Communicating editor: T. Motomura.
Effects of iron on the growth and minimal fluorescence yield of three marine Synechococcus strains (Cyanophyceae)
Article first published online: 16 JAN 2012
© 2012 Japanese Society of Phycology
Volume 60, Issue 1, pages 61–69, January 2012
How to Cite
Liu, S., Juneau, P. and Qiu, B. (2012), Effects of iron on the growth and minimal fluorescence yield of three marine Synechococcus strains (Cyanophyceae). Phycological Research, 60: 61–69. doi: 10.1111/j.1440-1835.2011.00636.x
- Issue published online: 16 JAN 2012
- Article first published online: 16 JAN 2012
- Received 17 November 2010; accepted 4 November 2011.
- chlorophyll fluorescence;
- minimal fluorescence yield;
Two coastal Synechococcus stains PCC 7002 and CC9311 and one oceanic strain WH8102 were cultured with 4–1000 nM Fe in Aquil medium. Compared with those under iron-replete conditions, their growth rates were significantly decreased by 59% for WH8102 at 15 nM Fe, by 37% for CC9311 at 15 nM Fe and by 57% for PCC 7002 at 4 nM Fe. Among these three strains, PCC 7002 was the most tolerant to iron limitation while WH8102 was the most sensitive to iron limitation. For each strain under the same iron concentration, the growth rates calculated from the minimal fluorescence yield and cell concentration showed no significant difference. The linear correlation was established between the minimal fluorescence yield and cell concentration although the minimal fluorescence yield per cell varied depending on the strains and iron levels. Under iron-replete conditions, the minimal fluorescence yield per cell was 100-fold higher for the phycoerythrin-lacking strain PCC 7002 than two phycoerythrin-containing strains WH8102 and CC9311. Under iron-deplete conditions, it was increased respectively by 128% and 7% for WH8102 and CC9311 but was decreased by 30% for PCC 7002. Furthermore, the minimal fluorescence yield per cell for PCC 7002 and CC9311 showed little difference throughout the light and dark diel cycle. However, it was significantly higher for WH8102 in the daytime than in the dark.