Biological effects of neem (Azadirachta indica) seed oil on an egg parasitoid, Trichogramma chilonis

Citation
S. Raguraman et Rp. Singh, Biological effects of neem (Azadirachta indica) seed oil on an egg parasitoid, Trichogramma chilonis, J ECON ENT, 92(6), 1999, pp. 1274-1280
Citations number
41
Categorie Soggetti
Entomology/Pest Control
Journal title
JOURNAL OF ECONOMIC ENTOMOLOGY
ISSN journal
00220493 → ACNP
Volume
92
Issue
6
Year of publication
1999
Pages
1274 - 1280
Database
ISI
SICI code
0022-0493(199912)92:6<1274:BEON(I>2.0.ZU;2-6
Abstract
Neem seed oil was tested at concentrations of 5.0, 2.5, 1.2, 0.6, and 0.3% for oviposition deterrence, feeding deterrence, toxicity, sterility and ins ect growth regulator effects against Trichogramma chilonis Ishii. Neem seed oil at 0.3% deterred oviposition (parasitization) by the parasitoid, but t he sensitivity varied considerably both under choice and no-choice conditio ns. Neem seed oil also deterred feeding at or above 1.2% concentration both in choice and no-choice tests. In feeding toxicity tests, neem seed oil at 5% concentration caused <50% mortality to both males and females but in co ntact toxicity tests, females were affected sparing males. No sterility eff ect was observed when the parasitoid was fed with neem seed oil-treated hon ey. Both pre- and posttreatment of host eggs revealed no adverse effects on the development of the parasitoid. In view of the sensitivity of the paras itoid adults to oviposition deterrent and (mild) toxic effects of neem seed oil, it is suggested that for inundative release of the parasitoid T. chil onis pretreatment of the crop with neem extracts should be avoided.