分别以高氮（摩尔C／N=8．5）、低氮（c／N=12．7）和氮添加（C／N=9．6）亚心形四爿藻（Tetraselmissubcordiformis）喂食安氏伪镖水蚤（Pseudodiaptomusannandalei）的幼体和成体，研究了此水蚤在不同氮条件下的生长、发育和摄食。随着藻细胞C／N比值的升高，安氏伪镖水蚤的生长速率从（0．067±0．001）／d减缓到（0．056±0．001）／d，同时，高氮条件下，幼体分别发育5d和18d后进入桡足幼体期和成体期，氮添加实验组与之相仿，低氮条件下则推迟到第8天进入桡足幼体期。随着藻细胞C／N比值的升高，安氏伪镖水蚤各个时期个体的氮含量显著降低，存活率也随之降低。处于高氮或氮添加条件下的无节幼体、桡足幼体和成体的氮摄食率[（0．53—0．95）×10^-4mgN／（ind．h）]均比低氮条件[（0．32—0．6）×10-4mgN／（ind-h）]要高，但仅成体的碳摄食率在高氮条件下达（8．11±1．21）×10^-4mgC／（ind．h），明显高于低碳条件下的（7．54±0．35）mgC／（ind．h）。结果表明：氮缺乏对安氏伪镖水蚤的生长发育和摄食等均有明显的抑制作用。氮添加条件下的饵料仅部分逆转这种抑制作用，暗示安氏伪镖水蚤的生长和摄食除受氮元素的直接限制外，还可能由于饵料在低氮时缺乏某些化合物而受限。%Fed on cells of Tetraselmis subcordiformis with high nitrogen content （HN, molar C/N=8.5）, low nitrogen content （LN, C/N=12.7） and with short-term addition of nitrogen after culture in f/2 medium without N （AN, C/N=9.6）, the Growth, development and ingestion of Pseudodiaptomus annandalei were investigated. With the increase of C/N of algal cells, growth rate ofP. annandalei decreased from （0.067±0.001） to （0.056±0.001） d-1. Nauplii entered into copedites or maturation on Day 5 or 18 after birth under HN condition. Under LN condition, they developed into copedites on Day 8. N contents of nauplii, copedites and adults of P. annandalei decreased with the increase of C/N of algal cells. So did the sur- vivorship. P. annandalei of all three life stages under HN or AN conditions had higher ingestion rates in terms of N [（0.53--0.95）× 10-4mgN/（ind.h）] than those under LN condition [（0.32--0.6）×10-4mgN/（ind.h）]. However, only adults un- der HN had higher C ingestion rate than their counterparts under LN condition [（8.11±1.21）×10-4 VS. （7.54±0.35）mgC/（ind.h）]. N deficiency significantly suppressed the growth, development and ingestion rate in P annandalei. The short-term addition of N partly reversed the suppression by LN.
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