Drought effects on elongation kinetics and sugar deposition in the elongation zone of durum wheat (Triticum durum Desf.) leaves

Document Type : Original Article


1 Department of Biology, Faculty on Nature and Life Sciences, Ziane Achour University of Djelfa, Algeria

2 Laboratoire d’Ecophysiologie Végétale, Département de Biologie, Ecole Normale Supérieure de Kouba, Alger, Algérie



The aim of this study was to analyze the effect of drought stress on the kinetics of leaf elongation in relationship to the variation of sugar concentrations and their net deposition rates along the elongation zone of leaf 4 of durum wheat plants. Plants were grown in soil in a naturally illuminated greenhouse, and water was withheld from seedlings for a period of 14 days. Leaf 4 of 26 day-old plants was used for growth measurements and tissue sampling. Relative elemental growth rates (REGR), cell displacement velocity (DV), and elongation zone length (EZL) were significantly reduced by drought treatment. Together, this resulted in a decrease in leaf elongation rate (LER) in drought-stressed plants. Epidermal cell length along the elongation zone was not significantly affected by drought stress, indicating that the decrease in elongation zone length was due mainly to a reduction in cell production rate.  The concentration of total soluble sugars (TSS) and non-reducing sugars (NRS) was highest at the leaf base and decreased distally from 10 mm from the leaf base in plants grown under non-stressed (control) conditions. Drought stress caused a significant accumulation of TSS at the leaf base, mainly through an increase in non-reducing sugars. The continuity equation was used to calculate sugar net deposition rates. Drought stress increased the net deposition rates of non-reducing sugars in the first 10 mm from the leaf base. This increase was the principal source for the increase in non-reducing sugars concentrations at the leaf base in response to drought. 


Arif, H. and A.D. Tomos. 1993. ' Control of wheat leaf growth under saline conditions'. In:H Lieth, A Al Masoom, eds. Towards the Rational Use of High Salinity Tolerant Plant. Kluwer, Academic Publishers, Dordrecht, the Netherlands, pp: 45–52.
Beemster, G.T.S. and J. Masle. 1996. 'Effects of soil resistance to root penetration on leaf expansion in wheat (Triticum aestivumL.): composition, number and size of epidermal cells in mature blades’ Journal of Experimental Botany, 47: 1651-1662.
Bernstein, N., A. Läuchli and W.K. Silk. 1993a. 'Kinematics and dynamics of Sorghum (Sorghum bicolorL.) leaf development at various Na/Ca salinities (I. Elongation growth).' Plant Physiol, 103: 1107–1114.
Bernstein, N., A. Läuchli and W.K. Silk. 1993b. 'Growth and development of Sorghum leaves under conditions of NaCl stress'.Planta, 191: 433–439.
Bernstein, N., W.K. Silk and A. Läuchli. 1995. 'Growth and development of sorghum leaves under condition of NaCl stress: Possible role of some mineral elements in growth inhibition'.Planta, 196: 699–705.
Biswal, A.K and A. Kohli. 2013. 'Cereal flag leaf adaptations for grain yield under drought: Knowledge status and gaps'.Molecular Breeding, 31: 749–766.
Delane, R., H. Greenway, R. Munns and J. Gibbs. 1982. 'Ion concentration and carbohydrate status of the elongating leaf tissue of Hordeum vulgare growing at high external NaCl. I. Relationship between solute concentration and growth'.Journal of Experimental Botany, 33: 557–573.
Dubois, M., K.A. Gilles, J.K. Hamilton, P.A. Rebers and F. Smith. 1956. 'Colorimetric method for determination of sugars and related substances'. Analytical Chemistry, 28: 350356.
Durand, J., L. Onillon, B. Schnyder and H. Rademacher. 1995. 'Drought effects on cellular and spatial parameters of leaf growth in Tall fescue'. Journal of Experimental Botany, 46: 11471155.
Frensch, J. 1997. 'Primary responses of root and leaf elongation to water deficit in the atmosphere and soil solution'. Journal of Experimental Botany, 48: 985999.
Friedemann, T.E., C.W. Weber and N.F. Witt. 1962. 'Determination of reducing sugars by oxidation in alkaline ferricyanide solution'. Anal Biochem, 4:358–377.
Hilal, M., A.M. Zenoff, G. Ponessa, H. Moreno and E.M. Massa. 1998. 'Saline stress alters the temporal patterns of xylem differentiation and alternative oxidase expression in developing soybean roots'. Plant Physiol, 117: 695-701.
Hsiao, T.C., J. Frensch and B.A Rojas-Lara. 1998. 'The pressure- jump technique shows maize leaf growth to be enhanced by increases in turgor only when water status is not too high'. Plant, Cell and Environment, 21: 33-42.
Hsiao, T.C. and L.K. Xu. 2000. 'Sensitivity of growth of roots versus leaves to water stress: biophysical analysis and relation to water transport'. Journal of Experimental Botany, 51: 1595-1616.
Hu, Y. and U. Schmidhalter. 1998. 'Spatial distributions of inorganic ions and sugars contributing to osmotic adjustment in the elongation wheat leaf under saline soil conditions'. Australian Journal of Plant Physiology, 25: 591-597.
Hu, Y., K.H. Camp and U. Schmidhalter. 2000a. 'Kinetics and spatial distribution of leaf elongation of wheat (Triticum aestivum L.) under saline soil conditions'. International Journal of Plant Sciences, 161: 575-585.
Hu, Y., H. Schnyder and U. Schmidhalter. 2000b. 'Carbohydrate deposition and partitioning in elongating leaves of wheat under saline soil conditions'. Australian Journal of Plant Physiology, 27: 363-370.
Kameli, A. and D.M. Lösel. 1996. 'Growth and sugar accumulation in durum wheat plants under water stress'. New Phytologist, 132: 57-62.
Kemp, D.R. 1980. 'The location and size of the extension zone of emerging wheat leaves'. New Phytologist, 84: 729-737.
Lu, Z. and P.M. Neumann. 1999.  'Water stress inhibits hydraulic conductance and leaf growth in rice seedlings but not the transport of water via mercury-sensitive water channels in the root'. Plant Physiol, 120: 143-151.
Lüscher, M. and C.J. Nelson. 1995. 'Fructosyltransferase activities in the leaf growth zone of tall fescue'. Plant Physiology, 107: 1419-1425.
Munns, R. and R. Weir. 1981. 'Contribution of sugar to osmotic adjustment in elongating and expanded zones of wheat leaves during moderate water deficits at two light levels'. Australian Journal of Plant Physiology, 8: 93-105.
Neves-Piestun, B.G. and N. Bernstein. 2005. 'Salinity-induced changes in the nutritional status of expanding cells may impact leaf growth inhibition in maize'. Functional Plant Biology, 32: 141-152.
Nonami, H., Y. Wu and J.S. Boyer. 1997. 'Decreased growth-induced water potential (A primary cause of growth inhibition at low water potentials)'. Plant Physiology, 114: 501-509.
Ortega, L. and E. Taleisnik. 2003. 'Elongation growth in leaf blades of Chloris gayana under saline conditions'. Journal of Plant Physiology, 160: 517-522.
Ortega, L., S.C. Fry and E. Taleisnik. 2006. 'Why are Chloris gayana leaves shorter in salt-affected plants? Analyses in the elongation zone'. Journal of Experimental Botany, 57: 3945-3952.
Schnyder, H. and C.J. Nelson. 1987. 'Growth rates and carbohydrate fluxes within the elongation zone of tall fescue leaf blades'. Plant Physiol, 85: 548-553.
Schnyder, H. and C.J. Nelson. 1988. 'Diurnal growth of tall fescue leaf blades. I. Spatial distribution of growth, deposition of water, and assimilate import in the elongation zone'. Plant Physiol, 86: 1070-1076.
Schnyder, H. and C.J. Nelson. 1989. 'Growth rates and assimilate partitioning in the elongation zone of tall fescue leaf blades at high and low irradiance'. Plant Physiol, 90: 1201-1206.
Schnyder, H., C.J. Nelson and J. Coutts. 1987. 'Assessment of spatial distribution of growth in the elongation zone of grass leaf blades'. Plant Physiol, 85: 290-293
Schnyder, H., S. Seo, I.F. Rademacher and W. Kuhbauch. 1990. 'Spatial distribution of growth rates and of epidermal cell lengths in the elongation zone during leaf development in Lolium perenne L.' Planta, 181:423–431 .
Sharp, R.E., T.C. Hsiao and W.K. Silk. 1990. 'Growth of the primary roots at low water potentials. II. Role of growth and deposition of hexose and potassium in osmotic adjustment'. Plant Physiol, 93: 1337-1346.
Silk, W.K. 1984. 'Quantitative descriptions of development of expansive growth'. Annu Rev Plant Physiol, 35:479–518.
Silk, W.K. and K.K.Wagner. 1980. 'Growth sustaining water potential distribution in the primary corn roots'. Plant Physiol, 66: 859-863.
Silk, W.K. and M.B. Bojeat-Triboulot. 2014. 'Deposition rates in growing tissue: Implications for physiology, molecular biology, and response to environmental variation'. Plant Soil, 374, 1-17.
Spollen, W.G. and C.J. Nelson. 1994.  'Response of fructan to water deficit in growing leaves of tall fescue'. Plant Physiology, 106: 329-336.
Volenec, J.J. and C.J. Nelson. 1984. 'Carbohydrate metabolism in leaf meristems of tal1 fescue. I. Relationship to genetically altered leaf elongation rates'. Plant Physiol, 74: 590-594