Some species are resistant to high levels of aluminum in the soil. Tea (Camellia sinensis) has this ability in very acid soils where ion pairs "Al-P" are formed and absorbed by the roots.
Tea can accumulate aluminum by complexification with organic acids and flavonols and also benefit phosphorus absorbed with him. This phenomenon of absorbing "Al-P" pairs also explains the stimulatory effects on growth of low alumium levels for many crops.
Aluminium toxicity occurs mainly in highly acid soils i.e. andosols. Inhibition of root
elongation is the most evident manifestation of Al toxicity as well as P deficiencies due to phosphate retention in the mineral matrix. Plants may resist Al toxicity by Exclusion that involves the exudation of organic acid anions from the root and by Tolerance mechanisms though internal Al detoxification by organic acid anions and enhanced scavenging of free oxygen radicals.
I recommend a review paper that I came across recently:
Inostroza-Blancheteau et al. (2012) Molecular and physiological strategies to increase aluminum resistance in plants. Mol Biol Rep 39: 2069-2079
DOI: 10.1007/s11033-011-0954-4
Other intersesting references.
About stimulating effects at low Al soil levels:
- Bertand, R et H. Agulhon; 1912. C.R. VIIème Cong. Intern. Chim. Apll., New-York, 15, 37.
- Cerighelli, R.;1955. Cultures tropicales. I. Plantes vivrières, 6-171. Ed. Baillière et Fils, Paris.
- Hacket, C.; 1962. Stimulative effects of aluminium on plant growth. Nature, London, 195: 471-472.
- Mc Leod, L.B. and L.F. Jackson; 1965. Effect of concentration of the aluminium ion on root developpement and establishment of legume seedlings. Can. J. Soil Sci., 45 (2): 221-234.
Specially for tea and plant Al accumulators:
- Sivasubramaniam, S. and O. Talibudeen; 1971. Effect of aluminium on growth of tea (Camelia sinensis) and its uptake of potassium and phosphorus. J. Sci. Fd Agric., 22: 325-329.
- Chenery, E.M.;1955. A preliminary study of aluminium and the tea bush. Plant Soil 6: 174-200.
- Evrard, C., J. Roels, P. Remy, G. Tshitenge et H. Pollack; 1967. Détection par activation neutronique d'accumulateurs d'aluminium dans la flore congolaise. Atomic energy review 5 (3): 119-125.
More recent references:
- Clemens, S., M. G. Palmgren and U. Krämer; 2002. A long way ahead: understanding and engineering plant metal accumulation. TRENDS in Plant Science, Vol.7 No.7: 309-315
- Delhaize, E. and P. R. Ryan; 1995. Aluminum Toxicity and Tolerance in Plants. Plant Physiol. 107: 315-321
- Kochian,L.V., O. A. Hoekenga and M. A. Pineros;2004. How do crop plants tolerate acid soils? Mechanisms of Aluminium tolerance and Phosphorous efficiency. Annu. Rev. Plant Biol. 55: 459–493
- Kochian, L. V., A. M. Pineros & O. A. Hoekenga; 2005. The physiology, genetics and molecular biology of plant aluminum resistance and toxicity. Plant and Soil 274:175–195
- Ma, J.F., P. R. Ryan and E. Delhaize; 2001. Aluminium tolerance in plants and the complexing role of organic acids TRENDS in Plant Science Vol.6 No.6: 273-278
Besides the role of organic acid in alleviating aluminum toxicity in soil and plant, as also suggested by Dr. José González-Pérez, organic acids can also improve P availability by reducing its adsorption in soil. organic acids (in form of organic anions formed due to deprotonation of organic acids) compete with orthophosphate ions (H2PO4-, HPO42-) for the same adsorption sites reducing thereby the adsorption of P. (ligand exchange mechanism)
Interesting discussion . One of the most conspicuous effects of Al-toxicity is the suberisation of root hairs , thereby , impairing with nutrients translocation . The tolerant cultivars efficiently took up and utilized Ca and P in the presence of aluminium. The susceptible (Al-sensitive) and intermediate cultivars exhibited less Ca and P uptake and utilization. An interesting PDF is enclosed for further reading , please..
- Badges
- Science topic
- Similar topics
- Agricultural Science
- Agronomy