Exposure of bulbs of Easter Lily (Lilium longiflorum Thunb.) to a maximum of 2 μl ethylene/liter during vernalization delayed flowering by 5 to 7 days and decreased the number of flower buds. Ethylene exposure for 5 days at 21C after vernalization accelerated shoot emergence and flowering by up to 3 days. No floral or plant abnormalities were observed after bulb exposure to ethylene. Exposure to atmospheres with 0%, 0.5%, or 1% O2 at 21C for up to 2 weeks before or 10 days after vernalization did not “significantly impair subsequent bulb forcing. Storage in 1% 02 at 21C for 1 week before vernalization resulted in nearly one additional secondary bud initiated per plant. Exposure to up to 15% CO2 at 21C for up to 2 weeks before or 10 days after vernalization did not significantly impair subsequent forcing.

Lining of shipping cases with low-density polyethylene (PE) greatly reduced moisture loss from packing media and bulbs of Lilium longjlorum Thunb. `Nellie White' during shipping, handling, and case vernalization (CV). Three years of studies showed that use of PE liners accelerated floral sprout emergence above the growing medium, floral bud initiation, and flowering date. Effects of case lining became more pronounced as the initial water content of the spagnum peat packing was lowered. Case lining sometimes increased apical meristem diameters measured immediately after vernalization, or 2 or 4 weeks after bulb planting, but flower bud number was never significantly increased. Root growth during the first 4 weeks after planting was not affected by case lining. Bulb scale and basal plate water contents at planting were greater in lined than nonlined cases and when packed in peat of relatively high moisture content. Handling and vernalization of bulbs in PE-lined cases without a packing medium resulted in similar bulb forcing characteristics as in bulbs held in PE-lined cases packed with sphagnum peat.

Termination of fertilization 1 to 4 weeks before harvest of Euphorbia pulcherrima Wild. ‘Annette Hegg Dark Red’ resulted in decreased postharvest leaf abscission on nonsleeved plants. Termination 3 weeks before harvest had no effect on leaf drop while termination 4 weeks before harvest increased leaf drop of sleeved plants. Epinastic response to sleeving and cyathia drop were not influenced by fertilizer termination times. Medium analysis at harvest showed that increased time without fertilizer increased pH, decreased soluble salts concentration and individual nutrient levels. Foliar nutrient level differences at harvest were small.

The poststorage and post-shipping quality of Lilium longiflorum Thunb. ‘Nellie White’ plants sprayed with silver thiosulfate (STS) complex or phenidone was observed in a simulated interior environment. Bud abortion and foliar chlorosis increased while floral longevity declined with increasing storage period from 0 to 4 weeks in the dark at 2°C. One to 3 days of simulated, boxed shipment at 23° subsequent to 3 weeks storage at 2° further increased foliar chlorosis but did not influence bud abortion or floral longevity. Whole plant STS sprays (0.5 to 2.0 mM Ag) prior to harvest reduced storage-induced bud abortion and increased floral longevity, but did not reduce foliar chlorosis. Ethephon application to plants that had been stored for 3 weeks at 2° induced bud abortion and abnormal floral development. STS application (1.0 mM Ag) prior to storage reduced ethephon-induced disorders. Preharvest whole plant sprays of phenidone decreased bud abortion on stored and nonstored plants but did not influence floral longevity. Uptake of phenidone and STS through cut petioles enhanced ethylene production during opening of excised lily buds. Ethylene production increased while respiration declined during senescence of excised buds. STS did not reduce but did delay the peak of ethylene production during senescence of lily flowers. Chemical names used: 1-phenyl-3-pyrazolidone (phenidone); (2-chlorethyl)phosphonic acid (ethephon).

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