Phlox Paniculata Research Articles

Shoot Regeneration from Leaf Tißues of Phlox paniculata L.

Summary A highly efficient shoot regeneration system from greenhouse-grown leaf tisues of Phlox paniculata cvs. Franz Schubert and Prospero was developed. In a preliminary experiment, both TDZ and BA (at 5 μmol/L each) along with 2.5 μmol/L IAA, induced almost a 100 % regeneration frequency for both genotypes, especially when explants were grown without any dark treatment. Moreover, significant differences were observed in regenerability of explants collected from first, second, and third nodes. In a factorial experiment with four BA or four TDZ levels (0.25, 1, 3, and 5 μmol/L) along with three IAA levels (0, 0.5 and 1.0 μmol/L), Franz Schubert, leaf explants exhibited significant differences in shoot organogenesis (mean number of sites of organogenesis/explant, callus development, % explants with>6 shoots/explant) and overall quality of shoot regenerants (mean length of longest shoot, hyperhydration). Results of a principal component analysis indicated that, overall, BA was more effective than TDZ in inducing more shoots and more regeneration sites per explant, and with les callus development. However, hyperhydration (vitrification) of shoot regenerants on media containing 1 μmol/L BA and 0 or 0.5 μmol/L IAA prevented further elongation of these shoots. In another factorial experiment, low levels of both BA (0.5 to 1.5 μmol/L) and IAA (0 to 1 μmol/L) were also investigated. It was observed that all shoot organogenesis occurred along the cut margins of leaf segments and without an intervening callus stage when explants were grown on an MS medium supplemented with 0.5 μmol/L BA and 0.5 μmol/L IAA. Elongation of shoot regenerants was achieved when these were transferred to an MS medium without growth regulators.

Evaluation of Weed Control and Phytotoxicity of Preemergence Herbicides Applied to Container-grown Herbaceous and Woody Plants

Abstract Six different preemergence herbicides were used with eight different plant species to evaluate weed control efficacy and possible phytotoxicity. The species used were Stachys byzantina C. Koch (lamb's ears), Campanula persicifolia L. (peachleaf bellflower), Achillea millefolium L. ‘Summer Pastel’ (common yarrow), Coreopsis lanceolata L. (Lance coreopsis), Gypsophila pacifica Kom. (baby's breath), Wisteria sinensis Sims (Chinese wisteria), Syringa vulgaris L. (common lilac), Phlox paniculata L. (perennial phlox), Dahlia Cav. x hybrida (garden dahlia). Herbicides were applied to the soil surface at rates of lx and 2x as recommended by the label. The herbicides and rates were as follows: Pennant (Dual) 7.8 Liquid, 4.6, 9.1 kg ai/ha (4, 8 lb ai/A); Gallery 75DF, 1.1, 2.3 kg ai/ha (1, 2 lb ai/A); Ronstar 2G, 4.5, 9.0 kg ai/ha (4, 8 lb ai/A); Rout 3G, 3.4, 6.8, 13.6 kg ai/ha (3, 6, 12 lb ai/A); Surflan AS, 2.3, 4.6 kg ai/ha (2, 4 lb ai/A); and Treflan 5G, 4.5, 9.0 kg ai/ha (4, 8 lbs ai/A). Weed seeds of Setaria glauca (L.) Beauv. (yellow foxtail), Echinochloa crus-galli (L.) Beauv. (barnyardgrass), Poa annua L. (annual bluegrass), Capsella bursa-pastoris (L.) Medik. (shepherdspurse), Senecio vulgaris L. (common groundsel), and Amaranthus retroflexus L. (redroot pigweed) were sown on the soil surface. Two control treatments (no herbicide and no weed seeds applied, or no herbicide but with weed seeds) also were evaluated. Plants were grown in #1 black plastic containers in a medium of clay loam soil, plaster sand and sphagnum peat (1:1:2 by vol). Weed counts at the end of the season indicated that weed control was variable according to the herbicide used. Rout and Ronstar at both the lx and 2x rates controlled over 99% of the weeds (compared to the control treatment with weeds). Weed control for the other herbicides were as follows: Surflan lx = 92%, Surflan 2x = 95%, Pennant lx = 93%, Pennant 2x = 98%, Gallery lx = 35%, Gallery 2x = 43%, Treflan 1x = 88%, and Treflan 2x = 96%. Evaluations also indicated that herbicides utilizing oryzalin resulted in phytoxicity or stunting to Phlox (appearance declined 88% at the 1x rate and 93% at the 2x rate compared to the control treatment), Gypsophila (dry weights for Surflan 1x was 27% less and Surflan 2x was 39% less compared to the control treatment), and Stachys (appearance declined 55% for 1x rate and 60% at the 2x rate). Gallery (isoxaben) resulted in stunting in Stachys (dry weights for Gallery 1x were 75% less compared to control plants and Gallery 2x was 80% less).

PREEMERGENT WEED CONTROL IN CONTAINER-GROWN LANDSCAPE PLANTS

Herbicides were applied to container grown landscape plants and evaluated on the basis of weed control, phytotoxicity, and effect on plant growth. Three preemergent herbicides were applied including: Oxadiazon (Ronstar) at 4.54 and 9.08 kg/ha, Oxyfluorfen + Oryzalin (Rout) at 3.41 and 6.81 kg/ha and Oryzalin (Surflan) at 2.27 and 4.54 kg/ha. There was also a weedy and non-weedy control. The plant species included: Syringa vulgaris (Common Lilac), Wisteria sinensis (Chinese Wisteria), Phlox paniculata (Garden Phlox) and Dahlia hybrid (Garden Dahlia). They were all grown in number one containers in a media of soil, spaghnum peat moss, and plaster sand (1:2:1 by volume). All herbicides tested controlled weeds effectively with no phytotoxicity except with Phlox paniculata. Oryzalin resulted in a phytotoxic effect on Phlox paniculata at both the 1x and 2x rates.

The appearance of soil-borne viruses in Finnish plant nurseries II

In the beginning of the 1970’s, the occurrence of soil-borne viruses in 30 Finnish nurseries and experimental fields of garden plants at 3 research stations was mapped. Viruses were isolated on 26.9 % of the 672 plant and soil samples collected. The two most commonly found viruses were tobacco necrosis virus (TNV), 42.5 %, and tobacco rattle virus (TRV), 23.7 %. Tomato black ring virus (TBRV) and raspberry ringspot virus (RRSV) were isolated for the first time in Finland. The abundant occurence of TBRV in 32 samples was due to the abundance of Phlox paniculata samples. RRSV was isolated from only a few samples. The vectors of all of the above-mentioned viruses were found in many samples. The fungus vector of TNV, Olpidium brassicae, was investigated by examining the roots microscopically. The vector of TRV, the Trichodorus sp. nematodes, and the vector of TBRV and RRSV, the Longidorus sp. nematodes, were isolated from soil samples. In addition to the foregoing, tobacco mosaic virus was isolated from 31 samples of 6 nurseries and 2 experimental fields. Viruses were isolated from many weed samples, especially from roots of Senecio vulgaris and Stellaria media. Perennials proved to be virotic. All of the above mentioned viruses, especially TBRV and TRV, were isolated from Phlox paniculata; TBRV was also found in an Astilbe x arendsii sample. Dicentra spectabilis, like Phlox, was commonly infected with TRV. No clear results could be obtained from control experiments.

POPULATION AND GENOTYPE NICHE WIDTH IN CLONAL PHLOX PANICULATA

We use a model population comprised of five genotypes of Phlox paniculata L. to investigate the contribution of individuals to the response breadth (niche) of the population on a light gradient and a moisture gradient. Analysis of within‐ and between‐genotype components of population response width showed up to 20% of the response is due to between‐genotype effects, depending upon the character considered. Since the only way a sedentary organism can deal with a variable environment is through plasticity of response, differences in levels of phenotypic plasticity between genotypes on the two resource gradients were also investigated. There was no correlation between level of phenotypic plasticity and success over a range of environments. Niche breadth calculated as Levins' (B) and Roughgarden's (w2) indicated that flowering, and hence sexual reproduction, was limited to a much narrower range of environments than was vegetative growth. We also found significant genotype × environment interactions on both gradients, indicating differences in genetic response to the environment.

Population and Genotype Niche Width in Clonal Phlox paniculata

We use a model population comprised of five genotypes of Phlox paniculata L. to investigate the contribution of individuals to the response breadth (niche) of the population on a light gradient and a moisture gradient. Analysis of within- and between-genotype components of population response width showed up to 20% of the response is due to between-genotype effects, depending upon the character considered. Since the only way a sedentary organism can deal with a variable environment is through plasticity of response, differences in levels of phenotypic plasticity between genotypes on the two resource gradients were also investigated. There was no correlation between level of phenotypic plasticity and success over a range of environments. Niche breadth calculated as Levins' (B) and Roughgarden's (w2) indicated that flowering, and hence sexual reproduction, was limited to a much narrower range of environments than was vegetative growth. We also found significant genotype × environment interactions on both gradients, indicating differences in genetic response to the environment.

Leaf Demography and Plant-Insect Interactions: Goldenrods and Phloem-Feeding Aphids

Previous articleNext article No AccessNotes and CommentsLeaf Demography and Plant-Insect Interactions: Goldenrods and Phloem-Feeding AphidsD. C. Hartnett and F. A. BazzazD. C. Hartnett Search for more articles by this author and F. A. Bazzaz Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The American Naturalist Volume 124, Number 1Jul., 1984 Published for The American Society of Naturalists Article DOIhttps://doi.org/10.1086/284258 Views: 8Total views on this site Citations: 22Citations are reported from Crossref Copyright 1984 The University of ChicagoPDF download Crossref reports the following articles citing this article: 10.1007/BF00333819, CrossRef Listing of Deleted DOIs 58 (Jan 2011).https://doi.org/10.1007/BF00333819Jun-Ya Ide Inter- and intra-shoot distributions of the ramie moth caterpillar, Arcte coerulea (Lepidoptera: Noctuidae), in ramie shrubs, Applied Entomology and Zoology 41, no.11 (Jan 2006): 49–55.https://doi.org/10.1303/aez.2006.49P. W. LAMBDON, M. HASSALL How should toxic secondary metabolites be distributed between the leaves of a fast-growing plant to minimize the impact of herbivory?, Functional Ecology 19, no.22 (Apr 2005): 299–305.https://doi.org/10.1111/j.0269-8463.2005.00966.xD. Alexander Wait, James S. Coleman, Clive G. Jones Chrysomela scripta , Plagiodera versicolora (Coleoptera: Chrysomelidae), and Trichoplusia ni (Lepidoptera: Noctuidae) Track Specific Leaf Developmental Stages, Environmental Entomology 31, no.55 (Oct 2002): 836–843.https://doi.org/10.1603/0046-225X-31.5.836Eliot J. B. McIntire, David S. Hik Grazing history versus current grazing: leaf demography and compensatory growth of three alpine plants in response to a native herbivore (Ochotona collaris), Journal of Ecology 90, no.22 (Apr 2002): 348–359.https://doi.org/10.1046/j.1365-2745.2001.00672.xPAULA J. PEETERS, JENNIFER READ, GORDON D. SANSON Variation in the guild composition of herbivorous insect assemblages among co-occurring plant species, Austral Ecology 26, no.44 (Jun 2008): 385–399.https://doi.org/10.1111/j.1442-9993.2001.tb00118.xGina M. Wimp, Thomas G. Whitham BIODIVERSITY CONSEQUENCES OF PREDATION AND HOST PLANT HYBRIDIZATION ON AN APHID–ANT MUTUALISM, Ecology 82, no.22 (Feb 2001): 440–452.https://doi.org/10.1890/0012-9658(2001)082[0440:BCOPAH]2.0.CO;2Paula J. Peeters, Jennifer Read, Gordon D. Sanson , Austral Ecology 26, no.44 ( 2001): 385.https://doi.org/10.1046/j.1442-9993.2001.01123.xEwald Weber Biological flora of Central Europe: Solidago altissima L., Flora 195, no.22 (Apr 2000): 123–134.https://doi.org/10.1016/S0367-2530(17)30960-XC. M. Mabry, M. Jasieński, J. S. Coleman, F. A. Bazzaz Genotypic variation in Polygonum pensylvanicum : nutrient effects on plant growth and aphid infestation, Canadian Journal of Botany 75, no.44 (Apr 1997): 546–551.https://doi.org/10.1139/b97-060A. Jobin, U. Schaffner, W. Nentwig The structure of the phytophagous insect fauna on the introduced weed Solidago altissima in Switzerland, Entomologia Experimentalis et Applicata 79, no.11 (Mar 2011): 33–42.https://doi.org/10.1111/j.1570-7458.1996.tb00806.xMARC-ANDRÉ MARTIN, NAOMI CAPPUCCINO, DOMINIC DUCHARME Performance of Symydobius americanus (Homoptera: Aphididae) on paper birch grazed by caterpillars, Ecological Entomology 19, no.11 (Feb 1994): 6–10.https://doi.org/10.1111/j.1365-2311.1994.tb00383.xMOSHE BURSTEIN, DAVID WOOL Gall aphids do not select optimal galling sites (Smynthurodes betae; Pemphigidae), Ecological Entomology 18, no.22 (May 1993): 155–164.https://doi.org/10.1111/j.1365-2311.1993.tb01197.xGretchen A. Meyer, Thomas H. Whitlow Effects of leaf and sap feeding insects on photosynthetic rates of goldenrod, Oecologia 92, no.44 (Jan 1992): 480–489.https://doi.org/10.1007/BF00317839Juan Núñez-Farfán, Rodolfo Dirzo Effects of defoliation on the saplings of a gap-colonizing neotropical tree, Journal of Vegetation Science 2, no.44 (Feb 2009): 459–464.https://doi.org/10.2307/3236027Katherine C. Larson, Thomas G. Whitham Manipulation of food resources by a gall-forming aphid: the physiology of sink-source interactions, Oecologia 88, no.11 (Jan 1991): 15–21.https://doi.org/10.1007/BF00328398John L. Harper The value of a leaf, Oecologia 80, no.11 (Mar 2013): 53–58.https://doi.org/10.1007/BF00789931B. Schmid, G. M. Puttick, K. H. Burgess, F. A. Bazzaz Correlations between genet architecture and some life history features in three species of Solidago, Oecologia 75, no.33 (Apr 1988): 459–464.https://doi.org/10.1007/BF00376952 The effects of severe mineral nutrient deficiencies on the demography of leaves, Proceedings of the Royal Society of London. Series B. Biological Sciences 232, no.12671267 (Jan 1997): 137–157.https://doi.org/10.1098/rspb.1987.0065K. Garbutt GENETIC DIFFERENTIATION IN LEAF AND WHOLE PLANT PHOTOSYNTHETIC CAPACITY AND UNIT LEAF RATE AMONG CLONES OF PHLOX PANICULATA, American Journal of Botany 73, no.99 (Sep 1986): 1364–1371.https://doi.org/10.1002/j.1537-2197.1986.tb10877.x David C. Hartnett , and Fakhri A. Bazzaz Leaf Demography and Plant-Insect Interactions: A Further Comment, The American Naturalist 127, no.44 (Oct 2015): 561–564.https://doi.org/10.1086/284503 A. F. G. Dixon The Distribution of Aphid Infestation in Relation to the Demography of Plant Parts: A Reply, The American Naturalist 127, no.33 (Oct 2015): 410–413.https://doi.org/10.1086/284492

RESISTANCE TO POWDERY MILDEW IN PERENNIAL PHLOX

Forty-nine cultivars of perennial phlox, Phlox paniculata L., grown in a field plot at Ottawa were compared for resistance to powdery mildew in 1961, 1962, and 1963. None of the cultivars was immune. A seedling, designated by the number 60–75, showed field resistance to mildew that was significantly better than the other cultivars for 3 years but subsequently became susceptible. A second cultivar, Pyramid White, initially showed field resistance to powdery mildew but it became susceptible to the disease more quickly than 60–75. Results obtained under the conditions of our experiments suggested that first-year plants were more resistant to powdery mildew than plants of the same cultivars that were at least 3 years old. In breeding for resistance, only a few seeds from crosses germinated but one apparently resistant seedling was obtained. However, this seedling subsequently became susceptible.