Sexual and asexual production of planulae by corals from the central Great Barrier Reef

Collections of two hermatypic (zooxanthellate) species of corals (Seriatopora hystrix and Acropora palifera) and two ahermatypic (non-zooxanthellate) species of corals (Tubastrea diaphana and Tubastrea coccinea) were made between September and November, 1984 in the central Great Barrier Reef.

Fragments of individual colonies were maintained in 1 litre containers of unaerated sea water at room temperature. The water was changed daily and checked for the presence of planulae, which were transferred to a separate container and kept alive for up to 7 days. Only actively swimming planulae were selected for electrophoresis. Adult tissue samples were frozen at -80°C, and tissue extracts for electrophoresis were prepared from fresh or frozen material.

All adults and planulae were homogenised on cold plates (<4°C), except the small planulae of Seriatopora hystrix, which were homogenised at room temperature to avoid the diluting effects of condensation. All adults were assayed for the enzymes malate dehydrogenase (MDH, EC 1.1.1.37), 6-phosphogluconate dehydrogenase (6-PGD, EC 1.1.1.44) and superoxide dismutase (SOD, EC 1.15.1.1.) on buffer 5 of Selander et al. (1971), and phosphoglucose isomerase (PGI, EC 5.3.1.9) and phosphoglucomutase (PGM, EC 2.7.5.1) on buffer 9 of Selander et al. (1971). Individual planulae were assayed on only one buffer system and stained for a maximum of three enzymes.

Selander RK, Smith MH, Yang SY, Johnson WE and Gentry JB (1971) Biochemical polymorphism and systematics in the genus Peromyscus. I. Variation in the old-field mouse (Peromyscus polionotus). Stud. Genet., Austin, Tex. 6, 49-90. (Univ. Tex. Publ. No. 7103).