INA BACTERIA ISOLATED FROM DIAMONDBACK MOTH, PLUTELLA-XYLOSTELLA L PUPAE (LEPIDOPTERA, YPONOMEUTIDAE)

Three isolates of ice nucleation active (INA) bacteria were obtained from diamondback moth pupae. Relative concentration of INA bacteria in pupal bodies was low. Ice nucleation activity of 3 isolates was observed only when pre-cooled at 5-degrees-C for 1 to 7 days. This result coincides with the fact that the number of individuals with high SCP increased when pre-cooled at 5-degrees-C for 5 days. Characteristics of the 3 INA isolates were as follows: a light yellow, translucent, circular and glossy surface colony was formed with motile, oxidase activity positive, gram negative, rod shaped bacteria. The bacteria were presumed to be an Erwinia species.