Use of amplified fragment length polymorphism (AFLP) as a new tool to explore the invasive green algaCaulerpa taxifoliain Australia

Caulerpa taxifoliais a high profile introduced alga in the Mediterranean Sea and California. It is native to tropical and subtropical regions of Australia. However, during 2000/01, 7 locations with abundantC. taxifoliawere discovered in temperate waters around Sydney. To overcome limitations of resolution in previous studies using ITS (internal transcribed spacer) rDNA sequencing, we developed amplified fragment length polymorphism (AFLP) markers forC. taxifolia, using 4 primer combinations. With this technique we found a close relationship between isolates from Moreton Bay (native) and Lake Conjola (introduced). The Mediterranean samples, which previously could not be separated from the other isolates, formed a discrete cluster supported by high bootstrap values. AFLP had greatly improved resolution over other molecular markers, making it a promising technique for further studies on the population structure ofC. taxifoliaand the assignment of source populations.