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The Dune System of Don˜ana National Park (SW Spain) exhibit a mosaic of environmental characteristics, with different plant communities, all under the same Mediterranean climate, creating an interesting field laboratory for the study of plant responses to stressing conditions. Fourteen woody plant populations were selected, belonging to either xerophytic or hygrophytic plant communities on stabilised dunes, where topography causes differences in soil water availability. Plants were tagged and morphological and ecophysiological measurements were recorded in winter and summer of 1999. Seasonal differences in ecophysiological measurements together with morphological variables were used as plant traits to identify the main adaptive responses of the species. Cluster analysis of traits separated three groups of plant strategies: spiny legume species; sclerophyll, and semideciduous species. In addition, another two kind of strategies have been found in the semideciduous group of species, those withstanding water shortages, attaining very negative water potentials, low photochemical efficiency, and leaf proline accumulation in summer, as opposed to those tolerating water deficit, with moderate seasonal differences in water potential, proline content and photochemical efficiency. The results of this study indicate that legume species behave as a different functional group and drought-semideciduous species present different adaptive responses under the same environmental stress. Ecophysiological measurements must be used as plant traits to detect functional groups under Mediterranean climate.

Corema album is a dioecious shrub endemic of the Iberian Peninsula, growing in sandy coastal areas from the North of Galicia to Gibraltar in the South. Hermaphrodite individuals have been found in the southern populations of El Asperillo (Spain) and Vila Real de Santo Antonio (Portugal). In this paper, the role of hermaphroditic individuals in the driest populations of its biogeographical area is discussed and the tradeoff between reproduction and vegetative growth in the three sexual forms is presented. Asperillo site where hermaphrodite individuals were more abundant was selected for this current study. The proportion of hermaphrodite individuals was 1-4%, and male/female sex ratio ranged from 0.9 to 1.1. Hermaphrodite plants had a low number of hermaphrodite inflorescences, in relation to the number of staminate inflorescences. Their ripe fruits were smaller than those of female plants. The reproductive effort was three times higher in female than in male or hermaphrodite plants. The observed interannual oscillation in vegetative elongation was not related to annual rainfall. However, differences existed in growth timing among the three sexual forms, related to the timing of peak investment in reproduction. These results suggest the existence of trade-offs between investment in reproduction and vegetative growth. There were significant differences in leaf water potential among the three sexual forms early in summer, with males showing the less negative and hermaphrodite the most negative potential values. The demand of water for fruit production may explain these differences.

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The present study has been carried out in an organic winery established in 2003 in the Denomination of Origin ''Sierras de Málaga'' (Southern Spain) region during the 2007 vintage. The aim of this work was to ascertain the yeast microflora present in the winery and during the vinifications and to obtain a collection of autochthonous S. cerevisiae strains from this area. Yeast populations from three vats containing fermenting musts from different grape varieties were analysed. Two of them were inoculated with a natural ''pied de cuve'' while the third one was sown with a rehydrated commercial yeast strain. A total of 382 yeasts were isolated and identified, initially by restriction analysis of ribosomal DNA and further by sequencing of this region. Non-Saccharomyces yeasts were found in all three musts but they practically disappeared as the fermentations progressed. Analysis of mitochondrial DNA RFLP revealed 13 different restriction patterns of Saccharomyces cerevisiae strains, five of them similar to those of commercial strains used in the winery. Commercial strains were found even in vats inoculated with a ''pied de cuve'' generated by spontaneous fermentation of a must sample. The analysis of samples recovered from different winery surfaces and equipments demonstrated that nonSaccharomyces and both commercial and autochthonous Saccharomyces strains were part of the resident microflora in the winery. Biodiversity of autochthonous S. cerevisiae in fermentation vats was low but two of them were able to compete with the commercial ones and they were isolated even at the end of the fermentation.

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An ecological study of the yeasts present in a spontaneous and an inoculated fermentation in red wine was carried out in 2005 vintage in a winery located in the Denomination of Origin "Sierras de Málaga" (Málaga, southern of Spain). The winery operated by the first time with the 2003 vintage and since then, has used commercial yeast inocula to start alcoholic fermentation. Yeast isolates were identified by PCR-RFLP analysis of the 5.8S-ITS region from the ribosomal DNA and by mitochondrial DNA RFLP analysis. Except for non-Saccharomyces yeasts found in the fresh must before fermentation, all the isolates were found to be commercial Saccharomyces cerevisiae strains employed by the winery during the successive vintages; thus, no indigenous Saccharomyces yeasts were isolated during fermentation. The same four restriction patterns were found in non inoculated and inoculated vats, although with different frequencies. The use of commercial yeast starter in a new established winery seems to have prevented the development of a resident indigenous Saccharomyces flora.