Metabolic and physiological changes in Prymnesium parvum when grown under, and grazing on prey of, variable nitrogen:phosphorus stoichiometry.

Mixotrophy is found in almost all classes of phytoplankton in a wide range of aquatic habitats ranging from oligotrophic to eutrophic marine and freshwater systems. Few studies have addressed how the nutritional status of the predator and/or the prey affects mixotrophic metabolism despite the realization that mixotrophy is important ecologically. Laboratory experiments were conducted to examine changes in growth rates and physiological states of the toxic haptophyte Prymnesium parvum when fed Rhodomonas salina of varying nutritional status.

Skeletonema marinoi (Bacillariophyceae) sensitivity to herbicides and effects of temperature increase on cellular responses to terbuthylazine exposure.

The North East area of Italy is an intensively farmed area, where the use of herbicides has increased dramatically during the last years. Some of the most detected herbicides are triazine compounds, such as: simazine (SIM), terbuthylazine (TBA), its degradation product desethyl-terbuthylazine (D-TBA) and other herbicides, such as metolachlor (MET). In this paper, the sensitivity of the diatom Skeletonema marinoi to the most detected herbicides (TBA, D-TBA, SIM and MET) was preliminarily studied.

Combined effects of the herbicide terbuthylazine and temperature on different flagellates from the Northern Adriatic Sea.

The triazinic herbicide terbuthylazine (TBA) is becoming an emergent contaminant in Italian rivers and in coastal and groundwater. A preliminary analysis of the sensitivity of marine flagellates to TBA was performed by monitoring the photosynthetic efficiency of nine species (belonging to the Dinophyceae or Raphidophyceae class) isolated from the Adriatic Sea. Different sensitivity levels for each flagellate were observed and the most sensitive microalgae, based on PSII inhibition, were: Gonyaulax spinifera>Fibrocapsa japonica>Lingulodinium polyedrum while the most resistant were two species belonging to the Prorocentrum genus.