Effect of salinity and light intensity on growth of carpospores of Hypnea valentiae (Turn.) Mont. (Gigartinales, Rhodophyta) under laboratory conditions

摘要

Carposporesof Hypneavalentiae were cultured under five different salinities (25, 30, 35, 40 and 45ppt) with three different light intensities (9, 18 and 28μ Em~(-2) s~(-1)) in the laboratory condition (20 ± 2°C with 12:12 light and dark periods). Higher Extension Growth Rate (EGR) and Specific Growth Rate (SGR) were observed in lower salinity level (25ppt) at high light intensity (28μ Em~(-2) s~(-1)) and in higher salinity level (45ppt) at low light intensity (9μ Em~(-2) s~(-1)). Therefore it is obvious that Hypnea valentiae grows in saliniw ranges between 25 - 45 ppt which conforms the earlier observation that H. valentiae can tolerate wide range of salinities between 15-55 ppt.