Growth and reproductive responses of Laminaria longicruris (Laminariales, Phaeophyta) to nutrient enrichment
A series of comparative culture experiments were conducted in order to determine responses of Laminaria longicruris male and female gametophytes and juvenile sporophytes to several temperatures (5, 10, 15, 20 °C), light levels (10, 35, 75 µmol m−2 s−1) and media nitrogen concentrations (0, 20, 100 µM ammonium-nitrogen). Responses were measured as numbers of male and female gametophytes producing gametangia and number of sporophytes produced following fertilization. Both male and female gametogenesis was reduced at 5 and 20 °C versus 10 and 15 °C. At 20 °C gametogenesis inhibition was greater with higher levels of ammonium-nitrogen concentration (100 µM). Sporophyte production was more sensitive to light, temperature and nitrogen concentration than gametogenesis. Production of sporophytes was inhibited completely at 20 °C. At lower temperatures, increasingly higher nutrient concentrations produced greater inhibition of production of sporophytes.
Digital Object Identifier (DOI)
Yarish, C., C.A. Penniman, and B. Egan. 1990. Growth and reproductive responses of Laminaria longicruris (Laminariales, Phaeophyta) to nutrient enrichment. Proceedings of the Thirteenth International Seaweed Symposium, Vancouver, B.C., Canada. Hydrobiologia 204/205:505-511.