Decline of rootstock-mediated physiological responses in Tempranillo grapevines by prolonged extreme conditions

In field conditions, grapevine roots are colonized by arbuscular mycorrhizal fungi (AMF). Little is known about the species composition of AMF communities associated to grapevine.

Grape pomace (GP) is a winemaking by-product particularly rich in (poly)phenols and dietary fiber, which are the main active compounds responsible for its health-promoting effects. GP-derived products have been proposed to manage cardiovascular risk factors, including endothelial dysfunction, inflammation, hypertension, hyperglycemia, and obesity. Studies on the potential impact of GP on gut health are much more recent. However, it is suggested that, to some extent, this activity of GP as a cardiometabolic health-promoting ingredient would begin in the gastrointestinal tract as GP components (i.e., (poly)phenols and fiber) undergo extensive catabolism, mainly by the action of the intestinal microbiota, that gives rise to low-molecular-weight bioactive compounds that can be absorbed and utilized by the body.

Diurnal changes in the leaves of field-grown grapevine (Vitis vinifera L.) cultivars Syrah and Tempranillo were followed over summer 2009 with respect to gas exchanges. Net photosynthetic rate (AN) of both cultivars rapidly increased in the morning, decreasing slowly until the late afternoon, when reached the lowest values.

Evidence for a specific effect of soil mineral composition on wine character is largely anecdotal. However, soil potassium supply to the vine must be properly balanced between deficiency and excess for good fruit quality.

Chitosan is a biopolymer industrially obtained from the deacetylation of chitin, the second most abundant polysaccharide on earth, after cellulose. It is extracted from various terrestrial and marine resources, including insects, grasshoppers, shrimps, crabs, lobsters, squids, and fungi. chitosan has a polycationic character due to the free amine groups along its chemical backbone, and depending on its deacetylation degree (DD) and molecular weight (MW), it shows variable properties that differ from those of other natural polysaccharides.