Effects of salinity, ammonium and Cytokinin in growth of Gracilaria corticata in laboratory condition

Effects of salinity, ammonium and cytokinin were evaluated on  Gracilaria corticata algae in a period of 42 days under vitro condition . G .corticata was sampled from coasts of Bandar Bostaneh in Hormozgan Province in June 2009.The algae were raised in aquariums, 40*30*60 cm with 20 liter capacity, and using suspension method in 3 replicates. Light intensity to grow was 3300 lux and temperature was 35 degree centigrade. The treatments include 25ppt (salinity of brakishwater), 35ppt (marine), ammonium (0.001& 0.002 mol.) and cytokinin (0.01, 0.001& 0.0001mol.). Sampels were harvested once a week. Length, weight and relative growth rate were measured. Result showed that, effects of environmental factors of salinity , ammonium and cytokinin on G.corticata were significant(P<0.05).The growth of G.corticata in different levels of concentration of cytokinin and salinity and ammonium in different days showed significant differences and its maximum level was observed in ammonium concentration of 0.002 mol. with 8.02 percent.