The isolation of leaf protoplasts from the submerged aquatic angiosperm Potamogeton lucens L.

Abstract. A method for isolating protoplasts from leaves of the submerged aquatic angiosperm Potamogeton lucens L. is described. The protoplasts are produced enzymatically from leaf strips using 1.5% (w/v) Cellulysin, 0.3% (w/v) Macerozyme R10, and 2.5% (v/v) β-glucuronidase at 27°C in the dark. Subsequently the protoplasts are purified on a discontinuous Ficoll gradient. The yield obtained is approximately 20% of the starting material on a chlorophyll basis. The viability is high, namely more than 90% as estimated with Evans Blue. Cells of the intact leaves of P. lucens can use HCO₃⁻ for photosynthesis. ¹⁴CO₂ fixation experiments at pH 6.0 and 8.5 suggest that these isolated protoplasts can also use bicarbonate as a carbon source.