<i>Citrus </i>plant named ‘18A-9-39’

Abstract

A new and distinct cultivar of citrus plant named 18A-9-39, characterized by an easy-to-peel, nearly seedless, tangerine-type fruit with a very rich, sweet, and pleasant flavor; high sugar content in the fruit; vibrant orange fruit color; and good tolerance to HLB, especially when trees are supplemented with controlled release fertilizer (CRF) containing an enhanced micronutrient package.

Claims

1. A new and distinct cultivar of Citrus plant named 18A-9-39 as illustrated and described herein.

Description

DESCRIPTION OF THE FIGURES

(1) The accompanying photographs (as shown in FIGS. 1-12) illustrate the overall appearance of 4.5-year-old plants of the new Citrus cultivar 18A-9-39. 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. It is noted that all of the photographs shown in the Figures were taken of trees with HLB infections.

(2) FIG. 1 and FIG. 2 show whole and cut fruit of the new Citrus cultivar 18A-9-39 as shown and described herein;

(3) FIG. 3 shows whole and sectioned fruit of the new Citrus cultivar;

(4) FIG. 4 shows peeled fruit of the new Citrus cultivar;

(5) FIG. 5 shows whole fruit and cut foliage of the new Citrus cultivar;

(6) FIG. 6 shows flowers and foliage of the new Citrus cultivar;

(7) FIG. 7 and FIG. 8 show close-up views of mature flowers of the new Citrus cultivar;

(8) FIG. 9 shows fruit on a branch of the new Citrus cultivar;

(9) FIG. 10 shows a close-up view of leaves of the new Citrus cultivar; and

(10) FIG. 11 and FIG. 12 show the overall plant growth habit of the new Citrus cultivar.

DETAILED BOTANICAL DESCRIPTION OF THE CULTIVAR

(11) The following detailed description of the new Citrus cultivar 18A-9-39 was obtained using a 4-5 year-old tree growing on UFR-17 rootstock in Lake Alfred, Florida, growing in well-drained sands and soil with poor organic content. The tree was growing under subtropical growing conditions, with hot, humid, and rainy summers (June through August) and mild but variable weather the rest of the year, and generally with a few mild freezes. Leaf and flower data was collected in March, and mature fruit data was collected in November. The colors (except those in common terms) are described from R. H. S. Colour Chart published by The Royal Horticultural Society in London (Second Edition), in association with the Flower Council of Holland.

Botanical Description

(12) Botanical classification: Family.Rutaceae. Botanical name.Citrus sp. Common name.Mandarin. Cultivar.18A-9-39. Parentage: The new Citrus cultivar 18A-9-39 is a triploid hybrid from an interploid cross of a diploid monoembryonic Clementine mandarin (Citrus clementina or Citrus reticulata) (female parent; not patented) crossed with an allotetrapliod somatic hybrid (protoplast fusion) of [LB8-9 (U.S. Plant Pat. No. 21,356, commercially available as Sugar Belle) (Clementine mandarin, Citrus clementina or Citrus reticulata x Minneola tangelo (Duncan grapefruit, Citrus paradisi x Dancy tangerine (Citrus reticulata)]+[Murcott tangor (Citrus reticulata Blanco x Citrus sinensis L. Osbeck) (not patented)] (unnamed pollen parent; not patented). Propagation: Field trees were propagated using standard Citrus nursery techniques. Rootstock liners were grown from nucellar seed, and the scion was grafted onto the rootstock using the standard inverted T graft method. Tree description: Ploidy.Triploid. Size.Medium. Tree height.2.8 meters. Tree canopy diameter.2.8 meters. Vigor.Moderate. Density.Canopies are moderately dense. Tree shape (form).Oblate shape. Growth habit (current season).Both upright and lateral growth. Trunk: Trunk diameter.7.5 cm at 30 cm above the ground. Trunk texture.Relatively smooth. Trunk bark color.RHS N199 D (Grey-Brown Group). Branches: Branch length.2.1 meters on average. Branch diameter.2.9 cm on average. Crotch angle.Acute, being 80-85 degrees on average (less than 90 degrees) in the middle of the tree, while some on the outside of the tree are obtuse, being 100-105 degrees on average (more than 90 degrees). Branch texture.Medium rough. Branch color.RHS 199 B (Grey-Brown Group). Branch spines.Newly propagated plants have very small spines on the initial primary stem growing from the grafted bud, and not on any other subsequent branches. The length of each branch spine is less than 10 mm. There is one spine per node on the initial stem, and they disappear over time. Foliage description: Size (lamina average).Length: 97 mm on average. Width: 45 mm on average. Length to width (L:W) ratio: 2:4 on average. Thickness.Relatively thick. Type.Simple (unifoliate). Shape.Elliptical. Apex: Retuse. Base: Acute. Margin.Dented with a split end. Surface.Upper surface: Smooth. Lower surface: Medium venation, with veins being pinnately netted. Color.Upper (adaxial) surface: RHS N 137B (Green Group). Lower (abaxial) surface: RHS 139C (Green Group). Petiole.Shape and attachment: Brevipetiolate; shorter than leaf lamina. Shape (petiole wing): Obovate with narrow end at the base. Length: 10 mm on average. Width: 1 mm on average. Color: RHS N 137C (Green Group). Inflorescence description: Flower type.Hermaphrodite. Flowering bearing.Single or cluster. Branches have flowers grown in cluster, and each cluster consists of 3-6 flowers. Individual flowers grow from leaf terminals and leaf axillaries. Flower diameter.Fully open flower with average diameter of 24 mm. Flower depth.18 mm on average. Flower blooming period.Generally March, but depends on weather pattern. First bloom: Late February. Full bloom: March. Fragrance.Fragrant. Flower bud size.Length, initial visible flower bud: 1.5 mm on average. Length, mature buds before opening: 20 mm on average. Diameter, initial visible flower bud: 1.3 mm on average. Diameter, mature bud: 5.3 mm on average. Flower bud shape.Initial visible flower bud with round dome shape; mature flower bud with elongated olive shape. Flower bud color (RHS).Initial visible flower bud: 144B (Yellow Green Group) for the initial visible flower bud. Mature bud: RHS NN 155C (White Group) for mature buds. Fertility.Appears to be self-fertile. Petals.Number (per flower): 5. Petal length: 15 mm on average. Petal width: 5.2 mm on average. Petal shape: Flat spatula shape. Apex shape: Smooth with obtuse angle. Base shape: Obtuse. Color: Upper surface: RHS NN 155B (White Group). Lower surface: RHS NN 155A (White Group). Margin: Smooth. Sepals.Number (per flower): 5. Shape: Delta-shaped with acute angle at the apex; however, some have a flat angle at the apex. Width: 2.5 mm on average. Apex shape: Acute angle at apex; however, some have a flat angle at the apex. Margin: Smooth. Color: Upper surface: RHS 157B (Green White Group). Lower surface: RHS 157C (Green White Group). Pedicel.Length: 9.5 mm on average. Diameter: 1 mm on average. Color: RHS 144D (Yellow Green Group). Stamen.Number (per flower): 22 on average. Length: 11.5 mm on average. Anther.Length: 2 mm on average. Width: 0.8 mm on average. Color: RHS 14A (Yellow Orange Group). Pollen color (general): RHS 13B (Yellow Group). Pollen amount: Abundant. Pistil.Number (per flower): 1. Length: 10 mm on average. Color: RHS 154B (Yellow Green Group). Style length: 9 mm on average. Style diameter: 1 mm on average. Style color: RHS 144D (Yellow Green Group). Ovary shape: Oval shape. Ovary diameter: 2.5 mm on average. Ovary color: RHS 145B (Yellow Green Group). Fruit: Size.Uniform, small to medium in size. Average weight (per individual fruit).140 grams. Length (height).6.0 cm on average. Diameter.6.7 cm on average. Shape.Spherical, with the broadest part of the fruit being located slightly below the middle. Shape (cross section).Round. Apex.Round. Base.Round. Harvest.Date of first pick: Early December in Florida. Date of last pick: Late January in Florida. Fruit stem.Length: 10 mm on average. Diameter: 3 mm on average. Color: RHS 189A (Greyed-Green Group). Rind.Adherence: Adherence of albedo (mesocarp) to flesh (endocarp) is weak and the rind is easy to peel. Thickness: Thin; 3-4 mm on average. Firmness: Medium firm. Surface texture: Medium smooth. Color: Flavedo (epicarp): RHS N25B (Orange Group). Albedo (mesocarp): RHS 19C (Yellow-Orange Group). Style end: Closed. Rind oil cell density: 100-150 cells/square cm. Oil gland size: Big; 0.9 mm on average. Flesh.Number of segments: 11 on average. Segment length: 5.5 cm on average. Segment width: 2.5 cm on average. Juice.Presence: Abundant. Color: RHS 24A (Orange Group). Texture: Soft to medium. Vesicles: Length: 10 mm on average. Diameter (thickness): 3 mm on average. Juice quality: Brix: 13.5-17 (increases as fruit is held on tree). Acidity (average): 0.8%. Ratio: 16.8-21 (increases as fruit is held on tree). Juice color: 39.5 (Citrus Index Number). Lb. solid/box: Not available. Seeds.Number: 0-3 seeds per fruit, with an average of 2 seeds per fruit in trees with cross pollination. Shape: Tear-drop shaped. Length: 8-15 mm. Diameter: 3.7 mm. Color: Outer seed coat: RHS 159C (Orange-White). Inner seed coat: RHS 165B (Greyed-Orange). Embryo and cotyledon: RHS 158B (Yellow-White). Resistance to disease: Susceptible to HLB (Huanglongbing), but more tolerant than most mandarin varieties known to the Inventor, especially when trees are supplemented with controlled release fertilizer (CRF) containing an enhanced micronutrient package. No other disease issues have been observed, including Citrus canker or Alternaria spp. Fruit productivity rating (scale of 1-5 with 1 being very low fruit production and 5 being maximum fruit production, in comparison with other commercial varieties known to the Inventor): 18A-9-39 score is 5. HLB disease index rating (scale of 1-5 with 1 being very poor health, near death, and 5 being completely healthy, in comparison with other commercial varieties known to the Inventor). The score of 18A-9-39 is 4.

Comparison with Known Cultivars

(13) The new Citrus cultivar 18A-9-39 can be distinguished from later season W. Murcott and Tango varieties (for example, those sold commercially as CUTIES? and HALOS?) in that the color of the fruit of the new cultivar 18A-9-39 develops much more robustly under typical Florida conditions than these commercial varieties, and the fruit of 18A-9-39 is also more flavorful. However, fruit from cross-pollinated blocks can contain an average of 2 seeds per fruit, whereas the commercial varieties CUTIES? and HALOS? rarely have seeds due to cultivation practices (for example, W. Murcott trees in California are covered with nets during bloom to prevent cross pollination, and thus seed production in the fruit; otherwise, W. Murcott fruit contains many seeds). Evidence suggests that most of the fruit of 18A-9-39 will be seedless if the trees are grown in a solid block (for example, as the commercial variety Sugar Belle), especially if planted blocks are not immediately adjacent to sweet oranges or grapefruit.

(14) The new Citrus cultivar 18A-9-39 can be distinguished from its parental cultivar Clementine in that 18A-9-39 displays later maturity and a more robust flavor. The new Citrus cultivar 18A-9-39 can be distinguished from its parental cultivar Murcott in that 18A-9-39 has a more vivid orange external color, whereas Murcott has a poor external color. The new Citrus cultivar 18A-9-39 can be distinguished from its parental cultivar LB8-9 (Sugar Belle) and somatic hybrids fruit of [Murcott+LB8-9] in that fruit of 18A-9-39 are smaller than those of LB8-9 and somatic hybrids fruit of [Murcott+LB8-9].