Indole-3-acetonitrile is a critical molecule with weed allopathic suppression function in broccoli (Brassica oleracea var. italica).

Abstract

Cruciferous plants are frequently used for ecologically benign weed control in agricultural production. The varieties were the most effective, Most effective Broccoli varieties were screened using the entropy method-based topsis model at first. Result showed that Lvwawa and Lvbaoshi were most effective in allelopathic suppression on radishes. Column and thin-layer chromatography were used to extract the allelopathic compounds from broccoli residues, which contained various herbicidal active substances; among them, purified single-molecule indole-3-acetonitrile has a stronger inhibitory effect than pendimethalin (commercial herbicide). The weed inhibition rate increased with increasing broccoli residue dosage, with a 40 g/m2 broccoli residue dose yielding the highest suppression rate. Its effect was similar to that of indole-3-acetic acid. Too much of this substance leads to the plant's death. Moreover, broccoli residues had effective control effect on weeds in natural soils in greenhouse and field trials. The results demonstrated that broccoli residue could be used for weed management in field for abundant allopathic suppression molecules to weeds, and that Indole-3-acetonitrile is one of the most important allopathic molecule.