Phlox Paniculata Research Articles

Physiological response of Phlox paniculata L. varieties to different growing conditions of Western Siberia

Physiological indicators of plants are essential characteristics of plant adaptation to adverse environmental factors. Phlox paniculata varieties (originated from North America) introduced into the southern taiga subzone of Western Siberia experience stress caused by numerous factors. The physiological response to different growing conditions of the southern taiga subzone of Western Siberia was analyzed for 3 varieties of Ph. paniculata. The study employed handheld optical instruments for vital analysis of plant physiological parameters: a compact LI-600P porometer (LI-COR) and a CI-710 leaf spectrometer (CID Bio-Science). Stomatal conductance of phlox leaves in partial shade studied with respect to different varieties was found to virtually remain unchanged. The studied varieties exhibit different degree of resistance to water deficiency. The variety ‘Stanislas’ was found to be resistant to insufficient soil humidity and light, it can be grown in both moderately shaded areas and arid conditions. The studied varieties showed high indices of anthocyanins and carotenoids under good light conditions and natural humidity, which indicates these conditions as the most stressful for Ph. paniculata due to a high degree of water and temperature stress. The greatest difference in the measured indices was found for the variety ‘Antarktida’, which indicates its susceptibility to water deficiency.

Influence of the preparation «Lignohumate» on the decorative effect of perennial plants

Purpose of the article is to study the effectiveness of the «Lignohumate» preparation on the growth, development and decorative qualities of some flower and ornamental crops (Campanula persicifolia L., C. carpatica Jacg., Phlox paniculata L.) in the forest-steppe zone of the Bashkir Cis-Ural. Observations of the seasonal rhythm of plant development were carried out according to the method of phenological observations in botanical gardens, the assessment of ornamental features was carried out according to the generally accepted method of state variety testing of ornamental crops. For the first time in the conditions of the Bashkir Cis-Ural, the influence of the growth stimulator «Lignohumate» on the decorative qualities of some types of flower crops of the collection of the SUBGI UFRC RAS was studied. The features of phenology, growth, as well as the decorative qualities of plants during fertigation with a growth regulator are analyzed. When evaluating decorativeness on a 100-point scale in C. persicifolia, it was found out that «Lignohumate» is effective for such decorative features as the number of leaves, the abundance of flowering and the density of the inflorescence; there is also a reduction in the duration of the period from regrowth to flowering by 5 days. In C. carpatica, such morphometric parameters as flower and inflorescence size, abundance and duration of flowering have improved; also, the preparation helps to increase the area of the horizontal projection of the color spot on the bush by 2.6 times compared to the control. In Ph. paniculata «Lignohumate» is effective for such decorative features as the size of the inflorescence, the abundance and duration of flowering, also during fertigation, the area of the horizontal projection of the color spot on the bush increased by 1.5 times, thereby increasing the decorative qualities of the phlox.

Влияние стимулятора роста на биолого- морфологические параметры многолетних травянистых растений

Abstract. Purpose is to study the effectiveness of the “Lignogumat” drug on the growth, development and decorative qualities of some flower and ornamental crops (Campanula persicifolia L., C. carpatica Jacg., Phlox paniculata L.) in the forest-steppe zone of the Bashkir Cis-Ural. Methods. Observations of the seasonal rhythm of plant development were carried out according to the method of phenological observations in botanical gardens, the assessment of ornamental features was carried out according to the generally accepted method of state variety testing of ornamental crops. Scientific novelty. For the first time in the conditions of the Bashkir Cis-Ural, the influence of the growth stimulator “Lignogumat” on the decorative qualities of some types of flower crops of the collection of the SUBGI UFRC RAS was studied. Results. The features of phenology, growth, as well as the decorative qualities of plants during fertigation with a growth regulator are analyzed. When evaluating decorativeness on a 100-point scale in C. persicifolia, it was found that “Lignogumat” is effective for such decorative features as the number of leaves, the abundance of flowering and the density of the inflorescence; there is also a reduction in the duration of the period from regrowth to flowering by 5 days. In C. carpatica, such morphometric parameters as flower and inflorescence size, abundance and duration of flowering have improved; also, the drug helps to increase the area of the horizontal projection of the color spot on the bush by 2.6 times compared to the control. Ph. paniculata “Lignogumat” is effective for such decorative features as the size of the inflorescence, the abundance and duration of flowering, also during fertigation, the area of the horizontal projection of the color spot on the bush increased by 1.5 times, thereby increasing the decorative qualities of the phlox.

Selection of phlox (Phlox paniculata) in the Siberian Botanical Garden, Tomsk State University

Selection of phlox (Phlox paniculata) in the Siberian Botanical Garden, Tomsk State University

Phlox paniculata (summer perennial phlox)

This datasheet on Phlox paniculata covers Identity, Distribution, Uses.

ОЦЕНКА КОЛЛЕКЦИИ ОТЕЧЕСТВЕННЫХ СОРТОВ ФЛОКСА МЕТЕЛЬЧАТОГО (PHLOX PANICULATA L.) ГБС ИМ. Н.В. ЦИЦИНА ПО МОРФОЛОГИЧЕСКИМ ПРИЗНАКАМ

The study evaluated the morphological characteristics of the collection of Paniculate phlox domestic cultivars (Phlox paniculata L.) of N.V. Tsitsin’s Botanical Garden of the Russian Academy of Sciences. Cultivars were rated by valuable decorative features in order to select a new breeding material suitable for use in cut flower production and gardening. Accounting of economic and decorative features were carried out within two years, in accordance with the methodology of state cultivar testing. The data obtained are statistically reliable. The complex of morphological features revealed promising domestic cultivars – ‘Gegery’, ‘Timur’, ‘Rozovy kovyor’, ‘Michurinets’, ‘Sigismund Levanevsky’, ‘Atlas’ and ‘Nebesa’, which are valuable breeding source material for domestic cut flower production.

Propagation of herbaceous unrooted cuttings of cold-tolerant species under reduced air temperature and root-zone heating

Vegetative propagation of herbaceous cuttings mostly occurs in greenhouses during late winter and early spring when outdoor radiation intensities and average daily temperatures (ADT) are seasonally low. To promote rapid callus induction and rooting, supplemental lighting and air and root-zone heating (RZH) can be utilized. Given that cold-tolerant crops have base temperatures <4 °C, reducing the air temperature is a potential energy saving strategy. Therefore, the objective of this study was to quantify how reduced air ADT and increased RZH temperatures influence root initiation and development of cold-tolerant herbaceous annual and perennial crops propagated by cuttings. Shoot-tip cuttings of calibrachoa ‘Callie Coral’ (Calibrachoa ×hybrida), campanula ‘Birch Hybrid’ (Campanula portenschlagiana), nemesia ‘Aromatica Royal Blue’ (Nemesia fruticans), nepeta ‘Junior Walker’ (Nepeta × faassenii), osteospermum ‘Voltage Yellow’ (Osteospermum ecklonis), petunia ‘Sanguna Patio Blue’ (Petunia ×hybrida), phlox ‘Glamour Girl’ (Phlox paniculata), and rosemary ‘Arp’ (Rosmarinus officinalis) were inserted into a soilless medium and grown in a greenhouse with an air ADT and RZH temperature of 21 and 24 °C, respectively, for callusing. After 6 d, trays of cuttings were placed in two greenhouse compartments with air ADTs of 16 or 21 °C. Three benches within each compartment had RZH set points of 21, 24, or 27 °C. After 14 d, the interaction of air and RZH temperatures influenced stem length of nepeta, petunia, phlox, and rosemary. For example, increasing the air ADT from 16 to 21 °C and RZH set points from 21 to 27 °C increased stem length of nepeta by 2.5 to 3.7 cm. As air ADT increased from 16 to 21 °C at an RZH set point of 27 °C, shoot dry mass increased by 32% and 24% for calibrachoa and phlox, respectively. Root dry mass and liner pullability for osteospermum increased as air ADT increased from 16 to 21 °C at an RZH set point of 21 °C by 14 mg and 70%, respectively. Overall, the results from this study identify cold-tolerant crops that can be propagated with genera-specific RZH set points under a reduced air ADT without sacrificing liner quality or propagation time and highlights the importance of RZH for growers.

НОВІ ЗНАХІДКИ ЧУЖОРІДНИХ РОСЛИН-ЕРГАЗІОФІТІВ У ЛІВОБЕРЕЖНОМУ ЛІСОСТЕПУ УКРАЇНИ

The article summarizes the data on the distribution of 25 alien vascular plants in the territory of the Left Bank Forest-Steppe of Ukraine. All of them are ergaziophytes (mostly ornamental plants) escaped from their areas of cultivation. Ten species (Callistephus chinensis (L.) Nees, Iberis umbellata L., Lobularia maritima (L.) Desv., Ricinus communis L., Hemerocallis fulva (L.) L., Iris germanica L., Salvia sclarea L., Mirabilis jalapa L., Sorghum drummondii (Nees ex Steud.) Millsp. &amp; Chase and Viola sororia Willd.) have been firstly found as wild plants in this region. Four species (Rudbeckia triloba L., Euphorbia marginata Pursh, Portulaca grandiflora Hook. and Solanum lycopersicum L.) are new for Poltava region, one(Solidago gigantea W.T. Aiton) – for Sumy region, two (Allium tuberosum Rottler ex Spreng. and Salvia sclarea L.) – for Kharkiv city and Kharkiv region. The data of distribution of Amaranthus caudatus L. in the Left Bank Forest-Steppe of Ukraine were confirmed by herbarium specimen. Other eight species (Allium schoenoprasum L., Calendula officinalis L., Heliopsis helianthoides (L.) Sweet, Symphyotrichum novae-angliae (L.) G.L. Nesom, Dianthus barbatus L., Phedimus spurius (M. Bieb.) 't Hart, Phlox paniculata L., Solanum tuberosum L.) belong to locally distributed alien plants. Based on analysis of the chorology of these species, it is found that eight alien plants have North-American origin, other main regional chorological groups are represented by species from Eastern Asia (4), South America (3) and Europe (3). Major part of the found alien plants includes ephemerophytes in the Left Bank Forest-Steppe of Ukraine (22 species), only three representatives (Heliopsis helianthoides, Phedimus spurius and Solidago gigantea) are naturalized on this territory and belong to the stable floristic component. Two species (Hemerocallis fulva and Iris germanica) are sporadically distributed in different locations, but represented by vegetative clones only and have not been considered as elements of the spontaneous flora. Key words: adventive plants, new localities, Forest-Steppe zone.

Annuals and Herbaceous Perennials Tolerant or Resistant to Phytophthora Species in the Landscape1

Abstract Plants of one or two cultivars of 16 annuals and 14 herbaceous perennials were evaluated based on desirability and anecdotal evidence of resistance to Phytophthora root or crown rot. Six plant cultivars served as susceptible controls. Three landscape beds were established in North Carolina and each was infested with three species of Phytophthora: P. nicotianae, P. drechsleri, and P. tropicalis. Plants were regularly rated for disease incidence and symptomatic plants were assayed to determine the presence of Phytophthora species. Ten cultivars of annuals and seven cultivars of herbaceous perennials did not exhibit symptoms of Phytophthora root or crown rot or other disease throughout the season (June 4 to October 15, 2018). Phytophthora spp. were recovered from seven and six cultivars of the evaluated annuals and herbaceous perennials, respectively. Phytophthora nicotianae, P. drechsleri, or P. cryptogea were recovered from a susceptible host in each landscape bed. P. tropicalis was recovered from one plant cultivar evaluated. Phytophthora cryptogea was recovered from three plant cultivars, although this species was not intentionally introduced in the landscape beds. We identified 22 plant cultivars within 13 herbaceous plant species that grew vigorously in landscape beds infested with species of Phytophthora. Index words: bedding plants, disease resistance, herbaceous perennials, landscape plants, Phytophthora nicotianae, Phytophthora drechsleri, Phytophthora tropicalis. Species used in this study: yarrow (Achillea millefolium L. ‘Desert Eve Red'), fernleaf yarrow (Achillea filipendulina Lam. ‘Moonshine Yellow'), angelonia (Angelonia angustifolia Benth. ‘ArchAngel Pink', ‘Serenita White'), annual vinca (Catharanthus roseus (L.) G. Don ‘Cora Apricot', ‘Cora Strawberry', ‘Pacifica Raspberry'), celosia (Celosia argentea L. ‘New Look'), tickseed (Coreopsis auriculata L. ‘Nana', ‘Yellow Jethro Tull'), purple coneflower (Echinacea purpurea (L.) Moench ‘Cheyenne Spirit', ‘PowWow Wild Berry'), blanket flower (Gaillardia x grandiflora Hort. ‘Goblin', ‘Mesa Bi-color'), Barberton daisy (Gerbera jamesonii Bolus ex Hooker f. ‘Crazy Daisy'), verbena (Glandularia canadensis ‘Homestead Purple'), &amp;gt;dusty miller (Jacobaea maritima (L.) Pelser &amp; Meijden ‘Silver Dust'), New Guinea impatiens (Impatienshawkeri W.Bull ‘Hamony', ‘Sunpatiens Compact Orchid', ‘Sunpatiens Lilac'), sweet potato vine (Ipomoea batatas (L.) Lam. ‘Ace of Spades', ‘Bright Idea Tri-color'), West Indian lantana (Lantana camara L. ‘Miss Huff'), lantana (Lantana x hybrida ‘New Gold'), shasta daisy (Leucanthemum x superbum (Bergmans ex J.W. Ingram) Bergmans ex Kent. ‘Becky', ‘Snow Lady'), bee balm (Monarda didyma L. ‘Petite Delight', ‘Jacob Cline'), ornamental grass (Panicum virgatum L. ‘Rotstrahlbusch', ‘Shenandoah'), geranium (Pelargonium x hortorum L.H. Bailey (pro. sp.) ‘Bullseye Cherry', Calliope Dark Red'), calibrachoa (Petunia x calibrachoa ‘Super Cal'), petunia (Petunia x hybrida (Hooker) Vilmorin ‘Easy Wave Red', ‘Easy Wave White', ‘Wave Purple', ‘Yellow Madness', Violet Picotee'), annual phlox (Phlox drummondii Hook. ‘Intensia Red Hot', ‘Phlox Star'), garden phlox (Phlox paniculata L. ‘Amethyst True Gal'), black-eyed susan (Rudbeckia hirta L. ‘Indian Summer', ‘Prairie Sun'), mealy blue sage (Salvia farinacea Benth. ‘Victoria Blue'), African marigold (Tagetes erecta L. ‘Inca Yellow', ‘Proud Yellow'), French marigold (Tagetes patula L. ‘Disco Mix', ‘Disco Yellow'), narrowleaf zinnia (Zinnia angustifolia Kunth. ‘Star Orange', ‘Star White'), Phytophthora nicotianae Breda de Haan, Phytophthora cryptogea Pethybr. and Laff, Phytophthora drechsleri Tucker, Phytophthora tropicalis Aragaki and J.Y. Uchida, zinnia (Zinnia elegans Jacq. ‘Magellan Orange').

Вміст біохімічних речовин у рослин Phlox paniculata L. в умовах Лісостепу України

Досліджено питання стійкості декоративних рослин Phlox paniculata L. до біотичного стресу. За результатами дослідження листків рослин 11 сортів Phlox paniculata з різним ступенем ураження збудником борошнистої роси (Erysiphe cichoracearum DC. f. phlogis Jacz.) визначено кількісний вміст біохімічних речовин (проліну, катехінів, флавонолів та антоціанів) в умовах Лісостепу України. Виявлено, що рослини, уражені збудником борошнистої роси, характеризувалися нижчим рівнем флавонолів (сорти 'Poliarnyi' – 0,268 мг/г, 'Mohuchii' – 0,354 мг/г), неуражені – вищим вмістом (сорти 'Mohuchii' – 0,729 мг/г та 'Fiosin' – 0,719 мг/г). Окрім цього, встановлено тенденцію до істотного збільшення вмісту катехінів у цілому на 8˗21 % в уражених борошнистою росою рослин, порівняно із неураженими. Відзначено певну закономірність щодо вмісту антоціанів: в уражених рослин він був на 18˗48 % вищим, ніж у неуражених. Зроблено висновок, що вторинні метаболіти є маркерами відповідної реакції та стійкості рослинного організму до стресу різного походження, оскільки під дією стресу, спричиненого збудником борошнистої роси, збільшується вміст флавонолів, катехінів та антоціанів. На відміну від інших показників, рівень проліну істотно не залежить від ступеня ураженості рослин Phlox paniculata збудником борошнистої роси, оскільки в цьому механізмі захисту рослин від стресу, спричиненого збудником борошнистої роси, діє інший механізм із залученням вторинних метаболітів.

Hydrogen sulfide mediated alleviation of cadmium toxicity in Phlox paniculata L. and establishment of a comprehensive evaluation model for corresponding strategy

A laboratory experiment was performed to evaluate the potential role of H2S on cadmium (Cd) toxicity in Phlox paniculata L. Seeds pretreated with 0.3, 0.6, 0.9, and 1.2 mM NaHS as a donor of H2S for 24 h and subsequently exposed to 100, 200, and 300 μM CdCl2 for 26 days had significantly higher germination rate compared with Cd alone. Meanwhile, 2-year-old seedlings sprayed with 0.3, 0.6, and 0.9 μM NaHS were grown in soil with 0.3, 0.6, and 1.2 mg/kg CdCl2, respectively. We observed that H2S decreased Cd accumulation in leaves and elevated Cd concentration in roots. Cd toxicity in seedlings resulted in a substantial increase in Cd-induced overproduction of malondialdehyde (MDA), Cd accumulation, and electrolyte leakage. Meanwhile, addition of NaHS increased photosynthetic performance compared with Cd alone. Exogenous H2S significantly elevated biomass, improved antioxidant enzyme activities, and reduced ABA content compared with Cd alone. H2S also plays an important role in the ABA signaling pathway during stress. Notably, NaHS promoted Cd uptake by Phlox paniculate L. from soil. The prediction model of H2S for increasing plant resistance and reducing soil Cd pollution was established by factor analysis method based on comprehensive evaluation of plant stress physiology.

СЕМЕННОЕ РАЗМНОЖЕНИЕ ФЛОКСА МЕТЕЛЬЧАТОГО (PHLOX PANICULATA L. ) В УСЛОВИЯХ ПЕРМСКОГО КРАЯ

During 2015-2018 in the conditions of the Perm region, the seed productivity of 6 varieties Phlox paniculata L. has been studied. The effectiveness of seed production and the success of seed propagation of the phlox depend on the weather conditions strongly, in particular on the air temperature and the amount of precipitation at the corresponding stages of plant development. This is determined by the activity of insect pollinators and effectiveness of pollination. In addition, the large variability of the studied indices in different flox cultivars is probably due to their complex hybrid nature, which reduces their reproductive abilities to varying degrees.

Status of Some Escaped Ornament Perennials in the Flora of Latvia

AbstractThis paper introduces eight ornamental perennial garden escapees that were recorded by the authors of this article on Lucavsala Island, Riga (Latvia) in 2016. Our data on Achillea ptarmica cv. ‘Boule de Neige’, Artemisia ludoviciana, Asclepias syriaca, Campanula lactiflora, Heliopsis helianthoides, Lathyrus latifolius, Phlox paniculata and Rudbeckia hirta contribute to the knowledge about the occurrence of these taxa in wild. All these species are also growing in the collection of ornamental perennials in the Botanical Garden of the University of Latvia. A review of these species in Latvian herbarium collections has been conducted. Five species, Heliopsis helianthoides, Artemisia ludoviciana, Campanula lactiflora, Lathyrus latifolius, Phlox paniculata, were observed for the first time outside cultivation forming relatively stable, reproducing populations. Two species, Achillea ptarmica multiplex cultivar and Rudbeckia hirta, were previously observed in seminatural habitats and, thus, considered as casual aliens at the naturalization stage. One of the species, Asclepias syriaca, was considered a new to Latvia casual alien species with high potential of invasiveness.

Development and Evaluation of Laboratory Bioassays to Study Powdery Mildew Pathogens of Phlox In Vitro.

The genus Phlox consists of approximately 65 species that include some of the most prevalent ornamental plants in the temperate zone. These popular ornamentals are extremely susceptible to powdery mildew (PM) caused by the biotrophic fungi Golovinomyces magnicellulatus and Podosphaera sp. In this study, we used Phlox paniculata and P. glaberrima to develop a set of laboratory tools to study these pathogens in vitro, including a detached leaf and a micropropagated plantlet bioassay. We assessed pathogen growth under different experimental conditions, which included the use of four different media variations (1/2 MS medium amended with benzimidazole and tetracycline), three ages of pathogen culture (14, 18, and 22 days), three phenological stages of the host tissue (1st, 3rd, and 5th node leaves), placement of inoculum on both leaf surfaces (abaxial and adaxial), and three different inoculation techniques (single spore transfer, colony tapping, colony brushing). Detached P. paniculata leaves were successfully maintained on benzimidazole-amended 1/2 MS medium for up to 3 weeks. For both pathogens, the use of 18-day-old cultures resulted in a higher number of larger, higher sporulating colonies compared with 1-4 and 22-day-old cultures. The adaxial side of 3rd node leaves supported statistically significant more fungal growth compared with the adaxial side of 1st and 5th node leaves. Both pathogens also successfully infected micropropagated plantlets of P. glaberrima. These newly developed tools should facilitate in vitro studies on PM of Phlox and possibly be applicable to other ornamental species attacked by the same fungi.

Pollen Morphology of Angiosperms of Central Nepal

Morphological structures of pollen-grains of fifteen species of angiosperms collected from Central Nepal were cytologically carried out. Pollen structure of fifteen species viz. Antirrhium majus from family Plantaginaceae, Brunfelsia pauciflora and Petunia hybrida from Solanaceae, Centurea cyanus and Chrysanthemum morifolium from Asteraceae, Malvaviscous arboreus from Malvaceae, Lantana camera from Verbenaceae, Chlorophytum comosum from Asperagaceae, Oxalis europia from Oxilidaceae, Jasminum officinale from Oleaceae, Geranium roseous from Geranaceae, Mirabilis jalapa from Nyctaginaceae, Phlox paniculata from Polymoniaceae and Tradescantia brivifolia from commelinaceae studied in this investigation. Most of the structure of pollen found to be spheroidal, some irregular, oval, elongated and circular. The present study gives an account of variations of pollen grain structure within the angiosperms family. Triporate to polyprate aperture and echinate to smooth walled exine were observed in present study. Pollen morphology of the angiosperm is significantly helpful at the generic and specific level in plant taxonomy.&#x0D; Int. J. Appl. Sci. Biotechnol. Vol 7(1): 102-107&#x0D;

Effect of Leaf Age and Cultivation under Shade Nets on the Ionome and Leaf Disorders in Phlox paniculata

Visual leaf damage symptoms affect plant and flower development. A variety of physiological leaf symptoms are induced by environmental and growing conditions, including light intensity during cultivation and the nutrition status of the leaves. In the present study, we studied effects of leaf age, leaf ionome, and shade factor during cultivation (20% and 47% shade – under shade nets), on the development of leaf disorders in two cultivars of Phlox paniculata. The leaf ionome of both cultivars changed with leaf age, and varied between cultivars. The percentage of shade applied during cultivation by shade nets, had a minor effect on the leaf ionome, and it did not affect the type and severity of the leaf disorders that developed on the plants, nor the stage of development of their appearance. The ionome of young leaves and mature leaves that were affected by a purple spotting disorder was similar to that of ‘healthy’-looking leaves, demonstrating that this disorder is not related to the nutritional status of the tissue. Our results further excluded leaf age, plant age, plant trimming and shade factor during cultivation (by shade nets) as inducers of the purple spots disorder. This study is first to explore the ionome of Phlox paniculata and in relation to leaf age, physiological leaf disorders and shade factor during cultivation.

Anaerobically Digested Dairy Fiber in Soilless Potting Media for Herbaceous Perennials

Sphagnum peat moss has been a primary component of soilless potting media for decades; however, concerns over the sustainability of harvesting peat have fostered a search for renewable media components. Anaerobically digested dairy fiber (ADDF), a by-product of methane production, shows promise as an alternative to peat. Herbaceous nursery crops including “Jack Frost” brunnera (Brunnera macrophylla I.M. Johnst), “Moonbeam” coreopsis (Coreopsis verticillata L.), “Whoops-a-Daisy” Shasta daisy (Leucanthemum × superbum Bergmans ex J.W. Ingram), “Kobold Original” liatris (Liatris spicata (L.) Willd.) and “David” phlox (Phlox paniculata L.) were grown in media containing bark-peat-perlite or bark-ADDF-perlite in a 4:2:1 proportion. All leachate was collected from pots to evaluate cumulative nitrogen and phosphate leaching. Brunnera grew to a similar size and quality in both mixes, although brunnera in the bark-ADDF-perlite mix had slightly chlorotic leaf margins. Coreopsis grew to a similar size and quality in both mixes but was slightly etiolated and chlorotic in bark-ADDF-perlite. Shasta daisy grown in bark-ADDF-perlite were larger than those grown in bark-peat-perlite. Both mixes produced similar growth and quality liatris and phlox. More ammonium, nitrate and phosphate were recovered from leachate from bark-ADDF-perlite than from bark-ADDF-perlite.

Relative Salt Tolerance of Seven Texas Superstar® Perennials

Salt tolerance of seven Texas Superstar® perennials [Malvaviscus arboreus var. drummondii (Turk’s cap), Phlox paniculata ‘John Fanick’ (‘John Fanick’ phlox), Phlox paniculata ‘Texas Pink’ (‘Texas Pink’ phlox), Ruellia brittoniana ‘Katie Blue’ (‘Katie Blue’ ruellia), Salvia farinacea ‘Henry Duelberg’ (‘Henry Duelberg’ salvia), Salvia leucantha (mexican bush sage), and Verbena ×hybrida ‘Blue Princess’ (‘Blue Princess’ verbena)] was evaluated in a greenhouse experiment. Plants were irrigated with a nutrient solution at electrical conductivity (EC) of 1.1 dS·m−1 (control) or a salt solution at EC of 5.0 or 10.0 dS·m−1 (EC 5 or EC 10) for 8 weeks. ‘John Fanick’ and ‘Texas Pink’ phlox plants in EC 5 had severe salt foliage damage, while those in EC 10 were died. Mexican bush sage in EC 10 had severe salt foliage damage. Turk’s cap, ‘Katie Blue’ ruellia, ‘Henry Duelberg’ salvia, and ‘Blue Princess’ verbena had minor foliar damage regardless of treatment. EC 5 reduced the shoot dry weight (DW) by 45% in ‘Texas Pink’ phlox and 11% to 18% in ‘Katie Blue’ ruellia, ‘Henry Duelberg’ salvia, and mexican bush sage, but did not impact the shoot DW of Turk’s cap and ‘John Fanick’ phlox. EC 10 further decreased the shoot DW of ‘Katie Blue’ ruellia, ‘Henry Duelberg’ salvia, and mexican bush sage plants by 32%, 29%, and 56%, respectively. EC 5 decreased leaf net photosynthesis (Pn) of ‘Texas Pink’ phlox and mexican bush sage, while EC 10 reduced Pn of all species except ‘Henry Duelberg’ salvia and ‘Blue Princess’ verbena. ‘Katie Blue’ ruellia and ‘Blue Princess’ verbena had relatively lower leaf Na concentration and ‘John Fanick’ phlox, ‘Texas Pink’phlox, and mexican bush sage had higher leaf Cl concentrations. In summary, Turk’s cap, ‘Katie Blue’ ruellia, ‘Henry Duelberg’ salvia, and ‘Blue Princess’ verbena were the most tolerant perennials, and ‘John Fanick’ phlox, ‘Texas Pink’ phlox, and mexican bush sage were the least tolerant to salinity.

Genome Size and Ploidy of Phlox paniculata and Related Germplasm in Subsections Paniculatae and Phlox

Phlox is an important genus of herbaceous ornamental plants previously targeted for germplasm development, characterization, and enhancement by the U.S. Department of Agriculture, National Plant Germplasm System. Among Phlox in cultivation, Phlox paniculata is the most widely grown and intensively bred species, but little is known about variation in genome size and ploidy of this species or of related taxa that may be used for germplasm enhancement. The objective of this study was to assess cytotype variation in a diverse collection of cultivars and wild germplasm of P. paniculata (subsection Paniculatae) and of related taxa in subsections Paniculatae and Phlox. The collection included 138 accessions from seven species and two interspecific hybrids. Flow cytometry was used to estimate holoploid (2C) genome sizes and to infer ploidy levels. Chromosome counts were made to calibrate ploidy with genome size for a subset of taxa. Most cultivars were diploid (2n = 2x = 14) and had mean genome sizes that did not vary between subsections Paniculatae (14.33 pg) and Phlox (14.23 pg) although size variation was greater among cultivars within subsection Phlox. Triploid cultivars of P. paniculata, with a mean genome size of 21.36 pg and mitotic chromosome counts of 2n = 3x = 21, were identified. Such triploids suggests previous interploid hybridization within this taxon. Five tetraploid (2n = 4x = 28) cultivars were found in subsection Phlox; all were selections of P. glaberrima ssp. triflora, and had a mean genome size of 25.44 pg; chromosome counts in one of these confirmed they were tetraploid. The putative hybrid Phlox Suffruticosa Group ‘Miss Lingard’ showed an intermediate genome size of 21.21 pg supporting a triploid, hybrid origin of this taxon. Mean 2C genome sizes among wild-collected accessions were similar to values reported for cultivars (Paniculatae = 14.59 pg, Phlox = 14.23 pg), but taxa in subsection Phlox exhibited greater variation that included two tetraploids identified among wild-collected accessions; one, of P. pulchra, had a mean genome size of 26.17 pg, representing the first report of polyploidy in the taxon. This is the first report on genome size for the majority of species in the study. Although genome size could not be used to differentiate taxa in subsections Paniculatae and Phlox, the data provide further insights into cytotype variation of Phlox germplasm useful for plant breeders and systematists.

Phytophthora nicotianae Can Cause Both Crown Rot and Foliage Blight on Phlox paniculata in South Carolina

Phytophthora nicotianae Can Cause Both Crown Rot and Foliage Blight on Phlox paniculata in South Carolina