Screening for antibacterial activity in selected medicinal plant extracts against Xanthomonas euvesicatoria

Background and objectives: The environment and human health have fared badly from the use of ‎synthetic pesticides as a form of pest control. Plants are considered as an alternate pesticide for pest control ‎without sacrificing the environment and their potency on pests.‎ Methods: Aqueous extracts of (Lavender flower, olive leaves, thuja leaves and fruit, fig milk, clove flower buds, Arabic gum, Borage, Tarragon, Cress seed and Carob tree) were tested against newly isolated Xanthomonas euvesicatoria (Acc. No. OP115671) from symptomatic tomato plants. Results: The in vitro results showed that clove extract is highly effective in inhibiting bacterium growth followed by borage, carob and tarragon respectively. The minimum inhibitory concentration MIC and the minimum bactericidal concentration MBC of clove extract reached 3.125 and 6.25 mg/ml respectively.  Conclusions: This study indicated that aqueous extract of clove can potentially be used as a promising bactericide in the near future. Key Words: Clove, borage, carob, tarragon, MIC and MBC.