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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.

Anthocyanins are responsible for grape color, an important quality factor for market acceptance. The relative proportion of cyanidin-based (cyanidin- and peonidin-derivatives) and delphinidin-based (delphinidin-, malvidin- and petunidinderivatives) anthocyanins largely determines the color variation among red/purple/blue colored grape varieties. Anthocyanin biosynthesis is under complex regulation by nutrients, hormones, and environmental cues sensed by the berry. However, the physiological mechanisms underlying these regulations are poorly understood. A dynamic model was developed to simulate the developmental anthocyanin composition in two genotypes and different carbon and nitrogen conditions. This model describes the flux partitioning by basic chemical reaction rules with total anthocyanin as input and reaction rates as parameters. Data were gathered from two experiments, which studied the developmental changes in anthocyanin composition. The model was calibrated for two cultivars under a given growth condition and then validated by applying the model to other conditions for the same cultivar. The model can successfully simulate all the observed modifications in anthocyanin composition throughout berry ripening. This provides an alternative way of phenotyping by dissecting a complicated trait (anthocyanin content and composition) into developmentally stable traits (model parameters).

Grape berry composition mainly consists of primary and secondary metabolites. Both are sensitive to environment and viticultural management. As a consequence, climate change can affect berry composition and modify wine quality and typicity. Leaf removal techniques can impact berry composition by modulating the source-to-sink balance and, in turn, may mitigate some undesired effects due to climate change. The present study investigated the balance between technological maturity parameters such as sugars and organic acids, and phenolic maturity parameters such as anthocyanins in response to source-sink modulation. Sugar, organic acid, and anthocyanin profiles were compared under two contrasting carbon supply levels in berries of cv. Cabernet Sauvignon and Sangiovese collected at 9 and 14 developmental stages respectively. In addition, whole-canopy net carbon exchange rate was monitored for Sangiovese vines and a mathematic model was used to calculate the balance between carbon fixation and berry sugar accumulation. Carbon limitation affected neither berry size nor the concentration of organic acids at harvest. However, it significantly reduced the accumulation of sugars and total anthocyanins in both cultivars. Most interestingly, carbon limitation decreased total anthocyanin concentration by 84.3% as compared to the non source-limited control, whereas it decreased sugar concentration only by 27.1%. This suggests that carbon limitation led to a strong imbalance between sugars and anthocyanins. Moreover, carbon limitation affected anthocyanin profiles in a cultivar dependent manner. Mathematical analysis of carbon-balance indicated that berries used a higher proportion of fixed carbon for sugar accumulation under carbon limitation (76.9%) than under carbon sufficiency (48%). Thus, under carbon limitation, the grape berry can manage the metabolic fate of carbon in such a way that sugar accumulation is maintained at the expense of secondary metabolites.

Fourteen mineral elements are considered essential for higher plant growth; these elements include 6 macronutrients (N, P, K, Ca, Mg, S) and 8 trace elements (Fe, Mn, Zn, Cu, Cl, B, Mo, Ni). The physiological role of each element is described, as well as the deficiency symptoms and the methods to prevent or cure the nutritional disorders. Leaf blade and/or petiole chemical analysis is an important tool to assess the nutritional status of the plant and the methodology to perform the leaf sampling is described as well as the optimum concentrations of each element. The effect of the grape variety, rootstock and environmental conditions on mineral nutrition is described, as well as the amount of element uptake in the vineyard, which is crucial for fertilizer recommendation.

Aquaporins (AQPs) are ubiquitous membrane proteins whose identification, pioneered by Peter Agre's team in the early nineties, provided a molecular basis for transmembrane water transport, which was previously thought to occur only by free diffusion. AQPs are members of the Major Intrinsic Protein (MIP) family and often referred to as water channels. In mammals and plants they are present in almost all organs and tissues and their function is mostly associated to water molecule movement. However, recent studies have pointed out a wider range of substrates for these proteins as well as complex regulation levels and pathways. Although their relative abundance in plants and mammals makes it difficult to investigate the role of a particular AQP, the use of knock-out and mutagenesis techniques is now bringing important clues regarding the direct implication of specific AQPs in animal pathologies or plant deficiencies. The present paper gives an overview about AQP structure, function and regulation in a broad range of living organisms. Emphasis will be given on plant AQPs where the high number and diversity of these transport proteins, together with some emerging aspects of their functionalities, make them behave more like multifunctional, highly adapted channels rather than simple water pores. (c) 2009 Elsevier B.V. All rights reserved.