Effects of Physical and Chemical Factors on the Germination of Oospores ofPhytophthora capsiciin vitro

Oospores were produced by crossing two isolates of opposite mating type of Phytophthora capsici obtained from pepper on clarified V8 agar. Cultures were incubated in the dark at 24 C for 2 mo. Germination of oospores produced in the dark at 24 C was reduced by 78 or 90% when cultures were exposed to light (cool-white fluorescent, 40 μmol m -2 s -1 ) or incubated at 30 C for 1 wk before oospore collection and germination. Exposure of oospores to light during germination did not significantly affect the percentage of oospores that germinated, regardless of pregermination conditions (...)