Table of Contents
Journal of Botany
Volume 2012, Article ID 580342, 11 pages
http://dx.doi.org/10.1155/2012/580342
Research Article

Role of Ascorbate in the Regulation of the Arabidopsis thaliana Root Growth by Phosphate Availability

Chair of Plant Physiology and Biotechnology, Nicolaus Copernicus University, Gagarina 9, 87-100 Toruń, Poland

Received 24 July 2011; Accepted 4 October 2011

Academic Editor: Philip White

Copyright © 2012 Jarosław Tyburski et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Arabidopsis root system responds to phosphorus (P) deficiency by decreasing primary root elongation and developing abundant lateral roots. Feeding plants with ascorbic acid (ASC) stimulated primary root elongation in seedlings grown under limiting P concentration. However, at high P, ASC inhibited root growth. Seedlings of ascorbate-deficient mutant (vtc1) formed short roots irrespective of P availability. P-starved plants accumulated less ascorbate in primary root tips than those grown under high P. ASC-treatment stimulated cell divisions in root tips of seedlings grown at low P. At high P concentrations ASC decreased the number of mitotic cells in the root tips. The lateral root density in seedlings grown under P deficiency was decreased by ASC treatments. At high P, this parameter was not affected by ASC-supplementation. vtc1 mutant exhibited increased lateral root formation on either, P-deficient or P-sufficient medium. Irrespective of P availability, high ASC concentrations reduced density and growth of root hairs. These results suggest that ascorbate may participate in the regulation of primary root elongation at different phosphate availability via its effect on mitotic activity in the root tips.