Algicidal and growth-inhibiting bacteria associated with seagrass and macroalgae beds in Puget Sound, WA, USA

作者：Inaba Nobuharu^*; Trainer Vera L^*; Onishi Yuka; Ishii Ken Ichiro; Wyllie Echeverria Sandy; Imai Ichiro^*

来源：Harmful Algae, 2017, 62: 136-147.

DOI：10.1016/j.hal.2016.04.004

• Algicidal bacteria
• Heterosigma
• Alexandrium
• Seagrass
• Harmful algal blooms (HABs)

The algicidal and growth-inhibiting bacteria associated with seagrasses and macroalgae were characterized during the summer of 2012 and 2013 throughout Puget Sound, WA, USA. In 2012, Heterosigma akashiwokilling bacteria were observed in concentrations of 2.8 x 10(6) CFU g(-1) wet in the outer organic layer (biofilm) on the common eelgrass (Zostera marina) in north Padilla Bay. Bacteria that inhibited the growth of Alexandrium tamarense were detected within the biofilm formed on the eelgrass canopy at Dumas Bay and North Bay at densities of similar to 10(8) CFU g(-1) wet weight. Additionally, up to 4100 CFU mL(-1) of algicidal and growth-inhibiting bacteria affecting both A. tamarense and H. akashiwo were detected in seawater adjacent to seven different eelgrass beds. In 2013, H. akashiwo-killing bacteria were found on Z. marina and Ulva lactuca with the highest densities of similar to 10(8) CFU g(-1) wet weight at Shallow Bay, Soda Island. Bacteria that inhibited the growth of H. akashiwo and A. tamarense were also detected on Z. marina and Z japonica at central Padilla Bay. Heterosigma akashiwo cysts were detected at a concentration of 3400 cysts g(-1) wet weight in the sediment from Westcott Bay (northern San Juan Island), a location where eelgrass disappeared in 2002. These findings provide new insights on the ecology of algicidal and growth-inhibiting bacteria, and suggest that seagrass and macroalgae provide an environment that may influence the abundance of harmful algae in this region. This work highlights the importance of protection and restoration of native seagrasses and macroalgae in nearshore environments, in particular those regions where shellfish restoration initiatives are in place to satisfy a growing demand for seafood.

• 出版日期2017-2