Screening of Siam Weed (Chromolaena Odorata) and African Custard Apple (Annona Senegalensis) for Nematicidal Activity

Abstract

Siam weed (Chromolaena odorata) and closely related species of Annona senegalensis had been investigated for nematicidal activity for the control of nematodes. This study was carried out to provide some information on the phytochemical constituents in these plants for nematode management.

Chromolaena odorata leaves and roots, Annona senegalensis leaves and bark collected, air-dried and ground into powder, were taken to The Central Laboratory, University of Ibadan for Infrared (IR) analysis. Phytochemical analysis was carried out in the Department of Pharmacognosy, University of Ibadan.

The IR revealed that functional groups were alcohols, alkenes, carbonyl, carboxylic acids and phenols. The phytochemicals were tannins (46.2 ± 17.9 mgg-1), saponins (81.5 ± 76.8 mgg-1), alkaloids (12.6 ± 0.7 mgg-1), flavonoids (5.3 ± 2.6 mgg-1), phenols (43.7 ± 1.6 mgg-1), cardenolides and anthraquinones.

Saponins were of the highest concentrations, followed by tannins, phenols.The phytochemicals identified have been reported to be nematicidal in activity.

Keywords: constituents, dry powders, functional groups, nematode management, phytochemicals.