Isolation and identification of phenolic fractions from mixture of sorghum, sunflower and mulberry extract and its allelopathic effect on little seed canary grass and wheat

摘要

Little seed canary grass is a pernicious weed of major winter crops including wheat. Plant compounds are desirable over synthetic herbicides because of economic and environmental benefits. Combined sorghum, sunflower and mulberry extract was prepared using methanolic extraction. Twenty two phenolic fractions were separated through preparative thin layer chromatography (thickness 0.75 mm) using CH2Cl2-n-hexane-MeOH (6:4:1 v/v/v ratio) solvent system, from combined sorghum, sunflower and mulberry (SSM) methanolic extract. Bioassay study was conducted to evaluate their allelopathic effects on seedling germination and early seedling growth of little seed canary grass (Phalaris minor Retz.) and wheat (Triticum aestivum L.). Treatments T3 tentatively identified as 3, 4-dihydroxy cinnamic acid and caffeic acid and T19 which was still a mixture of compounds, one of them was tentatively identified as 4-hydroxy benzaldehyde, retarded the germination of little seed canary grass, with little inhibitory effects on wheat.