Influence of ultraviolet irradiation on nutrient-gleaning capacity of two unicellular algae.

Two unicellular algae, viz., Anacystis nidulans and Chlorella vulgaris, growing in polluted effluents, were isolated in unialgal and bacteria free culture. They were mutagenically exposed to ultraviolet radiation and variant strains endowed with differing capacities for growth and nutrient-gleaning were successfully isolated as distinct clones on agar plates. One such clone each of the two species was tested further and found stable. While these variant strains grew more slowly than untreated controls, statistically significant differences with respect to phosphate and nitrate uptake were found between treated and control strains of the two species.