This study was conducted to understand the effect of different nutrient control method on the growth, cut-flower quality, root activity and fertilizer consumption. Single-node cutting rose `Versillia' was grown in aeroponics and DFT system and was irrigated with the nutrient solution of the Univ. of Seoul (NO3 -N 8.8, NH4 -N 0.67, P 2.0, K 4.8, Ca 4.0, Mg 2.0 me·L-1). Recirculated nutrient solution was managed by five different control method: macro- and micro-element control in aeroponic system (M&M); macroelement control in aeroponic system (M); nutrient solution supplement in aeroponic system (S); electrical conductivity (EC) control in aeroponic system (EC-A); EC control in deep flow technique system (EC-D). The mineral nutrient control method had significantly effected on the cut-flower quality. In the M&M and M, flower length, fresh weight and root activity were higher than those with other mineral nutrients control method. Although EC-A and EC-D could save total amount of fertilizer compared to M&M and M, the growth and quality of the rose with EC control system were lower than those with mineral nutrient control system. Therefore, these result suggest that EC control system is not economic method in a closed hydroponic system.
Eun Young Yang*, Keum Soon Park, Dong Soo Lee and Yong-Beom Lee
J.C. Vlahos and M. Papadimitriou
Ebenus cretica, Leguminosae, is a perennial bush endemic to the island of Crete, and produces attractive pinky red or purple flowers on 15-cm long racemes. To study the possibility of its use as a cut flower, cut inflorescences on 40-cm-long spikes were taken from plants grown outdoors in the farm of the Technological Educati Institute and used to determine the postharvest characteristics of Ebenus flowers. Without any postharvest treatments, the inflorescences held in water had an average life of about 7 days. A solution of 100 ppm 8-hydroxyquinone sulfate (HQS) in DI water, supplemented with 5% Ca(NO)3 increased vase life for 2 days and improved the water potential without affecting transpiration, whereas the addition of 2% or 5% sucrose decreased vase life by 1 or 2 days respectively. Pulsing with 0.2 mm STS for 2 h improved flower quality and vase life. Addition of 6-BAP (2 ppm) or GA3 (3 ppm) in the preservative solution did not affect flower quality or vase life compared to control. These results indicate that inflorescences of Ebenus cretica may be used as cut flowers; however, further research is required to determine their sensitivity to ethylene as well as its storage capabilities.
Philip E. Hammer, S.F. Yang, M.S. Reid and J.J. Marois
The effectiveness of fungistatic atmospheres for postharvest control of Botrytis cinerea Pers. infections on cut rose flowers (Rosa hybrids L.) was investigated. Storing cut `Sonia', `Royalty', and `Gold Rush' roses at 2.5C with 10% CO2 for 5 days, followed by 2 days of cold storage in air, reduced the number of B. cinerea lesions that developed on inoculated and noninoculated flower petals by 77% and 82%, respectively, compared to cold storage for 7 days in air. Higher CO2 concentrations and longer CO2 treatment times reduced disease severity further, but resulted in unacceptable leaf discoloration on some cultivars. No deleterious effects of CO2-enriched storage atmospheres on flower quality, weight gain, or vase life were observed. Storage at 2.5C for 7 days in 2 μl SO2/liter reduced B. cinerea infections on inoculated and noninoculated flowers by 53% and 43%, respectively. No deleterious effects on flower quality, weight gain, or vase life were observed. Higher SO2 levels reduced disease severity further, but caused bleaching of the petal margins and necrosis around leaf wounds.
Philip E. Hammer, Kathleen B. Evensen and W.J. Janisiewicz
Pyrrolnitrin, an antibiotic isolated from Pseudomonas cepacia, was used for postharvest control of B. cinerea infections on cut `Sonia' and `Royalty' rose flowers. Pyrrolnitrin was applied as a bud dip and followed by inoculation with B. cinerea conidia. Dip treatments of 12 to 200 mg·liter-1 pyrrolnitrin significantly reduced disease severity during storage at 2C and promoted post-storage fresh weight gain (an index of cut flower quality). No phytoxicity was observed on leaves or petals at concentrations of up to 200 mg/liter. Dip treatment with 100 mg/liter pyrrolnitrin reduced disease severity to <10% of that on control flowers and prevented post-storage flower rot. This level of disease control was comparable to that achieved with 1800 mg/liter vinclozolin.
Chi Won Lee, Benjamin Liang, Kenneth L. Goldsberry, Ralph R. Baker and Phillip L. Chapman
This study was carried out to determine the influences of planting date (June, July) and soil applications of Trichoderma harzianum (strain T-95) and a fungicide containing ethazole + thiophanate (BanrotR) on flower production of standard carnation cvs. Improved White and Tanga. The one-year production data showed that the fungicide treatment increased flower yield by 7.3% (33.5 flowers/m2) and 4.8% (23.3 flowers/m2) in Improved White and Tanga, respectively, for June planting. Improved White produced more flowers and fancy grades when planted in July as compared to June planting. Planting date did not influence either the yield or the flower quality in Tanga. The effectiveness of Trichoderma as a biological control agent on flower yield and quality was not evident. The patterns of weekly flower production for the two cultivars were determined and graphically illustrated.
K. Jacquemin Sullivan and C.C. Pasian
Cut-flower production of three snapdragon (Antirrhinum majus L.) cultivars (`Potomac Pink', `Winter White', and `Potomac Light Pink') in growing trays vs. ground beds was evaluated in five different plantings over a period of a year and a half. The experiments evaluated the quality of cut flowers from plants in ground beds or in small vs. large trays either raised or placed directly on the ground bed. The quality of flowering shoots was lower when plants were grown in raised trays rather than in on-ground trays or in ground beds, but other treatments did not affect quality consistently. Flowering shoot grade (a subjective quality indicator) correlated well (r = 0.8) with the ratio of shoot dryweight to shoot length (an objective quality indicator). Our results confirm that the flower quality of snapdragons grown on ground trays can equal that of those grown in ground beds.
Caroline H. Pearson-Mims and Virginia I. Lohr
Cut `Samantha' roses (Rosa hybrida L.) were placed in deionized water or a 20-mm Ca(NO3)2 pulsing solution for 72 hours. Flowers then were held in preservative solutions containing 0 or 4 mg fluoride/liter. Fresh weight gain, solution uptake, degree of flower opening, and flower longevity were reduced in the presence of fluoride in the holding solution. Visual symptoms of injury and reduced flower quality also were noted in treatments with fluoride. Pulsing improved fresh weight gain and degree of opening of flowers held in solutions containing fluoride. Pulsing also delayed the onset of visual symptoms of fluoride injury. Water uptake for flowers that were pulsed and exposed to fluoride was not different from uptake for flowers exposed to fluoride alone. Flower longevity for roses in all treatments was increased by using the calcium nitrate pulse, but pulsed flowers in fluoride did not survive as long as the control flowers.
Fisun G. Çelikel and Michael S. Reid
The respiration of flowers of stock [Matthiola incana (L.) R. Br.] had a Q10 of 6.9 between 0 and 10 °C. Simulated transport for 5 days resulted in marked reduction in the vase life of flowers transported at 10 °C and above. Flower opening, water uptake, and vase life of the flowers increased somewhat in a vase solution containing 50 ppm NaOCl, and considerably in a commercial preservative containing glucose and a bactericide. Exposure to exogenous ethylene resulted in rapid desiccation and abscission of the petals, effects that were prevented by pretreatment with 1-methylcyclopropene (1-MCP). Even in the absence of exogenous ethylene, the life of the flowers was significantly increased by inhibiting ethylene action using pretreatment with silver thiosulfate (STS) or 1-MCP. STS was more effective than 1-MCP in maintaining flower quality.
Apostolos A. Paralikas, J.C. Vlahos, M. Papadimitriou and K.A. Loulakakis
Ebenus cretica, Leguminosae, an endemic perennial bush of Crete, is being studied as a potential new cut flower crop. Forty-centimeter-long spikes with two to three inflorescences and six to eight compound leaves were harvested from 5-year-old plants grown from seed at the farm of the TEI, when 1/3 of the florets had opened, and were treated with various preservatives. Flower quality was evaluated morphologically combined with measurements of chlorophyll content in leaves and anthocyanin in petals. Without any postharvest treatments, inflorescences held in a solution of 100 ppm 8-hydroxyquinone sulfate (HQS) in DI water had an average vaselife of 6.8 days. Pulsing with 0.6 mM silver thiosulfate (STS) for 2 h extended vaselife up to 8.4 days. However, when ethephon was added in the solution, vaselife was significantly reduced, causing leaf yellowing and flower senescence, which suggests sensitivity to exogenous ethylene. A solution of 0.2% Ca(NO3)2 prolonged vaselife by 2.7 days, whereas higher concentrations resulted in flower discoloration and decreased flower quality. Sucrose solutions of 0.5%, 1%, 2%, and 4% had no positive effect on flower longevity. Furthermore, the higher concentrations caused leaf yellowing and petal discoloration decreasing vaselife and quality of flowers compared to control. Samples of inflorescences were taken every second day for chlorophyll (a and b) and anthocyanin measurements. The concentrations recorded were highest in the 0.2% Ca(NO3)2 treatment and were significantly correlated to flower longevity. Results indicate that Ebenus cretica may be used as a cut flower crop; however, due to the genetic variability of the Ebenus plants, a breeding line should be developed before the crop reaches the floricultural market.
Rebecca Kincaid* and Tracy Dougher
There has been an increasing interest in drought tolerant native flower species for Montana residential landscapes and roadsides. Ratibida columnifera is a drought tolerant, perennial wildflower that can be used in home gardens as well as on roadsides. However, there is no knowledge of how R. columnifera will respond to typical nitrogen fertilization in residential landscapes. Our objective was to determine the correct nitrogen application required for R. columnifera to acquire optimal growth and development. After germinating and transplanting R. columnifera seedlings, nitrogen treatments began with five groups containing six pots in each group. Pots were fertilized with 100 ml of ammonium nitrate at 0ppm N, 25 ppm N, 50 ppm N, 75 ppm N, or 100 ppm N at weekly intervals. All pots were fertilized with 100 mL of 50 ppm potassium phosphate. Three plants from each treatment were harvested 30 days after the start of fertilization treatments and underwent biomass evaluations of their fresh and dry weights. The remaining three pots from each treatment were evaluated at blooming for time to flowering, flower number, and flower quality. R. columnifera biomass at 30 days benefited from 25-50 ppm nitrogen, but did not increase biomass above 50 ppm. Flowering was affected at different levels than biomass and was delayed by high nitrogen.