Time and temperature combinations that are lethal to Pseudomonas syringae pv. actinidiae

TitleTime and temperature combinations that are lethal to Pseudomonas syringae pv. actinidiae
Publication TypeJournal Article
Year of Publication2011
AuthorsPushparajah, I. P. S., & Everett K. R.
JournalNew Zealand Plant Protection
Volume64
Pagination291
Date Published2011
KeywordsAnnual Report 2011-12
Abstract

The thermal death point was determined in vitro for three isolates of Pseudomonas syringae pv. actinidiae (Psa). A bacterial suspension was treated by placing in an Eppendorf tube then floating in a water bath at seven temperatures, from 26.3 to 60 degree C. At each temperature an aliquot was removed after 5, 15, 35, 75, 155, 315 and 635 min, placed onto King's medium B (KMB) in Petri plates and spread with a sterilised bent glass rod. Petri plates were placed at 25 degree C for 24 h and colonies counted. There were three isolate replicates each in an Eppendorf tube per time:temperature combination. There was no difference in response between isolate replicates, but time and temperature differences were significant (P<0.0001). Any time:temperature combination greater than 45 degree C for 5 min killed Psa. Modelling the thermal response suggested that 42.5 degree C for longer than 150 min was the lowest time:temperature combination that could be used to kill the bacterial cells.