An investigation of allelopathic effects of Artemisia herba-alba Asso, aqueous extract on common bean (Phaseolus vulgaris L.)

Abstract

The objective of this study was to investigate the impact of allelopathic potentials of aqueous extract of Artemisia herba-alba aerial parts on germination and secondary metabolites accumulation in common bean seedlings. Quantitative analysis of aqueous extract of Artemisia showed the phenolic compounds and flavonoids that might be concerned as allelo-chemicals agents. After 8 days, the germinated common bean seedlings were significantly inhibited with the increase in concentration of Artemisia extract. However, the phenolic compounds in common bean seedlings increases when the concentration of Artemisia extract increased. Degradation of storage carbohydrates of common bean seedlings was significantly increased with increasing the concentration of Artemisia extract. It seems that the enhance-ment of total carbohydrates was attributed to the inhibition of amylase activity that reduced the contents of reducing and non-reducing sugars. However, the polysaccharides remained at high level when compared with those of the control. Inhibition of protease activity led to accumulation of free amino acids and protein contents in germinated seedlings of common bean. Although, 4% aqueous extract of Artemisia shoots contains allelopathic chemicals and phytotoxic, this effect led to an increase in unsaturated and saturated fatty acids in germinated common bean seedlings.