Journal of Economic Entomology (2020) 113, 2086-2095

Bita Valizadeh, Samira Samarfard, Jalal Jalali Sendi and Thomas P. Karbanowicz (2020)
Developing an Ephestia kuehniella hemocyte cell line to assess the bio-insecticidal potential of microencapsulated Helicoverpa armigera Nucleopolyhedrovirus against cotton bollworm (Lepidoptera: Noctuidae) larva
Journal of Economic Entomology 113 (5), 2086-2095
Abstract: Helicoverpa armigera Nucleopolyhedrovirus (HearNPV) (genus: Alphabaculovirus, incertae sedis: Baculoviridae) has been used to control Helicoverpa armigera (Hübner). A reproducible and susceptible cell line was prepared from the hemocytes of Ephestia kuehniella in Grace and Ex-Cell 420 media. The population doubling time of these cloned cell cultures during the logarithmic phase were about 2.3 and 3.7 d for Ex-Cell 420 and Grace's media, respectively. When 60% confluence occurred, cells were infected by viral inoculums. All biochemical compounds were significantly changed relevant to cellular metabolism due to HearNPV infection. In order to improve its stability, two polymer formulations were used, i.e., formulation A (sodium alginate, gelatin, starch, and molasses) and formulation B (cottonseed kernel extract, Bran, glycerol, boric acid, egg white, and sugar). Formulant A provided high photostability by exhibiting 83.2 ± 3% efficacy and 88.66 ± 2.1% original activities remaining after 72 h UV exposure. Percentage original activity remaining of unformulated HearNPV and formulated mixture of B was 38.66 ± 2.6% and 9.33 ± 1.3%, respectively, after 72 h UV-irradiation. The virulence of the HearNPV proliferated from the Ex-Cell medium was similar to the virulence of wild-type HearNPV with LC₅₀ of 7.7×10⁵ OBs/ml. Formulant A, revealed only 20.0 ± 1% reduction in efficacy while the unformulated virus and formulant B faced a reduction of 90.0 ± 3% and 64.0 ± 2% after 72 h of UVA irradiation. Formulant A thus showed a high potential to protect HearNPVs microparticles against UV-inactivation suggesting a new platform for more efficient biological-management of cotton bollworm (specific name Helicoverpa armigera, genus: Helicoverpa, Lepidoptera: Noctuidae) in vivo.
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Link to article at publishers website
Database assignments for author(s): Jalal Jalali Sendi

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
formulation/storage of bioagents
formulation/storage of bioagents

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Helicoverpa armigera
Alphabaculovirus helarmigerae (entomopathogen)	Helicoverpa armigera