Berry size variability in Vitis vinifera L.

In order to study the mechanisms of berry growth in Vitis vinifera L. we analysed cell division and pericarp enlargement of 6 genotypes showing high variability in berry size (range: 49-90 %. Both, cell number and cell volume were involved in the small-sized berries of the flb mutant producing wild-type-like berries. The differences of berry size observed in other small-sized clones were only due to cell expansion. The data suggest that the variability of berry size in V. vinifera cultivars predominantly results from modification of cell enlargement. Conversely, in wild-type-like berries, the variability of berry size could result from both, cell division and cell enlargement.

Berry development of grapevines: Relations between the growth of berries and their DNA content indicate cell multiplication and enlargement

DNA of berries (cv. Shiraz) was extracted and quantified to determine, indirectly, the rate of cell division and enlargement in the grape pericarp. The increase of total DNA in the pericarp begins at anthesis in the ovary of grapevine flowers (day 0, 100 % of flowers at full bloom). This increase in DNA continues during the herbaceous growth period until 35 d after anthesis (day 35, 19 d before the onset of veraison). Total DNA per berry pericarp does not increase linearly during this growth period since 75 % of the DNA has already accumulated before day 20. We determined a cell enlargement index (CEI), to estimate the mean cellular volume. The pericarp cell size increases 16-fold during the whole growth of berries. Volume increase is nearly linear from berry set to the beginning of veraison and thereafter until maturity. The importance of determination of cell division and enlargement of berry pericarp based on the DNA content and its possible application in studies on the influence of environmental factors on berry growth is discussed

Transcription of a β-1,3-glucanase gene in grape berries in a late developmental period, or earlier after wounding treatments

The hydrolytic enzymes β-1,3-glucanases (EC3.2.1.39) an known to be involved in plant defense reactions against pathogens and in developmental events. We have obtained two partial cDNA clones, corresponding to Vitis vinifera β-1,3-glucanase gene sequences (VvGlu1/7 and VvGlu26). The expression of VvGlu1/7 was studied in grape berries at different developmental stages and in wounded berries with or without salicylic acid elicitation. No constitutive expression was observed in young berries, whereas the induction of VvGlu1/7 transcription was detected during fruit ripening. By contrast, synthesis of mRNA coding for this isoform was generated in the first stage of rapid berry growth in response to wounding treatments with and without salicylic acid

First observations of the microvine development under 100 % LED (light emitting diodes) illumination

In order to reduce energy waste for artificial lights and subsequent air conditioning in plant growth chambers, the aim of this preliminary study was to evaluate the feasibility of growing the microvine under 100 % of LED illumination. Plant growth under two different LED lights was compared amongst each other and with plants maintained in greenhouse conditions. Regarding the impact on the reproductive and vegetative systems, the study showed that LED light is suitable to grow microvines in confined environments. Plants exposed to LED light exhibited similar leaf emergence rate but reduced vegetative and reproductive organ size compared to plants grown in the greenhouse. Photosynthesis for plants exposed to LED light was higher than what is usually observed on grapevine under natural conditions.

The Comparability of Men Who Have Sex With Men Recruited From Venue-Time-Space Sampling and Facebook: A Cohort Study

Background: Recruiting valid samples of men who have sex with men (MSM) is a key component of the US human immunodeficiency virus (HIV) surveillance and of research studies seeking to improve HIV prevention for MSM. Social media, such as Facebook, may present an opportunity to reach broad samples of MSM, but the extent to which those samples are comparable with men recruited from venue-based, time-space sampling (VBTS) is unknown. Objective: The objective of this study was to assess the comparability of MSM recruited via VBTS and Facebook. Methods: HIV-negative and HIV-positive black and white MSM were recruited from June 2010 to December 2012 using VBTS and Facebook in Atlanta, GA. We compared the self-reported venue attendance, demographic characteristics, sexual and risk behaviors, history of HIV-testing, and HIV and sexually transmitted infection (STI) prevalence between Facebook- and VTBS-recruited MSM overall and by race. Multivariate logistic and negative binomial models estimated age/race adjusted ratios. The Kaplan-Meier method was used to assess 24-month retention. Results: We recruited 803 MSM, of whom 110 (34/110, 30.9% black MSM, 76/110, 69.1% white MSM) were recruited via Facebook and 693 (420/693, 60.6% black MSM, 273/693, 39.4% white MSM) were recruited through VTBS. Facebook recruits had high rates of venue attendance in the previous month (26/34, 77% among black and 71/76, 93% among white MSM; between-race P=.01). MSM recruited on Facebook were generally older, with significant age differences among black MSM (P=.02), but not white MSM (P=.14). … See full text for complete abstract

Ethanol application at veraison decreases acidity in Cabernet Sauvignon grapes

Research NoteSpraying ethanol (5 % v/v in water) onto grape clusters at mid-veraison led to a 30 % drop in the malic acid concentration at harvest. As a consequence, titratable acidity also dropped by 10 %. The concentration of tartaric acid did not change significantly. The mode of action of ethanol on malic acid metabolism is discussed.

Dietary intake, lung function and airway inflammation in Mexico City school children exposed to air pollutants

<p>Abstract</p> <p>Introduction</p> <p>Air pollutant exposure has been associated with an increase in inflammatory markers and a decline in lung function in asthmatic children. Several studies suggest that dietary intake of fruits and vegetables might modify the adverse effect of air pollutants.</p> <p>Methods</p> <p>A total of 158 asthmatic children recruited at the Children's Hospital of Mexico and 50 non-asthmatic children were followed for 22 weeks. Pulmonary function was measured and nasal lavage collected and analyzed every 2 weeks. Dietary intake was evaluated using a 108-item food frequency questionnaire and a fruit and vegetable index (FVI) and a Mediterranean diet index (MDI) were constructed. The impact of these indices on lung function and interleukin-8 (IL-8) and their interaction with air pollutants were determined using mixed regression models with random intercept and random slope.</p> <p>Results</p> <p>FVI was inversely related to IL-8 levels in nasal lavage (p < 0.02) with a significant inverse trend (test for trend p < 0.001), MDI was positively related to lung function (p < 0.05), and children in the highest category of MDI had a higher FEV₁(test for trend p < 0.12) and FVC (test for trend p < 0.06) than children in the lowest category. A significant interaction was observed between FVI and ozone for FEV₁and FVC as was with MDI and ozone for FVC. No effect of diet was observed among healthy children.</p> <p>Conclusion</p> <p>Our results suggest that fruit and vegetable intake and close adherence to the Mediterranean diet have a beneficial effect on inflammatory response and lung function in asthmatic children living in Mexico City.</p