Are some bacteria toxic for marine algae?

It was observed in vitro that some bacteria from different origins, including the sea, are capable of inhibiting the growth of several marine algae. However, there is too much difference between in vitro experiments and in situ environmental conditions to assume that bacterial poisons may rule a great deal of algac-bacteria relationships in the sea as a whole. In the author's opinion the importance of bacterial poison is limited to special and rare instances.