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1.
J Insect Sci ; 20(6)2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33232487

RESUMO

Bacillus thuringiensis Berliner subsp. kurstaki (Btk) and Habrobracon hebetor Say are both biological control agents of Helicoverpa armigera Hubner. The present study evaluated their compatibility for combined application against this pest by examining the acceptability of Btk-inoculated hosts for H. hebetor females and testing for negative life-history impacts on developing progeny. Second-instar H. armigera larvae fed for 72 h on potted chickpea plants treated with three concentrations of Btk (LC15, LC35, and LC70) and were then used in bioassays of parasitoid development and parasitism behavior. Survival of parasitoids was significantly reduced, and immature development prolonged, on hosts fed chickpea plants treated with LC35 and LC70  Btk, but not on plants treated with LC15  Btk. Parasitoids failed to discriminate against hosts treated with LC15 or LC35  Btk in choice tests, but attacked fewer hosts treated with LC70  Btk, paralyzing and parasitizing more healthy hosts, and laying more eggs on them. In contrast, a no-choice test revealed that more hosts treated with LC35 and LC70  Btk were paralyzed compared with control or LC15-treated hosts, but the numbers of hosts parasitized and eggs laid did not vary among Btk treatments. Thus, females required an experience with healthy hosts, as they had in the choice test, to discriminate against diseased ones. We conclude that H. hebetor and Btk are compatible for joint application against H. armigera, which could potentially improve biological control of this pest.


Assuntos
Bacillus thuringiensis/química , Interações Hospedeiro-Parasita , Controle de Insetos , Mariposas/parasitologia , Controle Biológico de Vetores , Vespas/fisiologia , Animais , Feminino , Larva/crescimento & desenvolvimento , Larva/parasitologia , Mariposas/crescimento & desenvolvimento , Vespas/crescimento & desenvolvimento
2.
J Econ Entomol ; 113(4): 1648-1655, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32270869

RESUMO

Cotton bollworm, Helicoverpa armigera Hubner, is a cosmopolitan polyphagous pest of many crops. Habrobracon hebetor Say and Helicoverpa armigera nucleopolyhedrovirus (HearNPV) are two important biocontrol agents used to manage this pest, sometimes in combination. We evaluated the sublethal effects of HearNPV on H. hebetor life table parameters under laboratory conditions when its host (second instar H. armigera) was treated with HearNPV, and tested H. hebetor females for their ability to discriminate against inoculated hosts. Emergence of adults reared as solitary larvae was reduced by half on LC30-inoculated larvae compared to controls, but not on LC5 or LC15-inoculated hosts. Low concentrations (LC5, LC15, and LC30) of HearNPV had no effects on overall parasitoid developmental time, but longevity and lifetime fecundity was reduced for females emerging from hosts receiving the LC30 treatment. Net reproductive rate (R0), intrinsic rate of increase (rm), and finite rate of increase (λ) were all decreased in a concentration-dependent manner in the LC15 and LC30 treatments, as were female life expectancy, age-specific survivorship (lx), and age-specific fecundity (mx), whereas population doubling time (DT) increased. Parasitoids did not discriminate against LC15-inoculated larvae in choice or no-choice tests, but parasitized more LC50-inoculated hosts than controls in the choice test, with no significant differences in total numbers of eggs laid in either case. Although parasitoids suffered some loss of fitness in HearNPV-inoculated hosts under these laboratory conditions, these agents still appear compatible for joint application against H. armigera under field conditions, provided parasitoid releases are made 2 d after NPV application.


Assuntos
Mariposas , Nucleopoliedrovírus , Animais , Feminino , Larva , Controle Biológico de Vetores
3.
J Biomol Struct Dyn ; 35(2): 343-353, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26924613

RESUMO

Aptamers (ss-DNA or ss-RNA), also known as artificial antibodies, have been selected in vitro median to bind target molecules with high affinity and selectivity. Diazinon is one of the most widely used organophosphorus insecticides in developing and underdeveloped countries as insecticide and acaricide. Diazinon is readily absorbed from the gastrointestinal system and rapidly distributed throughout the body. Thus, the design of clinical and laboratory diagnostics using nanobiosensors is necessary. A computational approach allows us to screen or rank receptor structure and predict interaction outcomes with a deeper understanding, and it is much more cost effective than laboratory attempts. In this research, the best sequence (high affinity bind Diazinon-ssDNA) was ranked among 12 aptamers isolated from SELEX experimentation. Docking results, as the first virtual screening stage and static technique, selected frequent conformation of each aptamer. Then, the quantity and quality of aptamer-Diazinon interaction were simulated using molecular dynamics as a mobility technique. RMSD, RMSF, radius of gyration, and the number of hydrogen bonds formed between Diazinon-aptamer were monitored to assess the quantity and quality of interactions. G-quadruplex DNA aptamer (DF20) showed to be a reliable candidate for Diazinon biosensing. The apta-nanosensor designed using simulation results allowed with linearity detection in the range of .141-.65 nM and a LOD of 17.903 nM, and it was validated using a computational molecular approach.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Diazinon/química , Simulação de Dinâmica Molecular , Nanotecnologia , DNA/química , Ligação de Hidrogênio , Inseticidas/química , Nanopartículas Metálicas , Conformação Molecular , Simulação de Acoplamento Molecular , Prata/química
4.
Zootaxa ; 4072(2): 291-300, 2016 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-27395925

RESUMO

A new species of Hexabdella Van der Schyff, Theron & Ueckermann (Acariformes: Bdellidae), H. quercusi Eghbalian, Khanjani, Safaralizadeh, Ueckermann sp. nov., and a new species of Neomolgus Oudemans, N. iraniensis Eghbalian, Khanjani, Safaralizadeh, Ueckermann sp. nov., are described and illustrated. A key is provided for adult females of all known species of Hexabdella, as well as for adult females of Neomolgus from Asian and neighbouring countries, including Iran, Japan and the Siberian region of Russia. All specimens were collected from soil and litter under oak trees, Quercus brantii Lindley (Fagaceae), or from soil and litter under wild almond, Amygdalus scoparia L. (Rosaceae), from western Iran.


Assuntos
Ácaros/anatomia & histologia , Ácaros/classificação , Animais , Ecossistema , Feminino , Irã (Geográfico) , Solo
5.
J Biomol Struct Dyn ; 34(11): 2505-17, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26609886

RESUMO

Pesticide detection is a main concern of food safety experts. Therefore, it is urgent to design an accurate, rapid, and cheap test. Biosensors that detect pesticide residues could replace current methods, such as HPLC or GC-MC. This research designs a biosensor based on aptamer (Oligonucleotide ss-DNA) in the receptor role, silver nanoparticles (AgNPs) as optical sensors and salt (NaCl) as the aggregative inducer of AgNPs to detect the presence of Acetamiprid. After optimization, .6 µM aptamer and 100 mM salt were employed. The selectivity and sensitivity of the complex were examined by different pesticides and different Acetamiprid concentrations. To simulate in vitro experimental conditions, bioinformatics software was used as in silico analysis. The results showed the detection of Acetamiprid at the .02 ppm (89.8 nM) level in addition to selectivity. Docking outputs introduced two loops as active sites in aptamer and confirmed aptamer-Acetamiprid bonding. Circular dichroism spectroscopy (CD) confirmed upon Acetamiprid binding, aptamer was folded due to stem-loop formation. Stability of the Apt-Acetamiprid complex in a simulated aqueous media was examined by molecular dynamic studies.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Nanopartículas Metálicas/química , Piridinas/química , Dicroísmo Circular , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Nanotecnologia , Neonicotinoides , Prata , Relação Estrutura-Atividade
6.
Zootaxa ; 3847(4): 567-75, 2014 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-25112359

RESUMO

This paper reports two new species of Bdellidae, Cyta leliae sp. nov. and Cyta kurdistanicus sp. nov., collected from soil and litter under oak trees, Quercus brantii Lindl. (Fagaceae), wild almond, Amygdalus lycioides Spach (Rosaceae) and grass, Kurdistan Province, Iran. A key is provided to adult female Cyta of the world. 


Assuntos
Ácaros/classificação , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Feminino , Irã (Geográfico) , Masculino , Ácaros/anatomia & histologia , Ácaros/crescimento & desenvolvimento , Tamanho do Órgão
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