Fluorescent proteins in corals have been re-ported to have photoprotective function for algal sym-bionts, though it remains controversial whether the coral fluorescent proteins are actually photoprotective. Green (Gs) and brown (B) morphs of the coral Galaxea fascicularis have different contents of green fluorescent protein (GFP). To understand the function of GFP in the stress responses of the coral, we exposed polyps isolated from B and Gs morph colonies to medium or strong light (200 and 1000μmol quanta m-2s-1) at 26 or 32°C for 6h. Polyps were then allowed to recover for 6h under dim light. Although the GFP content was markedly different between Gs and B morphs, in hospite zooxanthellae in polyps of both morphs showed similar decreases in photochemical efficiency (Fv/Fm) after strong light treat-ment at normal or high temperature. Isolated zooxanthellae of both morphs showed similar decrease in the photo-chemical efficiency under light stress, indicating that they had similar tolerance to light stress. The present results suggest that fluorescent protein does not increase the tolerance of polyps to strong light and high temperature stress in G. fascicularis and that further studies are nec-essary to elucidate the function of GFP in this coral.
The response of Acanthaster planci or crown-of-thorns starfish (COTS) to intracoelomic injection of hypersaline solutions was investigated to establish its potential application as A. planci population control es-pecially during an outbreak. Adult A. planci when inverted had a normal righting response time (in seconds) of 163±1 (mean±SE; N＝298). Injection of concentrated salt solutions led to negative effects on adult A. planci. The spines bent down, body collapsed and the starfish became comatose and died after 24-hours. The higher the salt concentration, the higher is the % comatose indivi-duals. In addition, comatose specimens failed to recover with time. Mortality was highest at the highest treatment concentration with LC90 of 285.3 and LC99 of 383.2ppt. The effects of time, salt concentration and its interaction (salt concentration x time) were significant (p＝0.00). The ionic and osmotic disruption of the coelomic fluid can seriously affect physiological functions of the organism including neuromuscular activity. Thus, in the control of A. planci, concentrated salt solution can be used as a cheaper alternative to dry acid, acetic acid or ammonium hydroxide, all of which are expensive, may not be locally available and not environment friendly.