Low nitrate under waterlogging triggers exodermal suberization to form a barrier to radial oxygen loss in rice roots.

To acclimate to hypoxic waterlogged conditions, the roots of wetland plants form a radial oxygen loss (ROL) barrier that can promote oxygen diffusion to the root tips. We hypothesized that the low-nitrate concentrations that occur after molecular oxygen is consumed in waterlogged soils are an environmental trigger for ROL barrier formation in rice (Oryza sativa). We previously identified 128 tissue-specific up/downregulated genes during rice ROL barrier formation.

Exogenous abscisic acid induces the formation of a suberized barrier to radial oxygen loss in adventitious roots of barley (Hordeum vulgare).

Background And Aims: Internal root aeration is essential for root growth in waterlogged conditions. Aerenchyma provides a path for oxygen to diffuse to the roots. In most wetland species, including rice, a barrier to radial oxygen loss (ROL) allows more of the oxygen to diffuse to the root tip, enabling root growth into anoxic soil.

Imaging the snorkel effect during submerged germination in rice: Oxygen supply via the coleoptile triggers seminal root emergence underwater.

Submergence during germination impedes aerobic metabolisms and limits the growth of most higher plants. However, some wetland plants including rice can germinate under submerged conditions. It has long been hypothesized that the first elongating shoot tissue, the coleoptile, acts as a snorkel to acquire atmospheric oxygen (O) to initiate the first leaf elongation and seminal root emergence.

Imaging of Plant Hormones with Nanoparticle-Assisted Laser Desorption/Ionization Mass Spectrometry.

Plant hormones can act in synergistic and antagonistic ways in response to biotic and abiotic stresses and during plant growth and development. Thus, a technique is needed to simultaneously determine the distribution and concentration of several plant hormones. A relatively new technology, mass spectrometry imaging (MSI), enables the direct mapping and imaging of biomolecules on tissue sections.

Abscisic acid is required for exodermal suberization to form a barrier to radial oxygen loss in the adventitious roots of rice (Oryza sativa).

To acclimate to waterlogged conditions, wetland plants form a barrier to radial oxygen loss (ROL) that can enhance oxygen transport to the root apex. We hypothesized that one or more hormones are involved in the induction of the barrier and searched for such hormones in rice. We previously identified 98 genes that were tissue-specifically upregulated during ROL barrier formation in rice.