Name (also bud) for the youthful state of a new sprout or Triebes, At the Rebstock the eye is in the leaf axils to the Nodien (Nodules) of annual shoots (hence armpit bud or axillary bud). The winter eye consists of lignified bracts, which are layered in several layers and wrap around the primary, already pre-differentiated plants of the new shoot. Already recognizable in miniature form are the drive segments of the stem axis with the laterally angled plants for leaves (Leaves), tendrils (Fasteners) and inflorescences (Gescheine). The cavities in the bud are filled with fine wool hair, so that the instinctual system during the Hibernation until the expulsion in the spring from injuries, frost and wetness is protected. In the place of the Nodien is the diaphragm (Wood bridge).
In addition to the main eye (attachment for main shoot) each winter bud also contains two laterally at the base of the bud floor sitting eyes (secondary eyes). These are also already pre-differentiated, but simpler in design and serve as emergency buds in an emergency. As a rule, they only drive out when the main eye or the young impulse resulting from it, is affected by external circumstances, such as frost. game browsing or insect feeding was destroyed or in the spring for example by mite infestation is inhibited in growth. Then the hormonal dominance of the main shoot is broken, the expulsion of the eyes is no longer suppressed, and it can form one to two shorter side shoots, which may be infertile.
After this expulsion During the growth period of the one-year-old fruit shoot new axillary buds form in the leaf axils after differentiation of the young leaves. These buds represent a Doppelknospen plant (double eyes), which consists of a summer eye and the winter eye. The summer eyes are the plant for those growing from the leaf axils of the fruit trusses in the summer epicormic shoot, Their budding is hormonally controlled and variety specific, but they may not have to drive out of the summer eyes. Until summer, the summer eye is larger than the winter eye. If it does not grow into a stinghorn, it usually stunted, while the second bud plant (winter eye) swells in the Blattachsel and ripens to the vigorous winter bud. This no longer drives, but survives due to the insulating wool under the lignified bud scales optimally protected the winter.
With rising temperatures, the winter bud breaks in late spring expulsion in order to grow into a new long shoot, in the leaf axils again double bud plants with summer and winter eye arise. Summer and winter buds are spatially closely associated in the Blattachsel, but they are not equal to each other, but below (unequal). For the winter bud is anatomically the axillary bud of the only dandruff leaf of the Geizknospe, so that it represents a base-close bud formation of a potential Geiztriebs. In mild winters, a stunted summer bud can survive for a year, so that next spring at the base of the fruit shoot can still develop a contribution from it. In winter pruning the vine is cut back to the desired number of winter eyes). A good unit of measurement is that Timber weight one leaves 30 eyes per kilogram of cut wood.
In the spring, fresh fruit shoots emerge from the eyes, which have been left standing for one year, and again bear leaves, flowers, buds and tendrils. Without annual pruning, the annual buds of the shoots would develop new lateral levels each year with new shoots and buds. The vine would continue to expand in terms of area, a rational management would not be possible (the record holds one Versoaln Vine in South Tyrol). Because this is too uncontrollably higher earnings and thus inevitably lead to loss of quality in wine, the already mentioned pruning takes place.
Basal eyes are called the axillary buds at the base of annual shoots. This area is already formed shortly after bud breakout. The internodes are still very compressed, so that several nodes with alternating axillary buds closely over each other. These buds usually only drive out when pruning spigot (very short shoots) is cut back. Depending on the grape variety, the basal lobes are reduced in their fertility. There are even grape varieties like Luglienga Bianca (Seidentra grape), which is quite barren on the first five basal lobes, leaving a head cut on cones would lead to total failure of the crop.
As a sleeping eye becomes one adventitious referred to, which is formed at the trunk or root of the vine. In contrast to the axillary buds, these have not been preformed the year before, but are only newly induced (triggered) somewhere in the case of growth disorders or injuries to the vine. The tribal side shoots are called water shoots, which serve as a reserve for emergencies. They are very vigorous and infertile in the first year, as they are programmed for rapid growth to function as the caring or already dead mainstay of the vine to replace as quickly as possible. See a list of keyword relevant keywords below grapevine,
Graphics: taken from Bauer / Regner / Schildberger, viticulture, ISBN: 978-3-70402284-4, Cadmos Verlag GmbH