Spore liberation in Gracilaria corticata J. Agardh growing at Mandapam

Seasonal and diurnal changes in the spore liberation of Gracilaria corticata J. Agardh and the effect of exposure to air and light and dark periods on spore output have been studied. Tetraspore and carpospore shedding was found in all months of the year with a maximum output in March–April and again between September and December. Spore output varied at different times of the day and the highest values were recorded at night. Exposure to air and photoperiod affected spore production and the maximum liberation was observed in submerged fronds kept in complete darkness. Viability of tetraspores was low under laboratory conditions and only 26% of germlings were found in a healthy condition at the end of one month.