Assessment of the allelopathic potential of Ageratum conyzoides

The allelopathic potential of Ageratum conyzoides, which is one of the most dominant weeds in upland-crop areas of Southeast Asia, was investigated un der laboratory conditions. The residue obtained from an aqueous acetone ext ract of the plant shoots inhibited the germination and the growth of roots and shoots of Amaranthus caudatus, Digitaria sanguinalis and Lactuca sativa . The concentration-dependent responses of the test plants suggest that the residue of Ageratum conyzoides might contain allelochemical(s).