Explore the vast range of titles available.

Background and Aims Precision viticulture encompasses a series of techniques from remote to proximal sensing for describing and exploiting within‐vineyard variability. Our aim was to assess how vigour mapping associated with detailed ground‐truthing can provide guidelines for more sustainable vineyard management. Methods and Results A satellite image taken with a 5 m‐pixel resolution on a mature, small‐sized (0.6 ha) cv. Barbera vineyard at full canopy made it possible to build a vigour map on the assessment of normalised difference vegetation index (NDVI) distinguishing low‐vigour (LV), medium‐vigour (MV) and high‐vigour (HV) areas of equal surface. Detailed single‐vine records for vegetative growth (shoot length, leaf area and pruning mass), yield components (bud fruitfulness, yield per vine and bunch and berry mass) and grape composition were recorded within each vigour class at harvest; leaf nutritional status and ripening curves were monitored for the same classes. While NDVI showed a close correlation to several vegetative, yield and grape composition parameters, LV vines exhibited excellent performance for remunerative yield (3.2 kg/vine, or a potential yield of 13.3 t/ha) and full ripening with maintenance of adequate TA. Both MV and HV showed excessive vigour and cropping leading towards incomplete ripening. Conclusions The combination of NDVI mapping and detailed ground‐truthing allows the identification of the vigour level for the greatest vineyard efficiency and the definition of an appropriate strategy either to exploit current variability through selective harvesting or to correct variability through variable rate application of nitrogen. Significance of the Study The NDVI mapping via low‐resolution satellite images associated with ground‐truthing appears to be a straightforward protocol to increase sustainable vineyard management.

One of the most dangerous fungal diseases in viticulture is downy mildew. Copper-based active ingredients have been used for a long time to protect vines against Plasmopara viticola and they have always maintained an important role in the defense of vines especially for organic production. On the other hand, copper accumulates in the soil causing toxicity with negative consequences on plants and soil fauna. For this reason, new formulations with lower copper content have been considered. In recent years, foliar fertilizers have been studied, in particular those based on phosphites that, along with the nutritional function, stimulate the production of phytoalexins. Those metabolites cause the induced systemic resistance and act directly in the break of cell membranes of pathogens. This study aims to investigate the efficacy against downy mildew of a commercial product based on phosphites and of a new copper- based foliar fertilizer, where copper is chelated with gluconic acid and aminoacids of plant origin. Based on present results, phosphites significantly reduced the infection, without anyway achieving the defense effectiveness of the copper-based treatment however they ensure a significant reduction of the doses of copper necessary to achieve adequate levels of vineyard protection.

Remote-Sensing (RS) is the most widely used technique for crop monitoring in precision viticulture systems. This paper considers the possibility of substituting RS information obtained by various proximal sensing technologies employed directly in vineyards in order to enable a simultaneous evaluation of canopy health and vigour status. To this aim, a mobile lab has been developed. It consists of (a) two GreenSeeker RT100 sensors, a commercial optical device calculating NDVI, and Red/NIR indices in real time; (b) three pairs of ultrasonic sensors to estimate canopy thickness; and (c) a DGPS receiver to geo-reference data collected while travelling in a vineyard. During the 2007–2008 campaign, tests were carried out in a commercial vineyard in order to evaluate the monitoring system performance regarding disease appearance, diffusion, and vegetative development variations due to the normal growing process of vines. Surveys with the mobile lab were conducted in two groups of rows, treated and untreated with agrochemicals, and compared to manual morphological and physiological observations that characterised the phytosanitary status of the canopy. Measurement repeatability was verified; both NDVI values and ultrasonic data showed high repeatability (with r  = 0.88 and r  = 0.85, respectively). Optical data were processed in order to obtain NDVI maps, which clearly showed differences in canopy vigour evolution in the two examined groups, with low vegetative vigour in areas infected by Plasmopara viticola , as confirmed by manual assessment. Maps of the percentage infection index (I%I) were produced according to pathological manual survey results. The comparison between I%I and NDVI maps qualitatively confirmed the real vine phytosanitary status. Ultrasonically measured canopy thickness (UCT) was calculated and compared to manually measured canopy thickness (MCT) ( r  = 0.78). UCT and NDVI values were compared in order to identify areas affected by disease among zones presenting critical vegetation conditions.

Background and Aims The increasing interest by the wine market in sparkling white wines challenges how the desired grape composition can be achieved under the pressure of global warming. The aim of the present study was to assess the viability of summer pruning as a tool to pilot ripening towards desired compositional patterns. Methods and Results Ortrugo was subjected to basal leaf removal applied either at pre‐flowering (ELR) or in lag‐phase (LLR) and to bunch thinning (BT; removal of 50% of crop at lag‐phase) in comparison with untreated control (C). Treatments induced large variation in bunch mass (30% less in ELR vs BT), yield per vine (37 and 21% less in BT and ELR vs C) and total soluble solids at harvest (BT scored 2.9°Brix higher than that of C). Conversely, given the same harvest date, all practices failed to maintain titratable acidity (TA) at the threshold of 6.5 g/L. Conclusions The data suggest that crop regulation achieved in the high yielding Ortrugo, through either BT or ELR, increases sugar accumulation rate so that concurrent optimal TA level (≅6.5 g/L) can be easily achieved by slightly anticipating harvest date. Under conditions of thermal or light stress, or weather conducive to bunch rot, preference should be given to ELR. Significance of the Study Suitable summer pruning techniques might be used as flexible and powerful tools to direct ripening towards the desired crop composition.

Digitonin-permeabilized PC12 and GT1-7 neural cells exhibited a cyclosporin A-sensitive decrease in mitochondrial membrane potential, increased volume, and release of the pro-apoptotic factor cytochrome c in the presence of Ca2+ and the mitochondrial permeability transition (MPT) inducers t-butyl hydroperoxide (t-bOOH) or phenylarsine oxide (PhAsO). Although the concentration of PhAsO required to induce the MPT was similar for Bcl-2 negative and Bcl-2 overexpressing transfected cells (Bcl-2(+)), the level of t-bOOH necessary for triggering the MPT was much higher for Bcl-2(+) cells. A higher concentration of t-bOOH was also necessary for promoting the oxidation of mitochondrial pyridine nucleotides in Bcl-2(+) cells. The sensitivity of Bcl-2(- ) cell mitochondria to t-bOOH but not PhAsO could be overcome by the use of conditions that protect the pyridine nucleotides against oxidation. We conclude that the increased ability of Bcl-2(+) cells to maintain mitochondrial pyridine nucleotides in a reduced redox state is a sufficient explanation for their resistance to MPT under conditions of oxidative stress induced by Ca2+ plus t-bOOH.

Objective: We recently described that hypertriglyceridemic apolipoprotein (apo) CIII transgenic mice show increased whole body metabolic rate. In this study, we used these apo CIII-expressing mice, combined or not with the expression of the natural promoter-driven CETP gene, to test the hypothesis that both proteins modulate diet-induced obesity. Measurements and results: Mice expressing apo CIII, CIII/CETP, CETP and nontransgenic (NonTg) mice were maintained on a high-fat diet (14% fat by weight) during 20 weeks after weaning. At the end of this period, all groups exhibited the expected lipemic phenotype. Fasting glucose levels were neither affected by the high-fat diet nor by the distinct genotypes. However, apo CIII mice showed significantly higher glycemia (approximately 35%) and lower insulin levels (approximately 45%) in the fed state, compared with the NonTg mice. The apo CIII mice presented significantly increased body weight, lipid content of the carcass (approximately 25%), visceral adipose tissue mass (about twofold) and adipocyte size (approximately 25%) compared with the CETP and NonTg mice. The CETP expression in the apo CIII background normalized the subcutaneous adipose depot and visceral adipocyte size to the levels of NonTg mice. Plasma leptin levels were lower in CETP groups (25-50%) and higher in the apo CIII mice. Similar core body temperature in all groups and similar liver mitochondrial resting respiration rates in CIII and NonTg mice indicate no differences in basal energy expenditure rates among these mice fed a high-fat diet. Conclusion: The elevation of plasma apo CIII levels aggravates diet-induced obesity and the expression of physiological levels of circulating CETP reverses this adipogenic effect, indicating a novel role for CETP in modulating adiposity.

Tomato (Lycopersicon esculentum) mitochondria contain both alternative oxidase (AOX) and uncoupling protein as energy-dissipating systems that can decrease the efficiency of oxidative phosphorylation. We followed the cyanide (CN)-resistant, ATP-synthesis-sustained, and uncoupling-protein-sustained respiration of isolated mitochondria, as well as the immunologically detectable levels of uncoupling protein and AOX, during tomato fruit ripening from the mature green stage to the red stage. The AOX protein level and CN-resistant respiration of isolated mitochondria decreased with ripening from the green to the red stage. The ATP-synthesis-sustained respiration followed the same behavior. In contrast, the level of uncoupling protein and the total uncoupling-protein-sustained respiration of isolated mitochondria decreased from only the yellow stage on. We observed an acute inhibition of the CN-resistant respiration by linoleic acid in the micromolar range. These results suggest that the two energy-dissipating systems could have different roles during the ripening process.

One hypothesis for the etiology of cell damage arising from iron overload is that its excess selectively affects mitochondria. Here we tested the effects of acute iron overload on liver mitochondria isolated from rats subjected to a single dose of i.p. 500 mg/kg iron-dextran. The treatment increased the levels of iron in mitochondria (from 21 ± 4 to 130 ± 7 nmol/mg protein) and caused both lipid peroxidation and glutathione oxidation. The mitochondria of iron-treated rats showed lower respiratory control ratio in association with higher resting respiration. The mitochondrial uncoupling elicited by iron-treatment did not affect the phosphorylation efficiency or the ATP levels, suggesting that uncoupling is a mitochondrial protective mechanism against acute iron overload. Therefore, the reactive oxygen species (ROS)/H⁺ leak couple, functioning as a mitochondrial redox homeostatic mechanism could play a protective role in the acutely iron-loaded mitochondria.

Incubation of T. cruzi epimastigotes with the lectin Cramoll 1,4 in Ca 2+ containing medium led to agglutination and inhibition of cell proliferation. The lectin (50 µg/ml) induced plasma membrane permeabilization followed by Ca 2+ influx and mitochondrial Ca 2+ accumulation, a result that resembles the classical effect of digitonin. Cramoll 1,4 stimulated (five-fold) mitochondrial reactive oxygen species (ROS) production, significantly decreased the electrical mitochondrial membrane potential (ΔΨ m ) and impaired ADP phosphorylation. The rate of uncoupled respiration in epimastigotes was not affected by Cramoll 1,4 plus Ca 2+ treatment, but oligomycin-induced resting respiration was 65% higher in treated cells than in controls. Experiments using T. cruzi mitochondrial fractions showed that, in contrast to digitonin, the lectin significantly decreased ΔΨ m by a mechanism sensitive to EGTA. In agreement with the results showing plasma membrane permeabilization and impairment of oxidative phosphorylation by the lectin, fluorescence microscopy experiments using propidium iodide revealed that Cramoll 1,4 induced epimastigotes death by necrosis.

The skeletal muscle mitochondria contain two isoforms of uncoupling protein, UCP2 and mainly UCP3, which had been shown to be activated by free fatty acids and inhibited by purine nucleotides in reconstituted systems. On the contrary in isolated mitochondria, the protonophoretic action of muscle UCPs had failed to be demonstrated in the absence of superoxide production. We showed here for the first time that muscle UCPs were activated in state 3 respiration by linoleic acid and dissipated energy from oxidative phosphorylation by decreasing the ADP/O ratio. The efficiency of UCPs in mitochondrial uncoupling increased when the state 3 respiratory rate decreased. The inhibition of the linoleic acid-induced uncoupling by a purine nucleotide (GTP), was not observed in state 4 respiration, in uninhibited state 3 respiration, as well as in state 3 respiration inhibited by complex III inhibitors. On the contrary, the progressive inhibition of state 3 respiration by n -butyl malonate, which inhibits the uptake of succinate, led to a full inhibitory effect of GTP. Therefore, as the inhibitory effect of GTP was observed only when the reduced state of coenzyme Q was decreased, we propose that the coenzyme Q redox state could be a metabolic sensor that modulates the purine nucleotide inhibition of FFA-activated UCPs in muscle mitochondria.