Home > Research > Publications & Outputs > Regulation of K+ channels in maize roots by wat...


Text available via DOI:

View graph of relations

Regulation of K+ channels in maize roots by water stress and abscisic acid

Research output: Contribution to Journal/MagazineJournal articlepeer-review

<mark>Journal publication date</mark>01/1998
<mark>Journal</mark>Plant Physiology
Issue number1
Number of pages9
Pages (from-to)145-153
Publication StatusPublished
<mark>Original language</mark>English


Root cortical and stelar protoplasts were isolated from maize (Zea mays L.) plants that were either well watered or water stressed, and the patch-clamp technique was used to investigate their plasma membrane K+ channel activity. In the root cortex water stress did not significantly affect inward-or outward-rectifying K+ conductances relative to those observed in well-watered plants. In contrast, water stress significantly reduced the magnitude of the outward-rectifying K+ current in the root stele but had little effect on the inward-rectifying K+ current. Pretreating well-watered plants with abscisic acid also significantly affected K+ currents in a way that was consistent with abscisic acid mediating, at least in part, the response of roots to water stress. It is proposed that the K+ channels underlying the K+ currents in the root stelar cells represent pathways that allow K+ exchange between the root symplasm and xylem apoplast. It is suggested that the regulation of K+ channel activity in the root in response to water stress could be part of an important adaptation of the plant to survive drying soils.