Iron requirements of the pennate diatom Pseudo-nitzschia : Comparison of oceanic (high-nitrate, low-chlorophyll waters) and coastal species

• DOI: 10.4319/lo.2006.51.5.2092
• Publication Date: 2010-07-01T18:00:35Z
• Authors: Adrian Marchetti; Maria T. Maldonado; Erin S. Lane; Paul J. Harrison
• Keywords: Nitzschia

We quantified and compared physiological parameters iron requirements of several oceanic Pseudonitzschia spp., newly isolated from the high-nitrate, low-chlorophyll waters northeast subarctic Pacific, with coastal Pseudo-nitzschia spp. centric diatom Thalassiosira oceanica at a range concentrations. In iron-replete conditions, (Fe) : carbon (C) ratios in six isolates ranged 157 µmol Fe mol C-1 to 248 C-1, no apparent differences between isolates. low all exhibited marked reductions photosynthetic efficiency, whereas extent specific growth rates varied among species. When iron-limited, :C decreased significantly species, lowest ranging 2.8 3.7 C-1. Combined faster rates, lower resulted higher iron-use efficiencies relative their congeners T. oceanica. The wide (Fe-Qhigh) iron-limited (Fe-Qlow) quotas indicates that have an extensive plasticity contents other diatoms grown similar concentrations reported literature; Fe-Qhigh Fe-Qlow for species were 46 67, they 16 43. suggest ability exhibit response enrichment events may, part, be result extraordinary capacity accumulate potentially store large amounts intracellular when are high, yet substantially reduce sustain fast well after external depleted.