Nutritional requirements for the growth of Phaeocystis globosa Scherffel
球形棕囊藻生长的营养需求研究

Effects of N,P,Fe,microelements and vitamins on the growth of two strains(Hong Kong strain and Shantou strain) of Phaeocystis globasa Scherffel were investigated in the present study.N,P,Fe,microelements and vitamins were supplemented to the media at various combinations and concentrations according to orthogonal designed scheme.Results indicated that microelement P was a crucial element for the growth of both HK and ST strains.P.globosa cells grow faster in the medium with supplementary P.In the medium without P,growth curve can't be observed.The range of specific growth rate for ST strain was much higher than that of HK strain,which indicated that ST strain was more sensitive than HK strain to nutrients.Statistical analysis indicated that specific growth rate of P.globosa were significant at the level of p<0.01 and p<0.05 when growing at different P and N concentrations respectively.Fe,microelements and vitamins had no remarkable effects on the growth of both strains,which suggested that the natural sea water has plenty of Fe,microelements and vitamins for the growth of P.globosa.The order of nutritional impacting factors was as follow: P>N>microelements>Fe>vitamin.Our results imply that eutrophication of coastal water is one of the critical factors for triggering P.globosa bloom in the South China Sea.