Uptake of potassium by algae and potential use as biofertilizer

Green algae, Coelastrella oocystiformis and Chlorolobion braunii were subjected to varying concentrations of potassium (200, 400, 600, 800, 1000 and 2000 ppm). These two algal forms were selected so as to also check if shape of algal forms plays a role in their ability to absorb potassium. The cultures were kept at 5000 lux for a period of 30 days to check their stability for potassium absorption capacity. The algal biomass was harvested, dried and converted to ash for estimation of potassium using method described by Jacobs and Hoffman (J Biol Chem 93: 685–691, 1931 ). C. oocystiformis has highest ash content of 30.5 % when exposed to 400 ppm of K + and at this concentration it could take up to 74.8 % of total potassium it was exposed to C. braunii has ash content of 37.5 % when exposed to 1000 ppm of K + , but has potassium content of 12.35 % when exposed to 1800 ppm of K + . Chlorolobion braunii , however, has greater potassium uptake of 40.66 % when exposed to 400 ppm of K + .