Affordable Access

High-affinity K+ uptake in pepper plants.

Authors
  • Martínez-Cordero, M Angeles1
  • Martínez, Vicente
  • Rubio, Francisco
  • 1 Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-CSIC, Apartado de Correos 164, E-30100 Murcia, Spain.
Type
Published Article
Journal
Journal of experimental botany
Publication Date
June 2005
Volume
56
Issue
416
Pages
1553–1562
Identifiers
PMID: 15809279
Source
Medline
License
Unknown

Abstract

High-affinity K+ uptake is an essential process for plant nutrition under K+-limiting conditions. The results presented here demonstrate that pepper (Capsicum annuum) plants grown in the absence of NH4+ and starved of K+ show an NH4+-sensitive high-affinity K+ uptake that allows plant roots to deplete external K+ to values below 1 microM. When plants are grown in the presence of NH4+, high-affinity K+ uptake is not inhibited by NH4+. Although NH4+-grown plants deplete external K+ below 1 microM in the absence of NH4+, when 1 mM NH4+ is present they do not deplete external K+ below 10 microM. A K+ transporter of the HAK family, CaHAK1, is very likely mediating the NH4+-sensitive component of the high-affinity K+ uptake in pepper roots. CaHAK1 is strongly induced in the roots that show the NH4+-sensitive high-affinity K+ uptake and its induction is reduced in K+-starved plants grown in the presence of NH4+. The NH4+-insensitive K+ uptake may be mediated by an AKT1-like K+ channel.

Report this publication

Statistics

Seen <100 times