Response of gametophytes of Ecklonia radiata (Laminariales) to temperature in saturating light

Gametophytes of E. radiata (C.Ag.)J.Ag. from two New Zealand locations with different field temperature ranges were exposed to temperatures of 5 degree to 26 degree C in saturating light. Plants from Goat Island Bay (Lat. 36 degree 16'S, Long. 174 degree 48'E) grew in 9.3 degree to 25 degree C and reproduced in 9.3 degree to 24 degree C. There was no growth at 8 degree C and plants died at 26 degree C. Plants from the cooler location, Houghton Bay (Lat. 41 degree 20'S, Long. 174 degree 40'E), grew from 8 degree to 24 degree C and reproduced up to 15 degree C but not at 21.5 degree C. The plants did not grow at 6 degree C and diet at 26 degree C. The timing of the first cell division and subsequent growth rate were retarded close to the upper and lower tolerance limits.