Evaluation of chemical composition and inhibitory effects of Hypochaeris radicata L. extracts on seed germination and growth of Echinochloa crus-galli L.
Allelopathy is a common plant-resistance mechanism in nature, this mechanism demonstrates the growth of this plant that may affect the growth and development of other nearby plant species through the production of secondary compounds. In this study, the allelopathic ability of ethanol extracts from Hypochaeris radicata L. on Echinochloa crus-galli L. was investigated in laboratory conditions. The extracts from stems of Hypochaeris radicata L. at the concentration of 5 mg/mL showed highest inhibition (73.33%) on seed germination of barnyard-grass (Echinochloa crus-galli L.). In this study, total polyphenol and flavonoids in Hypochaeris radicata L. were determined by spectrophotometry. Polyphenol and flavonoids present in all parts of the Hypochaeris radicata L. were investigated. The highest polyphenol content in leaves was 9.67 mg/g extract and the flavonoid content in roots was 29.56 mg/g extract. Phenolic acids in extracts from leaves, flowers, and roots were identified by HPLC. The results showed the presence of 7 phenolic acids including chlorogenic, syringic, vanillic, synaptic, p-coumaric, benzoic and ellagic in the extracts. The findings highlighted that Hypochaeris radicata L. is a wild plant species with great potential for allelochemicals.