Flowering Pot Research Articles

Role of abscisic acid in perianth senescence of daffodil (Narcissus pseudonarcissus"Dutch Master").

Daffodil (Narcissus pseudonarcissus L. 'Dutch Master') flowers detached at the base of their ovaries and held with their cut ends in 10-100 microM abscisic acid (ABA) senesced prematurely. Symptoms of the ABA treatment included water-soaking of the tepals and early collapse of the corona. No water-soaking was seen in tepals of flowers held in water. Instead, the tepals of these flowers dried. The ABA content increased in tepals of the potted flowers as they senesced. The rise in tepal ABA content coincided with the appearance of visual signs of senescence. When the flowers were cut and placed in water, a treatment that accelerated their senescence, the increase in ABA occurred earlier. Exogenously applied ABA enhanced the premature accumulation of senescence-associated transcripts in the tepals. Their ABA-mediated induction was not prevented when the flowers were pre-treated with 1-methylcyclopropene, an inhibitor of ethylene action, indicating that ABA induced the transcripts independently of ethylene. The transcripts accumulated in opened control flowers before the rise in endogenous ABA. Attempts to extend floral longevity by using putative inhibitors of ABA biosynthesis [tungstate, fluridone (applied as Sonar((R))) and 1,1-dimethyl-4-(phenylsulphonyl)semicarbazide (DPSS)] were unsuccessful. However, inclusion of 100 microM gibberellic acid (GA(3)) in the vase solution reduced the senescence-inducing effects of 50 microM ABA suggesting a possible mechanism for in-vivo control of senescence.

Prelude and Fugue, in Minors

Prelude and Fugue, in Minors Lesmana Lim PRELUDE The first thing you notice about the Shriner's Hospital for Children is the vast expanse of handicapped spaces in the parking area. It immediately imparts a sense of grim pragmatism to an edifice built upon the most optimistic of ideas-that children who need special medical care should be able to get it for free. The handicap signs form a single column stretching into the distance, a long chain ofstern metal posts, a sturdy phalanx set to defend the choicest spots from the lucky ones who still enjoy a full range ofmotion. We park in the back of the lot. I was ten yeats old die fitst time I came to the hospital. Chicago was a wonderful oddity to me then, a schizophrenic metropolis. Chicago was the Latino quarter, where wholesalers gave us coffee and bagels and my dad bought exotic goods for our familygrocery store. Or itwas the alien mystique ofChinatown, with its beautifully strange architecture and herbal boutiques and pigs and ducks hanging in butcher's windows. Other times it was Michigan Avenue, bustling with fashion and movement, buildings taller dian God. It seemed as if the city was constantly disappearing and reappearing, a series of urban Brigadoons, each unaware ofthe existence ofother Chicagos. It was any other city, as it would look shone dirough a prism, each component expanded and more than the sum of its parts, every hue distinct and luminous. The Shriner's Hospital was not a color I had seen before. I was accustomed to the conventional strangenesses ofChinatown or the wholesale district, but here was a thoroughly unimportant-looking building crawling with old men in peculiar hats. The red fez is a great symbol ofthe Ancient Arabic Order of the Nobles of the Mystic Shrine, distinguishing it from the other Masonic orders. It's considered a sign of nobility and philanthropy, proudly worn by members for over a hundred years. The Shriner's take their fez seriously. I, however, could not. Nothing in the entire history ofsecret playground clubs and special handshakes could rival the absurdity ofthese men wearing those 200} George B. Lawson Essay Award, SecondPlace 5 6 LESMANA LIM hats, which looked not unlike an overturned KFC bucket lovingly perched upon your grandfather's head. This wasn't MichiganAvenue. I couldn't decide what part ofChicago I had gotten into. The confusion only deepened when I saw the hospital commons. It was a spacious, well-decorated area, designed to take full advantage of natural light. A generous number of trees and plants brightened the atmosphere, along with a few well-kept potted flowers. There was a black, baby grand piano with a bright tone in one corner, and two colorful play areas for smaller children in others. And everywhere were wheelchairs, prosthetics, splints and braces connected to children of all sorts. It was like stumbling into some postmodern incarnation of Leonardo's workshop, or John Cage composing the human form, an etude ofirregular symmetries and mechanical aides. I didn't know what to think about it, this menagerie of toddlers, but it scared me in ways that left me ashamed. The whole enterprise carried such an air ofdashed expectations, offailure. I sat on a bench, pulled out my Walkman and turned up Gershwin as loud as it could go. When it came time for my appointment, a thin young man brought me to a small lab where they recorded my height and weight, snapped some Polaroids and took a series ofx-rays. Afterwards he led me to a clean, white office where a doctor was waiting. She had a kind face and we small-talked for a bit. Then she asked me, "Do you know why you're visiting us today?" I said no, that my mother only told me that we would be going to Chicago, and that we were going to see a doctor. I'd had shots before and gotten my blood taken once or twice, and it hadn't been all diat bad. "Okay," she said. "Let me just tell you diat there's nothing wrong with you, and that you're a perfecdy healthy boy. You've...

갯쑥부쟁이(Heteropappus hispidus (Thunb.))의 감마방사선 감수성과 M1 세대 형질변동 특징

제주도에서 자생하는 갯쑥부쟁이(Heteropappus hispidus (Thunb.))에 감마선을 10, 20, 40, 80, 120, 160, 200, 300, 400 Gy 수준으로 나누어서 조사한 뒤 발아율 및 발아 30일 후의 본엽 출현율, <TEX>$LD_{50}$</TEX>, 본엽길이, 줄기부분의 안토시아닌 색소 형성 유무, 생육 60일 후의 로젯형 엽, multi-shoot 형성율, 초장, 개화 결실률 등의 주요 양적형질들을 생존개체를 대상으로 실시하였다. 120Gy 까지의 발아율은 88.5%로 대조구와 큰 차이를 보이지 않았으나 160Gy 이상에서부터는 급격히 감소하여 치사선량(<TEX>$LD_{50}$</TEX>)은 160 Gy 범위 정도였다. 또한, 본엽 출현율과 그 길이는 조사선량이 높아질수록 억제되었다. 안토시아닌 색소 형성은 조사선량이 높을수록 대조구 2%에서 30%로 높아졌으며 로젯형도 고선량 처리구에서 발생하였다. Multi-shooting은 80Gy 이상일 때부터 나타났으며 multi-shooting을 형성하는 개체들은 초장은 짧고 줄기는 가늘게 다발형으로 자라는 특성이 있어서 만일 형질이 고정된다면 화분 관상용 개체로 선발하기에 적합하였다. 특히, 조사선량이 증가됨에 따라서 안토시아닌 색소 형성, 로젯형 개체, multi-shoot등의 개체가 많이 출현되었는데 이는 돌연변이 유기의 선발지표가 될 수 있을 것으로 보인다. The seeds of naturally growing Heteropappus hispidus (Thunb.) were treated by nine different doses (0, 10, 20, 40, 80, 120, 160, 200, 300, 400 Gy) of gamma rays to investigate their germination rate and to quantity the characteristics of their germinated plants as like as leaf appearance and length, the formation rate of anthocyanin color in stem 30 days after germination, the formation rate of rosette leaf and multi-shoot, the flowering and seed-bearing, and shoot length. The germination rate at least up to 120Gy was not greatly affected but was rapidly decreased at over 160Gy. It seemed that lethal dose (<TEX>$LD_{50}$</TEX>) of germination was 160Gy. The leaf appearance and growth was also inhibited, but the formation rate of anthocyanin color in the flower stem was enhanced up to 30% with dose. The rosette plants were observed in plants irradiated with higher than 40Gy. Multi-shoots were developed over 80Gy. For a short shoot length and bundle of thin stem, it was considered that they can be selected as the potential pot flower plants, through genetic fixation. In particular, it was suggested that the formation of anthocyanin color in flower stem, rosette and multi-shoot plants induced by the high dose of gamma rays could be utilized as the morphological markers for the mutant selection of Heteropappus hispidus (Thunb.).

IN VITRO AND EX VITRO ROOTING AND PLANTLET ACCLIMATIZATION IN NERIUM OLEANDER

Oleander (Nerium oleander L.) is cultivated recently as a flowering pot plant and therefore abundant propagation plant material for commercial use is of great importance. In this study an effort was undertaken to investigate microcutting rooting in vitro and ex vitro and also acclimatization of young microplants. A single white flower clone of oleander was used for the experiments. Microshoots derived from in vitro stock cultures were used as microcuttings and placed for rooting in vitro or ex vitro. For in vitro rooting, the microcuttings were placed in WPM supplemented with IAA or NAA in various concentrations (0, 0.5, 1 or 2 pM). The best rooting was achieved with 2 pM NAA (23%). For ex vitro rooting, the microcuttings were first dipped in various concentrations (0, 0.13, 0.25 or 0.5 g l -1 ) of K-IBA and then were planted in perlite and kept in a fog system with relative humidity adjusted to 96-99%. Rooting was up to 70% with 0.5 g l -1 K-IBA. After rooting in vitro or ex vitro, the young plantlets were transplanted in pots and placed for hardening in a fog system with initial relative humidity at 95%, which then was decreased gradually to 80% in two weeks. The plantlets in the fog system were either under direct sunlight or under 50% shading provided by a net which lasted for 1 week and was removed afterwards. The transplanting losses for those rooted in vitro for both treatments were less than 5%, whereas no losses were noticed in those plantlets derived from ex vitro rooting.

EFFECT OF CULTIVAR, TIMING, GROWTH RETARDANTS, POTTING TYPE ON POTTED SUNFLOWERS PRODUCTION

Flowering pot plants represent one of the most interesting and promising typologies of ornamental productions, and frequently new species or products are selected for marketing. The use of sunflower as flowering pot plant, thought quite unusual for this species, could represent a powerful innovation, also in view of the positive trend shown in the last years by the production of sunflower as cut flower. On the other hand, as for any new product, there is a lack of information about the cultivation technique and the appropriate technology for getting best results in producing high quality potted sunflower. The aim of this work was to expand our knowledge on the cultural requirements of Helianthus annuus L. when grown as flowering pot plant and to characterise four genotypes (‘Big Smile’, ‘Pacino’, ‘Sunspot’ and ‘Teddy Bear’) selected for pot cultivation, by evaluating growth and ornamental parameters. We investigated the effect of different sowing periods (early spring, mid spring, late spring), container size (12 or 16 cm diameter), product typology (single or multiple plant per pot) and growth retardants (paclobutrazol and flurprimidol) on plant height and diameter, and on blooming period and ornamental characteristics of the flower. Results have shown that early sowing induces precocious blooming and reduced plant size in all tested genotypes with respect to late sowing date. Also container size affected plant growth, in particular plants grown in larger pots showed more compact habitus and a slight earliness in blooming. Growing multiple plants per pot resulted in a reduced size of each single plant, but the aesthetic value of the whole pot was increased. Our experiments indicated that the four genotypes tested, gave best results if treated with growth retardants which not only reduce plant height, but also increase plant uniformity. Between the two compounds tested, pacrobutrazol (used as a soil drench) was more effective then flurprimidol (used as foliar spray) in reducing size, without negative effects on crop quality.

Consumer Purchases of Campanula carpatica Jacq. 'Blue Clips' in Selected Supermarket Floral Departments as an Indoor Flowering Potted Plant

Four-inch (10.2-cm) potted floweringCampanula carpatica Jacq. 'Blue Clips' (campanula) traditional herbaceous perennials, were sold in floral departments of three retail supermarket chain stores from 5 May through 20 May and 16 June through 1 July 2000. The intent was to determine whether repositioning campanula as a “new” indoor flowering potted plant would add to total floral department sales or detract from sales of more traditional flowering potted plants. Unit sales for all 4- and 4.5-inch (10.2- and 11.3-cm) flowering potted plants stocked in three supermarket floral departments were recorded weekly and compared with unit sales from three stores where campanula were not sold (control). Unit sales for campanula were similar to those of traditional indoor flowering potted plants frequently stocked in floral departments. Statistical analysis showed that mean unit sales of traditional potted flowering plants for stores that did and did not stock campanula were similar. Therefore, adding campanula to the flowering potted plant mix did not detract from or jeopardize sales of similar indoor flowering potted plants.

Carbon balance and ethylene in the postharvest life of flowering hibiscus

The display life of potted flowering Hibiscus rosa-sinensis L. plants (held in a simulated interior environment) was terminated by depletion of their carbohydrate reserves, as determined by reduction in dry matter content of roots, stems, leaves, buds, and flowers. The substantial dry matter content of the short-lived flowers (0.2 g for singles, 0.6 g for doubles) was only partially recaptured when the flowers senesced. There was considerable variance in the low light compensation points for different hibiscus species and cultivars. Although the death of hibiscus flowers appears to be coordinated by ethylene, inhibition of ethylene action by treating the flowers with silver thiosulfate (STS) or 1-methylcyclopropene (1-MCP) had only a modest effect in extending flower life. Strategies for developing cultivars with improved display performance are discussed. © 2002 Elsevier Science B.V. All rights reserved.

SCALE-DEPENDENT EFFECTS OF LANDSCAPE CONTEXT ON THREE POLLINATOR GUILDS

Most ecological processes and interactions depend on scales much larger than a single habitat, and therefore it is important to link spatial patterns and ecological processes at a landscape scale. Here, we analyzed the effects of landscape context on the distribution of bees (Hymenoptera: Apoidea) at multiple spatial scales with respect to the following hypotheses: (1) Local abundance and diversity of bees increase with increasing proportion of the surrounding seminatural habitats. (2) Solitary wild bees, bumble bees, and honey bees respond to landscape context at different spatial scales. We selected 15 landscape sectors and determined the percentage of seminatural habitats and the diversity of habitat types at eight spatial scales (radius 250-3000 m) by field inspections and analyses of vegetation maps using two Geographic Information Systems. The percentage of semi- natural habitats varied between 1.4% and 28%. In the center of each landscape sector a patch of potted flowering plants (four perennial and two annual species) was placed in the same habitat type, a grassy field margin adjacent to cereal fields. In all, 865 wild bee individuals and 467 honey bees were observed and an additional 475 individuals were caught for species identification. Species richness and abundance of solitary wild bees showed a close positive correlation with the percentage of seminatural habitats at small scales up to 750 m, whereas bumble bees and honey bees did not respond to landscape context at these scales. In contrast, honey bees were correlated with landscape context at large scales. The densities of flower-visiting honey bees even increased with decreasing proportion of seminatural habitats at a radius of 3000 m. We are not aware of any empirical studies showing contrasting foraging patterns related to landscape context at different spatial scales. We conclude (1) that local landscape destruction affects solitary wild bees more than social bees, possibly changing mutualistic plant-pollinator and competitive wild bees- honey bees interactions and (2) that only analyses of multiple spatial scales may detect the importance of the landscape context for local pollinator communities.

Production and Postproduction Studies with Potted Sunflowers

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).

The Planning of Optimum Use of Bench Space for Potted Flower Production in a Newly Constructed Greenhouse

The Planning of Optimum Use of Bench Space for Potted Flower Production in a Newly Constructed Greenhouse

Efficacy of inhibitors of ethylene binding in improvement of the postharvest characteristics of potted flowering plants

Pre-treatment of potted plants of Campanula carpatica cultivars Dark Blue and Blue Clips and Schlumbergera truncata cultivar Dark Marie with the volatile ethylene binding inhibitor 1-methylcyclopropene (1-MCP) inhibited the effects of exogenous ethylene (bud abscission and wilting of flowers). In an ethylene-free simulated interior environment, display life of the 1-MCP treated plants was unaffected (Campanula) or slightly greater (Schlumbergera) than that of the controls, although not as good as that of plants pre-treated with the anionic silver thiosulfate complex (STS). Differences in effects of both blockers of ethylene binding sites are discussed.

INDIGENOUS PLECTRANTHUS (LAMIACEAE) FROM SOUTH AFRICA AS NEW FLOWERING POT PLANTS

Plectranthus L’ Herit (Spurflowers) is a group of soft herbaceous plants, some with unusually beautiful tubular flowers in blue, violet, white and pink. They grow naturally in the subtropical south-eastern parts of South Africa as forest-floor plants and flowering times peak in autumn. Other salient qualities are easy cultivation and propagation, using stem cuttings; semi-drought tolerance and requirement for semi-shade. In South Africa Plectranthus spp. are widely used outdoors as indigenous bedding plants and groundcovers. A few species of this horticulturally neglected genus are used internationally as commercial foliage pot plants, with no or little breeding improvement. However the first distinctive varieties of flowering pot plants have been developed in South Africa over the past ten years. Species were found to hybridize with difficulty and the resulting interspecific hybrids are almost invariably seed sterile. In our breeding programme we focus on developing a wide variety of compact plants with large and floriferous flower types and beautiful foliage. Improved foliage characters include texture (pleasant to touch and sight), shape (attractively rounded leaves), colour (silver-veined, variegated, underside red-tinted) and smell (pleasantly herbal typical of the mint family). A range of natural colours have been selected for and some selections now have the largest flowers in the genus. Product development focuses on flowering pot plants but also include hanging basket plants and floriferous outdoors plants for semi-shaded situations. The new series of hybrid Plectranthus are introduced under the Trademark ‘Blue Angels’. Research and development are done by a group of specialist nurseries in Australia, Europe, Japan, U.S.A. and South Africa. This includes breeding, technical development, propagation / marketing and specialist administration, all by separate companies. Plant Breeders’ Rights have been applied for.

Alternaria alternata Flower Blight of Zinnia acerosa in Texas.

Zinnia acerosa (D.C.) Gray, is a Southwest native flowering plant frequently observed in the Trans-Pecos desert and desert grasslands of Arizona, Texas, and New Mexico. The plant is valued for producing an abundance of distinctive 2.0 cm diameter white flowers on greenish and sparsely leaved stems. Selections of Z. acerosa from West Texas are under evaluation as a water conserving plant species for use in arid landscapes of the Southwest. During April through June, Z. acerosa plants in TAMU, Dallas field plots were observed with small, brown flower spots that enlarged to include whole petals, causing conspicuous flower blighting. Microscopic examination of lesions from infected flower blossoms demonstrated the presence of short beaked, cylindrical spores near the smaller lesions on flower petals. Isolations from symptomatic flower petals consistently yielded cultures of an Alternaria sp. with long chains of conidia. Typical conidia contained 3 to 5 transverse walls and 1 to 2 longitudinal walls and measured 43 μm length by 15 μm width. The fungus was identified as A. alternata (Fries) Keissler consistent with the description in Ellis (1). Pathogenicity tests were conducted on plants maintained on a greenhouse bench by spraying spore suspensions obtained from 16-day-old A. alternata cultures on potato-dextrose agar. Inoculations produced light brown lesions on blossoms typical of field disease symptoms of the disease. This disease is important as a flower blight, however, infections on the leaves are also apparent but limited. Outbreaks of the disease are frequently observed during periods of rainfall during the summer months. This is the first report of Alternaria alternata causing a floral blight on Z. acerosa.

Evaluation of Disease Resistance among 57 Cultivars of Zinnia

Fifty-seven cultivars of zinnia (Zinnia elegans Jacq.) were studied for 17 weeks to determine their resistance to alternaria blight (Alternaria zinniae Pape), powdery mildew (Erysiphe cichoracearum DC ex Merat) and bacterial leaf &amp; flower spot [Xanthomonas campestris pv. zinniae (syn. X. nigromaculans f. sp. zinniae Hopkins &amp; Dowson)]. A disease severity scale was used to determine acceptability for landscape use. At week 4, all cultivars were acceptable. At week 10, eleven cultivars were acceptable. At week 17, all cultivars were unacceptable. Ten cultivars had been killed by one or more pathogens by week 17. Only two cultivars showed any tolerance to any disease (powdery mildew) at week 17.

259 Effect of Photoperiod on Growth and Flowering of Ornamental Ginger Species

Gingers are tropical perennials from the Zingiberaceae family with attractive long-lived flowers that can be grown as potted plants in subtropical and temperate zones under protected conditions. Development of production practices for this new flowering pot crop is essential for optimum plant growth. The effect of photoperiod on growth and flowering was evaluated on Curcuma gracillima, C. cordata, C. alismatifolia, C. petiolata `Emperor', Curcuma `Chang Mai dwarf', Siphonichilus decora, and S. kirkii. Plants were grown under daylengths of 8, 12, 16, and 20 h. Plant height, number of new leaves, number of shoots, and leaf area were larger for plants growing under an extended daylength (16- and 20-h photo-period) than for plants under 8 and 12 h. Plants grown under an 8-h daylength approached dormancy sooner than those growing under 12, 16, or 20 h of light, and no flowering occurred.

Method for Using Images from a Color Digital Camera to Estimate Flower Number

In many plants, flowering is conspicuous in the field, but enumerating flowers is labor intensive, especially when flowers need to be counted on a daily basis. Frequent trips into plot areas and the physical contact with the plants can result in mechanical damage to plants, which can affect results. The objectives of this work were to develop methods using color digital images to estimate the numbers of flowers present in a scene captured in a digital image and to do all of the processing in a fully automated mode that would allow the counting of flowers in large numbers of images. Images of lesquerella [Lesquerella fendleri (Gray) Wats.] flowers were made using a color digital camera of field plots during the 1996 to 1997 growing season. An automated system to identify all of the pixels in an image that were flowers and to count the number of flower spots in an image was developed. Processing time for individual images was 3.5 min compared with a minimum of 45 min for manual counts. The automated methods produced results that were highly correlated with the number of flowers in an image as counted by hand. Results of the automated methods accurately tracked the temporal changes in flower number. Multiple counts of the same plants were made by the automated methods without damage to either plants that were counted or the plot. This method has the potential to be used to predict harvest dates from peak flowering, to track the response of flowering to environmental conditions, and to evaluate the effects of cultural practices on flowering.

Effect of thidiazuron on bud development of Cymbidium sinense Willd in vitro

Seed-derived rhizomes of Cymbidium sinense Willdwere able to initiate shoot buds in the presence of0.01--1 mg/l thidiazuron (TDZ). However, TDZ retardedrhizome proliferation. The regenerated shoot budswhich had been cultured on basal medium with asupplement of 0.5 mg/l 1-naphthalene acetic acid (NAA)and 1 g/l active charcoal were able to form 10 cmplantlets within four months. Plantlets weretransplanted to sphagnum moss and cultured on a mistbench for six months and then planted into soil-filledpots and maintained in the greenhouse, where they grewwell. In the 2nd year, 9.1% of the potted plants borenormal flowers. In the 3rd year, each of them produced5--6 shoots about 43 cm in height and about 20 roots;73% of the potted plants flowered normally.

Two New Hosts for Poinsettia Mosaic Virus.

Poinsettia mosaic virus (PnMV), a possible member of the genus Tymovirus, commonly infects the potted flower crop Euphorbia pulcherrima Willd. ex Klotzsch (1). Two new host species for this virus were identified during grafting experiments with E. pulcherrima and other Euphorbia spp. E. cornastra (Dressler) A. Radcliffe-Smith was reciprocally grafted with PnMV-positive E. pulcherrima cv. Eckespoint Lilo. PnMV was detected by double antibody sandwich-enzyme-linked immunosorbent assay (DAS-ELISA) in E. cornastra leaves directly below the graft union 4 weeks after grafting. Infection was not fully systemic 6 weeks after grafting when screened by DAS-ELISA with antibodies specific to PnMV (DSMZ, Braunschweig, Germany). The symptomless infection in E. cornastra persisted in cuttings from grafted plants after a 1-year observation period. E. bubalina Boiss. anatomy differs from that of E. pulcherrima. The two species did not produce a viable graft union. However, in an experiment with two attempted graftings, the E. pulcherrima scions remained turgid for 14 to 18 days. As a result of one grafting, the E. bubalina rootstock tested positive for PnMV. The virus induced a mild mosaic in E. bubalina, but no reduction in growth. To confirm virus presence in E. cornastra and E. bubalina, both DAS-ELISA and immunosorbent electron microscopy were used. Non-grafted controls remained PnMV negative. PnMV was re-isolated from both species by sap inoculation to Nicotiana benthamiana. E. coulescens Haw., E. xylophyllides Brogn. ex Lem., E. marlothiana N. E. Br., and Ricinus communis L. were not infected by PnMV after similar grafting attempts. Reference: (1) A. A. Brunt et al., eds. 1996. Viruses of Plants. CAB Int., Wallingford, UK.

`Florida Pink' and `Florida Light Blue'—Semi-dwarf Heat-tolerant Cultivars of Lisianthus

Additional index words. high temperature, rosette, potted flowering plants, Eustoma grandiflorum, Gentianaceae, plant breeding between UF8-21 and ‘Mermaid Blue’) (Fig. 1B). ‘Blue Lisa’ was chosen for its early flowering and dwarf characteristics. UF8-21 was selected after three generations of selfpollination of ‘Blue Poppy’-2, and ‘Mermaid Blue’ was chosen for its lower branching, dwarf characteristics. Growing conditions used to select seedlings for resistance to heat-induced rosetting during development of heat tolerant parents included: 1) production during summer months under greenhouse conditions at day temperatures ≤35 °C, 2) exposure of 3to 4-week-old seedlings to 28 °C for 4 weeks for initial selections in early generations, and 3) exposure of 17-d-old seedlings to 31 °C for 5 weeks for selection of final parents used in F1 hybrids.

Effects of Plant Growth Regulators Applied as Sprays or Media Drenches on Forcing of Dutch-grown Bleeding Heart as a Flowering Potted Plant

Two experiments were conducted to determine the effects of applied ancymidol, chlormequat, daminozide, paclobutrazol, and uniconazole on early spring (March) and late (May) spring forcing of Dutch-grown Bleeding Heart [Dicentra spectabilis (L.) Lem.] as a flowering pot plant. Most of the plant growth regulator (PGR) treatments delayed flowering, however, the average time to flower after planting was from 17 to 21 days for untreated plants and delays were only 3 to 6 days with PGR treatments. Thus, the effect is not important commercially. Acceptable plant quality and height control not only at flowering but also 14 days later was obtained with two sprays of 3000 mg·L-1 (ppm) daminozide or two sprays of 50 mg·L-1 paclobutrazol. Uniconazole reduced total plant height, however, because the inflorescence did not elongate, plant quality was greatly reduced. Most ancymidol sprays were phytotoxic producing a chlorosis of the leaf margins. Media drenches of ancymidol or chlormequat did not control total plant height. Sprays and media drenches of ancymidol, daminozide, paclobutrazol, and uniconazole produced plants with a very deep green leaf color, but chlormequat did not. The total number of shoots per tuberous root, the number of shoots with flowers, and stem strength were not significantly affected by PGR treatments. If the tuberous roots have been properly cold treated, they initiate growth rapidly after planting. Thus, the first PGR spray must be applied immediately after shoot growth is initiated, which was 6 to 8 days after planting, followed by a second spray 5 days later. Two applications are necessary because of uneven shoot emergence and growth from the tuberous roots.