Spatial heterogeneity of flesh-cell osmotic potential in sweet cherry affects partitioning of absorbed water

Abstract

A fleshy fruit is commonly assumed to resemble a thin-walled pressure vessel containing a homogenous carbohydrate solution. Using sweet cherry (Prunus avium L.) as a model system, we investigate how local differences in cell water potential affect H 2 O and D 2 O (heavy water) partitioning. The partitioning of H 2 O and D 2 O was mapped nondestructively using magnetic resonance imaging (MRI). The change in size of mesocarp cells due to water movement was monitored by optical coherence tomography (OCT, non-destructive). Osmotic potential was mapped using microosmometry (destructive). Virtual sections through the fruit revealed that the H 2 O distribution followed a net pattern in the outer mesocarp and a radial pattern in the inner mesocarp. These patterns align with the disposition of the vascular bundles. D 2 O uptake through the skin paralleled the acropetal gradient in cell osmotic potential gradient (from less negative to more negative). Cells in the vicinity of a vascular bundle were of more negative osmotic potential than cells more distant from a vascular bundle. OCT revealed net H 2 O uptake was the result of some cells loosing volume and other cells increasing volume. H 2 O and D 2 O partitioning following uptake is non-uniform and related to the spatial heterogeneity in the osmotic potential of mesocarp cells.

Phytotoxic effects of treated wastewater used for agricultural irrigation on root hydraulic conductivity and plant growth

“…In roots, hydraulic conductance influences water uptake capacity, which depends on the plant's root surface area, root anatomy, and root water permeability (Niu et al, 2020, Meunier et al, 2018, canals et al, 2021. The dominating driving force for water uptake is the water potential gradient, which depends on osmotic gradients (Grimm et al, 2020, Bazihizina et al, 2017, Deluliis et al, 2021.…”

Phytotoxic Effects of Treated Wastewater Used for Agricultural Irrigation On Root Hydraulic Conductivity and Plant Growth

“…In roots, hydraulic conductance in uences water uptake capacity, which depends on the plant's root surface area, root anatomy, and root water permeability (Niu et al, 2020, Meunier et al, 2018, canals et al, 2021. The dominating driving force for water uptake is the water potential gradient, which depends on osmotic gradients (Grimm et al, 2020, Bazihizina et al, 2017, Deluliis et al, 2021.…”

Decreased deposition and increased swelling of cell walls contribute to increased cracking susceptibility of developing sweet cherry fruit

“…The giant flesh cells have more negative osmotic potentials and thinner cell walls than the much-smaller, thicker-walled cells of the skin’s epidermis and hypodermis (Grimm and Knoche 2015 ). Not all cells of the flesh are of the same osmotic potential (Grimm et al 2020 ). Hence, those having the most negative osmotic potentials will likely burst first (Grimm et al 2019 ).…”