Health & Environmental Research Online (HERO)


Print Feedback Export to File
1143725 
Journal Article 
Fractions of Trichilia pallens with insecticidal activity against Tuta absoluta 
da Cunha, US; Vendramim, JD; Rocha, WC; Vieira, PC 
2006 
Pesquisa Agropecuaria Brasileira
ISSN: 0100-204X 
41 
11 
1579-1585 
This work aimed at identifying fractions of aqueous and organic extracts of the meliaceous Trichilia pallens with insecticidal activity against the tomato leafminer Tuta absoluta (Meyrick). Leaf and twig freeze-dried aqueous extracts (FDA) of T pallens were resuspended in water at a concentration of 3% and sprayed over tomato leaflets, which were infested with newly-hatched larvae. Larval mortality at 5 and 10 days after infestation (dai) were higher for leaf extracts. In a second set of experiments, 1% leaf extracts were produced by maceration in hexane (HEX), dichloromethane (DIC) and methanol (MET), and tested as described before, using acetone and water as controls. DIC extracts were the most promising as a source of substances with insecticidal activity against T absoluta larvae, and were further processed and subjected to partition assays, producing fractions in HEX, MET, ethyl acetate (ETA), n-butanol (NBU) and water (WA). After testing, 0.1% WA fraction, obtained from the partition assay of DIC extracts showed the highest insecticidal activity against T. absolula. 
Lycorpesicon esculentum; botanical insecticide; control; natural product; tomato leafminer