The Phi Thickening in Roots of Broccoli Plants: An Acclimation Mechanism to Salinity?
- 1 October 2007
- journal article
- Published by University of Chicago Press in International Journal of Plant Sciences
- Vol. 168 (8), 1141-1149
- https://doi.org/10.1086/520722
Abstract
Although broccoli is moderately tolerant to salt stress, the tolerance mechanism is still unknown. Therefore, in this article, the uptake and transport of nutrients and water in relation to the changes in root anatomy (phi thickening appearance) caused by salinity stress have been studied. The effect of phi thickening in the response of these plants to salinity was studied by comparing two methods of measuring root hydraulic conductance, pressurizing roots and natural exudation, and analyzing the nutrient concentrations in the xylem. The permeability properties of phi thickening were tested by a tracer that moves only via the apoplastic pathway. Brassica oleracea L. var. Italica plants, grown under different levels of NaCl (0, 40, and 80 mM), showed modifications in the cell wall of the cortical layer bordering the endodermis, such as phi thickenings. The results also showed a decrease of the L0 and GS of plants under salinity stress and an ionic imbalance in the xylem sap. Na+, Mg2+, , and Cl− concentrations increased, while Ca2+ decreased. The fact that the proportion of apoplastic movement, which was higher when plants were measured with the Scholander chamber than with natural exudation, was lower for NaCl‐treated plants whereas the alteration of nutrient uptake was similar suggests that the phi thickenings could be a physical barrier only to apoplastic water transport.This work was funded by the Centro de Investigación Científica y Tecnológica (AGL2005‐00650/AGR).Peer revieweKeywords
This publication has 54 references indexed in Scilit:
- Interactive effects of salinity and water stress on growth, leaf water relations, and gas exchange in amaranth(Amaranthusspp.)New Zealand Journal of Crop and Horticultural Science, 2006
- Methods and concepts in quantifying resistance to drought, salt and freezing, abiotic stresses that affect plant water statusThe Plant Journal, 2006
- Osmotic adjustment, water relations and gas exchange in pepper plants grown under NaCl or KClEnvironmental and Experimental Botany, 2004
- Does calcium determine water uptake under saline conditions in pepper plants, or is it water flux which determines calcium uptake?Plant Science, 2004
- Physiological function of water channels as affected by salinity in roots of paprika pepperPhysiologia Plantarum, 1999
- Mineral nutrient transport by sunflower seedlings grown under saline conditions (NaCl)Journal of Plant Nutrition, 1996
- Developmental Changes of Cotton Root Primary Tissues Induced by SalinityInternational Journal of Plant Sciences, 1995
- Effect of salinity on growth, ion content and CO2 assimilation rate in lemon varieties on different rootstocksPhysiologia Plantarum, 1993
- Hydraulic Resistance of Plants. III. Effects of NaCl in Barley and LupinFunctional Plant Biology, 1984
- The development of the endoder mis andPhi layer of apple rootsProtoplasma, 1979