Effect of two water deficit regimes on the agronomic response of 12 grapevine varieties cultivated in a semi-arid climate

Recently, foliar treatments with mineral-based compounds have shown positive effects on grapevine production by protecting grape from thermal excesses and reducing the decoupling between technological and phenolic maturity caused by climate change. Unraveling the effect of mineral particle applications on grape-associated microbes is pivotal for successful wine processing, due to the influence of the microbiota on wine composition and stability. To our knowledge, this is the first work that comprehensively studied the effects of kaolin and chabasite-rich zeolitites treatments on grape-related microorganisms (by real-time PCR quantification of total fungi, Hanseniospora uvarum, Metschnikowia pulcherrima, plant-associated bacteria and lactic acid bacteria), the expression of genes related to the flavonoid biosynthesis (PAL1, CHS1, F3H2, DFR, LDOX, UFGT, MYBA1, GST4, FLS4 genes) and the berry composition (°Brix, pH, acidity and anthocyanin concentrations) in cv. Sangiovese during ripening in two growing seasons (2019 and 2020).

Bacterial antibiotic resistance is a major current health problem. Polyphenols have demonstrated antibacterial activity, and in this work we studied the effect of oenological polyphenols on the growth of intestinal multidrug-resistant strains of human and animal origin. Two Enterococcus faecium strains, resistant to vancomycin and other antibiotics, and four Escherichia coli strains, resistant to ampicillin and other antibiotics, were included in this study. All strains showed multidrug resistant phenotypes and genotypes to at least two antibiotic families.

Remote sensing technology captures spectral data beyond the visible range, making it useful for monitoring plant stress. Vis-NIR (Visible-Near Infrared) spectroscopy (400-1000 nm) is commonly used to indirectly assess plant status during drought. One example is the widespread use of normalized difference vegetation index (NDVI) that is strongly linked to green biomass. However, a knowledge gap exists regarding the applicability of this method to all the drought conditions and if it is a direct correlation to the water status of the plant.

The odors of wines are diverse, complex and dynamic and much research has been devoted to the understanding of their chemical bases. However, while the “basic” chemical part of the problem, namely the identity of the chemicals responsible for the different odor nuances, was satisfactorily solved years ago, there are some relevant questions precluding a clear understanding. These questions are related to the physicochemical interactions determining the effective volatilities of the odorants and, particularly, to the perceptual interactions between different odor molecules affecting in different ways to the final sensory outputs.

Grapevine cultivars are vegetatively propagated to preserve their varietal characteristics. However, spontaneous somatic variations that occur and are maintained during cycles of vegetative growth offer opportunities for the natural improvement of traditional grape cultivars. One advantageous trait for winegrowing is reduced bunch compactness, which decreases the susceptibility to pests and fungal diseases and favor an even berry ripening.