Determination of EC50 for normal oyster larval development in extracts from bloom-forming green seaweeds

作者：Nelson Timothy A^*; Gregg Bridget C

来源：Nautilus, 2013, 127(4): 156-159.

• Crassostrea gigas
• Ulvaria obscura
• Ulva lactuca
• Allelopathy
• Harmful Algal Blooms

Blooms of ulvoid algae can decimate marine ecosystems, out-competing seagrasses and other habitat-forming species and directly killing animals due either to the production of allelo-chemicals or various effects (e.g., anoxia) associated with bloom mortality. Oyster larvae (Crassostrea gigas) are susceptible to extracts from dried ulvoids at relatively low concentrations. Here we determine a specific EC50 for extracts from the bloom-forming species Ulva lactuca and Ulvaria obscura. The EC50 for Ulva is equivalent to 0.13 gfm.L-1 while the value for Ulvaria is 0.21 gfm.L-1. Assuming moderate bloom conditions, these data suggest that an EC50 could be achieved in 5,200 to 8,500 L of seawater for each m(2) of algal bloom. Possible mechanisms for developmental toxicity include the breakdown products of DMSP (in both species), dopamine quinones (in Ulvaria only), or as yet unidentified toxins.

• 出版日期2013-12-30