A study on allelopathy effects of Margalefidinium polykrikoides on Pyrodinium bahamense

• Main Authors: Mohammad Noor, Normawaty, Al-Has, Asilah, Muhamad Shaleh, Sitti Raehanah, Darnis, Deny Susanti, Adam, Aimimuliani
• Format: Conference or Workshop Item
• Language: English
• Published: 2022
• Subjects: Q Science (General)
• Online Access: http://irep.iium.edu.my/100191/19/100191_A%20study%20on%20allelopathy%20effects%20of%20Margalefidinium%20polykrikoides.pdf; http://irep.iium.edu.my/100191/

The dinoflagellate Margalefidinium polykrikoides, a fish killer, has worldwide distribution and is associated with harmful algal blooms (HABs). To maintain the bloom, this species has the ability to cause an allelopathic effect on other phytoplankton. In this study, we investigated the allelopathy effects of M. polykrikoides on the growth of toxic dinoflagellate Pyrodinium bahamense. Allelopathy effects of M. polykrikoides were done by comparing between M. polykrikoides cultured cells and bloom collected from fields through cell-free culture filtrates method. Results showed that Pyrodinium bahamense was inhibited significantly (p<0.05) in cell-free culture filtrate of M. polykrikoides bloom but not in cell-free filtrate M. polykrikoides cultured. In addition, bi-algal culture experiment of M. polykrikoides and Pyrodinium bahamense at three different ratios, separated by a 5µm membrane to prevent direct cell contact was also conducted. The observation showed that at ratio 1:5 (100 cells mL-1 of M. polykrikoides: 500 cells mL-1 P. bahamense), P. bahamence cell number increased significantly (p<0.05) starting from Day 4. This study provides useful information on strategies to compete with other phytoplankton and form bloom to dominate the area played by M. polykrikoides