with a plankton net (mesh size 20 mm). A unialgal clonal culture was obtained via
single cell isolation using Pasteur pipettes. Single cells were washed twice with
physiological solution (0.9 percent NaCl, pH 7), and poured into glass tubes
(100 mL) containing Soil Water Medium (SWM, Pringsheim, 1946), which was
stabilized with CaCO3. A stable culture developed after 2 months; culture growth
was verified with an optical microscope. Stock cultures were maintained in SWM at
2471 1C on a 12 h/12 h dark/light cycle with 25–35 mE/m2
/s illumination provided
by 40-W, cool white, fluorescent tubes.