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Gregory A. Endress, Anton G. Endress, and Louis R. Iverson

Differential responses of species to environmental stress may interfere with restoration of prairie ecosystems or change community structure. The impact of increasing atmospheric ozone (O3) concentrations and/or low water on the growth of Andropogon gerardii Vitm. (big bluestem) and Sorghastrum nutans (L.) Nash (indian grass), two common warm-season native grasses, and Setaria faberi Herrm. (giant foxtail), a vigorous annual weed species, were studied in replacement series. Giant foxtail grew better than either big bluestem or indian grass under all tested conditions. The leaf areas of all three species were primarily controlled by water availability. Big bluestem and indian grass accumulated biomass equally well under high water availability, but with low water, indian grass accumulated more biomass than did bluestem. Three-way analysis of variance showed biomass, leaf area, and leaf number differed among species; low water was significant in all cases except for indian grass leaf area; and the O3 effect was significant only in the case of foxtail biomass. The interaction of O3 concentration and low water was significant only for indian grass biomass and leaf number; the interaction of species combination and low water was significant only for big bluestem leaf area and biomass. Relative yield calculations indicated that under conditions of elevated O3 and low water, big bluestem was the least competitive, while indian grass was most competitive. Intraspecific competition was common, each species apparently utilizing the environment in different ways. The results also suggest that giant foxtail at a low relative density may be used as a nurse species in prairie restorations as growth of big bluestem and indian grass were improved when in mixtures with foxtail.

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Hongyi Zhang, William R. Graves, and Alden M. Townsend

We determined transpiration rate, survival, and rooting of unmisted, softwood cuttings of `Autumn Flame' red maple (Acer rubrum L.) and `Indian Summer' Freeman maple (Acer ×freemanii E. Murray). Effects of perlite at 24, 30, and 33 °C were assessed to determine whether responses of cuttings would be consistent with cultivar differences in resistance to root-zone heat previously shown with whole plants. During 7 d, cutting fresh mass increased by ≈20% at all temperatures for `Autumn Flame' red maple, but fresh mass of `Indian Summer' Freeman maple decreased by 17% and 21% at 30 and 33 °C, respectively. The percentage of cuttings of `Indian Summer' that were alive decreased over time and with increasing temperature. Transpiration rate decreased during the first half of the treatment period and then increased to ≈1.1 and 0.3 mmol·m-2·s-1 for `Autumn Flame' and `Indian Summer', respectively. Mean rooting percentages over temperatures for `Autumn Flame' and `Indian Summer' were 69 % and 16%, respectively. Mean rooting percentages at 24, 30, and 33 °C over both cultivars were 74%, 29%, and 25%, respectively. Over temperatures, mean root count per cutting was 41 and seven, and mean root dry mass per cutting was 4.9 and 0.4 mg, for `Autumn Flame' and `Indian Summer', respectively. Use of subirrigation without mist to root stem cuttings was more successful for `Autumn Flame' than for `Indian Summer'. Temperature × cultivar interactions for cutting fresh mass and the percentage of cuttings remaining alive during treatment were consistent with previous evidence that whole plants of `Autumn Flame' are more heat resistant than plants of `Indian Summer'. Mass and survival of stem cuttings during propagation in heated rooting medium may serve as tools for screening for whole-plant heat resistance among maple genotypes.

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Gina M. Angelella, Laura Stange, Holly L. Scoggins, and Megan E. O’Rourke

(Michx.) Greene, plains coreopsis– Coreopsis tinctoria Nutt., and indian blanket– Gaillardia pulchella Foug.], annual or biennial (blackeyed Susan– Rudbeckia hirta L.), and perennial forbs [lanceleaf coreopsis– Coreopsis lanceolata L., purple

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John McCallum, Susan Thomson, Meeghan Pither-Joyce, Fernand Kenel, Andrew Clarke, and Michael J. Havey

resolved from short-day (SD) tropical types. However, the most notable feature of this ordination is the clear resolution of a group of Indian cultivars and landraces from the main grouping of SD populations. This grouping may represent populations more

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Frederick S. Davies and Michael A. Maurer

The research at Vero Beach was funded by the St. Johns River Water Management District and Indian River County.

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S.M. Scheiber, E.F. Gilman, D.R. Sandrock, M. Paz, C. Wiese, and Meghan M. Brennan

privet, fringe flower, oleander, japanese pittosporum, indian hawthorn, sweet viburnum, and sandankwa viburnum) were obtained from a commercial nursery in no. 1 or no. 2 containers. To be classified as a native Florida plant, the species it must have

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Amnon Levi, John Coffey, Laura Massey, Nihat Guner, Elad Oren, Yaakov Tadmor, and Kai-shu Ling

) were collected in the same geographic region (collected at the northern Indian desert of Rajasthan and the neighboring region of Punjab, Pakistan; Table 1 ) may imply that these three resistant PIs share similar ancestors and the resistance is

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Susan L.F. Meyer, Inga A. Zasada, Shannon M. Rupprecht, Mark J. VanGessel, Cerruti R.R. Hooks, Matthew J. Morra, and Kathryne L. Everts

tomato seedlings transplanted into soil amended with seed meals of indian mustard (InM), yellow mustard (YeM), mixtures of these mustard seed meals, linseed meal, or untreated with meal. All amendments were applied at a final total rate of 0.25% dry

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John M. Dole, Zenaida Viloria, Frankie L. Fanelli, and William Fonteno

flowers introduced to commercial markets each year, several show potential. ‘Lace Violet’ linaria, ‘Sunrise’ lupine, ‘Temptress’ poppy, and ‘Indian Summer’ rudbeckia are new species for the cut flower industry. ‘Karma Thalia’ dahlia, ‘Jemmy Royal Purple

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Eugene K. Blythe, Jeff L. Sibley, and John M. Ruter

Stem cuttings of golden euonymus (Euonymus japonicus `Aureo-marginatus'), shore juniper (Juniperus conferta `Blue Pacific'), white indian hawthorn (Rhaphiolepis indica `Alba'), and `Red Cascade' miniature rose (Rosa `Red Cascade') were successfully rooted in plugs of a stabilized organic substrate that had been soaked in aqueous solutions of the potassium salt of indole-3-butyric acid (K-IBA) at 0 to 75 mg·L–1 before inserting the cuttings. Cuttings were rooted under intermittent mist in polyethylene-covered greenhouses with rooting periods appropriate for each species. Rooting percentages showed some increase with increasing auxin concentration with juniper cuttings, but were similar among treatments for the other three species. Number of roots per rooted cutting increased with increasing auxin concentration with cuttings of juniper, Indian hawthorn, and rose, and was greatest using around 60 mg·L-1 K-IBA for cuttings of juniper and Indian hawthorn and 30 to 45 mg·L-1 K-IBA for cuttings of rose.