1989 Fiscal Year Final Research Report Summary
Studies on Biology and Ecology of Marine Heterotrophic Dinoflagellates.
| Project/Area Number |
63560183
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
General fisheries
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| Research Institution | The University of Tokyo |
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Principal Investigator |
FUKUYO Yasuo Univ. of Tokyo, Fac. of Agriculture, Assis. Prof., 農学部, 助手 (10165318)
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| Co-Investigator(Kenkyū-buntansha) |
ISHIMARU Takashi Tokyo Univ. of Fisheries, Fac. of Fisheries Associate Professor, 水産学部, 助教授 (90114371)
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| Project Period (FY) |
1988 – 1989
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| Keywords | dinoflagellates / heterotrophic dinoflagellates / cryptomonads / Dinophysis / feeding behavior / sexual reproduction / diarrhetic shellfish poison |
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| Research Abstract |
1. Biology and ecology of heterotrophic dinoflagellates were studies using fluorescent microscope with video camera on their feeding behavior, life history and growth physiology.
2. Dinophysis fortii and D. acuminata have not only chlorophyll but also phycobilin as photosynthetic pigments. Some cells have the phycobilin only in round or rod-shaped chloroplasts and others have it all over in protoplasm including chloroplasts. As the phycobilin is quite rare pigment in dinoflagellates, it is strongly suspected that the hycobilin comes from cryptomonads or cyanobacters which are ingested into Dinophysis protoplasm by feeding.
3. D. forth and D. cuminata ingest cryptomonads into their protoplasm through pores which penetrate their valves after catching the diet on the adhesive valve surface. .
4. Particles stained by neutral-red dye can be taken into food vacuole of D. cuminata. This is the second methods of their feeding.
5. Suction of protoplasm of a small size cell by a large size cell through flagellar pores were observed during culture of D. fortii. This behavior is very similar to cell fusion in the course of sexual reproduction, but we could not clarify it because the cell after fusion died before showing any morphological change.
6. Feeding behavior of Dino hysis Rotundata. a non-photosynthetic dinoflagellate, was observed. The species chooses tintinnids as prey organism. D. rotundata inserts a suction tube to the tintinnid, sending a small amount of fluid to stop movement of the prey. Then D. rotundata suck the protoplasm of the tintinnid. The protoplasm sucked are kept in the manner of many transparent globules inside Dinophysis cell and then assimilated gradually.
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