A model is presented of the regulation of ethylene biosynthesis in relation to submergence and flooding resistance. It is based on time-course measurements of ethylene production, ethylene accumulation, and concentrations of free and conjugated 1-aminocyclo-propane-1-carboxylic acid (ACC) in submerged and drained flooding-resistant Rumex palustris Sm. and flooding-sensitive Rumex acetosella L. ...

A model i s presented of the regulation of ethylene biosynthesis in relation to submergence and flooding resistance. It i s based on t ime-come measurements of ethylene production, ethylene accumulation, and concentrations of free and conjugated 1 -aminocyclopropane-1 -carboxylic acid (ACC) in submerged and drained flooding-resistant Rumex palusfris Sm. and flooding-sensitive Rumex acefosella 1...

Submergence-induced ethylene synthesis and entrapment were studied in two contrasting Rumex species, one flood-resistant (Rumex palustris) and the other flood-sensitive (Rumex acetosa). The application of a photoacoustic method to determine internal ethylene concentrations in submerged plants is discussed. A comparison with an older technique (vacuum extraction) is described. For the first time...

Rumex palustris responds to complete submergence with upward movement of the younger petioles. This so-called hyponastic response, in combination with stimulated petiole elongation, brings the leaf blade above the water surface and restores contact with the atmosphere. We made a detailed study of this differential growth process, encompassing the complete range of the known signal transduction ...

An experimental investigation is reported of the unsteady forces d ue to heaving motion of fully wetted hydrofoils of unity aspect ratio and also in two-dimensiona l flow. The tests covered a broad range of reduced frequency and determined the effects of variation in submergence depth, angle of attack, oscillation amplitude, and flow velocity. In genera l, the findings agree well with available...

BACKGROUND AND AIMS Anaerobic or low oxygen conditions occur when maize plants are submerged or subjected to flooding of the soil. Maize survival under low oxygen conditions is largely dependent on metabolic, physiological and morphological adaptation strategies; the regulation mechanisms of which remain unknown. MicroRNAs (miRNAs) play critical roles in the response to adverse biotic or abioti...

BACKGROUND AND AIMS Complete submergence is an important stress factor for many terrestrial plants, and a limited number of species have evolved mechanisms to deal with these conditions. Rumex palustris is one such species and manages to outgrow the water, and thus restore contact with the atmosphere, through upward leaf growth (hyponasty) followed by strongly enhanced petiole elongation. These...

Recurrent water level fluctuation and submergence of plants are common in riparian zones. Our study objectives were to test the independent and interactive effects of submergence level and fluctuation frequency on a globally important riparian invasive plant, Alternanthera philoxeroides. To this end, we conducted a greenhouse experiment, in which ramets of the plants, obtained from a wetland in...

Classes of vortex formation from a horizontal cylinder adjacent to an undulating free-surface wave are characterized using high-image-density particle image velocimetry. Instantaneous representations of the velocity "eld, streamline topology and vorticity patterns yield insight into the origin of unsteady loading of the cylinder. For su$ciently deep submergence of the cylinder, the orbital natu...