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  • Author or Editor: Roy A. Larson x
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Abstract

Once upon a time, in a far-off land, a member of the genus Gallus was walking through a forest populated with trees of the genus Quercus. Suddenly, something fell and struck this creature on the head. The creature was quite cowardly—you might even call it “chicken”—and it began to run and cry, “The sky is falling, the sky is falling, and I must tell the king”. On the way to the palace, she encountered other feathered members, whose names are really inappropriate to use in a sophisticated presidential address—names such as Henny Penny, Cocky Locky, Goosey Loosey, and Turkey Lurkey—and she told them the news and they joined her in her rush to see the king. They then met a rather devious character, who said he would show them a short-cut to the palace, but he really intended to have a sumptuous dinner of low-cholesterol, low-protein poultry products. Chicken Little forever remained a pessimist and never again went into the oak forest without an umbrella.

Open Access
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Plastic products have revolutionized commercial floriculture. Even plastic flowers have caused a new marketing consideration because they are quite competitive with the marketing of live material. Plastic pots are used widely because they are lightweight, attractive, and relatively inexpensive. Plastic flats and trays have been readily accepted by the consumer, and were instrumental in the development of plug culture. Major components of automatic watering systems are made of plastic, and much of the plumbing practiced in commercial floriculture is done with plastic pipe and fittings. Plastic foams are used in floral arrangements, growing media, and propagation cubes or strips. Plastic is used to make steam-sterilization covers, shading material for the manipulation of both light intensity and photoperiod, and mulches or ground covers to help control weeds. Very large quantities of plastic are used in commercial floriculture, and recent landfill restrictions have necessitated procedures for recycling. Recycling procedures are known, but logistics and economics of recycling have not been resolved completely.

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Abstract

2,3-Dihydro-5-6-diphenyl-l,4-oxanthin (UNI-P293), was used to determine its effectiveness as a disbudding agent of Chrysanthemum morifolium cv. May Shoesmith. Concentrations of 0.5, 0.75 and 1.0% were applied on the 18th, 21st and 24th short day (SD). The optimum concentration on the 18th SD was 0.5% and 1.00% on the 21st SD. There was no difference among concentration levels on the 24th SD. Flower size and date of anthesis were not adversely affected when manual disbudding was used as a supplement to chemical treatment, but smaller flowers and delayed anthesis usually occurred when only the chemical was used for disbudding. All treated plants were shorter than untreated plants.

Open Access

Abstract

Three gibberellins; GA3, GA4, GA7; and abscisic acid (ABA) from the shoot tips of greenhouse grown ‘Gloria’ azaleas, Rhododendron sp.L., were tentatively identified using column chromatography, gas-liquid chromatography, and Rumex leaf senesence bioassay. Growth regulators were quantitatively estimated biweekly from 6 weeks after shoot tip removal until anthesis.

GA3 levels remained nominal for the normal commercial treatment until after plants were returned to 19°C from the 9° cooler. Endogenous GA3 levels then peaked at 0.6 μg/bud at anthesis. GA4 levels remained fairly constant for all treatments and times at 0.1 μg/bud. GA7 levels remained fairly constant below 2 μg/bud except in the cold-treated plants when endogenous GA7 levels peaked at 0.6 μg/bud at the time that plants were removed from the cooler.

ABA levels were similar until 24 wks. from pinch when the levels dropped to undetectable levels in cold-treated plants and increased in treatments not given a cold treatment by peaking at 0.1 μg/bud at 28 wks. from pinch.

Of the commercially available gibberellins that were monitored, GA7 seemed to be the best treatment for chemically overcoming flower bud dormancy in azalea.

Open Access

Abstract

Periodic shaking increased the resistance of potted poinsettia (Euphorbia pulcherrima Klotzsch ex. Willd., cv. Annette Hegg Diva) plants to mechanically induced leaf epinasty, but this resistance was lost within 24 hours of discontinuing the shaking. Bending petioles, not their reorientation in the gravitational field, caused increased ethylene production by excised petioles. Foliar sprays containing 40 μm cycloheximide, which were applied 24 hours before the plants were sleeved for 24 hours, completely prevented mechanically induced leaf epinasty, but were phytotoxic to the bracts.

Open Access

Abstract

Flower bud development was ascertained by biweekly dissections of shoot apices, until bud color was apparent. Satisfactory results were obtained when plants were given 3 weeks at 2 or 9°C, followed by 3 applications of GA3 at 250 ppm. The results were less satisfactory when attempts were made to completely substitute GA3 for the cool temp requirement to break dormancy.

Open Access

Abstract

Vegetative growth, flower bud initiation, and early flower development of ‘Red American Beauty’ azaleas were enhanced at temp of 30-26°, 26-22°, 30-22°, 26-18°, and 22-18°C. Earliest flowering occurred following temp of 22-18°, 22-14°, and 18-14°C. The 4°C difference between day and night temp resulted in plants superior in quality to those exposed to an 8° difference.

Open Access

Abstract

Foliar sprays of either 10 mM aminoethoxyvinylglycine or 3 mM silver ions applied 24 hours before potted poinsettia plants (Euphorbia pulcherrima Klotzsch ex. Willd., cv. Annette Hegg Diva) were sleeved for 24 hours, significantly reduced the development of leaf epinasty after removal of the sleeves.

Open Access