title: Effect of azadirachtin on acetylcholinesterase (AChE) activity and histology of the brown planthopper Nilaparvata lugens (Stål).
abstract: The effect of azadirachtin (AZA), a tetranortriterpene from neem, on the mortality, acetylcholinesterase (AChE) activity, and the development of the ovaries of female brown planthopper (BPH), Nilaparvata lugens (Stål) was tested in laboratory experiments. The lethal concentrations were determined and applied topically to the adult female BPH (LC(50)=0.47 ppm and LC(90)=0.96 ppm). The treated insects exhibited toxic symptoms with a dose-dependent mortality. The LC(50) concentrations were tested against AChE activity of the BPH. The results indicate that AZA significantly inhibits the activity of AChE only at the high dose (P<.0001) compared with control. Adult females that were exposed to AZA showed a significant reduction in weight (23%, 40%, and 64% for 0.1, 0.25, and 0.5 ppm, respectively). Fecundity was also significantly reduced in AZA treatments compared to the control. Histological study of ovary sections revealed abnormalities in follicular epithelial cells due to AZA treatment.
authors.affiliation: Plant Environment Division, Honam Agricultural Research Institute, National Institute of Crop Science, Rural Development Administration, Iksan, Chonbuk 570-080, Republic of Korea. senthilkalaidr@hotmail.com
authors.forename: Sengottayan
authors.initials: S
authors.lastname: Senthil Nathan
authors.forename: Man
authors.initials: M
authors.lastname: Young Choi
authors.forename: Hong
authors.initials: H
authors.lastname: Yul Seo
authors.forename: Chae
authors.initials: C
authors.lastname: Hoon Paik
authors.forename: Kandaswamy
authors.initials: K
authors.lastname: Kalaivani
authors.forename: Jae
authors.initials: J
authors.lastname: Duk Kim
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism*; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002800:Cholinesterase Inhibitors / Q000633:toxicity*; D004847:Epithelial Cells / Q000187:drug effects / Q000473:pathology; D005260:Female; D005298:Fertility / Q000187:drug effects; D006430:Hemiptera / Q000187:drug effects* / Q000502:physiology; D007306:Insecticides / Q000633:toxicity*; D007928:Lethal Dose 50; D036701:Limonins / Q000633:toxicity*; D006080:Ovarian Follicle / Q000187:drug effects* / Q000473:pathology
chemical_list: D002800:Cholinesterase Inhibitors; D007306:Insecticides; D036701:Limonins; D000110:Acetylcholinesterase; C010329:azadirachtin