Term for the during the blossom self-pollination of a plant with its own pollen, which subsequently leads to self-fertilization (in practice, however, the two terms are often not actually used correctly as a synonym). The cultivated vine mostly has hermaphrodite, The male and female organs are in one flower bud united. This is largely due to the fact that cultivated vines mostly self-fertilization. The process within the hermaphrodite flower (autogamous) or between two flowers of the same appearance (later grape) is called self-fertilization in the narrower sense. Between blossoms of two parts of a vine, this is called self-fertilization in a broader sense (geitonogam).
A new variety with a fundamentally different genetic composition is most likely to emerge when it is not self-fertilization but one pollination by another variety. In this way, innumerable grape varieties have grown spontaneously in thousands of years when the grape seeds came into the soil and germinated. Today's varieties, however, only emerged through the selection of humans, who according to different criteria such as higher earnings or tastiness "best" vines and vegetatively propagated them. However, the genetic material of mother and father plants are also recombined if fertilization took place within two vines of the same variety. However, their genetic differences are rather small because the vines in the vineyard mostly Clones (1: 1 copies) vegetative propagation are.
For the look and taste of the grapes it is irrelevant by which father the fertilization takes place. They correspond externally and in terms of varietal Properties always 100% of the mother, no matter what paternal genes the berry seeds contain (see below blossom ). If self-fertilized grape seeds get into the soil and germinate there, arises from the seedling an inbred variety. However, self-occurrences occurring in nature rarely lead to a qualitative improvement, because mostly negative inbreeding effects (depression) appear, which are expressed in a lower vitality, a lower fruit set and an increased susceptibility to pathogens (pathogens). However, this is undesirable in viniculture, or it does not matter, since the grapes for pressing and their seeds are not intended for sowing. The multiplication of vines on a large scale does not take place on sexual, but rather vegetative Way instead.
Often such self-fertilized seeds do not germinate or they germinate, but the berry kernels of this new vine plant are sterile (virgin). This also depends on the variety; the seeds of Gouais Blanc z. B. are particularly capable of germinating (more than 100 varieties are derived from it). Even if you cross their descendants, they are still fertile. Many varieties result in depressed offspring. Only about 10% of the offspring have a positive gene combination. Nature protects itself against negative effects by the fact that as with the Wild vines male and female organs occur only separately on different plants ( dioecious ), or that self-fertilization is not possible due to self-sterility. In the breeding (Crossbreeding) one tries specifically to use the positive inbreeding effects by reinforcing positive traits. There may be two different ones Clones same grape variety crossed.
Graphics: taken from Bauer / Regner / Schildberger, viticulture,
ISBN: 978-3-70402284-4, Cadmos Verlag GmbH