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Except for Thermopsis barbata Benth. ex Royle, which produces reddish-purple flowers, all species in Thermopsis have yellow flowers ( Chen et al., 1994 ; Wu and Raven, 1994 ). Flower color in Baptisia ranges from white to yellow to blue

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Shoot explants from actively growing, greenhouse-maintained plants of Baptisia `Purple Smoke' were cultured in vitro for shoot initiation on Murashige and Skoog (MS) basal medium containing vitamins and supplemented with 30 g·L–1 sucrose, 8.87 μm BA, and 4.14 μm K-IBA. All subsequent media were supplemented with 2.47 mm NaH2PO4 to enhance shoot growth. Single-node explants were subcultured for shoot multiplication on MS medium with either no plant growth regulator or with 2.22, 4.44, 8.87, 17.74, or 35.48 mm BA in combination with 0.0 or 4.14 μm K-IBA. Explants produced a maximum of 4.1 shoots on the medium with 2.22 μm BA. Shoots rooted on all concentrations of K-IBA (2.07, 4.14, 10.36, or 20.72 μm) and K-NAA (2.23, 4.46, 11.15, or 22.29 μm) tested. Maximum rooting was 100% on MS medium with 11.15 μm K-NAA; however, this treatment induced copious stem callusing. Rooted shoots were greenhouse-acclimatized for 2.5 weeks. Overall survival was 86%. For optimal rooting and subsequent acclimatization, treatment with 2.23 μm K-NAA is recommended; this resulted in 83% rooting and 87% acclimatization. Chemical names used: N 6 benzyladenine (BA); potassium salt of indole-3-butyric acid (K-IBA); potassium salt of 1-naphthalene acetic acid (K-NAA).

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 al. 2015 ; Kirk Visscher and Seeley 1982 ; Seeley 1995 ). Herbaceous perennial native species and ornamental cultivars of the following genera were evaluated: Baptisia , Hylotelephium , Monarda , and Symphyotrichum ( Table 1 ). These genera are

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Native plants are often ignored in horticulture because they may lack major ornamental traits and many of them are difficult to propagate. Creamy indigo (Baptisia bracteata Mnhl.) is a North American legume with considerable potential as a container-grown or ornamental plant for managed landscapes. Nodal explants from aseptically germinated seedlings were evaluated for axilary shoot and leaf development. The explants were cultured on Murashige and Skoog medium (MS) containing adenine sulfate at 80 mg•L-1, 30% sucrose, and different levels of N-6-benzyladenine (BA) (0.5,1.0,2.0 mg•L-1) supplemented with indole-3-acetic acid (IAA) (0.05, 0.1 or 0.5 mg•L-1) or with IAA omitted. Shoot regeneration occurred within 2 to 3 weeks. The best medium for shoot regeneration was MS supplemented with BA at 1.0 mg and IAA at 0.1 mg•L-1. Shoots were transferred onto rooting medium consisting of Ω MS supplemented with 1.0 mg alpha-naphthaleneacetic acid (NAA) and 1.0 mg indole-3-butyric acid (IBA)/L and 20% sucrose. Rooting took place within 3 to 5 weeks. Plantlets were then planted in soil mix, placed under a polyethylene tent for 2 weeks, and transferred into the greenhouse for further growth.

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A series of experiments was performed to examine the germination responses of Baptisia australis (L.) R. Br. seeds. Germination tests were conducted at 23 °C and numbers of germinated seed were counted daily for 21 days. Seeds were separated into two size fractions using standard sieves. Seeds in the large-seeded fraction were heavier than those in the small-seeded fraction, but seed size/weight did not affect the germination percentage at 21 days (G21), the number of days to 50% of final germination (T50), or the number of days between 10% and 90% germination (T90 – T10). Seeds were classified into two groups based on testa color. Light-brown seeds (17% of total) were heavier and had lower G21 and higher T50 and T90 – T10 values than medium- to dark-brown seeds (83% of total). Seeds scarified mechanically germinated nearly 100% and had lower T50 and T90 – T10 values than untreated seeds. Untreated seeds had a higher T50 value than seeds soaked overnight in 20°C water, but the G21 and T90-T10 values were similar for the two treatments. Mechanical scarification followed by overnight soaking in 20 °C water yielded a G21 value of only 12%, and the low germination percentage was attributed to imbibition damage. When seeds were scarified in concentrated H2SO4 for 0, 1, 5, 20, 40, or 80 min, G21 values increased quadratically while T50 and T90 – T10 values decreased quadratically as the immersion time increased. To test the effects of moist heat on germination responses, seeds were immersed for 0, 0.5, 1, 2, 4, or 8 minutes in 85 °C water. G21 values increased linearly as the immersion period increased from 0 to 2 min but remained similar when the immersion time exceeded 2 min. The duration of immersion in hot water did not affect the T50 values whereas T90 – T10 values decreased linearly as the immersion period increased. We conclude that physical dormancy is responsible for temporal variation in germination of B. australis seeds. Scarifying seed in concentrated H2SO4 for 20 to 80 minutes may be the most practical means of treating bulk lots of B. australis seeds to obtain rapid and uniform (≥85%) germination.

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The effect of cold on germination rate, percentage and range of five cut flowers was investigated: Baptisia australis (Wild Blue Indigo), Echinacea purpurea (Purple Coneflower), Helianthus maximilianii (Maximillian Sunflower), Solidago petiolaris (Spike Goldenrod), and Vernonia missurica (lronweed). Viability was determined for the species using TTC staining and germination based on percent viable seed. Seeds were given 0, 2, 4, 6, 8, or 10 weeks of cold at 5°C. Increasing weeks of cold decreased days to germination in all five species, with Baptisia demonstrating the greatest effect. The germination percent increased as weeks of cold increased in all five species, but was most significant in Helianthus and Vernonia. Days from first to last germinating seed was significantly decreased in all five species as weeks of cold increased. Four weeks of cold was optimum for Echinacea and Vernonia, while optimum weeks of cold for Helianthus and Solidago was six weeks and Baptisia ten weeks.

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The germination responses of wild blue indigo [Baptisia australis (L.) R. Br.], purple coneflower [Echinacea purpurea (L.) Moench.], Maximilian sunflower (Helianthus maximiliani Schrad.), spike goldenrod (Solidago petiolaris Ait.), and Missouri ironweed (Vernonia missurica Raf.) seeds after 0, 2, 4, 6, 8, or 10 weeks of stratification at 5C were investigated. Seed viability was determined using triphenyl tetrazolium chloride staining and germination based on the percentage of viable seeds. Germination percentage (GP) increased in all five species as weeks of stratification increased. Days to first germination and germination range (days from first to last germinating seed) decreased with increasing weeks of stratification, but the effect beyond 4 to 6 weeks was minimal. The number of weeks of stratification for maximum GP was 4 for purple coneflower, 6 for Maximilian sunflower, 8 for Missouri ironweed, and 10 for wild blue indigo and spike goldenrod.

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During the 2004 season, preemergence herbicide was applied to 12 container-grown herbaceous perennials and woody plants and evaluated for weed control, phytotoxicity, and effect on plant growth. The herbicide and rates were: pendimethalin (Pendulum 2G) 908 g (label rate), 1816 g, and 3632 g/acre a.i. Herbicides were applied to lady's mantle (Alchemilla mollis), purple rock cress (Aubretia species), blue wild indigo (Baptisia australis), pink pussytoes (Antennaria dioica var. rosea), common sneezeweed (Helenium autumnale), redhot poker (Kniphofia uvaria), showy goldenrod (Solidago speciosa), heartleaf foamflower (Tiarella cordifolia), lavender (Lavendula angustifolia), blue flax (Linum perenne), catmint (Nepeta ×faassenii), and hen and chicks (Sempervivum tectorum). At 32 and 117 days after application, plants were evaluated for phytotoxicity. No phytotoxicity symptoms were apparent on any of the plants tested. Weed control was good in most cases with this herbicide but it did not control all weeds. Increasing the rates from 1× (label rate) did not significantly improve weed control.

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Abstract

Seedlings of Baptisia australis (L.) R. Br. and Liatris aspera Michx., grown in prairie soil with no additional P, benefited significantly from inoculation with Glomus etunicatum Becker and Gerd., regardless of whether they were adequately watered or moderately or severely drought-stressed. In the presence of additional P, growth of severely droughted inoculated seedlings for both plant species was not significantly greater than noninoculated plants. When the influence of four Glomus species on growth of the two forbs was compared under drought-stress conditions with no supplemental P, growth of both plant species was signficantly improved by all fungal species compared to noninoculated controls. Preinoculated seedlings of both plant species were transplanted into disturbed-site soils with indigenous vesicular-arbuscular mycorrhizal (VAM) fungi present and subjected to severe moisture stress. After 12 weeks, inoculated seedlings were significantly larger than noninoculated seedlings for all soil types, with or without additional fertilizer (0.15 kg P/m3 + 0.075 kg N/m3). Under conditions of drought stress and low fertility, preinoculated seedlings of both B. australis and L. aspera grew significantly larger than noninoculated seedlings.

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In 1991, the USDA–ARS North Central Regional Plant Introduction Station made available for distribution 129 accessions of germplasm representing 31 genera of herbaceous ornamentals. This number increased to 329 accessions of 42 genera by 1995. During 1991–95, more than 500 seed packets were distributed to fulfill requests for these plants received from a diverse array of public and private researchers. An analysis of this demand together with expert advice from Crop Germplasm Committees and technical considerations, such as ease of culture and seed production, can help set priorities to plan germplasm regeneration to meet future demand. A recent analysis of demand at U.S. National Plant Germplasm System active sites indicated that demand ranging between 0.23 and 0.97 distributions per available accession per year was typical. Of the 42 ornamental genera analyzed in this study, 9 were demanded more frequently than was typical, 10 were demanded less frequently, with the remainder in the typical range. In order of increasing frequency, the nine genera with the highest distribution rates were Verbena, Gypsophila, Echinacea, Lapeirousia, Delphinium, Cerastium, Baptisia, Lilium, and Tanacetum. Six of these genera are represented only by a single available accession. Notably, Echinacea and Tanacetum are of research interest both as ornamentals and as medicinal/industrial crops. This poster gives a brief overview of the economic value of these genera, display the results of the demand analysis, discuss the results relative to recommendations from Crop Germplasm Committees and requestors, and consider how demand can shape management plans for the acquisition and regeneration of ornamental germplasm.

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