Allelopathic Activity of Some Medicinal Plants against Erwinia carotovora

Many medicinal plants, exhibit allelopathy to biological management of plant pathogens by reducing their regeneration. This process involving secondary metabolites produced by plant influence the growth and development of agricultural and biological system. This research was to determine the allelopathic potential of aqueous extracts of different medicinal species (Artemisia herba alba, Pistacia atlantica and Juniperus phoenicea) against plant pathogenic bacteria (Erwinia carotovora subsp. Carotovora) in comparison to the antibiotic Streptomycin (positive control). Effect of water extracts evaluated for different concentrations of different extracts for each plant studied was examined under laboratory conditions in petri dishes. The results showed that all the extracts significantly inhibited growth of tested bacteria. The differences in their inhibition depend on to the type of plant and concentration of extract. However, Artemisia herba alba extracts had greater inhibitory potential. Based on the study results, aqueous extracts of three plant species (A. herba alba, P. atlantica and J. phoenicea) showed a negative allelopathic effects on plant pathogenic bacteria (Erwinia carotovora subsp. Carotovora).