Regulation of growth and biomolecule of Aphanothece sp. by phenoxy herbicide 2, 4-d

Download this article as: 

Toxicity of the herbicide 2, 4-Dichlorophenoxy acetic acid to unicellular cyanobacterium Aphanothece Sp. has been studied. Stimulation in cyanobacterial growth was observed at 100 ug ml-1 while higher concentrations had inhibitory effect with 1600 μg ml-1 being completely lethal. The sublethal concentration (1200 μg ml-1) allowed few cell (frequency approx 10-7) of cyanobacterium population into filamentous aseptate structure and regained the normal course of the unicellular pattern of differentiation in absence of the herbicide. 2, 4-D resulted in decline of chlorophyll a and no effect on DNA content even at the growth stimulatory concentration (100 μg ml-1). However, cell protein, RNA and phycobillin contents were increased up to 400 μg ml-1 , while higher concentrations have inhibitory effects. Cellular abnormalities by higher concentration and possible mode of action of 2, 4-D at the level of cell division are discussed.

Growth Biomolecules; Aphanothece sp. Phenoxy herbicide, 2, 4-D