<i>Citrus </i>plant named ‘UF 1859’

Abstract

A new and distinct seedless, sweet orange-mandarin hybrid, with distinctive shape and color, that can be harvested through a season extending for at least three months. The new citrus cultivar, named UF 1859, also appears to be more tolerant to HLB than most mandarin varieties, showing standard leaf, foliage, and fruit morphology and dense foliage despite being CLas positive.

Claims

1. A new and distinct Citrus plant named UF 1859 as illustrated and described herein.

Description

DESCRIPTION OF THE FIGURES

(1) The accompanying photographs (as shown in FIGS. 1A-6B) illustrate the overall appearance of the new Citrus cultivar UF 1859. These photographs show the colors as true as can be reasonably obtained in colored reproductions of this type. Colors in the photographs may differ slightly from the color values cited in the detailed botanical description, which accurately describe the colors of the new Citrus cultivar.

(2) FIG. 1A is a photograph of a tree of the new Citrus cultivar UF 1859 showing the overall growth habit;

(3) FIG. 1B is a photograph of a tree of the new Citrus cultivar showing the overall growth habit, including branching;

(4) FIG. 1C is a photograph of a tree of the new Citrus cultivar showing the overall growth habit, including branching;

(5) FIG. 2A is a photograph of immature fruit on a tree of the new Citrus cultivar;

(6) FIG. 2B is a photograph of fruit on a tree of the new Citrus cultivar, the fruit being at color break;

(7) FIG. 2C is a photograph of fruit on a tree of the new Citrus cultivar, the fruit being at the earliest point of internal maturity;

(8) FIG. 2D is a photograph of fruit on a tree of the new Citrus cultivar, the fruit being at full maturity;

(9) FIG. 3A is a photograph of whole fruit, horizontally cut fruit, and vertically cut fruit at full maturity, showing color and unique tendency to have a rounded to truncated stem and blossom end shape (with a metric ruler shown for reference);

(10) FIG. 3B is a photograph of whole fruit and horizontally cut fruit, showing color and unique tendency to have a rounded to truncated stem and blossom end shape;

(11) FIG. 3C is a photograph of whole fruit, horizontally cut fruit, and vertically cut fruit at full maturity, showing color and unique tendency to have a rounded to truncated stem and blossom end shape (with a metric ruler shown for reference);

(12) FIG. 3D is a photograph of whole fruit and horizontally cut fruit, showing color and unique tendency to have a rounded to truncated stem and blossom end shape;

(13) FIG. 4A is a photograph of flower buds on a tree of the new Citrus cultivar;

(14) FIG. 4B is a photograph of flowers and flower buds on a tree of the new Citrus cultivar;

(15) FIG. 4C is a photograph of flowers and flower buds on a tree of the new Citrus cultivar;

(16) FIG. 4D is a photograph of a flower on a tree of the new Citrus cultivar;

(17) FIG. 4E is a photograph of flowers on a tree of the new Citrus cultivar;

(18) FIG. 4F is a photograph of a flower on a tree of the new Citrus cultivar;

(19) FIG. 4G is a photograph of a flower on a tree of the new Citrus cultivar;

(20) FIG. 4H is a photograph of flowers on a tree of the new Citrus cultivar;

(21) FIG. 5A is a photograph of flowers of the new Citrus cultivar, illustrating the size, shape, and color of the flowers in various stages of development (with a metric ruler shown for reference);

(22) FIG. 5B is a photograph of flowers of the new Citrus cultivar (with a metric ruler shown for reference);

(23) FIG. 5C is a photograph of flowers of the new Citrus cultivar (with a metric ruler shown for reference);

(24) FIG. 5D is a photograph of flowers of the new Citrus cultivar (with a metric ruler shown for reference);

(25) FIG. 5E is a photograph of a flower of the new Citrus cultivar (with a metric ruler shown for reference);

(26) FIG. 6A is a photograph of full expanded leaves of the new Citrus cultivar in a range of sizes (with a metric ruler shown for reference); and

(27) FIG. 6B is a photograph of a fully expanded leaf of the new Citrus cultivar (with a metric ruler shown for comparison).

DETAILED BOTANICAL DESCRIPTION OF THE CULTIVAR

(28) In the following description, color references are made to The Royal Horticultural Society (R.H.S.) Colour Chart published by The Royal Horticultural Society in London (second edition), in association with the Flower Council of Holland, except where general terms of ordinary dictionary significance are used. The juice color score disclosed herein is based on the United States Standards for Grades of Orange Juice published by the United States Department of Agriculture (Jan. 10, 1983).

BOTANICAL DESCRIPTION

(29) Botanical classification: Family.Rutaceae. Botanical name.Citrus sp. (complex interspecific triploid Citrus hybrid). Common name.Citrus. Cultivar.UF 1859. Parentage: LB8-9 (U.S. Plant Pat. No. 21,356; sold commercially as Sugar Belle) x (Nova tangelo (unpatented)+Succari sweet orange (Citrus sinensis L. Osbeck; unpatented somatic hybrid). Tree: Ploidy.Triploid. Size.Large. Width across row: Approximately 4.3 meters. Width down row: Approximately 3.7 meters. Tree height.Approximately 4.1 meters. Tree canopy diameter.Approximately 4.3 meters. Density.Canopy of HLB-affected tree is moderately dense. Tree shape (form).Oblate shape (obolid). Trunk: Trunk diameter.Approximately 20 cm at 30 cm above the ground. Trunk texture.Relatively smooth. Trunk bar color.RHS N199 B (Grey-Brown Group). Branches: Branch length.3.5 meter on average. Branch diameter.9.5 cm on average. Crotch angle.Acute (less than 90, averaging 80). Branch texture.Medium rough. Branch color.RHS N 199 B (Grey-Brown Group). Leaves: Size (lamina average).Length: 120 mm on average. Width: 60 mm on average. Length-to-width ratio: 2 on average. Thickness: Relatively thick. Type.Simple (unifoliate). Shape.Elliptical. Apex.Acute. Base.Acute. Margin.Dentated with a split end. Surface.Upper (adaxial) surface: Smooth and shiny. Lower (abaxial) surface: Medium veins that are pinnately netted. Color.Upper (adaxial) surface: RHS N 137 A (Green Group). Lower (abaxial) surface: RHS 138 B (Green Group). Petiole.Shape and attachment: Brevipetiolate; shorter than leaf lamina. Junction between petiole and lamina: Articulate. Shape (petiole wing): Obovate with narrow end at the base. Length: 20 mm on average. Width: 2.5 mm on average. Color: RHS N 137 A (Green Group). Flowers: Type.Hermaphrodite. Arrangement.Flowers borne singly and in clusters of 2-5 flowers each; individual flowers grow from shoot terminals or leaf axils. Flower diameter.Fully open flowers have an average diameter of 32 mm. Flower depth.15 mm on average. Flower blooming period.First bloom: Pinhead bloom usually appears in early February in central Florida, first blossoms open in middle of February. Full bloom: Generally, from late February through middle of March, depending on tree age and season. Fragrance.Fragrant. Flower bud size.Length: Approximately 1.8 mm for the initial visible flower bud; approximately 21 mm for the mature flower buds before opened. Diameter: Approximately 1.5 mm in average in the initial visible flower bud; approximately 6.5 mm in the matured bud. Flower bud shape: Initial visible flower bud with round dome shape; mature flower bud with elongated olive shape. Flower bud color: RHS 144 D (yellow-green) for the initial visible flower bud; RHS NN 155B (white) for mature buds. Reproductive organs: Fertility.Pollen and ovule are sterile. Petals.Number (per flower): 5. Petal length: 21 mm on average. Petal width: 6.5 mm on average. Petal shape: Flat spatula shape. Apex shape: Smooth with obtuse angle. Base shape: Obtuse. Petal color: Upper surface: RHS 155 C (White Group). Lower surface: RHS NN 155 AB (White Group). Margin: Smooth. Sepal.Number (per flower): 5. Shape: Delta shaped with acute angle at apex, although some with flat angle. Length: 3 mm on average. Width: 3.5 mm on average. Apex shape: Acute angle at apex. Margin: Smooth. Color: Upper surface: RHS 158 C (Green White Group). Lower surface: RHS 157 B (Green White Group). Pedicel.Length: 8 mm on average. Diameter: 1.5 mm on average. Color: RHS 144 A (Yellow Green Group). Stamen.Number (per flower): 20 on average. Length: 13.5 mm on average. Anther.Length: 2.5 mm on average. Width: 0.9 mm average. Color: RHS 14A (Yellow Orange Group). Pollen color (general): RHS 13 B (Yellow Group). Pistil.Number (per flower): 1. Length: 13 mm on average. Color: RHS 153C (Yellow Green Group). Style length: 10.5 mm on average. Style diameter: 2 mm on average. Style color: RHS 144 C (Yellow Green Group). Ovary shape: Oval shape. Ovary diameter: 3.5 mm on average. Ovary color: RHS 143 C (Green Group). Fruit: Size.Uniform. Average weight (per individual fruit): 280 grams in average. Length (height): 8.00 cm in average. Diameter: 7.9 cm in average. Shape.Overall: Spherical, with truncated or flattened stem end and blossom end. Horizontal cross-section: Round. Longitudinal cross-section: Round, with truncated or flattened stem end and blossom end, which gives a blocky appearance. Apex: Rounded to truncate. Base: Rounded to truncate. Harvest.Date of first pick: Middle of November. Date of last pick: End of January. Productivity.Small-scale experiments with limited replication have indicated that fruit of the new cultivar UF 1859, when harvested at maturity, show minimal losses due to decay or rind breakdown. Fruit stem.Length: 12 mm on average. Diameter: 5 mm on average. Color: RHS N 199 A (Greyed-Brown Group). Rind.Adherence: Albedo (mesocarp) to flesh (endocarp) is medium to strong; albedo (mesocarp) to peel is medium. Thickness: Medium (3-4 mm on average). Surface texture: Smooth. Color: Flavedo (epicarp): RHS 23 B (Orange Group). Albedo (mesocarp): RHS 14 C (Yellow-Orange Group). Style end: Closed. Rind oil cell density: 95-100 cell/square cm. Oil gland size: Very small size (0.6 mm on average). Flesh.Number of segments: 9-10 on average. Segment walls (thickness): Thin to medium soft, but of sufficient strength to maintain integrity as segments are separated. Segment length: 6.9 cm on average. Segment width: 2.7 cm on average. Juice.Presence: Abundant. Color: RHS 25 B (Yellow-Orange Group). Texture: Soft to medium. Vesicles: Medium thickness. Length: 13 mm on average. Diameter: 3 mm in average. Juice quality (average at full maturity in central Florida, variable by season): Brix: 14.0.Acidity: 0.8%. Ratio (Brix: acidity): 17.5. Juice color score: 37. Seeds.Presence: Seedless. Fruit parthenocarpy: Weak. Resistance to disease: No rigorous systematic testing for disease resistance has been conducted until now. The tree was selected from an orchard devasted by Huanglongbing (Citrus greening disease) based on its health, indicating of substantial tolerance to this disease, and its ability to produce mostly non-symptomatic fruit.

COMPARISON WITH KNOWN CULTIVARS

(30) The new Citrus cultivar UF 1859 is a sweet orange-like hybrid, and although the fruit resemble common sweet oranges in several aspects, it can readily be distinguished based on other characteristics. Fruits have much deeper orange-red external pigmentation compared with common oranges that would mature during the same time, such as Vernia (unpatented) or Valquarius (SF14W-62, U.S. Plant Pat. No. 21,535), and the surface of the peel is much smoother. The flesh and juice color are also deeper and more intense than common sweet oranges, and the taste is sweeter with higher Brix than typical oranges, and aroma notes that some describe as tropical, different from standard sweet orange taste profiles. Fruit shape is unique, with many fruits of UF 1859 displaying a characteristic blocky appearance, because of the conspicuous flattening at both the stem and blossom ends of the fruit, whereas the common oranges are rounded. The foliage of UF 1859 is distinctly different from common sweet oranges; leaves generally are wider, and because the cultivar is triploid, the leaves tend to be thicker and more deeply green, with a coarse feeling surface.

(31) When compared with the female parent, LB8-9, fruit of LB8-9 are typically smaller, have a conspicuous neck, and are bell shaped, whereas fruit of the new cultivar 1859 lack an obvious neck and are more spherical. The fruit of LB8-9 are seeded following cross-pollination, while fruit of UF 1859 are completely seedless under all conditions. When compared with the male parent, (Nova tangelo+Succari sweet orange somatic hybrid), fruit of the male parent are globose and lack a neck and they usually contain a few to many seeds. Fruit of the new cultivar UF 1859 are completely seedless under all conditions. Further, leaves of UF 1859 are relatively thicker than those of LB8-9 by virtue of the plant's triploid condition, and they lack the typical drooping appearance. The leaves of the male parent are thicker than both UF 1859 and those of the female parent as a consequence of its tetraploid condition.