1981 Volume 47 Issue 4 Pages 443-448
A new bacterial disease was found on Myrica rubra S. et Z. growing in Okinawa, Shizuoka, Fukuoka, Mie, Tokushima prefecture, Japan. Galls with size of one to several cm in diameter and very rough surface were formed on either trunks or twigs. Small galls were also found on leaf petioles. The causal bacterium was pathogenic only on Myrica rubra, but not on the other plants belonged to 35 families and 69 species. The bacterium was a gram-negative rod with 1 to several polar flagella and 56.67 GC moles % of DNA. It was an aerobe and metabolized glucose oxidatively. Negative results were obtained with the tests such as nitrate reduction, gelatin liquefaction, H2S production, indol production, production of fluorescent pigment, arginine dihydrolase, Kovács' oxidase, starch hydrolysis, KCN inhibition and growth at 41 C. However, fluorescent pigment was produced when stiff agar was used instead of powdered agar. Positive reaction were obtained with the tests such as catalase reaction, tobacco hypersensitivity, levan formation, and hydrolysis of Tween 80. The following carbohydrates and an amino acid were utilized as a sole source of carbon: xylose, glucose, mannose, galactose, sucrose, fructose, glycerol, mannitol, arabinose, tartrate, citrate, malate, succinate, L-arginine. The carbon sources unused were as follow: lactose, maltose, trehalose, salicin, rhamnose, malonate, L-valine and β-alanine. Litmus milk turned blue and decolored later. The optimum growth temp. was 25-30 C, and the minium 4.5 C. Growth occurred at 4% NaCl but not at 5%. From these bacteriological characteristics, the authors inclined to identify the present bacterium as a new pathovar of Pseudomonas syringae and named Pseudomonas syringae pv. myricae pv. nov. Culture no. MR 1 was proposed as the pathotype strain and deposited to The American Type Culture Collection (No.33544), U.S.A., National Collection of Plant Pathogenic Bacteria (No.3143), England and Plant Disease Division Culture Collection (No.7118), New Zealand, respectively.