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Metabolic pathways leading to parameters involved in technological and phenolic maturities of berry are influenced by environmental factors. In this study we perform a detailed characterization of the soil-plant water status to determine its influence on the technological and polyphenolic ripening kinetics of berries, research was conducted on a ten-year-old Vitis vinifera cv. Aglianico vines located in a hilly landscape of South Italy (Avellino). Vines distributed over a slope gradient (over 100 m) differ strongly in their water status due to different soil hydrological behaviour. In two non irrigated plots located upper-slope (U) and lower-slope (L) position soil water variables (through TDR probes and tensiometers), crop development (biometric and physiological parameters) crop physiological measurement (leaf gas exchange, chlorophyll-a fluorescence, leaf water potential, chlorophyll content, LAI) and climate variables (Temperature, radiation, rainfall, wind) were monitored. Afterwards, a physically-based simulation model (SWAP) was calibrated and applied to estimate crop water stress index.. U plot resulted higher in water stress index and, as a consequence, the weight of berries obtained from this plot was reduced during ripening. Water deficit accelerated sugar accumulation and titrable acidity breakdown. Berries obtained from U vines showed also higher concentration of anthocyanins, total phenolics, tannins and vanilline reactive flavans in berry skins. Although at the beginning of berry maturation an higher content of total phenolics and tannins were extracted from seeds of U berries, in lasts data of sampling (from 21 to 24°Brix) no differences were detected. A higher content of ethanol, total phenolics, anthocyanins, tannins and vanilline reactive flavans was observed for wines elaborated after winemaking of grapes harvested on U plot. Wines produced from grapes of stressed vineyards were also preferred in tasting trials.

Petunia is an excellent model system, especially for genetic, physiological and molecular studies. Thus far, however, genome-wide expression analysis has been applied rarely because of the lack of sequence information. We applied next-generation sequencing to generate, through de novo read assembly, a large catalogue of transcripts for Petunia axillaris and Petunia inflata. On the basis of both transcriptomes, comprehensive microarray chips for gene expression analysis were established and used for the analysis of global- and organ-specific gene expression in Petunia axillaris and Petunia inflata and to explore the molecular basis of the seed coat defects in a Petunia hybrida mutant, anthocyanin 11 (an11), lacking a WD40-repeat (WDR) transcription regulator. Among the transcripts differentially expressed in an11 seeds compared with wild type, many expected targets of AN11 were found but also several interesting new candidates that might play a role in morphogenesis of the seed coat. Our results validate the combination of next-generation sequencing with microarray analyses strategies to identify the transcriptome of two petunia species without previous knowledge of their genome, and to develop comprehensive chips as useful tools for the analysis of gene expression in P. axillaris, P. inflata and P. hybrida. © 2011 Blackwell Publishing Ltd.

When experiencing water deficit, glycophyte plants undergo physiological and biochemical changes aimed at limiting cellular damages and rescuing a new cellular homeostasis. Discriminate irreversible cell injury from adaptive rearrangements to water stress, is quite critical since only the latter plant response is compatible with active growth and development sustaining, ultimately, plant yield. An up-dated view of the molecular basis of cellular response to drought stress and of key functions activated able to protect cellular processes is summarized in the paper. It also reported a functional approach developed to identify genes with a crucial role in the adaptation to water deficit based on the systematic comparison of potato cell populations exposed abruptly or gradually to PEG-induced low water potential. Gradually adapted cells were characterized by distinctive metabolic adaptations (proline accumulation, changes in membrane lipid composition, de novo synthesis, etc) which enable them to grow actively at non-permissive water stress conditions. Differential gene expression in response to shock or gradually increasing water deficit was monitored by microarray technology, using the 1K TIGR potato cDNA array. More than 100 genes belonging to different functional categories were up-regulated in response to stress conditions. However, only a few induced genes were common to both cell populations, confirming that different gene networks mediate shock or long-term response to water deficit.