Phosphorous uptake and utilization efficiency in cluster root and non-cluster root forming species of the Core Cape Subregion, South Africa

• Main Author: Basic, Dunja
• Other Authors: Chimphango, Samson
• Format: Dissertation
• Language: English
• Published: University of Cape Town 2015
• Subjects: Biological Sciences
• Online Access: http://hdl.handle.net/11427/15470

The Core Cape Subregion (CCR) is made up of a mosaic of highly weathered and nutrient leached soil substrates in the Western Cape. Plant available phosphorus (P) in these soils is very low, generally ranging from 0.4-3.7 µg P g-1 soil and as a result plants have evolved a number of traits to enhance P-acquisition, such as increased root surface area (SA) and specific root length (SRL), cluster root and root hair proliferation and exudation of organic acids and acid phosphatases (APase) from the roots. Crop yield is limited worldwide due to the unavailability of P and P-fertilization is showing limited success due to soil retention. Sustainable management of this would include exploiting plants with natural adaptations for enhanced P acquisition and utilization. The aim of this study was to discover whether cluster root forming species are more efficient at P acquisition than non-cluster root species. This was achieved by focusing on two objectives: (1) to characterize root traits for increased P acquisition in different soils of the CCR and (2) comparing P-uptake and utilization efficiencies of cluster root species to non-cluster root species under glasshouse and natural conditions. Plants from Fabaceae, Polygalaceae, Proteaceae, Cyperaceae, and Juncaceae were grown in two different glasshouse experiments and observed in a field study.