010 proton run was delivered, and a factor 16 higher luminosity was produced with Pb ions. The excellent machine performance allowed ATLAS and CMS to make interesting observations in the context of the Higgs’ boson search and LHCb found some evidence of CP violation in time-integrated D0 which could open the way for a new physics. Input from Evian, M. Lamont (BE-OP): M. Lamont presented a summary of what discussed in Evian about lessons learnt during 2011 operation and improvements foreseen for 2012. He underlined that 2011 was a remarkable year with a continuously faster increase in luminosity production and without real show stoppers. The machinewas characterized by operational robustness, a good reproducibility, stability, beam lifetime, optics control and an excellent performance of the Machine Protection system (MPs) and of the injectors. The 2011 Run: Availability Analysis, A. Macpherson (BE-OP): A. Macpherson spoke about machine availability in 2011 and gave some statistics of fills for p-p and Pb-Pb runs. He calculated a machine availability of 76.7% and that 33% of the operation time was spent in stable beam. The Hubner factor, which gives an estimate of the luminosity production duration, was slightly bigger than the expected 0.2 value both for the proton (0.22) and lead ion (0.24) runs. Stable beams lasted in average ∼6 hours but about 50% of the fills were shorter than 4 hours. Injection and Lessons for 2012, C. Bracco (TE-ABT): C. Bracco made a presentation on the performance of the injection system. The injection of 144 bunches became fully operational in 2011 in agreement with what predicted during the last Chamonix workshop. Moreover

  18. Effect of Different Diets of Flour Moth on its Parasitoid Wasp Fitness, Trichogramma brassicae (Hym.:Trichogrammatidae

    Paria Soltaninejad

    2017-03-01

    Full Text Available Introduction: Parasitoid wasp, Trichogramma brassicae (Bezdenko (Hym.: Trichogrammatidae has excellent position in mass production technology, scope of application, wide geographical distribution and unmatched talent to adapt to different climatic conditions that can be easily reared on Mediterranean flour moth (MFM, Ephestia kuehniella Zeller (Lep.: Pyralidae. The parasitoid use is in order to control Chilo suppressalis (Walker (Lep.: Pyralidae, Helicoverpa armigera (Lep.: Noctuidae, Ostrinia nubilalis (Hübner (Lep.: Pyralidae, Ectomyelois ceratoniae (Zeller (Lep.: Phycitidae and Cydia pomonella (Lep.: Tortricidae (38. The studies have been shown that the quantity and quality of the host diet affect growth period, size of adults, adult longevity, fecundity and sex ratio of the parasitoid. The objective of current research was to evaluate the effect of four different MFM diets on the fitness of second and forth generations of the parasitoid wasp, T. brassicae. Materials and Methods: The four diets ((I wheat flour, wheat bran, corn flour, bread yeast and glycerin; (II wheat flour, wheat bran, barley flour, bread yeast and glycerin; (III barley flour, bread yeast and glycerin and (IV wheat flour, barley flour and corn flour were sterilized at 51 °C for 24 hours. After cooling at ambient temperature, the diets were contaminated with the eggs of MFM and then were maintained at 25±1° C, 60±5 % RH and a photoperiod of 14 L: 10 D. The MFM adults emerged after 35 to 40 days and their eggs were collected daily to use for investigation of the parasitoid biology. For rearing the parasitoid wasps on the MFM eggs obtained from each diet, some cards containing the parasitoid pre-pupae were put inside cages (25 × 25 × 25 cm and reared for one generation. The adults were fed honey (20% for one day and then were provided with one-day-old sterile MFM eggs. To prevent egg hatching and sterile them, they were kept at 15°C for four h. The tests were