Antifeedant effect of plant extracts on the poultry pest Alphitobius diaperinus (Coleoptera: Tenebrionidae): an exploratory study

In this exploratory study, the antifeedant activity of ethanolic extracts of nine plants native from central region of Argentina on Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae) was evaluated, looking for low environmental impact management alternatives. Adults of A. diaperinus were exposed to food treated with the extracts to assess whether feeding behaviour and survival were altered. None of the extracts affected adult survival. However, the extracts of Gaillardia megapotamica, Vernonanthura nudiflora, Baccharis artemisioides, Lithraea molleoides, and Ambrosia artemisiifolia had a strong antifeedant effect (92-96%). The other extracts evaluated slightly affected (50-55%) the food consumption. The extracts of G. megapotamica and B. artemisioides were administered with the food to the fifth larval stage to assess whether they affect survival, feeding behaviour, and weight of immature forms. The B. artemisioides extract generated a marked deterrent effect of feeding on the larvae (76%) during the first week of experimentation, although the effect weakened over time. On the other hand, G. megapotamica produced a moderate deterrent effect (41-74%) throughout the experiment. The extracts also affected weight, survival, and number of larval exuviae in relation to the control

Isolation and Identification of Insect Antifeedant Compound from Ethanol Extract of Hemidesmus indicus Root

Phytochemicals with insect antifeedant potential can be used as a safer alternative to harmful chemicals that are used as grain protectants. The insect antifeedant effect of the extracts and fractions of Hemidesmus indicus root were tested against the stored grain insect pest Corcyra cephalonica Stainton. Bioactivity-guided study of ethanol extract of Hemidesmus indicus root led to isolation and identification of a triterpenoid, Lupeol with insect antifeedant potential. Although Lupeol showed insect antifeedant potential the ethanol extract was found to be more effective as an antifeedant. This implies that the synergistic action of compounds present in the ethanol extract of H. indicus root is responsible for the higher antifeedant potential.

Effects of Cantharidin and Norcantharidin on Larval Feeding and Adult Oviposition Preferences of the Diamondback Moth (Lepidoptera: Plutellidae)

The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is a destructive insect pest of cruciferous plants that has developed resistance to almost every listed commercial insecticide. Cantharidin as an animal-derived biopesticide is a natural defensive compound produced by Meloidae insects with toxicity to many insects including P. xylostella. Norcantharidin is an important substitute of cantharidin and has similar insecticidal activities to cantharidin. Although the toxicity of cantharidin and norcantharidin to P. xylostella has been reported, little research has focused on the effects of cantharidin or norcantharidin on the behavior of P. xylostella. In this study, we investigated the feeding behavior of third-instar larvae and the oviposition preference of adult P. xylostella in order to explore the effects of different concentrations of cantharidin and norcantharidin. Results show that cantharidin and norcantharidin have antifeedant effect on P. xylostella larvae. The values for AFC50 were 13.0228 and 149.4210 mg/ml, respectively. Furthermore, the oviposition deterrence rate of cantharidin on P. xylostella ranged from 49.37 to 58.24% and that of norcantharidin was from 20.88 to 33.33%. These results suggest cantharidin and norcantharidin may have repellent and antifeedant effect on P. xylostella, which could contribute toward using biopesticides to manage P. xylostella and may provide a new strategy for integrated pest management.

Antifeedant effect of water-soluble anthraquinone pigment of Kerria lacca

not availableJ. bio-sci. 25: 77-81, 2017