Macronutrient chloride nutrition improves root architecture through stimulation of cell division and elongation

Macronutrient chloride nutrition improves root architecture through stimulation of cell division and elongation Chloride (Clˉ) is known to be an essential micronutrient for higher plants due to its participation in key physiological processes such as photosynthesis and osmotic regulation. Recently, we have proved that Clˉ accumulation at macronutrient levels (20-50 mg gˉ¹ DW) is benefcial for plant development, resulting in morphological and cellular changes in aboveground organs that stimulates leaf cell size and induces physiological and metabolic alteration that result in a higher efciency in the plant use of water, nitrogen, and CO₂/energy (Colmenero-Flores et al, 2019). Belowground, the plant root system has an essential function in water and nutrient uptake and further distribution to shoot organs via the vascular system. Optimal access to water and nutrients requires adequate root architecture, which is modeled based on environmental stimuli (e.g., the presence of soil nitrate patches) and is regulated by hormonal factors, among which auxin is particularly relevant. At the cellular level auxin specifcally induces the uptake of Clˉ and potassium to stimulate cell elongation. Although some Clˉ transporters such Clˉ Channels (ClCs) and CationClˉ cotransporters (CCCs) participate in root cell elongation and growth, the role of Cl− nutrition in regulating root architecture is unknown. This work aims to study the role of Clˉ nutrition on root tip architecture and development using Arabidopsis wild type and mutant lines afected in cell cycle and root auxin transport (Álvarez-Buvlla et al, 2019; Garay-Arroyo et al, 2013). References Alvarez‐Buylla et al. (2019) New Phytologist, 223(3), 1143-1158. Colmenero-Flores et al. (2019) Int. J. Mol. Sci. 20:4686. Garay‐Arroyo et al. (2013) The EMBO journal, 32(21), 2884-2895.