Classification of strains of Pseudomonas mori on the basis of phage sensitivity

Abstract

In order to determine the strains of P. mori and their phages distributed in Japan, many isolates of both bacteria and phages were tested for their affinity between each other.
Phage sensitivity of P. mori was studied by the drop method using 125 isolates of bacteria and 49 isolates of phage. As the result, P. mori isolates were classified into five lysotypes, A, B, C, D and E, according to their sensitivity to six phage strains as follows:
Lysotype A: Sensitive to phage groups, I, II, III, IV, V and VI.
Lysotype B: Sensitive to phage groups I, II, III, IV and V.
Lysotype C: Sensitive to phage groups III and IV.
Lysotype D: Sensitive to phage groups II, IV and V.
Lysotype E: Resistant to all phage groups.
Lysotype B was most widely distributed in Japan constituting 25.6% of the total isolates. Other lysotypes, A, C, D, E were less frequently isolated than B. And 19.2% of the total isolates could not be classified by the phage sensitivity.
These lysotypes showed similar distribution in the various districts surveyed.
The host range of P. mori phage was studied using 17 species of Pseudomonas, 9 of Xanthomonas, 3 of Erwinia, 3 of Bacillus, and 1 of both Corynebacterium and Escherichia. The host range of the phage was very narrow and it attacked only three species, such as P. phaseolicola, P. striafaciens and P. eriobotriae.