Term for a generative, that is, sexual reproduction with the parenthood of at least two different grape varieties, as is the case with the new breed of grape varieties is the case. One variety acts as the mother plant on which the berries ripen with the fertilized seeds, the other variety supplies the pollen as the father variety for pollinating the scars and fertilizing the maternal ovules (see also in detail under blossom and hermaphrodite flower ). Since the mid-1990s, the descent of grape varieties has become the worldwide standard DNA analysis to determine. It is also possible to crossing direction (who was the mother variety, who was the father variety). When specifying the crossing parents, the mother variety is always given first in the breeding lists. Four new varieties:
The fertilized ovules result in descendants that, according to Mendel's inheritance laws, each have half of the randomly recombined properties of both parents. In contrast to spontaneously occurring mutations, which lead to the development of slightly different grape clones, somatic chimeric and varieties of grape varieties, two parent varieties are always required for sexual reproduction, their crossing products, seedlings, each one individual genotype with new properties. These are often used for further crossings. Four classic grape varieties from natural crosses:
A new vine is usually through pollination created with pollen from another grape variety (although there are also rare crosses between different Clone same variety). It becomes a female flower bud Type A pollinated with Type B male pollen. There are three ways of crossing. In viticulture only interspecific and intergeneric crossings are considered hybrids referred to, although this is actually the case with intraspecific:
Crossing two grape varieties (cross-breeding) is one of the possible breeding methods in addition to selection breeding (cloning selection or cloning) and mutation breeding (artificial generation of mutants by mutagenic substances) - see below breeding, In contrast to this is the manipulative Genetic Engineering, with the desired properties such as resistance against fungal diseases or against frost by changing the genome. See also under Parent-offspring relationship and Vines systematics, A list of relevant keywords on the subject of grape varieties can be found at grapevine contain.
Images: Ursula Brühl, Doris Schneider, Julius Kühn Institute (JKI)