Alexander Ebbing1,2, Joshua Masel1, Haik van Exel1, and Klaas Timmermans2
1Hortimare BV, Altonstraat 25A, 1704 CC Heerhugowaard, The Netherlands
2 Department of Estuarine and Delta Systems, NIOZ Royal Netherlands Institute for Sea Research, PO Box 140, 4401 NT Yerseke, the Netherlands
The family of Laminariaceae have a heteromorphic lifecycle that alternates between haploid gametophytes and diploid sporophytes. In contrast to the macroscopic sporophytes, the haploid gametophytes are of microscopic nature and delayed gametophytes are especially understudied. Delayed gametophytes are gametophytes that have been growing vegetatively, as undifferentiated filamentous cells, for prolonged periods of time, without sexual reproduction. Gametophytes that delay their reproduction for more than a year, transgress any seasonally induced reproduction and are called multiannual delayed (MAD) gametophytes. Studies revolving around MAD gametophytes are gaining more and more attention since they play a key role in large scale kelp aquaculture. Novel insights from these studies could not only progress the utilization of MAD gametophytes in kelp aquaculture, they can also generate key insights into the role of MAD gametophytes in their natural environment. An environment which up until now is still poorly described. For example, there seems to be a strong inverse correlation between the density of female gametophytes in a culture and the reproductive success of this culture. What is the mechanism behind this inverse correlation, and how does this translate to the natural environment of MAD gametophytes? During this presentation we will delve deeper into this secret life of MAD gametophytes, their (a)biotic lifecycle controls and their interaction with the natural environment.