Cell membrane integrity, callose accumulation, and root growth in aluminum-stressed sorghum seedlings
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Aluminum stress usually reduces plant root growth due to the accumulation of Al in specific zones of the root apex. The objectives of this study were to determine the localization of Al in the root apex of Sorghum bicolor (L.) Moech. and its effects on membrane integrity, callose accumulation, and root growth in selected cultivars. Seedlings were grown in a nutrient solution containing 0, 27, or 39 μM Al3+ for 24, 48, and 120 h. The Al stress significantly reduced root growth, especially after 48 and 120 h of exposure. A higher Al accumulation, determined by fluorescence microscopy after staining with a Morin dye, occurred in the root extension zone of the sensitive cultivar than in the tolerant cultivar. The membrane damage and callose accumulation were also higher in the sensitive than resistant cultivar. It was concluded that the Al stress significantly reduced root growth through the accumulation of Al in the root extension zone, callose accumulation, and impairment of plasma membrane integrity.
Additional key wordsaluminum tolerance root extension zone
Eastern African Regional Programme and Research Network for Biotechnology, Biosafety and Biotechnology Policy Development
International Crops Research Institute for the Semi-Arid Tropics
Swedish International Development Agency
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- Illéš, P., Schlicht, M., Pavlovkin, J., Lichtscheidl, I., Baluška, F., Ovečka, M.: Aluminium toxicity in plants: internalization of aluminium into cells of the transition zone in Arabidopsis root apices related to changes in plasma membrane potential, endosomal behaviour, and nitric oxide production. — J. exp. Bot. 57: 4201–4213, 2006.PubMedCrossRefGoogle Scholar
- Magalhaes, J.V., Liu, J., Guimaraes, C.T., Lana, U.G., Alves, V.M., Wang, Y.H., Schaffert, R.E., Hoekenga, O.A., Pineros, M.A., Shaff, J.E., Klein, P.E., Carneiro, N.P., Coelho, C.M., Trick, H.N., Kochian, L.V.: A gene in the multidrug and toxic compound extrusion (MATE) family confers aluminum tolerance in sorghum. — Nat. Genet. 39: 1156–1161, 2007.PubMedCrossRefGoogle Scholar
- Ringo, J.H., Mneney, E.E., Onkware, A.O., Were, B.A., Too, E.J., Owuoche, J.O., Gudu, S.O.: Tolerance to aluminium toxicity in Tanzanian sorghum genotypes. — Afr. Crop Sci. J. 18: 155–164, 2010.Google Scholar
- Sivaguru, M., Fujiwara, T., Samaj J., Baluska, F., Yang, Z., Osawa, H., Maeda, T., Mori, T., Volkmann, D., Matsumoto, H.: Aluminium-induced 1-3-β-glucan inhibits cell-to-cell trafficking of molecules through plasmodesmata. A new mechanism of aluminium toxicity in plants. — Plant Physiol. 124: 991–1005, 2000.PubMedCrossRefPubMedCentralGoogle Scholar
- Too, E.J.: Physiological and Molecular Characterization of Resistance to Aluminium Stress in Selected Grain Sorghums. — Thesis. Biological Sciences, Moi University, Eldoret 2011.Google Scholar