Study on Dormancy of Dinoflagellate Cysts

Research Project

Project/Area Number	62480069
Research Category	Grant-in-Aid for General Scientific Research (B)
Allocation Type	Single-year Grants
Research Field	General fisheries
Research Institution	The University of Tokyo
Principal Investigator	HIRANO Reijiro The University of Tokyo, Professor, 農学部, 教授 (20011819)
Co-Investigator(Kenkyū-buntansha)	OGATA Takehiko Kitasato University, Associate Professor, 水産学部, 助教授 (00104521) ISHIMARU Takashi The University of Tokyo, Assistant Professor, 海洋研究所, 助手 (90114371) FUKUYO Yasuwo The University of Tokyo, Assistant Professor, 農学部, 助手 (10165318)
Project Period (FY)	1987 – 1988
Project Status	Completed (Fiscal Year 1988)
Budget Amount *help	¥7,000,000 (Direct Cost: ¥7,000,000) Fiscal Year 1988: ¥2,000,000 (Direct Cost: ¥2,000,000) Fiscal Year 1987: ¥5,000,000 (Direct Cost: ¥5,000,000)
Keywords	dinoflagellate / Protogonyaulax / cyst / zygote / dormant of cyst / シストの発芽 / プロトゴニオラックス
Research Abstract	1. Occurrence of swimming cells and zygotes of Protogonyaulax tamarensis and P. catenella, and number of new resting cysts transformed from the zygotes are monitored regularly together with environmental factors at Ofunato Bay, Iwate Prefecture. 2. Linear regression analysis does not show any significant relation between the occurrence of Protogonyaulax spp. and environmental factors. 3. Germination of resting cysts is more synchronized when they are kept for longer period at constant temperature. 4. Cysts germinate within shorter incubation period when they are kept at 15 oC constantly. 5. Appearance of cysts changes along with progression of incubation at constant temperature. Most prominent difference are: disappearance of red body in cyst protoplasm, aggregation of starch granule at the center, occurrence of brownish pigment. Formation of chloroplasts and separation of protoplasm membrane from cyst cell wall follows to these change. 6. Cyst obtains germination ability when chloroplasts are formed inside protoplasm.