The effect of ecological factors on spore germination and the viability ofthe mycelial fragments of microscopic fungi

Spore germination and the viability of the mycelial fragments of the micros copic fungi Alternaria alternata, Penicillium spinulosum, and Mucor hiemali s were studied with respect to the action of certain ecological factors: su crose concentration (0, 0.2, 2, 10, and 100 g/l), temperature (4, 20, 25, a nd 30 degreesC), pH (3.5, 4.0, 5.0, 6.2, and 7.0), and cadmium concentratio n (0, 2, 10, and 100 mg/l). The spore germination and the viabilities of di fferent mycelial fragments were found to reach their maxima at different va lues of the ecological factors studied. This finding suggests that the vege tative and asexual types of reproduction of microscopic fungi may have diff erent ecological optima.