title: Effects of neem-based and chemical insecticides on some arthropods in alfalfa.
abstract: In this study, we tested the effects of two different doses of neem (azadirachtin) on the alfalfa weevil, Hypera variabilis Hbst. (Coleoptera: Curculionidae), aphids and predators (Coccinellids, anthocorids, chrysopids and spiders) and compared the effects with those of a broad spectrum insecticide (malathion) in a controlled experiment in 1998 and 1999. Malathion treatments reduced alfalfa weevil densities significantly (p < 0.01) by 77.9 and 87.4% in 1998 and 1999, respectively. Alfalfa weevil numbers in the low dose neem-treated plots were lower by 45.2% in 1998 and 50.2% in 1999. There were 45.3% fewer alfalfa weevils in the high dose neem-treated plots in 1999. In 1998, aphid numbers were reduced by 11.1, 25.3 and 41% in the low dose neem-treated plots, the malathion-treated plots and the high dose neem-treated plots, respectively. Aphids were more abundant in the malathion-treated plots, whereas they were fewer in the neem-treated plots compared to the control in 1999. The treatments did not have any significant effects on the total numbers of predators.
authors.affiliation: Yuzuncu Yil Universitesi, Ziraat Fakultesi, Bitki Koruma Bolumu, 65080, Van, Turkey.
authors.forename: E N
authors.initials: EN
authors.lastname: Yardim
authors.forename: I
authors.initials: I
authors.lastname: Ozgen
authors.forename: H
authors.initials: H
authors.lastname: Kulaz
mesh_terms: D000818:Animals; D001042:Aphids / Q000254:growth & development*; D001517:Coleoptera / Q000254:growth & development*; D007300:Insect Control; D007306:Insecticides / Q000494:pharmacology*; D036701:Limonins / Q000494:pharmacology; D008294:Malathion / Q000494:pharmacology; D000455:Medicago sativa / Q000469:parasitology*; D011156:Population Density
chemical_list: D007306:Insecticides; D036701:Limonins; C010329:azadirachtin; D008294:Malathion