Potted spring-flowering bulbs and bedding and garden plants collectively account for $1.97 billion (49%) of the total U.S. wholesale value of floriculture crops for the 15 top-producing states ( U.S. Department of Agriculture, 2011 ). These crops
William B. Miller, Neil S. Mattson, Xiaorong Xie, Danghui Xu, Christopher J. Currey, Kasey L. Clemens, Roberto G. Lopez, Michael Olrich and Erik S. Runkle
Kenneth R. Tourjee, James Harding and Thomas G. Byrne
The development of gerbera (Gerbera jamesonii H. Bolus ex. Hooker) as a floricultural crop is traced from its collection as a botanical novelty in South Africa to its establishment as a commercial crop in the 1930s. The origin of the cultivated germplasm, G. jamesonii and G. viridifolia (DC) Schultz- Bipontinus, is discussed, as well as breeding work that occurred in Europe and the United States. The contributions of the two species to the cultivated germplasm is unknown. Early breeding in Europe was conducted by RI. Lynch at the Cambridge Botanic Gardens in England, R. Adnet at La Rosarie in Antibes, France; and by C. Sprenger in Italy. In the United States, early work was done at estates in New Jersey by Herrington and Atkins, and by the commercial growers Jaenicke and the J.L. Childs' Seed Co. Establishing the cold hardiness of the crop for temperate climates was an early goal of horticulturists and breeders. Much of the cultivated germplasm can be traced to material that passed through Cambridge and Antibes.
Neil S. Mattson and W. Roland Leatherwood
genotypic differences in Si accumulation have been reported in rice ( Deren et al., 1992 ), this may be the first such report for floricultural crops. Differential uptake suggests that these cultivars may have functional homologs to Lsi1 , the gene
James E. Barrett, Carolyn A. Bartuska and Terril A. Nell
Experiments with' White Christmas' and `Carolyn Wharton' caladiums (Caladium × hortulanum Birdsey), croton (Codiaeum variegatum), brassaia (Brassaia actinophylla Endl.), `Annette Hegg Dark Red' poinsettia (Euphorbia pulcherrima Wind.), and `Super Elfin Red' and `Show Stopper' impatiens [Impatiens wallerana (L.) Hook.f.] determined effectiveness of paclobutrazol in solid spike form as compared to media drench applications for height control. Paclobutrazol drenches and spikes were effective for all crops tested, with a similar concentration response for all, except that drenches had greater efficacy than spikes on caladium. A reduced effect was observed when spikes were placed on the medium surface of `Super Elfin Red' impatiens, while placement in the middle of the pot or around the side was equally effective. These results indicate that the spike formulation of paclobutrazol has potential to provide adequate size control for floriculture crops with the possible exception of rapidly developing crops, such as caladiums. Chemical name used: (2RS, 3RS)-1-(4-chlorophenyl)-4,4-dimethyl-2-1,2,4-triazol-1-yl-) penten-3-ol (paclobutrazol).
Kristin L. Getter
; Miller and Armitage, 2002 ). Conclusions The effect of ADT on PBZ efficacy of these four floriculture crops was largely dependent on species. Of the species tested here, only geranium was impacted by ADT, PBZ, and their interaction. Growers should use the
Kristin L. Getter, Bridget K. Behe and Heidi Marie Wollaeger
to pay a price premium for floriculture crops grown using different pest management practices (grown using bee-friendly insect management practices, best insect management practices to protect pollinators, protective neonicotinoid insecticides, or
William R. Woodson
Lisa J. Skog*, Theo Blom, Wayne Brown, Dennis Murr and George Chu
Ozone treatment has many advantages for control of fungal diseases. There are no residue concerns, no registration is required, and it is non-specific, therefore potentially effective against a broad spectrum of pathogens. However, ozone is known to cause plant damage. There is little information available on either the ozone tolerance of floriculture crops or the levels required to kill plant pathogens under commercial conditions. Nine floriculture crops (begonia, petunia, Impatiens, Kalanchoe, pot roses, pot chrysanthemums, lilies, snapdragons and Alstroemeria) were subjected to increasing levels of ozone. Trials were conducted at 5 and 20 °C (90% to 95% RH) and ozone exposure was for 4 days for either 10 hours per day (simulating night treatment) or for 10 minutes every hour. Damage was assessed immediately after treatment and after an additional 3 days at room temperature in ozone-free air. Trials were terminated for the crop when an unacceptable level of damage was observed. Trials to determine the lethal dose for actively growing pathogens (Alternaria alternata, Alternaria zinniae and Botrytis cinerea) and fungal spores were conducted under identical conditions. Ozone tolerance varied with plant type and ranged between <0.2 and 3ppm. Generally, the crops surveyed were more susceptible to ozone damage at the low temperature. As a group, the bedding plants were the least tolerant. Fungal spores were killed at treatment levels between 0.8 and 2 ppm ozone. The actively growing fungal mycelium was still viable at 3 ppm ozone when the trial had to be terminated due to ozone-induced structural damage in the treatment chambers. Under the trial conditions, only the Kalanchoe would be able to tolerate the high levels of ozone required to kill the fungal spores.
Heidi M. Wollaeger, Kristin L. Getter and Bridget K. Behe
understand consumer perceptions and willingness to pay a price premium for floriculture crops grown using different pest management practices including: traditional, neonicotinoid-free, bee-friendly, or biological control pest management practices. We
Sophia Kamenidou and Todd Cavins
Silicon (Si) is a nonessential element that has proven to be a beneficial supplement to agricultural crops. In floriculture greenhouse production, soilless substrates have limited Si content and supplements may improve plant quality. The objective of this study was to determine Si sources, rates, and application methods to improve plant quality. Zinnia elegans `Oklahoma Formula Mix', Helianthus annuus `Ring of Fire', and Gerbera `Acapella' were provided potassium silicate (KSiO3) as a media incorporated flakes or weekly drench, sodium silicate (NaSiO3) as weekly foliar spray or ashed rice hulls. Zinnia and Helianthus Si levels were highest in leaf (0.5% to 1.7%), followed by flower (0.3-0.5%) and stem (0.2-0.4%) tissues. Gerbera accumulated lower amounts of Si compared to Zinnia and Helianthus with similar leaf and flower content values ranging from 0.4% to 0.6% with stem values 0.4% Si. Depending on source and rate, several horticultural traits were improved. Zinnia benefits included stem thickness, increase in flower diameter and stem erectness. Helianthus Si supplementation resulted in increased stem thickeness and flower diameter. However, phytotoxicity problems occurred with Si rates above 200 mg·L–1 (SiO2 applied as weekly potassium silicate drench). Gerbera stems thickened with KSiO3 and NaSiO3 applications, but NaSiO3 foliar sprays increased stem length, flower diameter and resulted in earlier flowering.