1996 年 62 巻 5 号 p. 723-726
For the early harvest of Undaria undarioides (Yendo) Okamura, research was carried out to know the most suitable time and suspending depth in outplanting of seedlings, at Tanabe Bay in Wakayama Prefecture, Japan. The seedlings were outplanted in the sea on November 15 and December 5 and 15 1991, and in suspending depth of 0.5m, 1.5m and 2.5m. The blade size (blade length and width) and maturation by formation of zoosporangial sori were observed every 10 days. The seedlings which were outplanted at a depth of 0.5m on November 15 grew to the minimum commercial size (above the average blade length of more than 35cm) by the middle of January. U. undarioides could be harvested one month earlier than the usual outplant seedlings, due to early outplanting in the sea water temperature of less than 20°C. In the early outplanted seedlings, the blade grew wider and maturation was earlier than the usual outplanted seedlings.