Glyphosate Toxicity to Native Nontarget Macrophytes Following Three Different Routes of Incidental Exposure.

A major goal of invasive plant management is the restoration of native biodiversity, but effective methods for invasive plant control can be harmful to native plants. Informed application of control methods is required to reach restoration goals. The herbicide glyphosate, commonly applied in invasive plant management, can be toxic to native macrophytes.

The effects of triclosan on spore germination and hyphal growth of the arbuscular mycorrhizal fungus Glomus intraradices.

The effect of triclosan (5-chloro-2-[2,4-dichlorophenoxy]phenol; TCS), on spore germination, hyphal growth, and hyphal branching of the arbuscular mycorrhizal (AM) fungus, Glomus intraradices spores was evaluated at exposure concentrations of 0.4 and 4.0 μg/L in a static renewal exposure system.

Triclosan inhibits arbuscular mycorrhizal colonization in three wetland plants.

In terrestrial ecosystems, plant growth, plant community structure, and ultimately the ecosystem services provided by plants are dependent on the presence and composition of below ground arbuscular mycorrhizal (AM) fungal communities. AM fungi form obligate symbioses with plants providing nutrients to their host plants in exchange for photosynthates. While AM have been found in most wetland ecosystems, the effects of urban contaminants on AM associations are largely unknown.

Bioconcentration of triclosan, methyl-triclosan, and triclocarban in the plants and sediments of a constructed wetland.

Constructed wetlands are a potential method for the removal of two pharmaceutical and personal care products from wastewater effluent. Triclosan (TCS; 5-chloro-2-[2,4-dichlorophenoxy]phenol) and triclocarban (TCC; 3,4,4'-trichlorocarbanillide) are antimicrobial agents added to a variety of consumer products whose accumulation patterns in constructed wetlands are poorly understood. Here, we report the accumulation of TCS, its metabolite methyl-triclosan (MTCS; 5-chloro-2-[2,4-dichlorophenoxy]), and TCC in wetland plant tissues and sediments.

Effects of arbuscular mycorrhizal fungi on seedling growth and development of two wetland plants, Bidens frondosa L., and Eclipta prostrata (L.) L., grown under three levels of water availability.

To identify the importance of arbuscular mycorrhizal fungi (AMF) colonizing wetland seedlings following flooding, we assessed the effects of AMF on seedling establishment of two pioneer species, Bidens frondosa and Eclipta prostrata grown under three levels of water availability and ask: (1) Do inoculated seedlings differ in growth and development from non-inoculated plants? (2) Are the effects of inoculation and degree of colonization dependent on water availability? (3) Do plant responses to inoculation differ between two closely related species? Inoculation had no detectable effects on shoot height, or plant biomass but did affect biomass partitioning and root morphology in a species-specific manner. Shoot/root ratios were significantly lower in non-inoculated E. prostrata plants compared with inoculated plants (0.

Real-time TEM and kinetic Monte Carlo studies of the coalescence of decahedral gold nanoparticles.

We report on a real-time in situ TEM study of the coalescence of individual pairs of decahedral gold nanoparticles, which have been synthesized in solution. We observe the rate of growth of the neck that joins two particles during coalescence and compare this to classical continuum theory and to atomistic kinetic Monte Carlo simulations. We find good agreement between the observations and the simulations but not with the classical continuum model.

Effects of triclosan on seed germination and seedling development of three wetland plants: Sesbania herbacea, Eclipta prostrata, and Bidens frondosa.

Three wetland macrophytes, Sesbania herbacea, Bidens frondosa, and Eclipta prostrata, were exposed (0.4-1,000-ppb nominal concentrations) to the antimicrobial triclosan for 28 d in a flow-through system. Sesbania herbacea had decreased seed germination at the 100-ppb exposure level at days 7, 14, and 21, and B.

A re-examination of the root cortex in wetland flowering plants with respect to aerenchyma.

Aims: We review literature and present new observations on the differences among three general patterns of aerenchyma origin and their systematic distributions among the flowering plants, and we clarify terminology on root aerenchyma.

Scope: From our own previous works and some new observations, we have analysed the root cortex in 85 species of 41 families in 21 orders of flowering plants that typically grow in wetlands to determine the characteristic patterns of aerenchyma.

Findings: A developmental and structural pattern that we term expansigeny, as manifested by honeycomb aerenchyma, is characteristic of all aquatic basal angiosperms (the Nymphaeales) and basal monocots (the Acorales).

The aerenchymatous phellem of Lythrum salicaria (L.): a pathway for gas transport and its role in flood tolerance.

While the importance of cortical aerenchyma in flood tolerance is well established, this pathway for gaseous exchange is often destroyed during secondary growth. For woody species, therefore, an additional pathway must develop for oxygen to reach submerged tissues. In this paper we examine the potential for the aerenchymatous phellem (cork) of Lythrum salicaria L.