Potential Allelopathic Effect of Species of the Asteraceae Family and Its Use in Agriculture

Some species are capable of producing substances that affect seed germination, stimulating, or retarding this process, and can also suppress the development of other plants, acting as an antagonistic plant. This can occur naturally, through the release of exudates, or through the action of essential oil, extracts obtained from different parts of the plant, or plant residues with potential allelopathic action. The aim of this chapter is to present the main plant genera of the Asteraceae family with potential phytotoxic or allelopathic activity, with a suppressive effect on the growth of herbicide-tolerant weeds. The genus defined were Acmella, Artemisia, and Bidens, highlighting the form of use—plant extract, essential oil, or plant residues. The Asteraceae family is considered a repository of species to be explored for allelopathy with several associated secondary metabolites such as terpenes, saponins, alkaloids, alkamides, cinnamic acid derivatives, and flavonoids. In addition to these, for the genus Bidens, the presence of the acetylenic compound phenylheptatriine (PHT) is considered an important allelochemical with potent allelopathic action. The presence of this compound is associated with the cytotoxic activity of representatives of this genus, which can be a source of prospecting for new molecules to be used as bioherbicides