The effect of the fungicides on growth of our common fungal contami-nants was also evaluated. These contaminants were identified as fungi based on their morphology, sensitivity to fungicides, and insensitivity to antibiotics that target bacteria. Also, based on morphology, there appeared to be at least two different species, although they were not assigned taxonomically. Table 1 shows that carbendazim was effective at the lowest concentration used (1 μg/mL), whereas thiophanate-methyl and benomyl effectively blocked fungal growth at 20 μg/mL (there was a similar response by both contaminants). These and the aforementioned results indicate that all three of these compounds could be used in controlling fungal contamination of C. reinhardtii cultures.