Physiology and ecology of ciguatera causative dinoflagellates

雪卡致病甲藻的生理学和生态学

基本信息

批准号：
02660192
负责人：
ISHIMARU Takashi
金额：
$ 1.47万
依托单位：
Tokyo University of Fisheries
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1990
资助国家：
日本
起止时间：
1990 至 1991
项目状态：
已结题

项目摘要

Distribution of benthic dinoflagellates including ciguatera causative organisms were examined in Akajima Island, Kerama Islands, Okinawa, Japan. Prorocentrum species including a new species occupied high percentage of density compared with others. Gambierdiscus toxicus known as a main producer of CTX and MTX was rater low in the density, but its maximum cell density was a thousand times higher than that examined at Okinawa Island and Ishigaki Island. The new species recembles Prorocentrum emarginatum but the difference in the valval shape and depression on the valve surface were confirmed by scanning electron microscopic observations.A new type of fluorometer was made to monitor the growth of benthic dinoflagellates. A culture tube is placed in the integrating sphere which diffuse both excitation light and in vivo fluorescence. Thus the fluorescence is monitored without agitation. The performance of integrating-sphere-fluorometer (ISF) was tested for cultures of a benthic diatom and dinoflagellates, and good correlations were obtained between in vivo fluorescence and extracted chlorophyll amounts.Effects of light, temperature and exudate of macroalgae on growth of benthic Prorocentrum species were examined. Their optimum growth were observed between 1.1-1.4x10^<16>quanta cm^<-2> sec^<-1> and 25.5-30.7 ﾟC, respectively. The exudate released from the surface of Zonaria stipitata and Distromium decumbens (Phaeophyceae) promoted the growth of P. lima, P. sp. and P. emarginatum but P. concavum. On the contrary, the exudate of Turbinaria ornata, on which abundant adhesion of Prorocentrum was observed in the field, rather disturbed the growth of four species. From these results, benefits of their adhesion to the host macroalge were thought as a shading from high irradiance besides the supply of growth promoting substances.

在日本冲绳庆良间群岛的阿卡岛，对包括雪卡藻在内的底栖甲藻的分布进行了检查，其中包括一种新物种，与其他已知的 CTX 和 MTX 生产者相比，其密度百分比较低。密度，但其最大细胞密度比在冲绳岛和石垣岛检查的新物种高出一千倍。通过扫描电镜观察证实了原甲藻的瓣膜形状和瓣膜表面凹陷的差异。制作了一种新型荧光计来监测底栖甲藻的生长。将培养管放置在积分球中，使两者扩散。因此，无需搅拌即可监测荧光。测试了底栖硅藻培养物的积分球荧光计 (ISF) 的性能。检测了光、温度和大型藻类分泌物对底栖原甲藻生长的影响，观察到它们的最佳生长在1.1-1.4x10^16量子厘米之间。 ^<-2>秒^<-1>和25.5-30.7°C，分别为渗出液。 Zonaria stipitata 和 Distromium decumbens (Phaeophyceae) 的表面促进了 P. lima、P. sp. 和 P. emarginatum 的生长，但 P. concavum 的生长相反，在其上观察到大量的 Prorocentrum 的附着。从这些结果来看，它们对宿主巨藻的粘附的好处被认为是一种阴影。除了提供生长促进物质外，还应避免高辐照度。