Effect of entomopathogenic nematode, Steinernema feltiae , on survival and plasma phenoloxidase activity of Helicoverpa armigera (Hb) (Lepidoptera: Noctuidae) in laboratory conditions

Egyptian Journal of Biological Pest Control

Gary Brian Dunphy¹  Laleh Ebrahimi²  Mohammadreza Shiri³ 

[1] Department of Natural Resource Sciences, McGill University, Quebec, Canada;Plant Protection Research Department, Ardabil Agricultural and Natural Resources Research and Education Center, AREEO, Moghan, Iran;Seed and Plant Improvement Institute, Agricultural Research Education and Extension Organization (AREEO), Karaj, Iran

关键词: Cotton bollworm;    Immunity;    LC50;    Phenoloxidase;   

DOI  :  10.1186/s41938-017-0016-x

学科分类：动物科学

来源: Springer

【 摘 要 】

Lethal effect of the entomopathogenic nematode, Steinernema feltiae, against prepupae of Helicoverpa armigera (Hb) (Lepidoptera: Noctuidae) in soil was evaluated. Plasma phenoloxidase activity of H. armigera prepupae against S. feltiae also was evaluated. In brief, 20–25 infective juveniles (IJs) of S. feltiae in 20 μl Ringer’s solution were injected into the hemolymph of H. armigera prepupae in different time intervals. In order to evaluate the effect of the Ringer’s solution, it was also injected into the larvae in a separate experiment as positive control. A third group of non-injected insects was used as negative control. Hemolymph of the insects was collected in different time intervals (0 to 24 h post injection). Phenoloxidase (PO) activity of H. armigera hemolymph was determined spectrophotometrically, using l-Dopa as substrate. The LC20, LC50, and LC80 values were 4.5, 19, and 76 IJs per insect, respectively. PO activity assay demonstrated higher levels of PO unit in nematode-injected insects compared to control groups. Nematode-injected insects showed the highest plasma PO activity 8 h post-injection.

【 授权许可】

CC BY