What are the implications of variation in root hair length on tolerance to phosphorus deficiency in combination with water stress in barley (Hordeum vulgare)?
Open Access
- 25 April 2012
- journal article
- research article
- Published by Oxford University Press (OUP) in Annals of Botany
- Vol. 110 (2), 319-328
- https://doi.org/10.1093/aob/mcs085
Abstract
Phosphorus commonly limits crop yield and is frequently applied as fertilizer; however, supplies of quality rock phosphate for fertilizer production are diminishing. Plants have evolved many mechanisms to increase their P-fertilizer use efficiency, and an understanding of these traits could result in improved long-term sustainability of agriculture. Here a mutant population is utilized to assess the impact of root hair length on P acquisition and yield under P-deficient conditions alone or when combined with drought. Mutants with various root hair phenotypes were grown in the glasshouse in pots filled with soil representing sufficient and deficient P treatments and, in one experiment, a range of water availability was also imposed. Plants were variously harvested at 7 d, 8 weeks and 14 weeks, and variables including root hair length, rhizosheath weight, biomass, P accumulation and yield were measured. The results confirmed the robustness of the root hair phenotypes in soils and their relationship to rhizosheath production. The data demonstrated that root hair length is important for shoot P accumulation and biomass, while only the presence of root hairs is critical for yield. Root hair presence was also critical for tolerance to extreme combined P deficit and drought stress, with genotypes with no root hairs suffering extreme growth retardation in comparison with those with root hairs. The results suggest that although root hair length is not important for maintaining yield, the presence of root hairs is implicit to sustainable yield of barley under P-deficient conditions and when combined with extreme drought. Root hairs are a trait that should be maintained in future germplasm.Keywords
This publication has 33 references indexed in Scilit:
- A structured mutant population for forward and reverse genetics in Barley (Hordeum vulgare L.)The Plant Journal, 2004
- Barley genotypes with long root hairs sustain high grain yields in low-P fieldPlant and Soil, 2004
- The role of ethylene in root hair growth inArabidopsisJournal of Plant Nutrition and Soil Science, 2001
- Mineral acquisition by arbuscular mycorrhizal plantsJournal of Plant Nutrition, 2000
- The efficiency of Arabidopsis thaliana (Brassicaceae) root hairs in phosphorus acquisitionAmerican Journal of Botany, 2000
- Direct evidence on participation of root hairs in phosphorus (32P) uptake from soilPlant and Soil, 1998
- Stimulation of root hair elongation in Arabidopsis thaliana by low phosphorus availabilityPlant, Cell & Environment, 1996
- Mycorrhizal responses of barley cultivars differing in P efficiencyPlant and Soil, 1993
- Water uptake and storage by rhizosheaths of Oryzopsis hymenoides: a numerical simulationPhysiologia Plantarum, 1985
- The influence of root hairs on the uptake of phosphateCommunications in Soil Science and Plant Analysis, 1970