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Kenneth W. Mudge, Joseph P. Lardner, and Katherine L. Eckenrode

The objective of this study was to determine the feasibility of CO2 enrichment and optimal radiation level for accelerating the rooting and growth of micropropagated Kalmia latifolia cuttings during the Stage IV acclimation period. Inch long microcuttings of the Kalmia cultivars `Elf' and `Carousel' shipped from a commercial micropropagation laboratory, were stuck in flats of peat, and place in a fogging chamber constructed to allow for the simultaneous experimental variation of CO2 level and either radiation level or photoperiod. Treatments consisted of a complete factorial arrangement of 2 levels of CO2 (ambient and 1200 ppm) and 3 levels of radiation (30, 98, and 158 μmoles/m2/sec). The experiment was repeated 6 times. For `Carousel' CO2 enrichment stimulated both shoot and root growth and either the high or medium light level was optimal depending on the experiment. CO2 enrichment also stimulated growth of `Elf' but results were less consistent from experiment to experiment. Similar experiments are in progress with Amelanchier and Lilac microcuttings.

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Rida A. Shibli and M.A.L. Smith

Ohelo (V. pahalae Skottsb.) and bilberry (V. myrtillus L.) shoots were regenerated via direct organogenesis from whole leaves and leaf sections and also from hypocotyl explants of bilberry. Explants preincubated for 1 to 2 weeks in darkness yielded ≈75% regeneration frequencies and the highest number of regenerating shoots/explant on TDZ-supplemented media (0.9 to 2.7 μm). When 2iP or zeatin were substituted as the cytokinin source, frequencies of regeneration and shoot productivity were significantly lower. Explants held under constant illumination (no dark pretreatment) had significantly lower regeneration frequencies in all tested cytokinin-supplemented media. 2,4-D stimulated callus formation, but did not support regeneration from vegetative explants. Cells from callus and suspension cultures did not exhibit regeneration in any of the media that supported organogenesis from leaves. Regenerants were successfully micropropagated, although callus formation caused by zeatin and high 2iP levels interfered with shoot proliferation. Zeatin induced hyperhydricity in shoots from both species, but more severely in ohelo. Ex vitro rooting after treatment with 4.9 μm IBA or 5.4 μm NAA was 95% and 60% successful for bilberry and ohelo, respectively, and plants were readily acclimatized after an interval in a fog chamber. Bilberry microshoots also rooted in vitro in the absence of growth regulator treatment. Chemical names used: 1H-indole-3-butanoic acid (IBA); N-(3-methyl-2-butenyl)-1-H-purine-6-amine (2iP); 6-furfurylaminopurine (kinetin); 1-naphthaleneacetic acid (NAA); thidiazuron=1-phenyl-3-(1,2,3-thiadiazio-5-yl)urea (TDZ); 2,4-dichlorophenoxyacetic acid (2,4-D); 6-(4-hydroxy-3-methylbut-2-enylamino) purine (zeatin).

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Clint Hoffmann, Brad Fritz, Dan Martin, Ryan Atwood, Tim Hurner, Mark Ledebuhr, Matt Tandy, John L. Jackson, and Gail Wisler

London Fog model 18–20 sprayer (London Fog, Long Lake, MN) ( Table 2 ), initial testing with water and water plus NIS with the machine operating at 2810 and 1850 rpm, respectively, and a rate of 1.9 L·min −1 produced D V0.5 of 57.8 ± 13.2 and 85.9 ± 1

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Dalong Zhang, Yuping Liu, Yang Li, Lijie Qin, Jun Li, and Fei Xu

-VPD compartment, humidification was controlled using a fogging system (spray pressure, 2–6 MPa; droplet size, 25.8–46.2 µm) with a binary fluid mist nozzle. Spraying was activated automatically when the greenhouse VPD exceeded 1.5 KPa, which is the recommend value

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Allen V. Barker

, desert fog, runoff, soil salinity, and oases. The effects of sandy land and rocky land are contrasted with respect to effects on the desert environment. Short presentations are made for hot deserts and cold deserts and of the effects of fires on deserts

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Jonathan Foster, Stephanie Burnett, and Lois Stack

ensure proper fog containment. The tops and bottoms of all systems were left open for ventilation and drainage. Irrigation was provided using a capacitance sensor-automated fog system that was a variation of the sensor-automated drip irrigation system

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Simone da Costa Mello, Jéssika Angelotti-Mendonça, Lucas Baiochi Riboldi, Luigi Tancredi Campo Dall’Orto, and Eduardo Suguino

°42′30″S, long. 47°38′00″W). Intermittent fog system maintained the relative humidity around 70%. The relative humidity was controlled automatically by sensors that were connected to a datalogger (CR10x; Campbell Scientific, Logan, UT), which continuously

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Richard J. Henny, Jianjun Chen, and Terri A. Mellich

without intermittent mist or fog to maintain high humidity (maximum irradiance of 80 μmol·m −2 ·s −1 ) in a shaded greenhouse (maximum irradiance of 125 μmol·m −2 ·s −1 ) and under natural photoperiod within a temperature range of 15 to 34 °C. In each test

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Carlos De la Cuadra, Alexis K. Vidal, Patricia Peñaloza, Leví Mansur, and Carlos Huenchuleo

experiences cloud cover and fog almost all year, little and highly variable rainfall from year to year, mean monthly temperatures from 10 to 20 °C, and a mean daily temperature oscillation of 7.5 °C. According to Antonioletti et al. (1972) , the seasonality

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Kamal Aberkani, Xiuming Hao, Damien de Halleux, Martine Dorais, Stephen Vineberg, and André Gosselin

fogging systems have been used to prevent plant heat stress during the day. In fact, shading is one of the conventional and familiar techniques used by growers to decrease solar radiation and reduce air and leaf temperatures ( Sandri et al., 2003 ). Many