【摘要】 为阐明红色赤潮藻(Akashiwo sanguinea)对氮营养条件的适应机制,本研究在不同氮浓度条件下对红色赤潮藻进行一次性培养,系统研究了氮浓度对红色赤潮藻生长、休眠孢囊形成和细胞生源要素组成的影响。结果显示,红色赤潮藻生长率随着初始氮浓度的增加而增大, 200μmol/L氮添加组生长率最大,为0.79/d。不同氮处理组细胞形态存在差异,低氮条件下藻细胞个体变小。培养第6天,各氮处理组均观察到休眠孢囊,且随着培养时间的延长,孢囊数量逐渐增多;50μmol/L氮添加组孢囊形成率最高,为2.95%±0.16%。氮浓度对红色赤潮藻细胞生源要素组成有显著影响,红色赤潮藻胞内碳、氮含量随氮浓度的升高而增加,其C:N:P也随氮浓度的增加而增加。红色赤潮藻生长过程中,加氮处理组细胞在指数期碳、氮、磷含量较低,稳定期含量较高;相关性分析表明,红色赤潮藻胞内碳、氮、磷含量与藻生长率之间呈显著负相关关系(P <0.05)。不同氮浓度对红色赤潮藻的生长、休眠孢囊形成和藻细胞生源要素组成有显著影响,为揭示红色赤潮藻对氮营养条件的适应机制提供参考。更多还原

【Abstract】 To classify the adaption mechanism of Akashiwo sanguinea to nitrogen, a batch culture of A. sanguinea was carried out in different nitrogen concentrations. Changes in growth, resting cyst formation, and biogenic element composition were studied. The results show that the specific growth rate of A. sanguinea increased with the increasing of nitrogen addition. The highest specific growth rate 0.79/d was achieved in 200 μmol/L N-added treatment. Different cellular morphology was shown in different nitrogen conditions. Under low nitrogen conditions, the individual algae cells become smaller. On the 6 th day of culture, resting cysts were observed in each nitrogen treatment group, and the number gradually increased with the extension of the culture time; the 50 μmol/L N-added treatment had the highest cyst formation rate at 2.95%±0.16%. Furthermore, the biogenic element composition changed significantly under different nitrogen concentrations. The C and N content in A. sanguinea increased with the increase of nitrogen concentration, and its C:N:P also increased with the increase of nitrogen concentration. During the growth of A. sanguinea, the cellular content of C and N was lower in the exponential phase, while the content was higher in the stationary phase. The Pearson’s correlation analysis indicated that cellular C, N, and P contents correlated negatively with the growth rate of A. sanguinea(P<0.05). Different nitrogen concentrations had significant effects on the growth, resting cyst formation, and biogenic elements composition of A. sanguinea. This study provided a reference for revealing the adaptation mechanism of A. sanguinea to a different condition of nitrogen nutrition.更多还原