rudbeckia are new species for the Postharvest Evaluation of Cut Dahlia, cut flower industry. ‘Karma Thalia’ Linaria, Lupine, Poppy, Rudbeckia, dahlia, ‘Jemmy Royal Purple’ trache- lium, and ‘Sun Gold’ and ‘Benary’s Trachelium, and Zinnia Giant Scarlet’ zinnias are established species in the cut flower industry, 1,4 2 3 but the cultivars are new. The lack of John M. Dole , Zenaida Viloria , Frankie L. Fanelli , information about postharvest han- and William Fonteno1 dling of the above-listed species and cultivars makes it necessary to de- velop efficient and practical techniques ADDITIONAL INDEX WORDS. hydrator, preservative, cold storage, ethylene sensitivity, for flower producers, wholesalers, 1-MCP, silver thiosulfate, sucrose and retailers to enhance quality and SUMMARY. Vase life of ‘Karma Thalia’ dahlia (Dahlia ·hybrida), ‘Lace Violet’ linaria longevity. (Linaria maroccana), ‘Sunrise’ lupine (Lupinus hartwegii ssp. cruickshankii), The available literature describ- ‘Temptress’ poppy (Papaver nudicaule), ‘Indian Summer’ rudbeckia (Rudbeckia ing how vase water quality affects cut ·hybrida), ‘Jemmy Royal Purple’ trachelium (Trachelium caeruleum), and ‘Benary’s flower quality is variable, and recom- Giant Scarlet’ and ‘Sun Gold’ zinnias (Zinnia elegans) was determined after being mendations differ regarding the use subjected to postharvest handling procedures. Cut dahlia, lupine, poppy, rud- of tap or deionized (DI) water (Nowak beckia, trachelium, and ‘Sun Gold’ and ‘Benary’s Giant Scarlet’ zinnia flowers could and Rudnicki, 1990; Sacalis, 1993). be held in unamended tap or deionized (DI) water with no effect on vase life. Vase In some studies, tap water produced life of linaria was longest when placed in DI water with 8-hydroxyquinoline citrate the shortest vase life (Kamataka, and a solution pH of 3.5. A vase solution of 2% sucrose without foam extended consumer vase lives for linaria, trachelium, and ‘Benary’s Giant Scarlet’ zinnia. 2003), but in others, it resulted in a Floral foam or 2% or 4% sucrose had no effect on the consumer vase life of dahlia, longer vase life than DI water (van lupine, rudbeckia, and poppy. Trachelium and rudbeckia did not tolerate a 20% Meeteren et al., 2000). sucrose treatment for 24 h, whereas linaria and ‘Benary’s Giant Scarlet’ zinnia had a Adding sucrose, typically through longer vase life with a 10% sucrose pulse than a water-only pulse. For trachelium, the the use of commercial premixed longest (17.5 days) consumer vase life occurred when the Chrysal Professional 2 products, to the vase solution en- Processing solution (CP2) was used after pretreatment with DI water. Either of two hanced postharvest performance and commercial holding solutions, CP2 or Floralife Professional (FLP), similarly flower quality of many species (Cho extended the vase life of linaria. The use of FLP or CP2 improved consumer vase life et al., 2001; Jones et al., 1993; Sacalis, of dahlia, lupine, and poppy compared with DI water. Dahlia, trachelium, and 1993). Incorporating biocides in the zinnia flowers could not be cold stored at 2 °C. Lupine and poppy could be stored at 2 °C wet or dry for 2 weeks. Linaria and rudbeckia could be cold stored for 3 weeks. vase solutions decreases microbial Lupine and trachelium were susceptible to 1 mLÁL–1 exogenous ethylene, which growth and therefore maintains induced floret abscission in lupine and stopped floret opening in trachelium. 1- healthier vascular tissue. Results may Methylcyclopropene and silver thiosulfate similarly suppressed the ethylene effect. be cultivar specific as vase life of Cut linaria, zinnia, dahlia, rudbeckia, and poppy flowers were unaffected by ‘Florex Gold’ calla lily (Zantedeschia exogenous ethylene. elliottiana) was extended after a 2-h pulse in 8-hydroxyquinoline citrate pecialty cut flowers comprise a that the customers—wholesalers, re- (8-HQC), while the same treatment large number of species, includ- tailers, and the final consumer—will reduced longevity and quality in Sing trees, shrubs, and herbaceous be satisfied and return to purchase ‘Black Magic’ calla lily (Janowska annuals and perennials. Two key as- more flowers. and Jerzy, 2004). A 24-h pulse in pects of the specialty cut flower indus- Of the many cut flowers intro- 8-HQC increased the longevity of try are introducing new species and duced to commercial markets each sunflower (Helianthus annuus) and marketing flowers with a long post- year, several show potential. ‘Lace Vio- weigela (Weigela spp.) but reduced harvest life. Interesting new cut flower let’ linaria, ‘Sunrise’ lupine, ‘Tempt- the vase life of yarrow (Achillea) species excite buyers and increase sales, ress’ poppy, and ‘Indian Summer’ (Redman et al., 2002). and a long postharvest life ensures Department of Horticultural Science, North Carolina State University, Raleigh, NC 27695-7609 Units To convert U.S. to SI, To convert SI to U.S., We gratefully acknowledge support from the Ameri- can Floral Endowment, Association of Specialty Cut multiply by U.S. unit SI unit multiply by Flower Growers Research Foundation, and numerous 29.5735 fl oz mL 0.0338 suppliers. 0.3048 ft m 3.2808 We would like to thank Ingram McCall for producing 3.7854 gal L 0.2642 the cut flowers and assisting with the postharvest 2.54 inch(es) cm 0.3937 studies, and Beth Harden and Diane Mays for assisting 1 mmho/cm dSÁm-1 1 with the postharvest studies. 28,350 oz mg 3.5274 · 10-5 1Professor. 1 ppb nLÁL-1 1 -1 2Postdoctoral Research Assistant. 1 ppm mgÁL 1 0.001 ppm mLÁL-1 1000 3 Graduate Research Technician. 1 ppm mLÁL-1 1 4Corresponding author. E-mail: [email protected]. (°F – 32) O 1.8 °F °C(1.8·C) + 32 • July–September 2009 19(3) 593 RESEARCH REPORTS The ability for new cuts to per- bedding plant flats (35 mL volume ‘Karma Thalia’ dahlia, ‘Indian form well in floral foam is important, per cell) and were germinated at 16 ± Summer’ rudbeckia, and ‘Sun Gold’ especially to florists. Generally, when 1 °C. Linaria seedlings were trans- and ‘Benary’s Giant Scarlet’ zinnia flowers are placed in floral foam, the planted on 17 Dec. 2002 into 4-inch- plants were field grown at 30 · 30 vase life is decreased (Sacalis, 1993), diameter (325 mL) pots spaced at 4 · cm spacing in a 4-ft-wide bed. Rooted but cut big bend bluebonnet (Lupi- 4 inches. Trachelium seeds were sown dahlia cuttings were received from a nus havardii) stems performed as well into open flats on 7 Jan. 2004 and commercial propagator and were in floral foam as in water (Davis et al., were transplanted on 4 March into planted in the field on 29 Apr. 1995). 806 bedding plant flats, which were 2003. Rudbeckia and zinnia seeds Cold storage is used to delay cut then transplanted on 3 May to stand- were directly sown on 28 Jan. and flower development and provide a ard bulb crates (52 · 38 cm, 11 cm 30 Mar. 2003, respectively, into 806 long vase life (Cevallos and Reid, deep) in a 4 · 5 arrangement (7.5 · bedding plant flats (35 mL volume 2001; Faragher et al., 1984; Redman 9.5 cm apart). Lupine seeds were per cell) using a peat-based commer- et al., 2002). In addition, antiethylene- directly sown on 25 Feb. 2004 into cial root substrate (Fafard 4P). Seeds binding products have been success- 6-inch-diameter (1160 mL) pots were germinated at 16 ± 1 °Cin fully used on ethylene-sensitive species spaced at 6 · 6 inches. Poppy seedlings a polyethylene-covered greenhouse. (Geertsen, 1990; Ichimura et al., were received from a commercial Seedlings were transplanted into the 1998; Newman et al., 1998; Reid, grower and were transplanted on field on 20 March (rudbeckia) and 27 2004), but they have no effect on 7 Jan. 2003 into 6-inch- diameter Apr. (zinnia). Plants were irrigated extending vase life of nonsensitive (1160 mL) pots spaced at 12 · 12 inches. as needed with 100 mgÁL–1 N from species (Elgar et al., 1999; Kenza Linaria and poppy seedlings 20N–4.4P–16.6K fertilizer (Peter’s et al., 2000). were grown at 10 ± 1.1 °C night Professional 20–10–20). Dahlia stems The objective of this study was temperatures, with day temperatures were harvested from 12 Aug. to 12 to evaluate water type, concentrated averaging 24 ± 1.6 °C. Lupine seed- Sept. 2003, rudbeckia stems from 1 sucrose vase solutions, floral foam, lings were grown at 15 ± 1.2 °C night July to 26 July 2003, and zinnia stems commercial hydrators and holding temperatures, with day temperatures from 17 June to 12 July 2004. solutions, cold storage, and ethylene averaging 24 ± 1.5 °C. Trachelium Stems were harvested according sensitivity as components of the post- seedlings were grown at 15 ± 1.7 °C to criteria set for each species (Table harvest handling of seven specialty cut night temperatures, with day temper- 1); placed into buckets of tap water flowers. atures averaging 27 ± 1.6 °C. (pH 6.3–7.1; EC 0.18–0.23 dSÁm–1); Plants were irrigated as needed sorted into similar groups based on Materials and methods with 150 mgÁL–1 N from 20N–4.4P– stem length and diameter, flower bud CUT STEM PRODUCTION. ‘Lace 16.6K fertilizer (Peter’s Professional number and flower size, as appropri- Violet’ linaria, ‘Sunrise’ lupine, ‘Tempt- 20–10–20; Scott’s, Marysville, OH) ate for the species; re-cut; and sub- ress’ poppy, and ‘Jemmy Royal Pur- during the week and with unamended jected to appropriate experimental ple’ trachelium plants were grown in a tap water on the weekends. Linaria treatments. Stem length after recut- polyethylene-covered greenhouse us- stems were harvested from 8 March to ting was 30 cm for most species ing a peat-based commercial root sub- 2 Apr.