Phytotoxic Potential of Onopordum acanthium L. (Asteraceae)

Abstract

Onopordum acanthium L. (Asteraceae) is a plant native to southern Europe and southwestern Asia, but it is invasive in disturbed areas and agricultural fields around the world, causing many agronomic problems by interfering with crops or preventing animals from grazing on pastures. Allelopathy could be one of the reasons that this plant has spread over different continents. The aim of the present study was to bioprospect O. acanthium leaf extracts through the isolation and purification of allelopathic secondary metabolites with phytotoxicity to explain their invasive behavior. Phytotoxic activity was tested using etiolated wheat coleoptiles. The most active extract was selected to perform a bioassay-guided isolation of two flavonoids, pectolarigenin (1) and scutellarein 4'-methyl ether (2), and two sesquiterpene lactones, elemanolide 11(13)-dehydromelitensin β-hydroxyisobutyrate (3) and acanthiolide (4). All compounds were isolated for the first time from O. acanthium, and acanthiolide (4) is described for the first time. Compound 3 strongly inhibited the growth of wheat coleoptiles and 1 showed an intermediate effect. The results indicate that these compounds could contribute to the invasion of O. acanthium in ecological systems and agricultural fields.

Screening of Tunisian plant extracts for herbicidal activity and formulation of a bioherbicide based on Cynara cardunculus

“…In addition, the C. cardunculus crude methanolic extract had the best herbicidal activity in post-emergence under greenhouse conditions. C. cardunculus leaves are known to be a good source of polyphenols (Omezzine et al, 2011;Falleh et al, 2008) The herbicidal activity of phenolic extracts in pre-emergence is widely documented (Javaid et al, 2010;Araniti et al, 2015;Watanabe et al, 2014;Nekonam et al, 2014;Bessada et al, 2015;Uddin et al, 2014;Ma et al, 2018;Schleiden et al, 2019), but to our knowledge no study had yet focused on their effect in post-emergence by direct spraying on weed leaves. C. cardunculus, which is well known for its coagulant properties (Prados & Pino, 2007) and phytotoxic effect in pre-emergence (Rial et al, 2014;Rial et al, 2016;Scavo et al, 2019), is unveiled for the first time for its herbicidal effect in post-emergence.…”

“…The greatest herbicidal activity was obtained using extracts from two Asteraceae plants (A. herbaalba and C. cardunculus), which inhibited seed germination and seedling growth of three weeds. The Asteraceae family has been found to harbour the most prominent biocidal substances for agriculture and to be a good source for isolating and purifying allelopathic secondary metabolites (Bessada et al, 2015;Watanabe et al, 2014). In addition, the C. cardunculus crude methanolic extract had the best herbicidal activity in post-emergence under greenhouse conditions.…”

Chemical profile and phytotoxic action of Onopordum acanthium essential oil

“…Further experiment revealed that β-eudesmol (10.10%), which was a dominant compound in flower oil but not detected in leaf and stem oils, was most likely responsible for the potent phytotoxic activity of flower oil by comparing the strength of β-eudesmol and flower oil. β-eudesmol was found to possess antiangiogenic, antimutagenic, anticancer, antioxidant activity and so on, however there is no report on its phytotoxicity 21 , 31 – 36 .…”

Traditional Medicine Plant, Onopordum acanthium L. (Asteraceae): Chemical Composition and Pharmacological Research

“…4’-methyl ether of scutellarein (6-hydroxy apigenin) was found in leaves in the amount of 9.5 mg per 215 g of dry leaves [26]. Other methoxy derivatives (nepetin, chrysoeriol, hispidulin, pectolinarigenin) were detected in the aerial part in the amount of 8.0 mg/4.4 kg dry raw material (nepetin), 3.5 mg/4.4 kg dry raw material (hispidulin), as well as in leaves and 1.6 mg/215 g dry weight (pectolinarigenin) and flowers (chrysoeriol) [23,24,25,26].…”