Patent Grant
PP34293
Latin name of the genus and species: The Latin name of the novel plant variety disclosed herein is Cercis canadensis.
Variety denomination: The inventive variety of the Cercis canadensis disclosed herein has been given the varietal denomination ‘NC2017-108’.
The present invention comprises a new and distinct hybrid cultivar of Cercis canadensis herein referred to by the cultivar name ‘NC2017-108’. Ornamental redbud ‘NC2017-108’ (Cercis canadensis) was derived from a controlled hybridization of Cercis canadensis ‘Dwarf White’ (white single flowers) (unpatented) and Cercis canadensis ‘Flame’ (double purple flowers) (unpatented). ‘Dwarf White’ was a chance seedling that was discovered in cultivation in Charleston, Ill. by the late Dr. Wesley Whiteside, Professor Emeritus of Botany, Eastern Illinois University. Dr. Whiteside shared plants of ‘Dwarf White’ with J. C. Raulston, faculty member and Director of the North Carolina State University Arboretum (now JC Raulston Arboretum (JCRA)) in 1988, and Dr. Raulston established this variety in the JCRA collection at that time. ‘Flame’ is an old cultivar discovered in the early 1900's in the U.S. Midwest. It was obtained by the JCRA from a nursery in Aiken, S.C. in 1988. The goal of the controlled hybridization was to develop a redbud showing double, white flowers. Double flowers provide distinct ornamental value and are essentially female sterile. Hence, no unsightly seed pods are formed, an asset in the landscape. ‘NC2017-108’ will be an excellent companion to ‘Pink Pom Poms’, a double-pink-flowered cultivar (U.S. Plant Pat. No. 27,630).
The original controlled hybridization to obtain F1 seed was made by hand in March 1999 in Raleigh, N.C. ‘Dwarf White’ (JCRA accession number 020083) was used as the female parent, as trees of ‘Flame’ are female sterile. Pollen was obtained from ‘Flame’ (JCRA accession number 880370) from flowers of the existing tree in the JCRA collection. F1 seed from the controlled hybridization was harvested in August 1999. Seed set was very low, and only two seeds were obtained. After harvest, seeds were acid scarified for 30 minutes in concentrated sulfuric acid, rinsed thoroughly, and subsequently cool-stratified for about 12 weeks in the fall of 1999 to satisfy the seed chilling requirement. Seeds were sown in January 2000 under greenhouse conditions. The two F1 hybrid seedlings were initially grown in the greenhouse for about 4 months, and then subsequently transplanted to larger pots and grown in a research plot in summer 2000. Plants were moved to a permanent field location in Jackson Springs, N.C. in winter 2001, and designated with selection numbers ‘NC99-6-1’ and ‘NC99-6-2’. Both F1 seedlings showed purple, double flowers similar to the male parent when they eventually flowered in 2003.
Because ‘NC99-6-1’ and ‘NC99-6-2’ were both female sterile, development of a F2 family was not possible. Hence, a backcross strategy hybridizing the F1 trees as males to a single-flowered white parent, was employed in an attempt to recover double-flowered white offspring. Backcross hybridizations were conducted in March 2014 in a greenhouse using potted trees. The single-flowered white parent chosen for the backcross hybridization was ‘Royal White’ (unpatented). This cultivar was chosen to reduce the potential for inbreeding depression, as it differs genetically from ‘Dwarf White’ that was used to create the original F1 family. To accomplish the backcross, pollen was obtained and bulked from both F1 selections (male parent) and crossed onto ‘Royal White’ (essentially female parent). Backcross seed was harvested in August 2014. Seed was acid scarified followed by cool stratification for about 3 months beginning fall 2014. Stratified backcross seed was sown December 2014, germinated, and seedlings were grown in the greenhouse during spring/summer 2015. Thirty-six backcross seedlings subsequently were transplanted into the field at the Jackson Springs, N.C. in November 2015. The trees first flowered in 2017. Of the 35 trees, 12 trees showed double, white flowers. The remaining trees were discarded. Over 4 years of observation, all 12 selections were evaluated for flower density, flower size, cold hardiness (lack of trunk winter injury), and tree architecture. ‘NC2017-108’ was chosen as the superior selection based on these criteria.
Propagules of the ‘NC2017-108’ selection were sent to Belvidere, Tenn. in August 2018 for initial propagation and nursery trials by chip budding onto seedling rootstocks of Cercis canadensis. Five trees were propagated. This was the first asexual propagation of ‘NC2017-108’ and all trees maintained their true-to-type identity when asexually propagated in this manner. During all asexual propagation, the characteristics of the original plant have been maintained. Plants derived from chip budding exhibit characteristics identical to those of the original plant, and no aberrant phenotypes have appeared.
‘NC2017-108’ has excellent vigor and shows a distinct semi-upright habit (
This new redbud is illustrated by the accompanying photographs which show the plant's foliage and inflorescences. The colors shown are as true as can be reasonably obtained by conventional photographic procedures. 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 redbud.
The following is a detailed description of the botanical characteristics of the new and distinct variety of the redbud tree known by the denomination ‘NC2017-108’. The detailed description was taken on three-year old to four-year old trees in Jackson Springs, N.C. All colors cited herein refer to The Royal Horticultural Society Colour Chart (The Royal Horticultural Society (R.H.S.), London, 2007 Edition). Where specific dimensions, sizes, colors, and other characteristics are given, it is to be understood that such characteristics are approximations or averages set forth as accurately as practicable.
Regarding comparisons to its parents and other related cultivars, ‘NC2017-108’ differs from its grandparent ‘Flame’ in having double white flowers, in contrast to the double purple flowers of ‘Flame’ and differs from its grandparent ‘Dwarf White’ in having double white flowers in contrast to the single white flowers of ‘Dwarf White’. ‘NC2017-108’ differs from its female parent ‘Royal White’ in having double white flowers in contrast to the single white flowers of ‘Royal White’ and from its male parents NC99-6-1 and NC99-6-2 (pollen bulked) in having double white flowers, in contrast to the double purple flowers of NC99-6-1 and NC99-6-2.
‘NC2017-108’ differs from its closest near relative, half-sib ‘Pink Pom Poms’ (U.S. Plant Pat. No. 27,630) (both have ‘Flame’ redbud as a common parent), in having double white flowers in contrast to the double pink flowers of ‘Pink Pom Poms’.
