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Neil Anderson, Peter Ascher, Esther Gesick, Lee Klossner, Neal Eash, Vincent Fritz, James Hebel, Stephen Poppe, Judith Reith-Rozelle, Roger Wagner, Susan Jacobson, David Wildung, and Patricia Johnson

.O. Anderson and P.D. Ascher, unpublished data, 1990). The new plant size was recognized as having market potential; the 90-287 hybrids, which displayed this phenotype, flowered the first year from seed, were winter hardy, and were selected for continued

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Dariusz P. Malinowski, Robert S. Brown, and William E. Pinchak

Winter-hardy hibiscuses are herbaceous perennials in the mallow (Malvaceae) family that belong to six species native to the United States: H. coccineus Walter (scarlet rose mallow), H. dasycalyx S.F Blake and Shiller (Neches River rose mallow

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Dariusz P. Malinowski, Robert S. Brown, and William E. Pinchak

Winter-hardy hibiscuses are herbaceous, shrub-like perennials in the mallow (Malvaceae) family that belong to six species native to the United States and southern Canada ( Lawton, 2004 ; Winters, 1970 ). They grow naturally in marshy habitats

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Becky R. Hughes and Adam Dale

Four winter-hardy strawberry selections and three cultivars where planted in northern Ontario in 2003 in a split-split plot trial where half the rows were mulched and half were left uncovered for the winter. Within each split plot, half the rows were sprayed for tarnished plant bugs and half were not. Yield and tarnish plant bug damage data was collected for two picking years. Two selections maintained their yields in the unmulched plots compared to the mulched plots. Yield for one of these selections was higher in the unmulched plots the first picking year and equal to the mulched plots in the second year. The remaining cultivars and selections produced less when not mulched for the winter. Except for the two selections that maintained their yields in the unmulched plots, plots where straw was applied for the winter had less tarnish plant bug damage. When the plots were sprayed for tarnish plant bugs, damage was reduced for most but not all selections and cultivars.

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Cecil T. Pounders

Winter-hardy hibiscuses are herbaceous perennials that regenerate from root buds each spring in USDA hardiness zones 5 through 9. Colloquially known as Rose Mallows, the most recent taxonomic revision ( Blanchard, 1976 ) recognizes five species

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Neville P. Arnold, Michael R. Binns, Daniel C. Cloutier, Nayana N. Barthakur, and Raymond Pellerin

Auxins, medium salt concentrations, and their interactive effects on rooting of two winter-hardy roses (Rosa kordesii Wulff `John Franklin' and `Champlain') and two hybrid teas (Rosa hybrida `John Paul II' and `Landora') were studied. The auxins (in mg·liter–1) IAA (0, 0.3, 1.5, 3.0, 6.0, or 15.0), IBA (0, 0.1, 0.2, 0.5, 1.0, or 3.0), and NAA (0, 0.1, 0.2, 0.5, 1.0, or 3.0) each were combined factorially with modified Murashige and Skoog (MS) medium (1/4, 1/2, 3/4, and full MS concentrations) and were tested for optimal rooting response. `John Franklin', `John Paul II', and `Landora' rooted well with low or no auxin and medium to high salt concentrations. Optimum rooting for `Champlain' was achieved with high IAA and low salts or with intermediate IBA and NAA concentrations and low to medium salts. The interactive effects of auxins and medium salts for `Champlain' showed that as salt concentration increased, the amount of IBA or NAA required for optimal rooting also increased. The effects of auxins and medium concentrations on root counts per shoot were similar to those for percent rooting. Adding auxin to the medium reduced root length for all cultivars, but salt concentration had a minimal effect. Roots generally were shortest at the highest IBA and NAA concentrations. Salt concentration had little effect on root length. Chemical names used: 1H-indole-3-acetic acid (IAA); 4-(3-indolyl)-butyric acid (IBA); α-naphthaleneacetic acid (NAA).

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Ian S. Ogilvie, Neville P. Arnold, and Claude Richer

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Fanyi Shen, Rongfu Gao, Wenji Liu, Wenjie Zhang, and Qi Zhao

It is known that the redistribution of water and the formation of dispersed water units appears to be a prerequisite for deep supercooling. A concentration of the cell solute results from the migration of water during extracelullar freezing and lowers the temperature of homogeneous nucleation, but we are convinced that nucleation of ice within cells may be initiated by a heterogeneous mechanism, except we consider a small spherical cave, the water can freeze on the wall of this cave. We are also convinced that the solid walls of the capillary exert an external potential on the water molecules, causing the shift of the triple point of the confined fluids. Based on Fletcher's work for spherical particle, we have gotten the formula of critical free energy in the process of heterogeneous nucleation of water in a small spherical cave. This presentation introduces the theoretical background and counts the drop of temperature in heterogeneous nucleation. Then, putting two actions (depression of triple point and process of heterogeneous nucleation) together, we have calculated the freezing point. Sometimes it is lower than –38 °C. Some phenomena can be explained by using this theory: 1) Water is at the tension status, which means that it wets plant tissue, so the triple point (melting point) of tissue water can be lowered. 2) The redistribution of water, formation of dispersed water units, and dry region preventing ice from propagating, all allow heterogeneous nucleation, then the two actions can be synthesized and the water would lead to deep supercooling. If the barriers were destroyed, heterogeneous nucleation and deep supercooling would certainly be lost. 3) This theory is only suited to rigid wall of small cave, so we understand why cell wall rigidity has been shown to affect freezing characteristics. Project 39870234 supported by National Nature Science Foundation.

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Shahrokh Khanizadeh, Yvon Groleau, Rong Tsao, Raymond Yang, Inteaz Alli, Robert Prange, and Robert Demoy

‘Diva’ is the first scab-resistant apple released, specifically for northern climates, for cider and ice cider production and fresh market. It is very winter-hardy (lowest temperature –20 to –35 °C, Zones 4 to 5), has an excellent shelf life