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Wagner A. Vendrame, Virginia S. Carvalho, José M.M. Dias, and Ian Maguire

) supplemented with 0.4 M sucrose (pH 5.7). The high concentration of PVS2 prevents ice crystallization during cryopreservation. Treatments consisted of pollinia left in PVS2 either at room temperature (27 ± 2 °C) or precooled in ice (0 °C) for 1, 2, 3, or 4 h

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Ludwika Kawa and August A. De Hertogh

Shoot apical meristems of Freesia ×hybrida Klatt `Rossini' reached the reproductive state after 3 weeks of precooling at 9C. Meristems isolated after 6 and 7 weeks of precooling showed the development of the initial four florets of the inflorescence.

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Christopher B. Cerveny and William B. Miller

potential for 1-MCP application immediately before planting has not been investigated and is the subject of this research. Materials and Methods Pre-cooled bulbs (16 weeks at 5 °C) of Tulipa gesneriana L. ‘Markant’ were treated with flow

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Natalia R. Dolce, Ricardo D. Medina, Luis A. Mroginski, and Hebe Y. Rey

study, the ultralow storage of fresh pollinia was feasible without any desiccation, cryoprotection, or precooling treatment before placing directly into an ultra freezer (−70 °C) or immersing in LN (−196 °C). This is probably due to the low initial MC

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Paul W. Teague and Tina G. Teague

Several common methods of post harvest handling and pre-cooling for fresh market bunched greens (turnips, smooth and curly mustard, and collards) were evaluated. Six treatments were evaluated where greens were rehydrated and precooled using different combinations of hydrocooling, slush ice, and shoveled ice with three rehydration methods (hydrocooling, water drench, and water floating). Product temperatures were monitored and overall quality ratings were made after seven days in cold storage. Product quality after seven days was best with hydrocooling and insignificant differences in quality were recorded whether in-box ice was shoveled or slush ice. Turnips were most sensitive to degradation if precooled inadequately. Collards were the least sensitive. Economic analysis was completed using labor and ice cost differentials of selected packing and cooling methods to calculate product volume levels required to amortize relatively high costs of the hydrocooler, slush icer, and ice machine. Extremely large volume is required to fully amortize equipment acquisition costs based on labor cost savings alone. Greater cost savings per box, when comparing the cost of purchased ice to homemade ice, resulted in much lower volume requirements for full amortization. The results indicate that a producer with limited capital would benefit the most economically from acquiring an ice machine. The greatest quality benefit is gained from precooling with the hydrocooler.

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Amy L. Enfield and James E. Faust

Poinsettia `Prestige', New Guinea impatiens `Sonic White', and petunia `Improved Charlie' cuttings were harvested from stock plants, weighed, placed in glass jars, and placed at 10, 15, 20, or 25 °C. Carbon dioxide accumulation was measured and used to determine respiration rates at 2, 6, 10, 24, and 48 hours. Vegetative cuttings have very high initial respiration rates that quickly decline over time. At 2 hours, respiration rates at 25 °C were 5.4-, 2.4-, and 4.3-fold higher vs. 10 °C in poinsettia, New Guinea impatiens, and petunia, respectively. By 48 hours, there was little difference in respiration rates. In a second experiment, poinsettia `Prestige' cuttings were pre-cooled at 10 °C for 0, 3, 6, 12, or 24 hours before being transferred to 20 °C. Respiration rates were measured at 0, 2, 6, 10, 24, 48, and 72 hours in the 20 °C environment. Regardless of pre-cooling duration, respiration rates increased when cuttings were transferred from 10 to 20 °C. Respiration rates of cuttings pre-cooled for 3, 6, or 12 hours were not significantly different from cuttings maintained at constant 20 °C. However, after transfer, cuttings pre-cooled for 24 hours had a respiration rate significantly lower than cuttings maintained at constant 20 °C, but by 72 hours, there were no significant differences.

Open access

R. A. Cohen and J. R. Hicks

Abstract

Broccoli, cauliflower, cucumber, pepper, and muskmelon were displayed (a) in direct sun, (b) in the sun under intermittent mist, (c) in the shade under intermittent mist, (d) in the shade, and (e) on ice at a simulated roadside market for 1-day intervals. In addition, some produce was precooled prior to display. Either ice or the shade under mist treatment was effective in reducing weight loss during display, particularly for broccoli and cauliflower. The prime factor involved in differences in weight loss among crops or between cultivars of the same crop seemed to be the surface area to volume ratio. Precooling prior to display slightly reduced the weight loss for cucumbers and muskmelons but had no effect on the other commodities.

Open access

P. Allen Hammer and Douglas A. Hopper

Abstract

Regression analysis of the height of ‘Ace’ and ‘Nellie White’ over time was used to develop prediction equations of Easter lily height (Lilium longiflorum Thunb.). Case-cooled (cooled before planting) and controlled-temperature-forced (cooled following planting) bulbs that received 6 or 7 weeks of cooling required different equations to predict height. Case-cooled bulbs precooled 6 weeks required 7.4 and 6.1 weeks of forcing for shoots to reach 50% of their final height for ‘Nellie White’ and ‘Ace’, respectively. Controlled-temperature-forced bulbs precooled 6 weeks required 11.1 and 9.0 weeks of forcing for shoots to reach 50% of their final height for ‘Nellie White’ and ‘Ace’, respectively. The equations provide a baseline of lily elongation over time.

Open access

B. Tjia, H. Heafy, and J. Buxton

Abstract

Foliar application of 5% and 10% alkaryl polyoxyethylene glycol (X–77) surfactant to greenhouse forced pre-cooled ‘Georgia’ Easter lilies resulted in flower bud abortion and shorter plants. No phytotoxic effects were observed following application of 5% X–77 and only slight curving of young leaves were noted with 10% X–77 when applied to plants after 60 or more leaves had unfolded. There was no decrease in leaf number or damage to leaf area.

Open access

A. A. De Hertogh

Abstract

Exercises are described to familiarize horticultural students with the ‘Standard Forcing’ of potted tulips, hyacinths, daffodils, Iris reticulata, Crocus and grape hyacinths as well as cut tulips and daffodils. Procedures are outlined for ‘Special Precooling’ of tulips and Dutch iris as cut flowers. In addition, a simplified list of readily available cultivars of the spring-flowering bulbs covered is provided. The exercises utilize Valentine’s Day as the marketing holiday.