Antibacterial effect of Pimenta racemosa extracts on Ralstonia solanacearum and bacterial wilt of tomato in Martinique. Davezies I. 2014. Mémoire de stage, cursus ingénieur ISARA –Lyon. 89p.

Bacterial wilt caused by Ralstonia solanacearum (phylotype IIB/4NPB) is a major disease in vegetable crops, whose control has been problematic for decades. To control bacterial wilt, the antimicrobial effect of three chemotypes of Pimenta racemosa extracts was tested at 3 concentrations (0.04%, 0.07% and 0.14% vol/vol) in in vitro and in vivo tests. The extracts with the clove smell chemotype showed efficient antibacterial properties in the in vitro tests. In greenhouse extracts of clove smell chemotype of P. racemosa reduced the incidence of tomato bacterial wilt. With P. racemosa extracts at 0.14%, our results showed that 2.4% to 0% of tomato plants were affected by the disease whereas in the untreated control 64% of tomato plants were affected by the disease. In conclusion, our study demonstrated that Pimenta racemosa extracts and especially the clove smell chemotype can be used for biocontrol of bacterial wilt disease on tomato