Allelopathic potential of Cyperus rotundus L. II. Isolation and identification of phytotoxins

In earlier work we had found that Purple nutsedge (Cyperus rotundus L.) has a strong allelopathic interference with several test crops. In this study Chromatographic analyses using HPLC have revealed the presence of ferulic, caffeic, hydroxyl benzoic, syringic, chlorogenic, p-coumaric acids and 3 unidentified compounds in C rotundus shoot and the same phenolic acids and one unidentified compound in the tuber. Additional chromatographic analyses showed that the shoot and tuber of C rotundus also contained 13 and 11 volatile compounds, respectively. Of these 10 identified compounds were : alpha-pinene, beta-pinene, limonene, camsaicin, artimisin, camphene, camphor, citronellal, farnesol and petalostemumol. These isolated compounds have been reported to be phytoxic against several plant species.