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Abstract
Rapid clonal propagation of Alnus glutinosa was achieved in vitro using lateral buds excised from greenhouse grown, juvenile stock plants. Multiple shoot development occurred in 50% of the cultures after the first subculture (7–8 weeks after initial explanting) using a low salt, woody plant medium containing 1 μM 6-benzylaminopurine (BA). Microshoots were removed from pro-liferating tissues and rooted in a conventional potting medium under high humidity prior to establishment in the greenhouse.
Abstract
Cut carnation flowers shipped from California by air occasionally arrive at eastern markets in a senescent condition with losses greater in the warm autumn months. CO2 and C2H4 production by the flowers has a pattern similar to that of climacteric-class fruits, with senescence correlated with a rise in release of the gases.
Cut carnation flowers show an enormous increase in respiratory heat with increasing temperature: 89 BTU/ton/hour at 0°C versus 14,718 at 50°C. In C2H4-free air, the flowers tolerate elevated temperatures but their vase life is reduced. Their sensitivity to C2H4 increases dramatically with increasing temperature, with the threshold concentration partially depending on prior stresses on the flowers.
Flowers in containers exposed to direct sunlight developed temperatures as high as 49.5°C. Air temperatures inside containers shipped via jet aircraft were as high as 35°C. The C2H4 concentrations in the containers may reach 10.5 ppm.
The remarkable resistance of cut carnation flowers to mechanical injury, combined with their low metabolic rates at low temperatures, makes refrigerated surface shipments feasible and perhaps economically desirable. Their resistance to injury seems related to their light weight, the damping action of the petals, and the lack of phenolase or readily oxidizable phenolic compounds in the petals.
Abstract
The longevity and quality of flowers experimentally shipped from California to Maryland by refrigerated trucks for 4–5 days were comparable with or better than simulated air-shipped flowers when properly handled. Flowers shipped by air are usually not refrigerated in transit. Best results with ‘White Sim’ carnations (Dianthus caryophyllus L.), ‘Albatross’ standard chrysanthemums (Chrysanthemum morifolium Ramat) and ‘Cara Mia’ roses (Rosa hybrida L.) were obtained when flowers were pretreated after harvest with a chemical solution for 16 hours, precooled prior to shipment and shipped in insulated boxes. Preshipment pulsing of carnations and chrysanthemums increased longevity and bloom diameter. Pulsing of ‘Cara Mia’ roses extended longevity and prevented “bent neck.” Chrysanthemums and roses benefited from ice in the box even with good refrigeration but carnations did not. Carnations and chrysanthemums cut at a tight bud stage suffered much less than open blooms from heat stress conditions during handling of flowers.
Abstract
Excessive temperatures recorded within flower boxes on transcontinental refrigerated trucks were avoided by using an integrated system of preshipment cooling with forced-air, standardized containers and appropriate stacking pattern. The longevity and quality of flowers shipped from California to Florida by refrigerated trucks were comparable to or better than that of air-shipped flowers. Preshipment conditioning treatments did not improve flower longevity of shipped roses, carnations or gladioli. Preconditioning chrysanthemum stems in AgNo3 solution eliminated the need to recut stems after shipment. Carnations and gladioli handled dry lasted as long as conditioned flowers. Floral preservative used on roses and carnations after shipping had a more positive affect on longevity than any other handling treatment.