Proteoid roots

J. F. Johnson, D. L. Allan, C. P. Vance, and G. Weiblen, Root carbon dioxide fixation by phosphorus deficient Litpinus aihus. Contribution to organic acid exudation by proteoid roots. Plant Physiol. II2 9 (1996). 

G. Neumann, A. Massonneau, E. Martinoia, and V. Romheld, Physiological adaptations to phosphorus deficiency during proteoid root development in white lupin. Planta 208 313 (1999). 

J. Gerke, W. Romer, and A. Jungk, The excretion of citric and malic acid by proteoid roots of Liipinus aihus L. effects on soil solution concentrations of phosphate, iron, and aluminium in the proteoid rhizosphere samples of an Oxisol and a Luvi.sol. Z. Pktnzenernaehr. Bodenk. I57 2S9 (1994). 

M. Arahou and H. G. Diem, Iron deficiency induces cluster (proteoid) root formation in Casuarina i>lauca. Plant Soil I96 7 (1997). 

G. Keerthisinghe, P. J. Hooking, P. R. Ryan, and E. Delhaize, Effect of phosphorus supply on the formation and function of proteoid roots of white lupin (Lupinus albiis L.). Plant Cell Environm. 21 467 (1998). 

M. Watt and J. Evans, Linking development and determinacy with organic acid efflux from proteoid roots of white lupin grown with low phosphorus and ambient or elevated atmospheric COi concentration. Plant Pltywlol. 120 705 (1999). 

Other sand-based systems using COi pulse-chase procedures have been used to produce carbon budgets for Festuca ovina and Plantago lanceolata seedlings (30) and white lupin (Lupimis albiis) (31). Significantly, CO2 pulse labeling of proteoid roots of white lupin under phosphate-deficient conditions showed that high levels of dark fixation of COi by the roots took place and that 66% of this root-fixed carbon was exuded from the roots (31). Clearly, dark fixation of CO2 by roots and subsequent rhizodeposition is an area that deserves further study in the future. 

Wenzel, C. L., Ashford, A. E. Summerell, B. A. (1994). Phosphate-solubilizing bacteria associated with proteoid roots of seedlings of warratah [Telopea speciosissima (Sm.) R. Br.]. New Phytologist, 128, 487-96. 

Dinkelaker, B., Hengeler, C., and Marschner, H. (1995). Distribution and function of proteoid roots and other root clusters. Bot. Acta 108, 183-200. 

Miller, S.S., Liu, J.Q., Allan, D.L., Menzhuber, C.J., Fedorova, M. and Vance, C.P. (2001) Molecular control of acid phosphatase secretion into the rhizosphere of proteoid roots from phosphorus-stressed white lupin. Plant Physiology 127, 594-606. 

Pate, J.S. and Watt, M. (2002) Roots of Banksia spp. (Proteaceae) with special reference to functioning of their specialized proteoid root clusters. In Waisel, Y., Eshel, A. and Kafkafi, LJ. (eds) Plant Roots the Hidden Half. Marcel Dekker, New York, pp. 989-1005. 

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