Patent Application
20070150991
The present invention relates to a new and distinct cultivar of flowering dogwood, which is resistant to powdery mildew and has supernumerary bracts. This dogwood is botanically known as Cornus florida L. and hereinafter referred to by the following cultivar name: ‘Appalachian Joy’.
This new dogwood cultivar was discovered in a field planting of approximately 1,100,000 C. florida seedlings in Decherd, Tenn. in 1995. ‘Appalachian Joy’ is a supernumerary bracted (more than four bracts), white flowering dogwood, which, to the knowledge of the inventors, is superior to most other cultivars of flowering dogwood and similar to ‘Karen's Appalachian Blush’ (U.S. Plant Pat. No. 13,165 P2), ‘Kay's Appalachian Mist’ (U.S. Plant Pat. 13,098 P2) and ‘Jean's Appalachian Snow’ (U.S. Plant Pat. No. 13,1099 P2) with respect to powdery mildew resistance. Asexual reproduction of ‘Appalachian Joy’ by terminal cuttings harvested at the Tennessee Agricultural Experiment Station in Knoxville, Tenn. and grafting of axillary buds onto seedling rootstocks have shown that the unique features of this new dogwood cultivar are stable and reproduced true-to-type in successive generations.
The parental lineage of this cultivar is unknown. ‘Appalachian Joy’ is a white flowering dogwood cultivar with supernumerary bracts isolated from a field planting of approximately 1,100,000 Cornus florida seedlings in Decherd, Tenn. Seeds in this field were bulked from collections of wild and landscape trees growing in Tennessee, North Carolina, Alabama and Georgia. This cultivar may be reproduced asexually by rooted cuttings and by grafting axillary buds onto seedling rootstock.
‘Appalachian Joy’ has supernumerary white (Green-White Group 157 D: All color classifications are based on The Royal Horticultural Society's Colour Chart) bracts. The primary pairs of bracts slightly overlap and are wider (46 mm) than they are long (38 mm) (n=44). The greatest overall width of the inflorescences averages approximately 81 mm (n=38). The supernumerary bracts, when present, are on average about one-half the size of the primary bracts and range from 1 to 4. The number of bracts subtending receptacles ranges from 4 to 8 and averages about 5.6 (n=44). The clefts are Orange-Red (35 B) at the end of the bracts may be either flat or pointed and may or may not have deep Orange-Red (35 B) pigmentation. Flower petals are Yellow-Orange (14 B) with Red (42D) sepals and Yellow (13 D) anthers. There are about 23 flowers per inflorescence (n=44).
‘Appalachian Joy’ is a supernumerary bracted (more than four (4) and up to eight (8) bracts), white flowering dogwood, which, to the knowledge of the inventors, is superior to most other cultivars of flowering dogwood and similar to ‘Karen's Appalachian Blush’ (U.S. Plant Pat. No. 13,165 P2), ‘Kay's Appalachian Mist’ (U.S. Plant Pat. No. 13,098 P2) and ‘Jean's Appalachian Snow’ (U.S. Plant Pat. No. 13,1099 P2) with respect to powdery mildew resistance. This cultivar has been rated for powdery mildew resistance for five (5) years. Ratings for the cultivars listed in Table 1 were obtained using the following scale: 0=healthy; 1=≦of foliage with signs or symptoms of powdery mildew; 2=≦10% of foliage with signs or symptoms of powdery mildew; 3=≦25% of foliage with signs or symptoms of powdery mildew; 4=≦50% of foliage with signs or symptoms of powdery mildew; 5=>50% of foliage with signs or symptoms of powdery mildew. A summary is provided in Table 1 for 2002 through 2005 data collected at Ellington Agricultural Center, Nashville, Tenn.
DNA amplification fingerprinting (DAF) was used to type ‘Appalachian Joy’. The methodology followed that of Trigiano and Caetano-Anolles (HortTechnology, 8:413-423 [1998]). Data, obtained from 144 loci generated from genomic DNA using six (6) arbitrary octomeric primers, were used to compare ‘Appalachian Joy’, the subject of his application, to other dogwoods including patented powdery mildew resistant cultivars [‘Karen's Appalachian Blush’ (U.S. Plant Pat. No. 13,165 P2), ‘Kay's Appalachian Mist’ (U.S. Plant Pat. No. 13,098 P2) and ‘Jean's Appalachian Snow’ (U.S. Plant Pat. No. No. 13,1099 P2)] and other commonly found cultivars in nurseries, including C. florida ‘Plena’, which also exhibits supernumerary white bracts, but is sterile and C. florida ‘Cherokee Brave’, a red-bracted cultivar, which exhibits some resistance to powdery mildew. The sequence of the primers were the following (5′ to 3′): GAG CCT GT; GAT CGC AG; GTA TCG CC; AAT GCA GC; CTA ACG CC; and GTA ACG CC. DAF as well as cluster analyses were completed using the NTSYS-pc program, version 2.2 (Exeter Software, 100 N. Country Road, Sedtauket, NT 11733). A similarity index is provided in
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The following observations, measurements and comparisons describe this cultivar grown in Oak Ridge and Nashville Tenn. Dogwoods used for this description were about seven (7) years old and planted on six-foot centers with other dogwoods. Plant hardiness is expected to be zones 5-9.
The following descriptions uses color references to The Royal Horticultural Society Colour Chart, except where general terms of ordinary dictionary significance are used. All color ratings were on adaxial surfaces. Ratings for abaxial surfaces were not obtained because reflected/refracted light, due to the density of pubescence on abaxial surfaces, made accurate color determinations difficult or impossible. Measurements are provided as a range with the middle value providing the average (lower limit <average value <upper limit).
