EU-US ECOHAB. EC-NSF Cooperative Activity in Environmental Res: Mating Incompatibility Among Toxic and Non-Toxic Populations of Alexandrium: Ecological and Practical Implications

欧盟-美国ECOHAB。

• 批准号: 0402707
• 负责人: Donald Anderson
• 金额: --
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-05-01 至 2010-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0402707&HistoricalAwards=false
• 关键词: EU; US; ECOHAB.; EC; NSF

Harmful algal blooms (HABs) are a serious and growing problem in the US and the world. Among the multiple poisoning syndromes linked to HABs, Paralytic Shellfish Poisoning (PSP) is arguably the most widespread and significant on a global basis. Dinoflagellates within the genus Alexandrium (and in particular within the tamarensis and minutum species complexes) are responsible for many of these PSP outbreaks in the US and in Europe. Several characteristics of the temporal and spatial pattern of Alexandrium species are noteworthy. First, over the last several decades, the distribution of species within both complexes has expanded geographically as a result of natural and human-assisted dispersal mechanisms. Second, there are both toxic and non-toxic varieties of certain species within each of these complexes, and sometimes these bloom in relatively close proximity to each other. This latter observation is particularly noteworthy given recent results, which demonstrate that toxic, and non-toxic strains of A. tamarense can mate and produce resting cysts, but the cells that germinate from these cysts quickly die as they attempt to divide. A reproductive barrier thus exists for at least some strains of this species. The overall objective of this project is to investigate mating compatibilities among toxic and non-toxic members of the tamarensis and minutum species complexes of Alexandrium. This will involve a combination of laboratory and field studies in a direct collaboration between US and EU partners under the EC-NSF Cooperative Activity in Environmental Research. Specific objectives are to: 1) Establish and characterize additional toxic and non-toxic Alexandrium cultures from the northeastern U.S. and Europe; 2) Determine mating compatibility between toxic and non-toxic strains of A. tamarense and A. minutum; 3) Identify a genetic marker to distinguish between toxic and non-toxic minutum; 4) Develop methods to determine the toxic/non-toxic genotype of planktonic cells and cysts; 5) Determine mating selectivity of toxic and non-toxic A. minutum and A. tamarense strains; 6) Participate in European field surveys to map Alexandrium populations in the plankton and sediments; and 7) Employ growth rate, grazing rate and mating preference data to model the outcome of a variety of invasion scenarios and to evaluate the potential of introduced non-toxic Alexandrium species as a bloom control or mitigation strategy.The scientific merits of the proposed study are significant, as the mating incompatibilities to be explored may explain observed distributions of toxic and non-toxic Alexandrium species throughout the world and relate directly to the potential success of an invasion of one toxin-type into the domain of the other, such as through natural currents and storms, or ballast water discharge. The broader impacts are also significant. HABs represent a serious threat to public health and efficient utilization of coastal resources. In addition to practical implications with respect to species dispersal via ballast water discharge or other human-assisted means, a novel bloom control or mitigation strategy of potential value to society will be investigated whereby a non-toxic strain of Alexandrium could be introduced to an area subject to toxic outbreaks in a manner analogous to the release of sterile males to control insect pests. Other broad impacts include strengthening the EU-US HAB network of scientists, communicating results via conference presentations, scientific publications, and articles in the popular press, and training and education of young scientists. In the latter context, students and postdoctoral investigators from both the US and the EU will work in the PI's laboratory on this project, supported by outside fellowships, EU funds, internal WHOI funds (Summer Student Fellowships, Minority Traineeships), and REU (Research Opportunities for Undergraduates) support, for which proposals will be submitted. The PI has always placed a high priority on the integration of research and education, and this project will be no exception.

有害藻华(HAB)在美国和世界上是一个严重且日益严重的问题。在与赤潮有关的多种中毒综合征中，麻风性贝类中毒(PSP)可以说是全球范围内最广泛和最重要的。亚历山大藻属内的甲藻(特别是在他玛藻属和细小藻属复合体中)是美国和欧洲许多PSP爆发的原因。亚历山大藻物种的时间和空间格局的几个特征值得注意。首先，在过去几十年中，由于自然和人工辅助的扩散机制，两个复合体内物种的分布在地理上有所扩大。其次，在这些复合体中，既有有毒的，也有无毒的某些物种的品种，有时这些物种在相对较近的地方开花。考虑到最近的结果，后一种观察结果尤其值得注意，这些结果表明，有毒和无毒的塔玛依菌株可以交配并产生休眠的包囊，但从这些包囊中萌发的细胞在试图分裂时很快死亡。因此，至少该物种的某些品系存在生殖障碍。这个项目的总体目标是调查亚历山大藻有毒和无毒的成员与亚历山大藻细小物种复合体之间的交配兼容性。这将涉及在欧共体-NSF环境研究合作活动下，美国和欧盟合作伙伴之间直接合作的实验室和实地研究相结合的工作。具体目标是：1)建立和鉴定来自美国和欧洲东北部的更多有毒和无毒的亚历山大藻培养物；2)确定有毒和无毒的塔玛亚历山大藻和微小亚历山大藻的交配亲和性；3)确定区分有毒和无毒微小亚历山大藻的遗传标记；4)开发确定浮游细胞和包囊的有毒/无毒基因型的方法；5)确定有毒和无毒的微小亚历山大藻和塔玛亚历山大藻菌株的交配选择性；6)参加欧洲的实地调查，绘制浮游生物和沉积物中的亚历山大藻种群图；7)使用生长率、放牧率和交配偏好数据来模拟各种入侵情景的结果，并评估引入的无毒亚历山大藻物种作为水华控制或缓解策略的潜力。拟议的研究具有重大的科学价值，因为要探索的交配不亲和性可能解释观察到的有毒和无毒亚历山大藻物种在世界各地的分布，并直接与一种毒素类型入侵另一种毒素类型的领域的潜在成功有关，例如通过自然水流和风暴或压载水排放。更广泛的影响也是显著的。赤潮对公众健康和沿海资源的有效利用构成严重威胁。除了通过压载水排放或其他人工辅助手段传播物种的实际影响外，还将研究一种对社会具有潜在价值的新的水华控制或缓解战略，根据该战略，可将一种无毒的亚历山大藻菌株引入易发生有毒疫情的地区，其方式类似于释放不育雄性以控制虫害。其他广泛的影响包括加强欧盟-美国的HAB科学家网络，通过会议报告、科学出版物和大众媒体上的文章交流成果，以及对青年科学家的培训和教育。在后一种情况下，来自美国和欧盟的学生和博士后研究人员将在PI的实验室从事这一项目，得到外部奖学金、欧盟资金、WHOI内部资金(暑期学生奖学金、少数族裔实习生)和REU(本科生研究机会)的支持，并将提交提案。科协历来高度重视研究与教育的融合，这个项目也不会例外。