Toxic and oviposition deterrent effects of some plant extracts and their combination with deltamethrine against adults of Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae)

Abstract

This study was conducted to determine the contact and oviposition deterrent effects of nettle ( Urtica dioica ), basil ( Ocimum basilicum ), hops ( Humulus lupulus ), spurge ( Euphorbia cyparissias ) methanol extracts against Callosobruchus maculatus (F.) (Col: Chrysomelidae) adult. In addition, contact toxicity of mixtures of plant extracts with deltamethrine was determined. The experiments were conducted in laboratory conditions at 28±0.5˚C, 55±5% RH and continuous darkness. In the tests of contact effect, the concentrations of 0.156, 0.312, 0.625, 1.25, 2.5, 5, 10, 20% (w/w) of the plant extracts were applied to Callosobruchus maculatus adult . Contact effect to adult was determined by topical application method. In contact effect studies, the increasing concentrations of the extracts were caused to increase of mortality rates after 24, 48 and 72 hours. The highest mortality rate was found in the U. dioica extract whereas the lowest was in the extracts of H. luputus in all phases. Oviposition deterrent effects of the plant extracts were determined with spraying of 1 ml extract (concentrations of 2.5, 5, 10% (w/w) of plant extracts) onto chickpea from spray tower. Oviposition deterrent rate was as nettle>hops>basil>euphorbia in order of all the concentrations of the same plant. Plant extracts mixed with deltamethrine did not cause an increase in the toxic effect of deltamethrine.