Influence of Leaf Tolerance Mechanisms and Rain on Boron Toxicity in Barley and Wheat
- 22 July 2009
- journal article
- Published by Oxford University Press (OUP) in Plant Physiology
- Vol. 151 (1), 413-420
- https://doi.org/10.1104/pp.109.141069
Abstract
Boron (B) toxicity is common in many areas of the world. Plant tolerance to high B varies widely and has previously been attributed to reduced uptake of B, most commonly as a result of B efflux from roots. In this study, it is shown that the expression of genes encoding B efflux transporters in leaves of wheat (Triticum aestivum) and barley (Hordeum vulgare) is associated with an ability of leaf tissues to withstand higher concentrations of B. In tolerant cultivars, necrosis in leaves occurred at B concentrations more than 2-fold higher than in sensitive cultivars. It is hypothesized that this leaf tolerance is achieved via redistribution of B by efflux transporters from sensitive symplastic compartments into the leaf apoplast. Measurements of B concentrations in leaf protoplasts, and of B released following infiltration of leaves, support this hypothesis. It was also shown that under B-toxic conditions, leaching of B from leaves by rain had a strong positive effect on growth of both roots and shoots. Measurements of rates of guttation and the concentration of B in guttation droplets indicated that the impact of guttation on the alleviation of B toxicity would be small.Keywords
This publication has 15 references indexed in Scilit:
- Plants Tolerant of High Boron LevelsScience, 2007
- Cell-Type Specificity of the Expression of Os BOR1, a Rice Efflux Boron Transporter Gene, Is Regulated in Response to Boron Availability for Efficient Boron Uptake and Xylem LoadingPlant Cell, 2007
- Boron Tolerance in Barley Is Mediated by Efflux of Boron from the RootsPlant Physiology, 2004
- Is the infiltration‐centrifugation technique appropriate for the isolation of apoplastic fluid? A critical evaluation with different plant speciesPhysiologia Plantarum, 2001
- Mapping of chromosome regions conferring boron toxicity tolerance in barley (Hordeum vulgare L.)Theoretical and Applied Genetics, 1999
- Boron toxicityPlant and Soil, 1997
- Boron in plant cell wallsPlant and Soil, 1997
- Problems associated with the use of foliar analysis for diagnosing boron toxicity in barleyPlant and Soil, 1990
- Boron determination in plant tissue by the azomethine H methodCommunications in Soil Science and Plant Analysis, 1979
- LOSS OF BORON FROM PLANTS THROUGH GUTTATIONSoil Science, 1962