1986 Volume 52 Issue 3 Pages 413-421
Occurrence of hairy root has been detected on roses in Shizuoka prefecture since 1979. The causal bacterium was isolated from the rootlets of Floribunda rose, Hybrid tea rose and Climbing rose, and was tested for its pathological and bacteriological characteristics. Eighteen isolates were identified as Agrobacterium rhizogenes based on their pathological traits as well as 82 cultural, physiological and biochemical properties. These isolates were differentiated into two biovars due to the differences in the following characteristics: 3-ketolactose production, Kovac's oxidase, H2S production, arginine dihydrolase, ferric ammonium citrate test, nitrate reduction, nitrate respiration, acid production from raffinose. ethanol and erythritol, utilization of L-tyrosine, malonate and tartrate, litmus milk reaction, growth factor requirement, growth at 35 C, growth in 2% NaCl pepton water, growth on Schroth et al. medium, New and Kerr medium, calcium glycerophosphate agar, sodium selenite agar, Starr's basal medium, congo red mannitol agar and aniline blue mannitol agar, and growth in a synthetic medium with asparagine and ammonium salts as a sole source of C and N. Seven isolates were classified as biovar 1, and other 11 isolates as biovar 2. The virulence of these isolates to rose and tomato were stronger than that to carrot. The GC contents determined by HPLC method were in the range of 58.7-60.7%.