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Vegetatively propagated unrooted cuttings are typically imported to the United States from Central America. Death or damage of cuttings during shipping and propagation can be reduced if cuttings can be made more resistant to external forces, such as physical damage or pathogen infection. However, strategies to develop durable cuttings via treating stock plants have not been previously quantified in controlled studies. During the current study, mechanical strength of leaves and resistance to infection by Botrytis cinerea were evaluated after weekly applications of calcium chloride (CaCl₂) as a foliar spray to stock plants that delivered calcium (Ca) at the concentrations of 0, 400, or 800 mg·L⁻¹. A texture analyzer quantified the peak force required to fracture the leaf and the work of penetration,or area under the force–displacement curve, and these measurements were indicators of mechanical strength. For poinsettia (Euphorbia pulcherrima Willd. ex Klotzsch) cuttings at the time of harvest from the stock plant, work of penetration increased by 10% with the application of 800 mg·L⁻¹ Ca compared with the control, whereas peak force by 9%. For zonal geranium (Pelargonium ×hortorum Bailey), work of penetration increased 15% with the application of 800 mg·L⁻¹ Ca compared with the control. Calcium concentration in the leaves increased from 1.2% to 2.0% in geranium and from 1.0% to 1.6% in poinsettia with increasing application from 0 to 800 mg·L⁻¹ Ca. In poinsettia, disease incidence in response to inoculation with B. cinerea spores was 55% and 15% less with CaCl₂ applications compared with controls with water and surfactant, respectively, whereas CaCl₂ application to geranium did not affect disease incidence.

Vase life of ‘Karma Thalia’ dahlia (Dahlia ×hybrida), ‘Lace Violet’ linaria (Linaria maroccana), ‘Sunrise’ lupine (Lupinus hartwegii ssp. cruickshankii), ‘Temptress’ poppy (Papaver nudicaule), ‘Indian Summer’ rudbeckia (Rudbeckia ×hybrida), ‘Jemmy Royal Purple’ trachelium (Trachelium caeruleum), and ‘Benary's Giant Scarlet’ and ‘Sun Gold’ zinnias (Zinnia elegans) was determined after being subjected to postharvest handling procedures. Cut dahlia, lupine, poppy, rudbeckia, trachelium, and ‘Sun Gold’ and ‘Benary's Giant Scarlet’ zinnia flowers could be held in unamended tap or deionized (DI) water with no effect on vase life. Vase life of linaria was longest when placed in DI water with 8-hydroxyquinoline citrate 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. Floral foam or 2% or 4% sucrose had no effect on the consumer vase life of dahlia, lupine, rudbeckia, and poppy. Trachelium and rudbeckia did not tolerate a 20% sucrose treatment for 24 h, whereas linaria and ‘Benary's Giant Scarlet’ zinnia had a longer vase life with a 10% sucrose pulse than a water-only pulse. For trachelium, the longest (17.5 days) consumer vase life occurred when the Chrysal Professional 2 Processing solution (CP2) was used after pretreatment with DI water. Either of two commercial holding solutions, CP2 or Floralife Professional (FLP), similarly extended the vase life of linaria. The use of FLP or CP2 improved consumer vase life of dahlia, lupine, and poppy compared with DI water. Dahlia, trachelium, and 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. Lupine and trachelium were susceptible to 1 μL·L⁻¹ exogenous ethylene, which induced floret abscission in lupine and stopped floret opening in trachelium. 1-Methylcyclopropene and silver thiosulfate similarly suppressed the ethylene effect. Cut linaria, zinnia, dahlia, rudbeckia, and poppy flowers were unaffected by exogenous ethylene.

Pelargonium hortorum Bailey `Pinto Red' plants were grown with 220 mg·L⁻¹ N (20N-4.4P-16.6K) using hand (HD), microtube (MT), ebb-and-flow (EF), and capillary mat (CM) irrigation systems. At harvest, root balls were sliced into three equal regions: top, middle, and bottom. A negative correlation existed between root medium electrical conductivity (EC) and N concentration to root number such that the best root growth was obtained with low medium EC and N concentrations. EF root numbers were greatest in the middle region. The two subirrigation systems (EF and CM) had higher average root numbers than the two surface-irrigation systems (HD and MT). For all irrigation systems, root numbers were lowest in the top region. In general, less difference in medium soluble salt and N concentrations existed between regions for surface-irrigated than for subirrigated root balls. Soluble salt concentration was lowest in the bottom and middle regions of EF and the bottom region of MT and CM. For subirrigation, the highest medium soluble salt and N concentration was in the top region. For all systems, pH was lowest in the bottom region. Plant growth for all irrigation systems was similar. EF and MT systems required the least water and EF resulted in the least runoff volume.

Consumer flower-color preferences are of interest to market researchers, plant producers, and retailers because this information can help them to anticipate accurately the sales product mix. Our objective was to determine consumer bract-color preferences for 47 poinsettia (Euphorbia pulcherrima Willd. ex Klotzsch) cultivars. Visitors (124) to the Franklin Park Conservatory in Columbus, Ohio, rated `Sonora', a red cultivar, highest (4.6 of 5.0) of any cultivar. Nine of ten highest rated cultivars were red. We compared the ratings of poinsettia buyers with those of nonpoinsettia buyers and found only one difference: nonpoinsettia buyers rated `Jingle Bells III', a marble cultivar, higher (4.3) than poinsettia buyers (3.8). We also compared consumers who had purchased a red poinsettia to those who had purchased nonred colors and found that red poinsettia buyers rated `Sonora' higher (4.9) than nonred poinsettia buyers (4.5). Men rated `Red Elegance' higher (3.7) than women (3.3), whereas women rated `Freedom White' higher (3.1) than men (2.4). We found few differences between men and women, buyers and nonbuyers, and nonred buyers and red buyers, which may indicate a relatively homogeneous market that does not greatly differentiate among poinsettia bract color.

Sunflower (Helianthus annuus) has potential as a potted flowering plant due to short crop time, ease of propagation, and attractive flowers but postharvest life is short and plants can grow too tall. Days from sowing to anthesis differed significantly among six sunflower cultivars and ranged from 52 days for `Big Smile' to 86 days for `Elf' and `Pacino.' Height ranged from 6.0 inches (15.2 cm) for `Big Smile' to 14.9 inches (37.8 cm) for `Pacino', postproduction life ranged from 10 days for `Elf' and `Pacino' to 15 days for `Big Smile', and postproduction chlorosis ratings (1 to 5, with 5 the least) ranged from 5.0 for `Teddy Bear' to 4.4 for `Big Smile' after 5 days and 4.2 for `Teddy Bear' to 3.1 for `Sunspot' after 10 days. Promalin (a gibberellin and benzyladenine mixture) applied at 62.5 to 500 ppm (mg·L^-1) was not commercially useful in extending postproduction life. Increasing pot size from 4 to 6 inches (10 to 15 cm) in diameter decreased postproduction life and plants in 5-inch-diameter (13 cm) pots were tallest. Pots with three plants flowered more quickly than those with one or five plants and pots with five plants had 1 day shorter postharvest life than those with one or three pots. All cultivars were facultative short-day plants, except for `Sundance Kid', which was day neutral. Storing potted sunflowers at 41 °F (5 °C) for 1 week did not reduce postproduction life, which was 11 to 12 d; however, 2 weeks of cold storage resulted in foliar damage. Three cultivars were found to be most suitable for pot production, `Elf', `Pacino' and `Teddy Bear', with one or three plants per 6-inch pot and sprayed with daminozide (B-Nine) at 8,000 ppm, or drenched with paclobutrazol (Bonzi) at 2 mg/pot (a.i.) (28,350 mg = 1.0 oz).

Plant growth regulators (PGRs) are used to control excessive plant growth in potted crops to improve quality and compactness for shipping and display. Pineapple lily (Eucomis sp.), a recent introduction to the potted crop market, can have excessive foliage growth and inflorescence height making the use of PGRs desirable. Bulbs of ‘Leia’ pineapple lily were forced in the greenhouse and drenched at leaf whorl emergence with three PGRs at five different concentrations: 1) flurprimidol (0.25, 0.5, 1.0, 2.0, and 4.0 mg per 6.5-inch pot), 2) uniconazole (0.25, 0.5, 1.0, 2.0, and 4.0 mg/pot), or 3) paclobutrazol (0.5, 1.0, 2.0, 4.0 and 8.0 mg/pot) and an untreated control. As concentration increased, days to anthesis increased and foliage height decreased for each PGR. Paclobutrazol (4.0 and 8.0 mg/pot), uniconazole (4.0 mg/pot), and flurprimidol (2.0 and 4.0 mg/pot) treatments resulted in excessive stunting with none of the plants being marketable. Flurprimidol had the greatest influence on plant growth among all the PGRs. Acceptable concentrations for each PGR are paclobutrazol at 0.5 to 2.0 mg/pot, uniconazole at 0.25 to 2.0 mg/pot, and flurprimidol at 0.5 to 1.0 mg/pot based on percentage of marketable plants and foliage and inflorescence height suppression without excessively increasing the number of days to anthesis.

In the United States and Canada, there has been an increase in the demand for local specialty cut flowers and a corresponding increase in production. To assess the needs of the industry, we electronically surveyed 1098 cut flower producers and handlers in the United States and Canada regarding their current cut flower production and postharvest problems, and customer issues. We received a total of 210 responses, resulting in a 19% response rate. The results showed that the main production problem was insect management; crop timing was the second most important problem and disease management was the third. Crop timing encompasses a range of related issues such as determining the correct harvest stage, harvest windows that are too short, flowering all at once, or lack of control when the crop is ready to harvest. The main postharvest problems were temperature management, hydration, and flower food management. Timing and stem length were the two most mentioned species-specific production issues, with each one listed by 10% or more of the respondents for eight of the total 31 species. Regarding on-farm postharvest handling, hydration and vase life were the two most mentioned issues; they were reported for five and three species, respectively. For postharvest during storage and transport, damage and hydration were the most common issues; these were listed for three species each. The most commonly mentioned customer complaints were vase life and shattering, which were reported for six and two species, respectively. These results will allow researchers and businesses to focus on the major cut flower production and postharvest issues and on crops that are most in need of improvement in North America.

Effects of harvest time (morning, noon, or afternoon) on water uptake, fresh weight changes, termination symptoms, leaf relative water content (LRWC), carbohydrate status, and vase life of cut ‘ABC Purple’ lisianthus (Eustoma grandiflorum Salisb.), ‘Double Eagle’ African Gold Coin Series marigold (Tagetes erecta L.), and ‘Deep Red’ Benary’s Giant Series zinnia (Zinnia elegans Jacq.) were studied. For stems of lisianthus harvested and then stored in the dark with the basal ends in water for 2 weeks at 3 ± 1 °C, those harvested at noon (1200 hr to 1300 hr) or in the afternoon (1700 hr to 1800 hr) had longer vase life compared with stems harvested in the morning (0700 hr to 0800 hr). However, stems of lisianthus evaluated without storage had no differences in vase life. Stems of marigold harvested in the afternoon had longer vase life than morning- or noon-harvested stems. Time of harvest had no effect on cut flower longevity of zinnia. However, vase life was considerably shorter for stems of all species when tested after 2 weeks storage compared with freshly harvested stems. Stems of zinnia harvested at noon had lower LRWC than morning- or afternoon-harvested stems. Marigold stems harvested in the afternoon and evaluated without storage had lowest LRWC on Day 7 of vase life. Harvest time or storage did not influence LRWC of lisianthus. Stems of marigold and lisianthus harvested at noon or in the afternoon had higher levels of carbohydrates compared with morning-harvested stems, whereas freshly harvested stems had higher concentrations of glucose and sucrose, which decreased during storage or the vase period. Sucrose concentrations varied more significantly among various tissues than other sugars presumably as a result of translocation during vase life. In summary, carbohydrate status of stems harvested at different times of the day varied greatly and affected postharvest longevity of cut marigold and lisianthus, but not zinnia.

The germination responses of wild blue indigo [Baptisia australis (L.) R. Br.], purple coneflower [Echinacea purpurea (L.) Moench.], Maximilian sunflower (Helianthus maximiliani Schrad.), spike goldenrod (Solidago petiolaris Ait.), and Missouri ironweed (Vernonia missurica Raf.) seeds after 0, 2, 4, 6, 8, or 10 weeks of stratification at 5C were investigated. Seed viability was determined using triphenyl tetrazolium chloride staining and germination based on the percentage of viable seeds. Germination percentage (GP) increased in all five species as weeks of stratification increased. Days to first germination and germination range (days from first to last germinating seed) decreased with increasing weeks of stratification, but the effect beyond 4 to 6 weeks was minimal. The number of weeks of stratification for maximum GP was 4 for purple coneflower, 6 for Maximilian sunflower, 8 for Missouri ironweed, and 10 for wild blue indigo and spike goldenrod.

`Gutbier V-14 Glory' poinsettias (Euphorbia pulcherrima Willd. Ex. Klotzsch) grown with ebb-and-flow irrigation used the least amount of water and produced the least runoff, and plants grown with capillary mats used the greatest amount of water and produced the most runoff, compared to microtube and hand-watering systems. The maximum amount of water retained by the pots and media was greatest for the microtube and ebb-and-flow systems and became progressively lower for the hand-watering and capillary mat systems. The media and leachate electrical conductivity from plants grown with subirrigation systems was higher than those grown with top irrigation. For the two top-irrigation systems (microtube and hand-watering), plants grown with 250 mg N/liter from a 20N-4.4P-16.6K water-soluble fertilizer had greater leaf, stem, and total dry weights than those grown with 175 mg N/liter. The two subirrigation systems (ebb-and-flow and capillary mat) produced plants that were taller and had greater leaf, stem, and total dry weights when grown with 175 than with 250 mg N/liter. The higher fertilizer concentration led to increased N, P, Fe, and Mn concentration in the foliage. Nitrogen concentration was higher in top-irrigated plants than in subirrigated plants. The ebb-and-flow system produced the greatest total dry weight per liter of water applied and per liter of runoff; capillary mat watering was the least efficient in regard to water applied and runoff.