Succession and toxicity of Microcystis and Anabaena (Dolichospermum) blooms are controlled by nutrient-dependent allelopathic interactions

Author(s)

Chia, Mathias A. ^{[1, 2]} ; Jankowiak, Jennifer G. ^[2] ; Kramer, Benjamin J. ^[2] ; Goleski, Jennifer A. ^[2] ; Huang, I-Shuo ^[3] ; Zimba, Paul V. ^[3] ; Bittencourt-Oliveira, Maria do Carmo ^[1] ; Gobler, Christopher J. ^[2]

Affiliation

^[1] Univ Sao Paulo, Luiz de Queiroz Coll Agr, Dept Biol Sci, Av Padua Dias 11, BR-13418900 Piracicaba, SP - Brazil

^[2] SUNY Stony Brook, Sch Marine & Atmospher Sci, Southampton, NY 11968 - USA

^[3] Texas A&M Univ, CCS, Corpus Christi, TX 78412 - USA

• Document type: Journal article
• Source: HARMFUL ALGAE; v. 74, p. 67-77, APR 2018.
• Web of Science Citations: 12

Abstract

Microcystis and Anabaena (Dolichospermum) are among the most toxic cyanobacterial genera and often succeed each other during harmful algal blooms. The role allelopathy plays in the succession of these genera is not fully understood. The allelopathic interactions of six strains of Microcystis and Anabaena under different nutrient conditions in co-culture and in culture-filtrate experiments were investigated. Microcystis strains significantly reduced the growth of Anabaena strains in mixed cultures with direct cell-to-cell contact and high nutrient levels. Cell-free filtrate from Microcystis cultures proved equally potent in suppressing the growth of nutrient replete Anabaena cultures while also significantly reducing anatoxin-a production. Allelopathic interactions between Microcystis and Anabaena were, however, partly dependent on ambient nutrient levels. Anabaena dominated under low N conditions and Microcystis dominated under nutrient replete and low P during which allelochemicals caused the complete suppression of nitrogen fixation by Anabaena and stimulated glutathione S-transferase activity. The microcystin content of Microcystis was lowered with decreasing N and the presence of Anabaena decreased it further under low P and high nutrient conditions. Collectively, these results indicate that strong allelopathic interactions between Microcystis and Anabaena are closely intertwined with the availability of nutrients and that allelopathy may contribute to the succession, nitrogen availability, and toxicity of cyanobacterial blooms. (C) 2018 The Authors. Published by Elsevier B.V. (AU)

• FAPESP's process: 13/11306-3 - The Effects of anatoxin-a and cylindrospermopsin at different nitrogen concentrations and photon irradiances on the physiology of Microcystis aeruginosa (Cyanobacteria) and Scenedesmus acuminatus (Chlolrophyta)
• Grantee: Mathias Ahii Chia
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 14/26898-6 - Unravelling some physiological and molecular processes involved in the allelopathic interactions between toxic and non-toxic phytoplankton
• Grantee: Mathias Ahii Chia
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor