Growth responses of Microcystis ichthyoblabe Kutzing and Anabaena aphanizomenoides Forti (cyanobacteria) under different nitrogen and phosphorus conditions

• Type: Article in International Scientific Journal
• Date: 2009

Authors

Brahim Sabour (Author) Other; Mohammed Loudiki (Author) Other; Vitor Vasconcelos (Author) FCUP

Journal

Title: Chemistry and Ecology

Vol. 25

Pages: 337-344

ISSN: 0275-7540

Publisher: Taylor & Francis

Indexing

ISI Web of Knowledge - 18 Citations

Scopus - 20 Citations

Scientific classification

FOS: Natural sciences > Biological sciences

Other information

Authenticus ID: P-003-PD4

DOI: 10.1080/02757540903193130

Abstract (EN): Experiments in batch cultures under controlled sub-optimal light and temperature conditions were undertaken to determine the effect of nitrogen, phosphorus and N:P ratios on the growth of Microcystis ichthyoblabe Kutz. 1843 and Anabaena aphanizomenoides Forti 1912, two toxic cyanobacteria forming blooms from Oued Mellah lake. Phosphorus experiments show that densities of M. ichthyoblabe and A. aphanizomenoides increased differently in the various media. Under non-limiting phosphorus conditions (1000-6960gP l-1), 5-7 days of exponential growth was observed, while in P-free and in P-deficient media (0-500gl-1), the growth was limited. As with phosphorus experiments, cell growth of M. ichthyoblabe was substantially favoured under high nitrate concentrations (50-84mgl-1), whereas cultures under N-free or N-deficient conditions (0-10mgl-1) seemed to be limited. Nitrate-nitrogen at all tested concentrations was not limiting for the growth of A. aphanizomenoides cultures, which reached high density during an exponential growth of 8-9 days. Under low nitrate concentrations (0-5mgl-1), an increased number of heterocysts was observed. There was a markedly diminished growth with the lower N:P ratio experiments (5) only for Microcystis and on the highest N:P ratio experiments (epsilon 30) for both Microcystis and Anabaena aphanizomenoides.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8