东海原甲藻对不同磷源的利用特征

The utilization of Prorocentrum donghaiense to four different types of phosphorus

采用单因子实验,以NaNO3作为唯一氮源,固定初始氮浓度为40μmol.L-1,设置六个初始磷浓度梯度:0.1μmol.L-1、0.5μmol.L-1、1.0μmol.L-1、2.0μmol.L-1、5.0μmol.L-1、10.0μmol.L-1,对比研究了东海原甲藻(Prorocentrum donghaiense)对4种不同磷源的利用特征及其这4种不同磷源对东海原甲藻的营养价值。结果表明:东海原甲藻既可以直接吸收利用无机磷——磷酸二氢钠(NaH2PO4),又可以不同程度地利用3种小分子有机磷:三磷酸腺苷二钠盐(ATP)、D-葡萄糖-6-磷酸钠(G-6-P)和甘油磷酸钠(G-P);东海原甲藻在以NaH2PO4、G-6-P和ATP分别作为磷源时的最大比生长率(μmax)值相差不大,3种磷源对最大生物量的贡献也基本相近;但是以G-P作为磷源时则明显有最低的μmax值,其对最大生物量的贡献也最低。东海原甲藻对这4种磷源的利用特征说明:长江口自然海水中与三种小分子有机磷结构相似的溶解有机磷在一定程度上也可以为东海原甲藻赤潮的爆发和维持提供磷源。

Single factor test was used to study the effects of four different types ot phosphorus on growth of Prorocentrum donghaiense ,NaNO3 was the sole nitrogen source, the initial nitrogen concentration was 40μmol·L^-1, and the six original phosphorus concentrations was setup as the following： 0.1μmol·L^-1, 0.5μmol·L^-1, 1.0μmol·L^-1 2.0μmol·L^-1, 5.0μmol·L^-1, 10.0μmol·L^-1 The four different types of phosphorus were ： NaHEPO4（Sodium dihydrogen phosphate）, ATP（Adenosine disodium triphosphate）,G-6-P（D-glucose-6-phosphate,sodium salt） and G-P （Sodium glyceroophosphate）;The results showed that all four types of phosphorus can be utilized by P. donghaiense. When using G-6-P,ATP and NaHEPO4 respectively as the phosphorus source, the maximum Specific growth rate （μmax） and the maximum biomass of P. donghaiense were similar; but when using G-P as the phosphorus source, the maximum Specific growth rate （μmax） and the maximum biomass of P. donghaiense were the lowest. The results further suggest that dissolved organic phosphorus（DOP） in the nature seawater with the similar structure as the former three organic phosphorus can act as the alterative phosphorus source of the outbreak and maintaining of the red tide of Prorocentrum donghaiense.