氮、硅限制对赤潮藻扁面角毛藻休眠孢子形成的影响

休眠孢子的形成对于赤潮藻种群的保存、延续以及分布扩散等均具有重要的意义。通过单因子营养限制研究氮、硅对赤潮藻扁面角毛藻（Chaetoceros compressus）休眠孢子形成的影响，结果表明：培养基中氮的初始浓度对休眠孢子的出现时间有一定影响。氮的初始浓度越低，休眠孢子出现的时间越早：反之，氮的初始浓度越高，休眠孢子出现的时间越晚。氮缺乏是硅藻形成休眠孢子的必需条件之一，当培养基中氮含量低于10μmol·L^-1时，扁面角毛藻可以形成休眠孢子。氮缺乏诱发的休眠孢子的形成需要大量的硅，当培养基中硅含量低于23μmol·L^-1时，即使氮缺乏，扁面角毛藻也几乎不再继续形成休眠孢子。这说明硅藻休眠孢子的形成不仅受氮浓度的影响，还与硅浓度有关。

Effects of Nitrogen and Silicon Limitation on Resting Spore Formation of Red Tide-causing Alga Chaetoceros compressus (Bacillariophyta)

The formation of resting spores plays an important role in population succession, conservation, distribution and dispersal of red tide-causing alga. We studied the effects of nitrogen （N） and silicon （Si） limitation on the resting spore formation of Chaetoceros compressus. Resting spores formed earlier and developed faster under low N concentration （50 μmol·L^-1） than under high N concentration （100 μmol·L^-1）, with no resting spores observed under 500μmol·L^-1 N concentration. N depletion is one of the indispensable conditions for the formation of resting spores of diatoms. Resting spores can be formed in C. compressus species with N concentration reduced to lower than 10μmol·L^-1. As well, abundant Si is needed for the formation of resting spores induced by N depletion. No resting spores of C. compressus formed with Si concentrations lower than 23μmol·L^-1, even with sufficiently low N concentration. Thus, the formation of resting spores in diatoms is related to not only N but also Si concentration.