Insecticidal Effect of Fruit Extracts from Xylopia aethiopica and Dennettia tripetala (Annonaceae) against Sitophilus oryzae (Coleoptera: Curculionidae)

Abstract

The insecticidal and repellent activities of fruit extracts of Xylopia aethiopica (Dunal) A. Rich. and Dennettia tripetala (Baker f.) G.E. Schatz belonging to the family Annonaceae was studied against Sitophilus oryzae (L.), an economic, primary post-harvest pest of rice, and other cereal products. Infested rice grains (100 g) treated with 1, 2, 3, 4, and 5% (w/w) powders of both plants were evaluated for toxicity against S. oryzae every 24 h for 3 d, and during F1 progeny emergence. The essential oils of both plants were also applied at 0.5, 1, 1.5 and 2 mg cm -2 filter paper in Petri dishes for toxicity bioassays at 24 h exposure. Repellence bioassay with 10 μL solution of essential oils on filter paper was performed in a Y-Tube airflow olfactometer. Results indicate that powders of both plants significantly (P < 0.001) caused adult weevil mortality and a reduction in F1 progeny emergence than the control. Essential oils were also significantly (P < 0.001) adulticidal to S. oryzae after 24 h with the highest dose (2 mg cm -2 ) producing 100% mortality respectively. Similarly, both male and female weevils significantly avoided the test arm compared to the control arm in the Y-Tube olfactometer repellence tests. These results suggest that X. aethiopica and D. tripetala natural extracts have potential for use as part of integrated pest management of stored product protection against S. oryzae.

Natural Insecticides from the Annonaceae: A Unique Example for Developing Biopesticides

“…Similarly, both male and female weevils significantly avoided the test arm compared to the control arm in a Y-tube olfactometer repellence test. These results suggest that X. aethiopica and D. tripetala natural extracts have potential use as part of an integrated pest management system for stored product protection against S. oryzae (Ukeh et al 2012).…”

Essential oil composition and bioactivity of <i>Thuja orientalis</i> and <i>Eucalyptus camaldulensis</i>

“…Mortality record was taken at six and twenty-four hours interval after introducing insects on the seeds. Insects which did not respond to the gentle touch of a small probe were considered death (Su, 1976) Filter paper test Bioassay on the toxicity of T. orientalis and E. camaldulensis essential oils against adult C. maculates was similar to the method described in Ukeh et al, 2012) in Pyrex glass Petri dishes (10 cm diameter). Different doses of each essential oil (0.01, 0.02, 0.03, and 0.04mL) were dissolved in 0.5 mL acetone and delivered to the Petri dishes pre-lined with Whatman Number one filter paper.…”

Potential Insecticidal Activity of some Medicinal Plants Essential Oils against Red Flour Beetle ,Tribolium castaneum (Herbst) (Coleoptera:Tenebrionidae).

“…The insects attack and deteriorate the quality and the quantity of stored commodity (Ukeh, et al 2012 andNadeem, et al 2012) resulting in significant decrease in volume, nutritional value, substantial weight loss and reasonable germination damage (Nadeem, et al 2012 andPhillips andThrone 2010 ). As indicated by the FAO about 10 to 25% of the world's harvested food is devastated every year by insects and rodent pests (Ukeh, et al 2012) Red flour insect, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) is secondary pest and a standout amongst dangerous stored products pests, feeding on different grain products (Mishra, et al 2012 andIslam andTalukdar 2005). The application of various synthetic insecticides and fumigants to stored grain products over the years led to number of problems, including the development of insecticide resistance in stored grain insect pest ( Lorini andGalley, 1999 andSousa et al, 2009).…”