Effects of chemicals on Fischerella muscicola (Thuret) Gom.

Abstract

Fischerella muscicola (Thuret) Gom. was isolated in axenic culture, from the roof of a building. Effects of the incorporation of manganous chloride, caffeine, lanthanum acetate, maleic hydrazide, coumarin, thioglycollic acid, colchicine, and uranyl nitrate in the culture medium on the alga was investigated. The sublethal and lethal concentrations of chemicals were manganous chloride 5.0 mM and 7.5 mM; caffeine 5.0 mM and 10.0 mM; lanthanum acetate 0.7 mM and 1.5 mM; maleic hydrazide 2.0 mM and 4.0 mM; coumarin 1.4 mM; thioglycollic acid 1.0 mM; colchicine 10.0 mM; and uranyl nitrate 0.5 mM and 1.0 mM. The sublethal concentrations thus determined were higher than those found in bacteria.Among the effects, the killing of a few cells, lag in division of cells, cell enlargement or elongation, and formation of irregular clusters of cells were temporary in nature. On the other hand, the changes in pigment composition, vacuolization, production of gas vacuoles, increase in frequency of heterocysts, suppression of akinete formation, and formation of uniseriate prostrate branches were permanent.