ROSE – The presence of Roses in vineyards, in particular at the ends of the rows, is a custom which has been in use since ancient times. Indeed, Roses have a very specific function: they act as a sentinels and are used like testers in order to verify the presence of Oidium. Since Roses is more sensitive than the vines, they are attacked earlier on by this fungus disease. Therefore, their job is to monitor the state of health of the rows, favouring also any preventive action by the wine maker should the harvest be threatened.
WATER: The grapevine needs about 345 litres of wate r to produce a single bottle of wine. Water, absorbed by the roots, climbs up through the xylematic vessels up to
the leaves, thereby hydrating all the tissues of the plant; when it arrives at the leaves it is almost entirely given back to the environment (97- 98%) in the form of water vapour, which exits the plants into the air via the stomas. It’s in the daytime, when temperatures are higher, that most of the water is lost through evaporation. It’s significant to underline that the stomas are found on the underside of the leaf; that is ,the part of the leaf not directly exposed to the sun: this mechanism, along with others, makes it possible for the cycle of water to be managed in a more efficient way throughout the plant.
REFRACTOMETRE – Thanks to the refractometre we can determine the sugar content of the must. The index of refraction of a liquid containing sugar is directly proportional to its concentration. How do you use the refractometre? Take this device and look towards the eyepiece in such a way as to clearly see the measuring scale which is inside. Open the prism and, after verifying that the outside is totally clean, place a few drops in one of the solutions that are inside the phials (one contains only water, one contains a solution of 10% sugar and the third contains a solution with 20% sugar).
Close the prism and look through the eyepiece towards a source of light. The dividing line which you see between the lighter field and the darker field gives an indication of the concentration of sugars that are in the liquid.
SLEEPING BUD – In the grapevine there is the so-called “ready” bud, which opens and forms a sprout in the same year in which the bud formed, but which doesn’t create grape bunches; then there is the sleeping bud which has a longer cycle because it opens, generating the sprout bearing fruit only the year following when the bud formed. In the sleeping bud, already in the month of August of the first year, you can find the primordial forms of the future grape bunches; looking at the image, you can clearly recognize a miniature grape bunch ready for next year!
This type of bud remains in its dormant phase and doesn’t bloom right away due to reasons connected to competition and the environment (low temperatures and shorter days). In Spring of the following year, as soon as the temperatures reach over 10°C and the days start getting longer (end of March-early April), the bud blooms and the small grape bunches can be seen.
STOMAS – On the underside of an average-size grape leaf, there are about three million tiny openings called stomas, which open and close based on the needs of the plant. Through these small openings, which are visible only through a microscope, carbon dioxide in the air is absorbed and is then brought throughout the tissues of the plant in order to carry out photosynthesis so that oxygen and water vapours are then expelled.