The Effect of Temperature on Germination of Chlamydospores of Phytophthora ramorum.

Author , ,
Date 2014
Publication Mycologia, 106(3): 424–430.
Key Words
DOI10.3852/13-313
AbstractMycelium-free chlamydospores of 12 isolates of P. ramorum representing three clonal lineages were produced with a method involving incubation in nonsterile sand at 20 C in darkness for 30 d. Chlamydospores were incubated on selective agar medium at 5, 10, 15, 20, 25 and 30o C and germination assessed after 1, 2, 4, 6 and 8 d incubation. The optimal temperature for germination based on 8 d incubation was 20o C for all three clonal lineages tested (NA1, NA2, EU1). Mean germination rates were 2, 21, 44, 67, 32 and 0 percent at 5, 10, 15, 20, 25 and 30o C respectively for all isolates combined. The highest mean germination rate was scored by isolates of the EU1 clonal lineage at 20o C (85%) after 8 d incubation However, substantial variation was observed among isolates within each clonal lineage. Overall temperatures and days of incubation on which germination was assessed isolates of the NA1 clonal lineage had the lowest mean germination, even though one isolate had the highest germination of any isolate in any lineage. The results indicate that 20o C is the optimal germination temperature for P. ramorum chlamydospores and that a great disparity in germination percentage can exist within isolates, even within a single clonal lineage.
Full Citation Tooley, P.W.; Browning, M.; and Leighty, R.M. 2014. The Effect of Temperature on Germination of Chlamydospores of Phytophthora ramorum. Mycologia, 106(3): 424–430. DOI: 10.3852/13-313.