Microcystins (MC) and cylindrospermopsin (CYN) are potent toxins produced by diverse cyanobacterial genera found in waterbodies throughout the world. In the present study, and in order to achieve a better understanding of the fate of cyanobacterial toxins in the environment, we assessed the photodegradation of MC and CYN along the water column and by different radiation bands of the natural solar spectrum: photosynthetic active radiation (PAR), UV-A, and UV-B. Photodegradation of CYN seemed to be highly dependent on UV-A and was very low under natural conditions. This fact could be one of the reasons explaining the high extracellular CYN concentration found in diverse waterbodies. Microcystin photodegradation was higher, all three radiation bands (PAR, UV-A, and UV-B) being responsible for its degradation, although PAR and UV-A were more efficient because of their high natural irradiance. Modeling of MC photodegradation along the watercolumn was performed, using specific MC breakdown rates for the different radiation bands and including calculated attenuation coefficients for these bands. As a result, we suggest that rapid and efficient MC photodegradation may be expected in shallow systems or thin mixed layers.

We elucidate grapevine evolution and domestication histories with 3525 cultivated and wild accessions worldwide. In the Pleistocene, harsh climate drove the separation of wild grape ecotypes caused by continuous habitat fragmentation. Then, domestication occurred concurrently about 11,000 years ago in Western Asia and the Caucasus to yield table and wine grapevines. The Western Asia domesticates dispersed into Europe with early farmers, introgressed with ancient wild western ecotypes, and subsequently diversified along human migration trails into muscat and unique western wine grape ancestries by the late Neolithic. Analyses of domestication traits also reveal new insights into selection for berry palatability, hermaphroditism, muscat flavor, and berry skin color. These data demonstrate the role of the grapevines in the early inception of agriculture across Eurasia.

The summer phytoplankton population in the Arcos reservoir (Spain), an oligotrophic/mesotrophic waterbody, was dominated by the cyanobacterium Aphanizomenon ovalisporum, accompanied by Planktothrix cf. agardhii and smaller proportions of other cyanobacterial species. The bloom remained for approximately 1 month in the summer of 2004. The Arcos reservoir had moderate conductivity, up to 1756 mS cm À1, and relatively high nutrient concentrations. Planktonic biomass collected during the bloom period was found to be toxic by the Artemia salina bioassay. Analytical procedures based on high-performance liquid chromatography (HPLC) indicated the absence of microcystins and anatoxin-a but clearly demonstrated the presence of cylindrospermopsin (CYN), suggesting that CYN from Aphanizomenon ovalisporum was the compound responsible for the toxicity in the bioassay. Measurements indicate that up to 9.4 mg CYN l À1 were present in the sestonic fraction. This is the first report of high concentrations of this cyanotoxin in European waters and the first known instance of a massive bloom of the cyanobacterium Aphanizomenon ovalisporum in Spain.

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The occurrence and concentration of microcystins were analysed in sestonic samples from seven water reservoirs in the Madrid region (Spain) between July and November in two consecutive years (2002 and 2003). The data collected indicate that microcystins were present on several occasions in both years in all the reservoirs studied. The months of maximum risk for cyanotoxin occurrence were July, September and October, when Microcystis typically dominated the phytoplankton community. Four of the seven reservoirs exhibited conspicuous blooms, three of which were toxic. Of the samples in 2003, 45% and 70%, respectively, contained microcystins (Mc). In four of the reservoirs, microcystin concentrations were higher than the WHO recommended limit for drinking water (1 mg Mc l . From the data obtained we can conclude that M. aeruginosa is the main producer of microcystins in freshwaters from the Madrid region.