Myrothecium roridum on Gardenia
- 1 January 1957
- Vol. 49 (1) , 124-127
- https://doi.org/10.2307/3755738
Abstract
Myrothecium roridum was found causing a leaf spot on gardenias in several greenhouses in southeastern Pennsylvania. The leaf spots are circular, enlarging progressively up to 2 cm diameter, although many are smaller. Newly invaded tissue has a water-soaked appearance, later becoming brown. The center may be lighter than the darker advancing edges. Sporodochia are small, dark green or black masses, circular, discoid or irregular, 1 to 2 mm diameter, surrounded by white setal margins, which form on either the upper or lower leaf surface. The fungus grows well in pure culture on various artificial media including Czapek-Dox, malt extract agar and others. It is relatively tolerant of pH variations, spores germinating and hyphae growing well from 4.8 to 10.6, with no germination and no growth at 2.7. The relation of temperature to growth and spore germination was studied, and the fungus grew well at temperatures above 12[degree]C. The optimum was 25[degree]C. Artificial inoculations failed unless the leaves were previously wounded.This publication has 0 references indexed in Scilit: