Lobelia Cardinalis Research Articles

A Plant Model of α-Synucleinopathy: Expression of α-Synuclein A53T Variant in Hairy Root Cultures Leads to Proteostatic Stress and Dysregulation of Iron Metabolism.

Synucleinopathies, typified by Parkinson's disease (PD), entail the accumulation of α-synuclein (αSyn) aggregates in nerve cells. Various αSyn mutants, including the αSyn A53T variant linked to early-onset PD, increase the propensity for αSyn aggregate formation. In addition to disrupting protein homeostasis and inducing proteostatic stress, the aggregation of αSyn in PD is associated with an imbalance in iron metabolism, which increases the generation of reactive oxygen species and causes oxidative stress. This study explored the impact of αSyn A53T expression in transgenic hairy roots of four medicinal plants (Lobelia cardinalis, Artemisia annua, Salvia miltiorrhiza, and Polygonum multiflorum). In all tested plants, αSyn A53T expression triggered proteotoxic stress and perturbed iron homeostasis, mirroring the molecular profile observed in human and animal nerve cells. In addition to the common eukaryotic defense mechanisms against proteostatic and oxidative stresses, a plant stress response generally includes the biosynthesis of a diverse set of protective secondary metabolites. Therefore, the hairy root cultures expressing αSyn A53T offer a platform for identifying secondary metabolites that can ameliorate the effects of αSyn, thereby aiding in the development of possible PD treatments and/or treatments of synucleinopathies.

An efficient method for economic micropropagation of three aquatic plant species (Lobelia cardinalis, Staurogyne repens, and Alternanthera reineckii)

An efficient method for economic micropropagation of three aquatic plant species (Lobelia cardinalis, Staurogyne repens, and Alternanthera reineckii)

Organogenesis and efficient in vitro plantlet regeneration from nodal segments of an ornamental aquatic plant,Lobelia cardinalisL., using BAP

ISHS IX International Scientific and Practical Conference on Biotechnology as an Instrument for Plant Biodiversity Conservation (physiological, biochemical, embryological, genetic and legal aspects) Organogenesis and efficient in vitro plantlet regeneration from nodal segments of an ornamental aquatic plant, Lobelia cardinalis L., using BAP

Microfluidic capillary zone electrophoresis mass spectrometry analysis of alkaloids in Lobelia cardinalis transgenic and mutant plant cell cultures.

Application of a microfluidic CE* device for CZE-MS allows for fast, rapid, and in-depth analysis of large sample sets. This microfluidic CZE-MS device, the 908 Devices ZipChip, involves minimal sample preparation and is ideal for small cation analytes, such as alkaloids. Here, we evaluated the microfluidic device for the analysis of alkaloids from Lobelia cardinalis hairy root cultures. Extracts from wild-type, transgenic, and selected mutant plant cultures were analyzed and data batch processed using the mass spectral processing software MZmine2 and the statistical software Prism 8. In total 139 features were detected as baseline resolved peaks via the MZmine2 software optimized for the electrophoretic separations. Statistically significant differences in the relative abundance of the primary alkaloid lobinaline (C27 H34 N2 ), along with several putative "lobinaline-like" molecules were observed utilizing this approach. Additionally, a method for performing both targeted and untargeted MS/MS experiments using the microfluidic device was developed and evaluated. Coupling data-processing software with CZE-MS data acquisition has enabled comprehensive metabolomic profiles from plant cell cultures to be constructed within a single working day.

The rhizosphere of aquatic plants is a habitat for cable bacteria.

ABSTRACTCable bacteria belonging to the family Desulfobulbaceae couple sulfide oxidation and oxygen reduction by long-distance electron transfer over centimeter distances in marine and freshwater sediments. In such habitats, aquatic plants can release oxygen into the rhizosphere. Hence, the rhizosphere constitutes an ideal habitat for cable bacteria, which have been reported on seagrass roots recently. Here, we employ experimental approaches to investigate activity, abundance, and spatial orientation of cable bacteria next to the roots of the freshwater plant Littorella uniflora. Fluorescence in situ hybridization (FISH), in combination with oxygen-sensitive planar optodes, demonstrated that cable bacteria densities are enriched at the oxic–anoxic transition zone next to roots compared to the bulk sediment in the same depth. Scanning electron microscopy showed cable bacteria along root hairs. Electric potential measurements showed a lateral electric field over centimeters from the roots, indicating cable bacteria activity. In addition, FISH revealed that cable bacteria were present in the rhizosphere of Oryza sativa (rice), Lobelia cardinalis and Salicornia europaea. Hence, the interaction of cable bacteria with aquatic plants of different growth forms and habitats indicates that the plant root–cable bacteria interaction might be a common property of aquatic plant rhizospheres.

Greenhouse Culture and Production of Four Ornamental Native Wetland Plants

Wetland restoration is an important way to improve ecosystem services, but many wetland nurseries lack the facilities that are traditionally used to produce large numbers of native plants used in these projects. Our goal was to evaluate growth and performance of four wetland species in a variety of substrates, fertilizer regimes, and irrigation methods under greenhouse conditions. Plants were grown in pots with drainage holes filled with one of four substrates (potting substrate, topsoil, sand, 50/50 mix of topsoil, and sand) amended with 0, 1, 2, or 4 g of 15N–3.9P–10K controlled-release fertilizer per liter of substrate. Irrigation was supplied via an overhead system or subirrigation. After 16 weeks of production, plants were scored for visual quality and plant height before a destructive harvest. Broadleaf sagittaria (Sagittaria latifolia) was mostly unaffected by substrate type but performed best when subirrigated and fertilized with 4 g·L−1 of fertilizer. Growth of skyflower (Hydrolea corymbosa) and cardinal flower (Lobelia cardinalis) was best when fertilized with 2 or 4 g·L−1 of fertilizer and grown using overhead irrigation. String lily (Crinum americanum) was unaffected by substrate type but produced the largest plants when subirrigated. These experiments provide guidance for cultivating these wetland species under greenhouse conditions, which may allow growers to efficiently produce plant material needed for the restoration market.

First Report of Cercospora apii s. lat. Causing a Leaf Spot on Cardinal Flower (Lobelia cardinalis) in the United States

Cardinal flower (Lobelia cardinalis L.: Campanulaceae) is a wildflower common throughout much of the eastern United States and grows in a variety of habitats. It is used as an ornamental plant because its bright red flowers appear in the fall and attract hummingbirds. The foliage is generally free of disease when the plant is not flowering, although a few leaf and stem lesions may be present during the growing season. In August/September 2016 and 2017, plants established in eastern Tennessee developed numerous spots on stems and leaves. The round- to lenticular-shaped lesions had dry, white, papery necrotic centers surrounded by reddish-purple host tissue. There were no signs of a pathogen. Leaves were washed in running water for 5 min, surface disinfested with 1.05% NaClO for 15 min, and rinsed three times in sterile water. Lesions and some green tissue from leaves were transferred to half-strength potato dextrose agar (PDA) augmented with 10 mg rifampicin/liter, and incubated in the dark. Mycelium was i...

A faster inoculation assay for Armillaria using herbaceous plants

ABSTRACTArmillaria (honey fungus) is a virulent necrotrophic pathogen that causes Armillaria root disease. Conventional Armillaria inoculation assays use young saplings as hosts and consequently are cumbersome, frequently conducted outdoors, and take many years from establishment to analysis of infection. We have developed and evaluated a faster inoculation assay for Armillaria that uses herbaceous plants as hosts, is carried out in controlled conditions, and reduces experimental durations to 3 months. Plant species of known susceptibility to Armillaria and comparisons between virulent A. mellea and opportunistic A. gallica were used to validate the assay. Mortality and diagnostic symptoms of Armillaria root disease such as epiphytic rhizomorphs and mycelial fans were used to assess levels of infection. We also attempted to reduce assay preparation time by substituting woody inocula with agar inocula, but typical symptoms of Armillaria root disease were only observed on plants infected with woody inocula. Through our assay, we identified five new potential herbaceous hosts of Armillaria: Kniphofia hirsuta, Hordeum vulgare, Lobelia cardinalis, Nicotiana tabacum and Helenium hoopesii – further expanding the extensive list of plants with susceptibility to Armillaria and suggesting infection of herbaceous species may be more widespread than currently acknowledged.

Novel multifunctional pharmacology of lobinaline, the major alkaloid from Lobelia cardinalis

In screening a library of plant extracts from ~1000 species native to the Southeastern United States, Lobelia cardinalis was identified as containing nicotinic acetylcholine receptor (nicAchR) binding activity which was relatively non-selective for the α4β2- and α7-nicAchR subtypes. This nicAchR binding profile is atypical for plant-derived nicAchR ligands, the majority of which are highly selective for α4β2-nicAchRs. Its potential therapeutic relevance is noteworthy since agonism of α4β2- and α7-nicAchRs is associated with anti-inflammatory and neuroprotective properties. Bioassay-guided fractionation of L. cardinalis extracts led to the identification of lobinaline, a complex binitrogenous alkaloid, as the main source of the unique nicAchR binding profile. Purified lobinaline was a potent free radical scavenger, displayed similar binding affinity at α4β2- and α7-nicAchRs, exhibited agonist activity at nicAchRs in SH-SY5Y cells, and inhibited [3H]-dopamine (DA) uptake in rat striatal synaptosomes. Lobinaline significantly increased fractional [3H] release from superfused rat striatal slices preloaded with [3H]-DA, an effect that was inhibited by the non-selective nicAchR antagonist mecamylamine. In vivo electrochemical studies in urethane-anesthetized rats demonstrated that lobinaline locally applied in the striatum significantly prolonged clearance of exogenous DA by the dopamine transporter (DAT). In contrast, lobeline, the most thoroughly investigated Lobelia alkaloid, is an α4β2-nicAchR antagonist, a poor free radical scavenger, and is a less potent DAT inhibitor. These previously unreported multifunctional effects of lobinaline make it of interest as a lead to develop therapeutics for neuropathological disorders that involve free radical generation, cholinergic, and dopaminergic neurotransmission. These include neurodegenerative conditions, such as Parkinson's disease, and drug abuse.

Morphological and Physiological Responses of Nine Ornamental Species to Saline Irrigation Water

To provide more species for landscapes where poor-quality irrigation water is used, salt tolerance of commonly used landscape plants should be characterized. Nine ornamental species, including six herbaceous and three woody, were irrigated with nutrient solution at electrical conductivity (EC) of 1.2 dS·m−1 (control) or saline solution at EC of 5.0 or 10.0 dS·m−1 (EC 5 or EC 10) for 8 weeks and their growth and physiological responses were determined. Although growth was reduced in orange peel jessamine (Cestrum ‘Orange Peel’) and mexican hummingbird bush (Dicliptera suberecta) as salinity increased, no obvious signs of stress or injury were observed, indicating that orange peel jessamine and mexican hummingbird bush were the most salt tolerant. Flame acanthus (Anisacanthus quadrifidus var. wrightii), rock rose (Pavonia lasiopetala), and ‘Dark knight’ bluebeard (Caryopteris ×clandonensis ‘Dark Knight’) had more growth reduction than that of orange peel jessamine and mexican hummingbird bush with minimal or no foliar damage in EC 5 and slight foliar damage in EC 10. Cardinal flower (Lobelia cardinalis) and mexican false heather (Cuphea hyssopifolia) exhibited mortality rates of 30% and 20%, severe foliar damage, and greater than 70% reduction in leaf area and dry weight in EC 10 compared with their respective controls. Although the growth reductions in butterfly blue (Scabiosa columbaria) were not as great as cardinal flower and mexican false heather, 40% of butterfly blue plants were dead with moderate foliar damage in EC 10. Therefore, cardinal flower, mexican false heather, and butterfly blue plants were considered as moderately salt sensitive. Eastern red columbine (Aquilegia canadensis) was the most salt sensitive among the species investigated with moderate foliar damage in EC 5 and all plants died in EC 10. Four out of the nine species tested had significant differences in net photosynthetic rate (Pn), stomatal conductance (gs), and/or relative chlorophyll content between the control and EC 10, and the difference varied with species. Shoot ion concentrations of the nine ornamentals were also affected by salinity levels and varied among species.

Native Aquatic and Wetland Plants: Cardinal Flower, Lobelia cardinalis

This 3-page fact sheet discusses the classification, description, habitat, propagation, and use of cardinal flower, an aquatic perennial that is commonly found in stream banks and swamps. Written by Kimberly A. Moore, Luci E. Fisher, Carl J. Della Torre III, and Lyn A. Gettys, and published by the UF Department of Agronomy, December 2015. SS-AGR-398/AG402: Native Aquatic and Wetland Plants: Cardinal Flower, Lobelia cardinalis (ufl.edu)

The sexual neighborhood through time: competition and facilitation for pollination in Lobelia cardinalis.

Reproductive success in flowering plants is influenced by the morphology and timing of reproductive structures as well as the density of surrounding conspecifics. In species with separate male and female flower phases, successful pollen transfer is also expected to vary with the density and ratio of surrounding male and female flowers. Increased density of surrounding flowers may increase pollinator visitation rates, but the densities of male and female flowers will determine the availability of pollen and the strength of competition for pollen receipt. Here we (1) quantify the influence of surrounding plant density on total seasonal fruit and seed production, (2) quantify the influence of sexual neighborhood (surrounding sex ratio and densities of male- and female-phase flowers) on fruit and seed production for individual flowers presented within the season, and (3) compare the influence of plant density on fitness to that of focal plant phenotype, specifically stigma-nectary distance and plant height, in a natural population of the pollen-limited, hummingbird-pollinated hermaphrodite Lobelia cardinalis. These relationships were examined at four spatial scales (10, 20, 50, and 100 cm). By examining temporal and spatial scales we found that (1) total seed production per plant decreased with increasing plant density at the smallest scale but increased with increasing density at all larger scales; (2) at any given time, a female-phase flower benefited from a higher density of surrounding male-phase flowers and a lower density of surrounding female-phase flowers; (3) when sex ratio was explicitly analyzed, a female-phase flower benefited from a lower proportion of surrounding female flowers as well as a lower total flower density; and (4) at the whole-plant level, taller plants were more likely to produce fruit (even when accounting for total number of flowers produced), consistent with pollinator preference for taller floral displays. Our results suggest that the local density of male and female flowers (and surrounding sex ratio) influences successful pollen transfer, implying that the local floral environment may shape how attraction traits like plant height are related to fitness.

Radial Oxygen Loss in Wetland Plants: Potential Impacts on Remediation of Contaminated Sediments

AbstractRemediation of sediments contaminated with persistent organic compounds such as polycyclic aromatic hydrocarbons has been problematic due to the lack of oxygen in saturated sediments. Certain wetland plants have the potential to create aerobic conditions in the anoxic sediments through radial oxygen loss into the rhizosphere. The objective of the current study was to utilize several methods of measuring radial oxygen loss to identify wetland species with relatively high rates of oxygen loss into the rhizosphere. The results show clearly that there are significant differences between plant species in terms of radial oxygen loss. Rates in the current study ranged from 0 cm2 (Lobelia cardinalis) oxygenated to 56 cm2 (Sagittaria latifolia). In addition, the three methods of measuring radial oxygen loss showed consistency in the high radial oxygen loss species, but we found that the methylene blue agar method was more sensitive in detecting differences between species and also enabled visualization o...

Differences in the structure of anthocyanins from the two amphibious plants, Lobelia cardinalis and Nesaea crassicaulis

The foliar anthocyanin profiles of two amphibious plants, Nesaea crassicaulis and Lobelia cardinalis were analysed for the first time. N. crassicaulis produced very simple anthocyanins, achieving the highest concentrations when grown submerged. In contrast, L. cardinalis produced leaves with a high content of very complex, acylated anthocyanins, especially when growing emergent. Anthocyanins were separated by high performance liquid chromatography. Nesaea crassicaulis anthocyanins were identified according to their fragment mass spectra and ultra-visible-violet spectral characteristics and 1D and 2D NMR spectra as -3,5-di-O-β-glucosides of delphinidin, cyanidin, petunidin, malvidin and peonidin as well as cyanidine and peonidin-3-O-β-glucoside. In L. cardinalis cyanidin-3-O-[6-O-(4-O-E-p-coumaroyl-O-α-rhamnopyranosyl)-β-glucopyrano]-5-O-β-glucopyranoside was the major anthocyanin and contributed more than 98% of total anthocyanin content. The remaining 2% was made up by cyanidin-3-O-[6-O-(4-O-E-caffeoyl-O-α-rhamnopyranosyl)-β-glucopyrano]-5-O-β-glucopyranoside and pelargonidin-3-O-[6-O-(4-O-E-p-coumaroyl-O-α-rhamnopyranosyl)-β-glucopyrano]-5-O-β-glucopyranoside.

Pollinators cause stronger selection than herbivores on floral traits inLobelia cardinalis(Lobeliaceae)

Measures of selection on floral traits in flowering plants are often motivated by the assumption that pollinators cause selection. Flowering plants experience selection from other sources, including herbivores, which may enhance or oppose selection by pollinators. Surprisingly, few studies have examined selection from multiple sources on the same traits. We quantified pollinator-mediated selection on six floral traits of Lobelia cardinalis by comparing selection in naturally and supplementally (hand-) pollinated plants. Directional, quadratic and correlational selection gradients as well as total directional and quadratic selection differentials were examined. We used path analysis to examine how three herbivores--slugs, weevils and caterpillars--affected the relationship between floral traits and fitness. We detected stronger total selection on four traits and correlational selection (γ(ij)) on three trait combinations in the natural pollination treatment, indicating that pollinators caused selection on these traits. Weak but statistically significant selection was caused by weevil larvae on stem diameter and anther-nectary distance, and by slugs on median-flower date. In this study, pollinators imposed stronger selection than herbivores on floral traits in L. cardinalis. In general, the degree of pollen limitation and rate of herbivory are expected to influence the relative strength of selection caused by pollinators or herbivores.

Plant waterworld

Plant waterworld

Progress in the detection of costs of phenotypic plasticity in plants

Progress in the detection of costs of phenotypic plasticity in plants

From horticultural plantings into wild populations: movement of pollen and genes in Lobelia cardinalis

Understanding the potential movement of genes from horticultural plantings into conspecific wild populations requires fundamental knowledge of pollen flow distances and of the siring abilities of genetically differentiated pollen types on local plants. We addressed these issues using Lobelia cardinalis, a native, hummingbird-pollinated species, which is available horticulturally both as wild types and cultivated varieties. Potential pollen and gene flow between relatively isolated populations were measured in an artificial array experiment. Potted plants were placed at discrete distances (50, 100, 500, and 1000 m) from either a local or one of three non-local potted pollen sources and scored for pollen and gene flow. Pollen movement was assessed with a dye analogue. The pollen source population did not significantly influence the results, but dye movement, fruit set, and to a lesser degree fruit volume declined with distance from the pollen source. Even at 1 km away from the pollen source, 20–50% of flowers set fruit, indicating substantial gene movement. Siring ability of four non-local pollen types on local plants was assessed by comparing paternity success when each type comprised 75, 50, and 25% of the pollen in controlled mixed load pollinations. Pollen type affected the percentage of non-local offspring. A cultivated variety of L. cardinalis showed poor siring success on the Virginia maternal plants at all mix ratios. Mating was random in mixes with Virginia pollen and pollen from geographically distant wild-type varieties. Finally, pollen from a neighboring county was significantly favored over local sires. These results demonstrate that pollen movement from horticultural plantings into native populations and the production of hybrid seed on native plants is possible in L. cardinalis.

Growth, Gas Exchange, and Chlorophyll Fluorescence of Four Ornamental Herbaceous Perennials during Water Deficit Conditions

A study was conducted to characterize the morphological and physiological responses of four herbaceous perennial species subjected to two subsequent drought cycles. Lantana camara L. `New Gold' (lantana), Lobelia cardinalis L. (cardinal flower), Salvia farinacea Benth. `Henry Duelberg' (mealy sage), and Scaevola aemula R. Br. `New Wonder' (fan flower) were subjected to two consecutive 10-day drought cycles. Growth response, leaf gas exchange, and chlorophyll fluorescence were measured during the experiment. The morphology of L. cardinalis and L. camara was not affected by drought, while S. farinacea had reductions in plant height and leaf area and S. aemula had reductions in dry weight. Overall, plant growth and development continued even when substrate water content was reduced to 0.13 mm3·mm-3, which indicated a level of substrate water below container capacity was sufficient for greenhouse production of these species. The drought treatments had little effect on the photochemical efficiency (Fv/Fm) of Photosystem II. An increase in minimal fluorescence (Fo) was observed in S. aemula on the last day of the second cycle. Drought treatment caused increased leaf-level water use efficiency (WUE) at the end of the first cycle in L. cardinalis and S. aemula, but not in L. camara and S. farinacea. Plants of L. camara, S. farinacea, and S. aemula that had received drought during both cycles became more water use efficient by the end of the second cycle, but L. cardinalis did not.

PLASTICITY OF PHYSIOOLGY INLOBELIA: TESTING FOR ADAPTATION AND CONSTRAINT

Phenotypic plasticity is thought to be a major mechanism allowing sessile organisms such as plants to adapt to environmental heterogeneity. However, the adaptive value of many common plastic responses has not been tested by linking these responses to fitness. Even when plasticity is adaptive, costs of plasticity, such as the energy necessary to maintain regulatory pathways for plastic responses, may constrain its evolution. We used a greenhouse experiment to test whether plastic physiological responses to soil water availability (wet vs. dry conditions) were adaptive and/or costly in the congeneric wildflowers Lobelia cardinalis and L. siphilitica. Eight physiological traits related to carbon and water uptake were measured. Specific leaf area (SLA), photosynthetic rate (A), stomatal conductance (gs), and photosynthetic capacity (Amax) responded plastically to soil water availability in L. cardinalis. Plasticity in Amax was maladaptive, plasticity in A and g(s) was adaptive, and plasticity in SLA was adaptively neutral. The nature of adaptive plasticity in L. cardinalis, however, differed from previous studies. Lobelia cardinalis plants with more conservative water use, characterized by lower g(s), did not have higher fitness under drought conditions. Instead, well-watered L. cardinalis that had higher g(s) had higher fitness. Only Amax responded plastically to drought in L. siphilitica, and this response was adaptively neutral. We detected no costs of plasticity for any physiological trait in either L. cardinalis or L. siphilitica, suggesting that the evolution of plasticity in these traits would not be constrained by costs. Physiological responses to drought in plants are presumed to be adaptive, but our data suggest that much of this plasticity can be adaptively neutral or maladaptive.