Growth of Gracilaria edulis in relation to environmental factors in field cultivation

Field cultivation of Gracilaria edulis was carried out in the nearshore areas of Gulf of Mannar and Palk Bay near Mandapam to determine the various environmental factors which affect the growth of this agar yielding seaweed. These culture experiments were conducted in Gulf of Mannar from October to April during the years 1986-89 and in Palk Bay from April to October during the years 1987-88 when the sea was calm at both places. The epiphytes, epifauna, Low light intensity and sedimentation caused by turbulence of water and grazing by fishes were found to be the primary factors hampering the growth of cultured G. edulis. There was no good growth of G. edulis in Palk Bay during the entire period of this study. But in Gulf of Mannar the growth of G. edulis was good between November and March with maximum yield during the months December to February1 March. The suitable period for field cultivation of G. edulis in Gulf of Mannar is from December to March.