Evaluation of Antibacterial Effects of Some Plant Extracts Against Agrobacterium vitis

Crown gall caused by Agrobacterium vitis, is one of the most important bacterial diseases of grapevines worldwide. Promising plant extracts for the management of plant diseases are environmentally safe, long-lasting and extracts of certain plants contain alkaloids, phenolic compounds and phytoalexins. The aim of this study was to evaluate the effectiveness of five plants extract selected with preliminary tests on grapevines cv. Ekşi Kara (Vitis vinifera L.) and rootstock 41 B (V. vinifera x V. berlandieri) against Agrobacterium vitis, the causal agent of crown gal of grapevines, in glasshouse conditions. The disc diffusion method with a minor modification was used for testing of inhibitory activity. The minimum inhibitory concentration (MIC) values were determined by using modified disc diffusion method at five different concentrations and streptomycin sulphate was used as control chemical. A virulent strain of A. vitis (KbBU 23) was inoculated by inserting a hypodermic needle into young shoots of plants. Some vegetative development parameters (shoot length, shoot diameter, fresh and dry matter weight) were determined 60 days later after extract applications and the disease symptoms were evaluated by forming gal. As a result of all experiments, applications of some plant extracts suppressed the bacterial disease of grapevine and helped to compensate the disease injury. This study indicated that some plant extracts may be useful in prevention of grapevines against Agrobacterium vitis.

 This study was supported by Selcuk University Scientific Researches Coordinators