HORTSCIENCE 39(7):1581–1583. 2004. In total, 511 fl owers were self-pollinated on 11 infl orescences of the hybrid. In total, 774 fl owers on 11 infl orescences of B. davidii ‘Nanho A Hybrid of davidii var. Purple’ were self-pollinated. Four panicles of B. lindleyana were self-pollinated, resulting in nanhoensis ‘Nanho Purple’ and a total of 189 fl owers. Fertility of the hybrid relative to both par- B. lindleyana ents was assessed by crossing all three taxa as male parents to B. fallowiana and to B. davidii W. Elliott1, D.J. Werner2 and P.R. Fantz2 ‘White Ball’, ‘Black Knight’, and Department of Horticultural Science, North Carolina State University, Box ‘Dartmoor’, using the hybrid and both parents 7609, Raleigh, NC 27695-7609 as the pollen source. Between 7 and 13 infl ores- cences were pollinated for each combination, Additional index words. Buddleja davidii, Buddleja lindleyana, butterfl y bush, Buddlejaceae, with total fl owers pollinated ranging from Loganiaceae, , breeding, hybrids, RAPD analysis 430 to 1664 fl owers per combination. Seed capsules were harvested at maturity, as defi ned Abstract. A controlled cross between Buddleja davidii var. nanhoensis (Chitt.) Rehd. ‘Nanho by their dried appearance and the beginning of Purple’ and B. lindleyana Fort. ex Lindl. produced a hybrid. Pollen viability, male fertility, dehiscence. The seed capsules were placed in and the fl oral and vegetative characters are presented with a Latin diagnosis. Buddleja paper envelopes, dried for an additional 2 to 3 x luteolufaucia Elliott and Fantz is proposed as the name for this hybrid. Hybridity was d at room temperature, and stored at 4 °C until confi rmed using RAPD analysis. they were sown. For germination, seeds were Buddleja L. (orthogr. syn. Buddleia) consists (Dirr, 1998). A successful interspecifi c hybrid of sown on sterile media (Fafard # 4) and placed of ≈100 (Griffi ths, 1994). The B. davidii var. nanhoensis (Chitt.) Rehd. ‘Nanho under intermittent mist. The number of germi- has been placed in several families including Purple’ and B. lindleyana has been made. The nated seedlings for each cross combination was Scrophulariaceae Juss. (Rogers, 1986) and Lo- objectives of this work described herein are to counted after 3 to 5 weeks. ganiaceae Mart. (Griffi ths, 1994) as well as its verify the hybrid status of the seedling produced, Pollen fertility of the hybrid and both parents own family Buddlejaceae K. Wilh. (Bhattacha- characterize the fl oral and vegetative characters was determined by culturing pollen obtained ryya and Johri, 1998). Most species are tropical of the hybrid, and to validate a name for the from newly opened fl owers on germination or subtropical shrubs originating in Asia, South hybrid taxon. media (Brewbaker and Kwack, 1963). A fi ne Africa, and North and South America. Buddleja camel’s hair brush was used to remove pollen has a number of qualities that make it a desir- Materials and Methods from the anthers of several fl owers representing able ornamental shrub. exhibit extended several infl orescences of the same . Three fl owering periods and produce long panicles of Numerous controlled crosses between B. petri dishes containing media were made for fl owers that attract butterfl ies and bees. Buddleja davidii var. nanhoensis ‘Nanho Purple’ and each taxa. Pollen was placed on the media and are widely adaptable, tolerating poor soil, heat B. lindleyana were made, resulting in a single allowed to germinate for 3 h. Pollen germination and drought, and suffer from few pest problems, hybrid seedling (herein referred to as the hybrid). was measured by examining the pollen under the exceptions being nematodes (Dirr, 1998) ‘Nanho Purple’ was used as the female parent. 100× magnifi cation. Germination was defi ned and spider mites (Gillman, 1998). This seedling was grown in the N.C. State as the pollen tube being at least as long as the Garden use of Buddleja has been limited University Horticultural Science greenhouse in diameter of the pollen grain. This procedure was primarily to B. davidii Franch. However, there Raleigh, and stem cuttings were made of this replicated three times over the course of 5 weeks. are some notable exceptions. ‘Lochinch’ is an individual plant for further testing. Pollen fertility of the hybrid and both parents was offspring of hybridization between B. davidii In Spring 2001, three vegetatively propagated compared using a repeated measures ANOVA, and B. fallowiana Balf., and possesses the specimens each of the hybrid, B. davidii ‘Nanho with data composed of arcsine transformation silvery-gray foliage of B. fallowiana, and the Purple’ and B. lindleyana were transplanted of the percent pollen germination. hardiness, habit and panicle size of B. davidii. outdoors at the Horticultural Field Laboratory Randomly amplifi ed polymorphic DNA ‘Honeycomb’ and ‘Sungold’, both hybrids of B. in Raleigh and grown under standard cultural (RAPD) reactions were performed on leaf globosa Hope and B. davidii, have the yellow conditions. Characterization of floral and samples of the hybrid and each parent to confi rm fl ower color of B. globosa and foliar character vegetative characters of the hybrid and both hybridity. RAPD primers OPAV11, OPW-16, and plant habit intermediate between these two parents were made for two consecutive years. OPX-18, OPAA-11,(AC)8CA, (AC)8CT, species (Dirr, 1998). Winter leaf defoliation was assessed visually in (AC)8TT and (AG)8CC were used in accordance To date, hybridization of the Asian species B. January 2003. with previously reported procedures (Chaparro davidii and B. lindleyana Fort. ex Lindl. has not Color was assessed by observation using et al., 1994). been reported in literature. Buddleja lindleyana the Royal Horticultural Society Colour Chart Vouchers in fl ower of B. davidii ‘Nanho possesses characteristics that would be desirable (Royal Horticultural Society, 1986). Color Purple (6611 and 6613, NCSC; 6612, NA), to incorporate into B. davidii. It has evergreen to designations (e.g., reddish-brown) represent the B. lindleyana (6614 and 6616, NCSC; 6615, semi-evergreen foliage in zones 7 to 9, produces author’s personal perceptions, while the color NA) and the hybrid (6617 and 6619, NCSC; purple-colored panicles that are considerably value designations (e.g., RHS 174A) refer to 6618, NA) were collected by Fantz and Elliott. longer than B. davidii, and can be encouraged to corresponding RHS color chips. Vouchers sent to the United States National grow on a trellis or to weave through the canopy Self- and cross-fertility of the hybrid and Arboretum (NA) included 6612, 6615, and 6618, of a tree, where its long drooping panicles can be both parents were assessed by making controlled and the remaining vouchers were deposited at displayed with maximal effectiveness. Also, B. self- and cross-pollinations in the greenhouse. the NCSU Herbarium (NCSC). lindleyana is considered to be more mite resistant Cross-pollinations were made using standard hybridization procedures. For each pollination, Results and Discussion panicles containing fl owers one to two days Received for publication 21 Jan. 2004. Accepted before anthesis were selected. The fl owers were Morphological comparison of taxa. The for publication 27 Mar. 2004. The authors appreci- hybrid resembles both parents in having ate the contributions of W.E. Kloos for generating emasculated and fresh pollen of the male parent thought; L. Snelling, for support of this project; J. was applied with a camel’s hair brush to the angulate stems, opposite green leaves, purple- Chaparro for conducting the RAPD reactions; and stigmatic surface of each fl ower immediately violet corolla lobes, glabrous ovules, and four J. Dietz for statistical consultation. after emasculation. Pollinations were performed stamens. The infl orescence of each taxa is an 1Graduate student. over a four-month period of time, from July indeterminate thyrse. Fruits are capsules. A 2Professor. through November 2000. summary of distinguishing characters compar-

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11581–1583COLOR.indd581–1583COLOR.indd 11581581 110/28/040/28/04 4:43:584:43:58 PMPM Table 1. A comparison of the hybrid characters with those of the parents Buddleja davidii ‘Nanho Purple’ and B. lindleyana. Characteristic B. davidii ‘Nanho Purple’ Hybrid B. lindleyana Stems Color older stem 165A-B 174A, 175A-B 172A, 174A Dark brown Reddish-brown Reddish-brown Suckering No No Yes Leaves Petiole length (mm) (0) 2–4 0–3 (5) (2) 3–6 (7) Length/width ratio 3.1–5.6 2.3–3.4 1.4–2.2 (2.6) Shape Lanceolate, oblong, oblanceolate, linear Lanceolate, oblong, elliptical Ovate-lanceolate Margin Serrate-crenate Serrate Entire (crenate) Lower surface color 194A-195A-196A 148C, 147B (194A) 147A, 147B, 147C Silver-white Pale green Pale green Lower surface pubescence White tomentose Pale tan on midrib of young leaves Brown pubescence on young leaves Upper surface Dull color Dull color Shiny Winter leaf defoliation 80% 15% 25% Infl orescence Rachis length (mm) 63–110 (125) (5) 85–212 (383) (132) 185–400 (450) Grouping 3, 5, 7 3 3 Flowers Flower length (mm) 13.1–16.9 (18.5) 16.4–21.8 (13.6) 14.3–18.7 Total number fl owers (39) 48–90 (26) 53–133 161–280 Number open fl owers (34) 41–90 3–27 (34) (1) 3–11 Odor Fragrant Nonfragrant Nonfragrant Calyx Width (mm) 0.9–1.6 1.3–2.2 1.8 – 2.3 Corolla Shape Salverform Salverform Tubular Straight Mostly straight, a few Curved curved Pubescence Sparse Dense Dense Lobe/tube width 4.1–7.6 3.0–5.6 1.6–2.8 Color–tube 80B-C 88D 84C, 85A

Tube width (mm) 0.8–1.7 0.9–2.6 1.6–3.0 Lobe width (mm) (5.1) 5.5–8.4 (5.4) 6.1–9.1 4.1–6.1 Color–throat 25A (edge), 28A, 31A 158A, 20C 84C, 85C Orange-yellow Creamy yellow Purplish-white Stamen Length (mm) 12 12 7 Anther color 162A 166A 164A Muddy yellow Dark brown Medium red-brown Filament color 156B 166D,199B Clear, match throat Green-gray Taupe Seed capsules Length (mm) 6–12 6–12 4–6 Width (mm) (0.9) 1.3–2.1 1.9–2.9 (3.4) 2.2–3.6 Length/width 4.6–8.3 (10.8) (2.8) 3.6–4.7 (5.3) 1.1–2.4

ing the hybrid and both parents is presented in juvenile leaves, with less obvious brown pu- lindleyana produced viable seed after self-pol- (Table 1). bescence limited to the veins on mature leaves. lination, unlike B. davidii ‘Nanho Purple’ which The hybrid resembles B. davidii ‘Nanho The undersides of the leaves of the hybrid are lacked self-seed production. Crosses between the Purple’ in several ways. The leaves have a tomentulose on juvenile leaves, and have pale hybrid and B. fallowiana were more successful similar shape, lanceolate to oblong-elliptical, tan pubescence on the midrib. The panicles of than crosses of B. fallowiana with either par- with serrated edges and dull color. Petioles are B. lindleyana are elongate and arch downward, ent (Table 2). Pollen viability of the hybrid is rather short. Also, fl owers of the hybrid resemble with fl owers occurring in sets of three, with only similar to that of B. lindleyana (Table 3). Field B. davidii in shape, in broad lobe width, and sta- a few (3 to 11) fl owers in the panicle open at one observations reveal considerable hybrid seed set, men length. Seed capsules are similar in length. time. The infl orescence of ‘Nanho Purple’ is more suggesting high female fertility as well. There is no evidence of suckering in either the compact, with denser sets of fl owers (sets of 3, 5, Analysis of the RAPD reactions confi rms hybrid or ‘Nanho Purple’. or 7) and fl owers generally blooming simultane- hybrid origin. RAPD primers OPAV-11, OPW- The hybrid resembles B. lindleyana in several ously (41 to 90). The infl orescence of the hybrid 16, and OPX-18 amplifi ed clear, reproducible ways. The color of the older stems is similar. The is intermediate in length, with 3 to 27 fl owers bands that show hybrid origin (Fig. 2). Buddleja underside of the leaf is similar in pubescence open at one time (Fig. 1). The individual corolla lindleyana is a diploid species, possessing 38 and is almost concolorous. There is very little tube length of the hybrid fl ower is greater than chromosomes whereas B. davidii is a tetraploid winter leaf defoliation. Flowers are similar to either parent. The ratio of the width of the corolla species with 76 chromosomes (Moore, 1947). B. lindleyana in that they are grouped in sets of lobe to the width of the tube is intermediate. The A successful hybridization between these two three, lack fragrance, have broader calyxes, and color of the hybrid’s throat is a creamy yellow, species might be expected to result in a triploid the outer corolla tube is densely pubescent and whereas the throat of B. lindleyana is the same hybrid, unless B. lindleyana produces unre- sparkles when the light hits the hairs. pale purple color of the tube, and the throat of duced (2x) gametes, resulting in a tetraploid. The hybrid displays characteristics intermedi- B. davidii has an orange-yellow eye. The fertility of the hybrid suggests that it is ate between the two parents. The length to width Fertility. The hybrid is fertile as a male parent, a tetraploid, and suggests that B. lindleyana ratios of the leaves and of the seed capsule are generally similar to B. davidii ‘Nanho Purple’, produces unreduced gametes. intermediate. The leaf undersides of B. davidii based on the number of viable seed produced Culture. The hybrid is easy to root from are tomentose, even canescent. The leaf under- per pollinated fl ower on selected cultivars of B. softwood and semi-hardwood stem cuttings. sides of B. lindleyana have brown pubescence davidii female parents. Both the hybrid and B. Flowers are formed on new growth, thus prun-

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11581–1583COLOR.indd581–1583COLOR.indd 11582582 110/28/040/28/04 4:44:014:44:01 PMPM Fig. 1. Infl orescence of Buddleja davidii x B. lindleyana hybrid. ing before spring growth is recommended. The B. lindleyana for improvement in the hybrid seems to grow best under cooler tempera- tetraploid B. davidii. tures, as compared to B. davidii, and extends the Hybrid nomenclature and morphology. Bud- fl owering season into fall. It appears to be more dleja x luteolufaucia Elliott and Fantz {Buddleja shade tolerant than many Buddleja. davidii var. nanhoensis (Chitt.) Rehd. x Buddleja Availability. Currently, the hybrid is not in lindleyana Fort. ex Lindl.} distingibili infl ores- general commerce. Propagules can be obtained centia thryso laxo; fl oribus ternatis, purpureis, from Dennis Werner, Department of Horticul- nonodoriferis; corolla tubo elongato, pubencenti ture, N.C. State University, Raleigh. denso et lucenti, cum fauce fl avo cremeo. Shrub, low mounding, currently to 1.1 m tall × Conclusion 2 m wide. Stems angulate, slightly winged; older stems reddish-brown (174A, 175 A–B). Leaves Fig. 2. RAPD banding patterns of Buddleja davidii The hybrid exhibits characteristics of both are opposite, lanceolate, acute to acuminate, (lane 2), B. lindleyana (lane 3), and the B. davidii parents, as well as a number of intermediate cuneate to attenuate, serrate, dull green above x B.lindleyana hybrid (lane 4) using primer OPAV- 011. Lane 1 = 1 kb molecular marker. Top arrow traits. Flowers tend to be larger than either (147A) and paler green below (147B, 148C), shows a 0.8 kb band found in only B. lindleyana parent with an extended blooming period. The 32 to 83 mm long and 10 to 30 mm wide; pale and the hybrid. The bottom band shows a 0.74 kb hybrid grows better in cooler temperatures, loses tan pubescence on lower surface ribs of young band found only in B. davidii and the hybrid. fewer leaves in winter, and is more fl orifer- leaves; petiole 0 to 3 mm. Infl orescence is an ous. Therefore, it will be a useful addition for indeterminate thyrse with fl owers in groups of mm wide; stamens four, 12mm long; ovary landscape plantings. The hybrid is successful in 3; rachis to 383 mm long. Flowers are odorless, glabrous. Seed capsule 8 to 12 mm long, 1.9 to producing viable seed from controlled crosses salverform; calyx 3.1 to 5.8 mm long, 1.3 to 3.4 mm wide. Holotype: Fantz and Elliott 6617 with other Buddleja species, in contrast with 2.2 mm wide with fi ne hairs; corolla densely (NCSC); Paratypes: Fantz and Elliott 6618 (NA) limited fertility of B. lindleyana in such cases. pubescent and glistening, soft bluish-violet (80 and 6619 (NCSC). The hybrid can provide stock material for intro- to 81A, 82A, 87B) with throat creamy yellow ducing desirable characteristics of the diploid (158A, 20C), 16 to 22 mm long, lobes 6 to 9 Literature Cited Bhattacharyya, B. and B.M. Johri. 1998. Flowering plants: Table 2. Male fertility of a Buddleja davidii ‘Nanho Purple’ x B. lindleyana hybrid and both parents and phylogeny. Narosa Publ. House, New as measured by the average number of viable seeds produced per pollinated fl ower after controlled Dehli. hybridization of each to three cultivars of B. davidii (‘White Ball’, ‘Black Knight’, and ‘Dartmoor’) Brewbaker, J.L. and B.H. Kwack. 1963. The essential role and to B. fallowiana ‘Alba’. of calcium ion in pollen germination and pollen tube growth. Amer. J. Bot. 50:859–865. Male Female parent Chaparro, J.X., D.J. Werner, D.O. Malley, R.R. Sederoff. parent White Ball Black Knight Dartmoor B. fallowiana 1994. Targeted mapping and linkage analysis of morpho- logical, isozyme, and RAPD markers in peach. Theor. B. davidii ‘Nanho Purple’ 0.43 6.69 2.49 1.18 Appl. Genet. 87:805–815. z Hybrid 0.58 4.57 3.43 2.36 Dirr, M.E. 1998. Manual of woody landscape plants: Their B. lindleyana 0.0016 0.0027 0.0031 0.0054 identification, ornamental characteristics, culture, th zF hybrid of B. davidii var. nanhoensis ‘Nanho Purple’ x B. lindleyana. propagation and uses. 5 ed. Stipes Publ. Co., Cham- 1 paign, Ill. z Gillman, J.H. 1998. Resistance of Buddleia L. taxa to the Table 3. Pollen viability of the hybrid and both parents as determined by in vitro pollen germination. two-spotted spider mite. (Tetranychus uriticaeKoch). Percent germination PhD diss. Univ. Ga., Athens. y Griffi ths, M. 1994. The new Royal Hortcultural Society index Taxa Time 1 Time 2 Time 3 Mean of garden plants. Macmillan, London. B. davidii ‘Nanho Purple’ 5 6 1 4 a Moore, R.J. 1947. Cytotaxonomic studies in the Logania- Hybridx 35 44 10 25 b ceae. I. Chromosome numbers and phylogeny in the B. lindleyana 23 63 16 37 b Loganiaceae. Amer. J. Bot. 34:527–538. zViability determined as percentage germination after 3 h of incubation on Brewbaker and Kwack (1963) media. Rogers, G.K. 1986. The genera of Loganiaceae in the south- eastern United States. J. Arnold Arbor. 67:143–185. yMeans followed by different letters are signifi cantly different at P = 0.05 (LSD test). Royal Horticultural Society. 1986. Royal Horticultural Society xF hybrid of Buddleja davidii ‘Nanho Purple’ x B. lindleyana. 1 colour chart. Royal Hort. Soc., London.

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