Teliospore germination and basidiospore formation in Gymnosporangium juniperi-virginianae: a regression model of temperature and time effects

The influence of temperature on teliospore germination and basidiospore formation in Gymnosporangium juniperi-virginianae was studied in vitro. Teliospores germinated from 8 to 30 °C. Germination was first observed after 2 h from 12–28 °C but longer periods were required at lower temperatures. Promycelia formed basidiospores by 4 h from 12 to 24 °C but not until 7 h at 8 °C. Abortive germination of teliospores, without production of basidiospores, occurred from 26 to 30 °C. No germination was observed from 2 to 6 °C. Multiple regression analyses were performed and an equation relating germination of teliospores to temperature and time was formulated.