Showing papers by "Patricia A. Tester published in 1999"

The phylogenetic relationship of pfiesteria piscicida, cryptoperidiniopsoid sp. amyloodinoum ocellatum and a pfiesteria‐like dinoflagellate to other dinoflagellates and apicomplexans

Abstract: The taxonomic relationship between heterotrophic and parasitic dinoflagellates has not been studied extensively at the molecular level. In order to investigate these taxonomic relationships, we sequenced the small subunit (SSU) ribosomal RNA gene of Pfiesteria piscicida (Steidinger et Burkholder), a Pfiesteria-like dinoflagellate, Cryptoperidiniopsoid sp., and Amyloodinium ocellatum (Brown) and submitted those sequences to GenBank. Pfiesteria piscicida and Cryptoperidiniopsoid sp. are heterotrophic dinoflagellates, purportedly pathogenic to fish, and A. ocellatum, a major fish pathogen, has caused extensive economic losses in both the aquarium and aquaculture industries. The pathogenicity of the Pfiesteria-like dinoflagellate is unknown at this time, but its growth characteristics and in vitro food preferences are similar to those of P. piscicda. The SSU sequences of these species were aligned with the other full-length dinoflagellate sequences, as well as those of representative apicomplexans and Perkinsus species, the groups most closely related to dinoflagellates. Phylogenetic analyses indicate that Cryptoperidiniopsoid sp., P. piscicida, and the Pfiesteria-like dinoflagellate are closely related and group into the class Blastodiniphyceae, as does A. ocellatum. None of the species examined were closely related to the apicomplexans or to Perkinsus marinus, the parasite that causes “Dermo disease” in oysters. The overall phylogenetic analyses largely supported the current class and subclass groupings within the dinoflagellates.

Effects of N:P:Si ratios and zooplankton grazing on phytoplankton communities in the northern Adriatic Sea. I. Nutrients, phytoplankton biomass, and polysaccharide production

Abstract: Effects of N:P:Si-ratios and zooplankotn grazing on phytoplankton communities in the northern Adriatic Sea. I. Nutrients, phytoplankton, biomass and polysaccharide production

Preface the importance of understanding the molecular, cellular, and ecophysiological bases of harmful algal blooms

Abstract: In clear recognition of their concern for environmental quality and human health, the Phycological Society of America and the U.S. Department of Agriculture funded the symposium, ‘‘Molecular, Cellular, and Ecophysiological Bases of Noxious and Harmful Algal Blooms,’’ held on 5 August 1998 during the 52nd Annual Meeting of the Phycological Society of America in Flagstaff, Arizona. Sixteen scientists from disciplines ranging from methodological development to the study of algal molecular, cellular, and system-level ecological processes accepted invitations to present oral and/or poster papers. The symposium provided a unique forum for a diverse group of researchers to: (1) be advised of the current level of understanding of molecular, cellular, and ecophysiological processes that regulate harmful algal growth and proliferation; (2) delineate how toxins and taste/odor metabolite syntheses reflect molecular-, cellular-, and population-level responses to key environmental parameters; (3) assess current and future instrumentaland molecular-based identification and quantification technologies; and (4) coordinate an enhanced research response to harmful algal blooms. By bringing together researchers from divergent subject disciplines that would not typically meet, the symposium provided a forum for increasing communication among key laboratories and denoted clear avenues for expanded collaborative research.

Effects of N : P : Si ratios and zooplankton grazing on phytoplankton communities in the northern Adriatic Sea. III. Zooplankton populations and grazing

Abstract: Effects of N:P:Si ratios and zooplankton grazing on phytoplankton communities in the northern Adriatic Sea. III. Zooplankton populations and grazing