This invention is a new and distinct grapevine variety denominated ‘IFG Thirty-nine’. The new grapevine is characterized by producing medium size narrow finger shaped yellow-green berries having medium firm texture with a muscat flavor and which ripen in mid-season. Berries are borne on medium size clusters which are naturally loose and do not require gibberellin applications to thin clusters.

Latin name of the genus and species claimed:Vitis interspecifichybrid.

BACKGROUND OF THE INVENTION

The new and distinct Grapevine plant described and claimed herein originated from a hand pollinated cross of ‘IFG 04150-020-228’ (unpatented), aVitis viniferaselection from the IFG breeding program, and ‘IFG Twenty-nine’ (U.S. Plant Pat. No. 29,651) hybridized in May 2010. The present variety of grapevine was selected as a single plant in August 2013 and was first asexually propagated by hardwood cuttings in December 2013 near Delano, Kern County, Calif. These resulting cuttings produced second generation plants that were planted during April 2014 near Delano, Kern County, Calif. and were observed for 4 years and found to reproduce true-to-type.

BRIEF SUMMARY OF THE INVENTION

The new grapevine ‘IFG Thirty-nine’ is characterized by producing medium size narrow finger shaped yellow-green berries having medium firm texture with a muscat flavor and which ripen in mid-season. Berries are borne on medium size clusters which are naturally loose and do not require gibberellin applications to thin clusters. Berry size can be increased by applying gibberellic acid. Berries store well and can be maintained in good condition for up to 8 weeks in cold storage. Clusters may occasionally exhibit some pink berries when exposed to high light intensity and stress. To the inventor's knowledge, the known variety to which the new grapevine variety is most similar is the Centennial Seedless variety (Table grape; U.S. Plant Pat. No. 4,784). ‘IFG Thirty-nine’ differs from ‘Centennial Seedless’ by having smaller berry size, firmer berries, with a narrower, more tapered finger shaped, lighter yellow-green skin color, strong muscat flavor and better storage ability.

‘IFG Thirty-nine’ differs from its maternal parent the ‘IFG 04150-020-228’ (unpatented seedling selection in the IFG breeding program) by having a narrower cylindrical to fingered shape berry shape and having a smaller berry size and more tapered tip. ‘IFG Thirty-nine’ is like its paternal parent, ‘IFG Twenty-nine’ by producing very elongated narrow pointed yellow-green berries. ‘IFG Thirty-nine’ differs from its paternal parent, ‘IFG Twenty-nine’ by having large soft seed traces and possessing a strong muscat flavor as opposed to the slightly larger diameter neutral flavored grapes of ‘IFG Twenty-nine’. ‘IFG Thirty-nine’ exhibits better storage ability and less skin browning compared to ‘IFG Twenty-nine’.

DETAILED BOTANICAL DESCRIPTION OF THE INVENTION

Throughout this specification, color names beginning with a small letter signify that the name of that color, as used in common speech, is aptly descriptive. Color names beginning with a capital letter designate values based upon R.H.S. Colour Chart, published in 2015 by The Royal Horticultural Society, London, England.

Throughout this specification, subjective description values conform to those set forth by the UPOV International Union for the Protection of New Varieties of Plants publication ‘GrapevineVitisL. Guidelines’.

The descriptive matter which follows pertains to 4-year-old plants of ‘IFG Thirty-nine’ plants grown in the vicinity of Delano, Kern County, Calif. during 2017 and 2018 and is believed to apply to plants of the variety grown under similar conditions of soil and climate elsewhere:

SHOOTS

Young shoot:Form of tip.—Wide open.Distribution of anthocyanin coloration of tip.—Absent.Intensity of anthocyanin coloration of tip.—Absent.Density of prostrate hairs on tip.—Dense.Density of erect hairs on tip.—Very sparse.Color.—Yellow-green: 144B.Woody shoot (mature canes):Internode length.—Long: About 14.3 cm.Width at node.—About 1.4 cm.Cross section.—Circular.Surface.—Striate.Main color.—The following colors were observed: Greyed-orange: 165B and 165C and 176A.Density of erect hairs on nodes.—None.Density of erect hairs on internodes.—None or very sparse.Axillary shoot length at full bloom.—Weak to medium.Flowering shoot:Vigor during flowering.—Medium.Attitude during flowering on shoots not tied.—Semi-drooping.Color.—Dorsal side of internodes — Yellow-green: 144A, with Red-purple stripes: 59A.Color.—Ventral side of internodes — Yellow-green: 144A.Color.—Dorsal side of nodes — Yellow-green: 144A, with Red-purple stripes: 59A.Color.—Ventral side of nodes — Yellow-green: 144A.Density of prostrate hairs on nodes.—Very sparse.Density of erect hairs on nodes.—None.Density of prostrate hairs on internodes.—Sparse.Density of erect hairs on internodes.—None.Anthocyanin coloration of buds.—Absent.Tendrils:Distribution on the shoot(at full flowering).—Discontinuous.Length of tendril.—Long: About 22.9 cm.Thickness of tendril2cm from base.—About 1.8 mm.Color.—Yellow-green: N144A.Form.—Bifurcated and trifurcated.Number of consecutive tendrils.—2.

LEAVES

Young leaves:Color of upper surface of first four distal unfolded leaves.—Yellow-green: 144A.Color of lower surface of young leaves.—Yellow-green: 146B.Average intensity of anthocyanin coloration of six distal leaves prior to flowering.—Absent.Density of prostrate hairs between veins(lower surface).—Medium to dense.Density of prostrate hairs on veins(lower surface).—Medium.Density of erect hairs between veins(lower surface).—Absent.Density of erect hairs on veins(lower surface).—Very sparse.Mature leaves (opposite first cluster):Average length.—About 16.8 cm.Average width.—About 20.8 cm.Mature leaf size.—Large.Shape of blade.—Wedge-shaped.Number of lobes.—5.Blade venation.—Palmate.Anthocyanin coloration of main veins on upper side of blade.—Absent.Mature leaf profile.—Undulate.Blistering surface of blade upper surface.—Weak.Leaf blade tip.—In the horizontal plane of the leaf. Mid-vein does not appear to curve downward.Leaf apex.—Acute.Leaf margin.—Serrate.Undulation of margin.—Slight.Undulation of blade between main and lateral veins.—Slight undulation over entire area.Shape of teeth.—Mixture of both sides straight and both sides convex.Length of teeth.—Long.Ratio length/width of teeth.—Medium.Shape of upper lateral sinuses.—Lobes slightly overlapping.Depth of upper lateral sinuses.—Deep.General shape petiole sinus.—Slightly open with a few leaves being half open.Shape of base of upper leaf sinuses.—V-shaped.Tooth at petiole sinus.—Absent.Density of prostrate hairs between veins on lower surface of blade.—Medium to dense.Density of erect hairs between veins on lower surface of blade.—Very sparse.Density of prostrate hairs on main veins on lower surface of blade.—Dense.Density of erect hairs on main veins on lower surface of blade.—Sparse.Density of prostrate hairs on main veins on upper surface of blade.—Sparse.Density of erect hairs on main veins on upper surface of blade.—None or very sparse.Autumn coloration of leaves.—The following colors were observed: Greyed-yellow: 162A and 162B.Upper surface:Color.—Green: 137A.Anthocyanin coloration of main veins(lower surface).—Absent.Color of main veins.—Yellow-green: 145B.Surface appearance.—Dull.Blistering surface of blade.—Medium.Lower surface:Color.—Yellow-green: 146A.Anthocyanin coloration of main veins(lower surface).—Absent.Color of main veins.—Yellow-green: 150D.Glossiness.—Weak.Surface texture.—Smooth.Surface appearance.—Dull.Petiole:Length.—About 16.0 cm.Diameter of petiole2cm from blade.—About 3.3 mm.Petiole color.—The following colors were observed: Yellow-green: 145A and Greyed-purple: 187C.Length of petiole compared to middle vein.—Slightly shorter to equal.Density of prostrate hairs on petiole.—None or very sparse.Density of erect hairs on petiole.—None.Buds:Bud fruitfulness.—Basal: mostly fruitful.Position of first fruitful shoot on previous season cane.—1stto 2ndnode.Dormant bud length.—About 5.6 mm.Dormant bud width in the proximal/distal plane.—About 4.6 mm.Dormant bud color.—The following colors were observed: Greyed-orange: 175A and 175B.Time of bud burst.—Late season: About Mar. 23, 2018.

FLOWERS

FRUIT