Identification of grape crown gall disease caused by Agrobacterium vitis and research on possible control of the disease

In this study vineyards in Mersin, Adana, Osmaniye, Hatay, Gaziantep,Adıyaman and Kahramanmaraş provinces were surveyed and infected plant samplesby crown gall agent were collected. Infected plants were recorded in vineyards ofMersin, Gaziantep, Hatay, Adıyaman and Kahramanmaraş provinces. Forty-seventumorigenic bacterial isolates were isolated from galls of infected plants. All isolateswere identified as Agrobacterium vitis by classical bacteriological techniques, PCR,fatty acid analysis and pathogenicity tests on grape, tomato and kalanchoe plants. Allisolates caused crown gall on grape shoots. No gall formation observed on tomato(Lycopersicum esculentum Mill. cv. Heinz 2274) and kalanchoe (Bryophyllumdaigremontianum (Raym.-Hamet & E.P. Perrier) Berger) plants by seven and eightisolates, respectively.Totally 464 Plant Growth Promoting Rhizobacteria (PGPR) were isolatedfrom 39 soil samples collected from vineyards of Mersin, Adana, Osmaniye, Hatay,Gaziantep and Kahramanmaraş. Sixty-three candidates PGPR isolates solubilizedphosphorus on solid NBRIP medium. Ten candidate PGPR isolates which havesolubilized phosphorus with the highest ratio were used in pot experiments. PGPRisolates, Ga7/3-6 (%45), Ga10/2-5 (%97), Os1/3-1 (%80), OsD1/3-1 (%98) veHaD6/3-1 (%75), significantly reduced galls weight on grape plants in potexperiments. When lipopolysaccharide (LPS) extracted from A. vitis applied tocutting grapevine, gal size was reduced by 91.5% rate.Key words: Grape, LPS, crown gall, Agrobacterium vitis, PGPRII