Grape plant named `Sunred Seedless`

Abstract

A new and distinct variety of grapevine producing late ripening red seedless table quality grapes which have a high acidity, are short and elliptic in shape, and are large in size.

Description

BACKGROUND

This invention relates to a new and distinct variety of the Vitis vinifera species and is a complex hybrid cross of the `Datal` and `Ruby Seedless`. The new variety was brought to fruiting and asexually reproduced from cuttings taken from the original complex hybrid cross at the Agricultural Research Counsel (ARC)--Nietvoorbij experimental farm in Stellenbosch, Republic of South Africa. The varietal has been named `Sunred Seedless`.

SUMMARY OF THE INVENTION

The `Sunred Seedless` variety may be distinguished from the `Flame Seedless`, which it resembles, by among other things, its ripening/fruit development period, its berry size/shape, its berry color, its leaf size, and its young shoot tip shape. Most notably, the `Sunred Seedless` ripens 4 to 5 weeks after the `Flame Seedless` with a fruit development period of about 103 days from flowering, as opposed to 76 days for the `Flame Seedless`. In addition, the short and elliptical berries of the `Sunred Seedless`, at an average mass of approximately 7.6 g, are naturally larger than the average 5.0 g of the rounded `Flame Seedless` berry. Moreover, the berry color of the `Sunred Seedless` is rose to red gray (R.H.S. 46A-B), becoming dark red when exposed to direct sunlight, whereas the `Flame Seedless` berry is rose in color. Finally, the tip of a young `Sunred Seedless` shoot is open, as compared to the typical semi-opened tip of the `Flame Seedless`.

The `Sunred Seedless` is also distinguishable from the `Flame Seedless` with respect to the density of its bunches, it leaf size, and its acid concentration. The bunches of the `Sunred Seedless`, when no thinning is done, are dense, as opposed to the loose bunches of the `Flame Seedless`. Furthermore, the leaf size of the `Sunred Seedless`, at 23988 mm² (length of the main vein multiplied by the width), is noticeably smaller than the 29855 mm² exhibited by the `Flame Seedless`. Finally, the acid concentration of the `Sunred Seedless` at 20° Brix is 6.0 g/l, whereas the acid concentration of the `Flame Seedless` at 18.8° Brix is 5.9 g/l.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying photographs show typical specimens of the fruit and leaves of the new variety in color as nearly true as it is reasonably possible to make in an illustration of this character.

FIG. 1 illustrates a typical cluster of grapes and stem section of the new `Sunred Seedless` grapevine.

FIG. 2 illustrates a mature leaf (upper surface) of the new `Sunred Seedless` grapevine.

FIG. 3 illustrates a mature leaf (lower surface) of the new `Sunred Seedless` grapevine.

FIG. 4 illustrates vine sections of the new `Sunred Seedless` grapevine.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The following is a detailed description of specimens of the new variety grown at the Agricultural Research Council (ARC)--Nietvoorbij experimental farm in Stellenbosch, Republic of South Africa. Throughout this specification, color names followed by the designation "(R.H.S.)" designate values based on The Royal Horticultural Society Colour Chart (R.H.S. Wilson 1938 edition), and refer to plate numbers in the aforementioned color chart. Other color names signify that the name of the color, as used in common speech, is aptly descriptive.

ORIGIN

This variety arose from a complex hybrid cross of the `Datal` (from `Dattier de Beyrough` and `Muscat d'Alexandrie`) and `Ruby Seedless` (from `Emperor` and `Sultana Moscata`) conducted as part of a breeding program at the Agricultural Research Counsel (ARC)--Nietvoorbij experimental farm in Stellenbosch, Republic of South Africa. Cuttings of the original complex hybrid cross were asexually reproduced on `Jacquez` rootstock by the inventors. The `Sunred Seedless` was grown on a Clovelly soil with irrigation applied through micro-jets. The trellising system was a 1.8 m slanting trellis. The same attributes observed in the original specimen were found precisely to have been duplicated in the progeny. The `Sunred Seedless` is not more or less susceptible to common diseases than other cultivars in the Republic of South Africa.

FRUIT

The fruit of the `Sunred Seedless` can be used as a table grape. It has a crisp texture and a high acidity (6.0 g/l at 20° Brix). The fruit development period is approximately 103 days, with the fruit maturing at the end of February in the Paarl region of South Africa. With a late ripening date of March 3, the berry has a sugar content of 16° Brix.

The average `Sunred Seedless` bunch is 191.2 mm in length and 127.2 mm in width. The average bunch has a mass of approximately 772.2 g. Bunches display a medium to high density. The peduncle has medium lignification and is considered short to very short, with an average length of 38.7 mm.

The berries of the `Sunred Seedless` are naturally large for a seedless grape and, under favorable growing conditions, can range in mass between 6 and 7.5 g. No Gibberellic treatment for berry enlargement is necessary. The berries are short elliptic in shape, have a round cross section, and are typically 26.5 mm long with an average diameter of 21.5 mm. However, the berries are not always uniform. The skin of the `Sunred Seedless` is also not uniform, ranging from rose to red-gray (R.H.S. 46A-B) in color. Typically, the berries are approximately 33% rose and 67% red-gray. However, the percentages depend on the ambient temperature. In particular, the color will darken from rose to red-gray under very hot conditions. The skin of the grape displays a noticeable bloom which lends a visible blue-purple or pale pink cast to the individual grape, ranging from R.H.S. 186D to R.H.S. 85B to R.H.S. 97B in coloration, depending on lighting conditions and the amount of bloom displayed.

The flesh of the `Sunred Seedless` is colorless (translucent) and firm with a medium juiciness. Under certain growing conditions, such as warm weather, rudimentary seeds may occur. However, they are not noticeable when eating. The fruit of the `Sunred Seedless` stores well under cold storage. Specifically, the `Sunred Seedless` has been stored for up to 6 weeks at -0.5°C in a cardboard container, inside a plastic bag, and with a 0.3 g SO₂ liner. Minimal defects as to berry splitting, loose berries, botrytis, and SO₂ damage have been recorded.

VINE

The vines of the `Sunred Seedless` display a medium vigor and produce strong shoots which are very fertile. The average shoot length at bloom is 453 mm and the shoot diameter at the basal end is 12-14 mm. Two bunches per shoot is typical. The young shoots of the `Sunred Seedless` have an open tip which has a red tinge with medium intensity. The density of prostrate and erect hairs on the tip is absent or very sparse.

The dorsal side of the nodes and internodes is green with red stripes, whereas the ventral side of the nodes and internodes is green (with red stripes common). The density of erect and prostrate hairs on the nodes and internodes is absent or very sparse. There are typically two or less tendrils on three successive nodes with an approximate length of 20 cm.

The canes of the vine mature well. The woody shoots are light to medium brown with a striate surface and a round cross section. The length of the internodes is short. The woody shoots display little or no erect hairs on either the nodes or the internodes.

The time of bud burst in South Africa is approximately September 18^th and the vines are 50% in full bloom by November 20^th. The flower of the `Sunred Seedless` is hermaphroditic with a medium size pedicel base. The flower bud is medium, pointed, and green (R.H.S. 143D). The opened flower is green (R.H.S. 143A).

FOLIAGE

The upper side of a young leaf is green in color with bronze spots and displays a medium intensity reddish-purple anthocyanin coloration. The density of prostrate and erect hairs on the abaxial side of young leaves is absent or very sparse.

The mature leaf is pentagonal in shape with a flat to undulated profile and 5 lobes. The teeth are of a medium length, are of equal length and width at the base, and have rectilinear to convex sides. There is little or no blistering on the upper side of the leaf and no creasing of the leaf blade is observable. The upper side leaf color is green (R.H.S. 137C). The lower side leaf color is also green (R.H.S. 143C).

The length of the main vein is approximately 131.3 mm with a width of 182.7 mm. The length of the petiole is approximately 137.2 mm. Thus, the petiole has a length similar to the main vein and exhibits medium reddish-purple anthocyanin coloration on the upper and lower side. The density of prostrate and erect hairs on the petiole is absent or very sparse.

The sinuses at the apex have a medium depth with open to slightly overlapping lobes. The sinuses at the base are slightly V-shaped. The petiole sinus is open with a V-shaped base. The leaves of the `Sunred Seedless` normally turn yellow and begin to fall in early June in South Africa.

Claims

1. A new and distinct red seedless grape plant known as `Sunred Seedless` substantially as shown and described.