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Gina is a grapevine variety heterozygous for the mutant Gibberellic Acid Insensitive
(GAI) allele that confers dwarfness and continuous flowering. Gina vines are dwarf, with
internodes less than one-third the length of related non-dwarf plants. Gina vines
preferentially produce inflorescences in place of tendrils and consequently the vines are
continuously flowering. When cultivated in a greenhouse, Gina vines flower throughout
the year. Gina vines produce the pistillate flower type, with non-functional male flower
parts. The pistillate flowers of Gina vines are fertile and develop into seeded grapes
when cross pollinated. The pistillate flowers of Gina make the development of new
populations of dwarf vines very easy, because hybridization can be accomplished without
the need for emasculation. Gina vines can be grown to flowering in a 750 ml pot. In
comparison to the Pixie grape variety, Gina vines grow more quickly, although the
internodes are still very short and Gina vines are considered true dwarf vines (as are
Pixie grapevines). Gina vines are easier to cultivate in the greenhouse than Pixie
because of faster growth and Gina vines are more resistant to common greenhouse pests and
diseases than are Pixie vines.
The Gina grapevine variety will be useful for the development of new populations of GAI
dwarf grapevines for genetics and breeding research. Grapevine pollen can be applied to
Gina grapevine flowers on vines growing in a greenhouse and the resulting population
should be expected to segregate 1:1 dwarf:non-dwarf grapevines. The dwarf seedlings of
Gina would be expected to begin flowering in 90 to 100 days, with mature fruit 90 – 120
days later. Thus, Gina enables rapid development of GAI dwarf grapevine populations that
flower and fruit very rapidly and with small space requirement for genetics and breeding
research. Because Gina vines are pistillate flowered, no emasculation is needed for the
production of hybrid seeds, which makes using Gina as a parent in population development
very simple.
Gina grapevine originated from a cross of two non-patented grapevine varieties. The seed
parent is the rootstock 187G and the pollen parent is the dwarf grapevine Pixie. Both
the rootstock 187G seed parent and the dwarf grapevine Pixie pollen parent are free from
intellectual property restrictions and encumbrances. No proprietary information or
inventions are needed to fully utilize the Gina grapevine. Gina grapevine was tested by USDA ARS with the selection number PC08124-1.
Gina is germplasm for genetics, genomics, breeding, pathology, physiology, and other grapevine research. Crosses with Gina are expected to segregate for the semi-dominant dwarfing character that Gina inherited from Pixie. The space required per experimental grapevine is greatly reduced and Gina and other dwarf grapevines can be grown in the greenhouse to maturity without the need to plant them in a vineyard. Since the vines can be grown in the greenhouse to maturity, research is accelerated as it may be conducted year round. The continuous flowering habit of Gina provides researchers with the opportunity to study flowers and berries at all stages of development throughout the year. |
