Phytoscale Transport Physics: Insights into Xylem Flow Homeostasis and Drought Stress

Jinmay Kalita; Sumit Kumar Mehta; Suraj Panja; Pranab Kumar Mondal

Home/Archive/arXiv

arXiv · 2511.23303

Phytoscale Transport Physics: Insights into Xylem Flow Homeostasis and Drought Stress

Jinmay Kalita·Sumit Kumar Mehta·Suraj Panja·Pranab Kumar Mondal

View original source ↗Read source document ↗Export metadata ↓

Abstract

We investigate the flow dynamics of nutrient solution through the xylem vessels of Brassica juncea under drought stress. To this end, we perform experiments to obtain morphological traits of xylem vessels under drought-stressed conditions, and develop a mathematical framework to model the underlying flow through the xylem, considering several features relevant to the plant system. Performing experiments using state of the art instruments, we measure the morphology of xylem vessels, physicochemical and mechanical properties of xylem walls under drought stressed conditions. Our experimental results unveil that drought reduces both xylem diameter and pit aperture size, implicating hydraulic adaptations of plants to drought stress. We find that the reduced cellulose content in drought stressed xylem vessels lowers the zeta potential and decreases elasticity of the vascular region. Additionally, drought stress alters metabolite activity, increases reactive oxygen species, reduces chlorophyll content, and limits the uptake of essential metallic nutrients. Besides, we perform three-dimensional numerical simulations to evaluate local flow field, mechanical stress, hydraulic conductivity, and radial transport efficiency of xylem vessels under drought stressed conditions. Simulated results reveal that under drought conditions, resistance to axial flow through xylem vessels increases significantly, which in turn, promotes radial transport of nutrients, allowing plants to survive even in drought stress. We show that the radial flow efficiency of xylem vessels becomes notably higher under drought stress than in well-watered control plants. Overall, results of this endeavor provide new insights into how geometric adaptations of xylem vessels modify flow behavior under water deficient conditions, enhancing the plants ability to survive environmental stress.

Explore related subjects

physics.bio-ph physics.flu-dyn

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

Jinmay Kalita, Sumit Kumar Mehta, Suraj Panja, Pranab Kumar Mondal. 2025-11-28. Phytoscale Transport Physics: Insights into Xylem Flow Homeostasis and Drought Stress. https://arxiv.org/abs/2511.23303

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Biology and Physics

This article frames the relation between biology and physics by characterizing the former as a subdiscipline rather than a special case of the latter. To do this, we posit biological physics as the science of living matter in contrast to classic biophysics, the study of organismal properties by physical techniques. At the scale of the individual cell, living matter is nonunitary, i.e., not composed of aggregated subunits, and has features (e.g., intracellular organizational arrangements and biomolecular condensates) that are unlike any materials of the nonliving world. In transiently or constitutively multicellular forms (social microorganisms, animals, plants), living matter sustains physical processes that are generic (shared with nonliving matter, e.g., subunit communication by molecular diffusion in cellular slime molds), biogeneric (analogous to nonliving matter but realized through cellular activities, e.g., subunit demixing in animal embryos) or nongeneric (pertaining to sui generis materials, e.g., budding of active solids in plants). This "forms of matter" perspective is philosophically situated in the dialectical materialism of Engels and Hessen and the multilevel physicalism of Neurath and the logical empiricists. We counterpose this view to informationism and to genetic and other hierarchically reductionist physical theories of biological systems and highlight open questions regarding incompletely characterized and enigmatic forms of living matter.

physics.bio-ph↗

arXiv2026

Stabilizing by steering: Enhancing bacterial motility by non-uniform diffusiophoresis

Bacteria often traverse confined spaces to perform critical functions in symbiosis, infection, drug delivery, and soil bioremediation. While the canonical run-and-tumble strategy enables exploration, its reliance on stochastic reorientation limits efficiency under confinement. We show that salt gradients can physically steer Pseudomonas putida by biasing their runs toward salt through asymmetric diffusiophoretic forces. These gradients impose a torque strong enough to overcome Brownian rotation, aligning cells along the gradient and producing straighter, more persistent motion. This response persists in a Δ{cheA} mutant, demonstrating that canonical CheA-dependent chemotaxis is not required. We further show that when toxic organic contaminants are present, salt gradients promote bacterial dispersion toward the source despite reduced motility, suggesting potential applications in bacterial delivery for bioremediation. This work uncovers a previously unrecognized mechanism by which salt gradients direct bacterial motility, revealing a physical route to control microbial transport in complex environments.

physics.bio-ph↗

arXiv2026

Signature of mechanically induced cell extrusions in cell size distribution

How a growing tissue organizes its own homeostatic state is a central question in the physics of living matter. We show that when a growing epithelial sheet counteracts increasing cell density by mechanically squeezing cells out of its plane, a homeostatic in-plane pressure emerges as a generalization of a yield stress. We find that in the quasistatic growth limit the homeostatic state is marginally stable, with a pseudogap in the distribution of local distances to the extrusion threshold pressure. Because such mechanically induced extrusions arise from an instability of individual cells, the pseudogap is imprinted in the distribution of cell areas. This provides an image-based way to test for presence of mechanically induced extrusions and we identify this signature in the developing wing epithelium of \textit{D.~melanogaster}. We expect the same principles to apply to confined three-dimensional tissues.

physics.bio-ph↗