Root response of woody phreatophyte species to drought stress (Case study: Eucalyptus camaldulensis Dehnh)

Document Type : Scientific Letters

Authors

1 Assistant Prof., Research Division of Natural Resources, Yazd Agricultural and Natural Resource Research and Education Center, AREEO, Yazd, Iran

2 Research Expert, Research Division of Natural Resources, Yazd Agricultural and Natural Resource Research and Education Center, AREEO, Yazd, Iran

Abstract

Phreatophytes are the plants that supply their water requirements directly through the development of efficient roots from surface water resources and for optimum growth, the root should be in direct contact with water or a completely moist soil. Considering the importance of roots in the process of water and nutrient uptake from soil, it is necessary to study the mechanism of root adaptation to environmental stresses, including drought stress, especially in woody phreatophyte species, which are more important in forestation. In this research, the weight and length distribution of Eucalyptus camaldulensis Dehnh roots as a pharotypophyte species was investigated. The experiment was carried out under lysimetric conditions at different irrigation regimes (irrigation at field capacity as control, 30% and 60% of deficit irrigation). The results of this study indicated that the weight and root length decreased with decreasing plant access to water or deficit irrigation. The weight and length distribution of roots at different depths depended on the amount of plant access to water, so that the root distribution in the deeper soil decreased by increased deficit irrigation stress. Therefore, it can be concluded that, in contrast to xerophyte and mesophyte plants, the root penetration of E. camaldulensis depends thoroughly on the amount of water in the deeper soil depths. In other words, the dried underlying layers of soil inhibit the root growth in the depths, and the plant manages its vegetative growth through adaptation with available water in the soil surface layers.

Keywords


- Banon, S., Fernandez, J. A., Franco, J.A., Torrecillas, A., Alarcon, J.J. and Sanchez –Blanco , M.J., 2004. Effects of water stress and night temperature preconditioning on water relation and morphological and anatomical changes of Lotus creticus plants. Scientia Horticultural, 101: 331-342.
- Bacelar, E.A., Moutinho, J.M., Goncalves, B.c., Ferreira, H.F. and Correia, C.M. 2007. Changes in growth, gas exchange, xylem hydraulic properties and water use effiency of tree olive cultivars under contrasting water availability regimes. Environmental and Experimental Botany, 60: 183-192.
 - Bargali, K. and Tewari. A., 2004. Growth and water relation parameters in drought-stressed Coriaria nepalensis seedling. Journal Of Arid Environment, 58: 505-512.
 - Batelaan, O., De Smedt, F. and Triest, L., 2003. Regional groundwater discharge: phreatophyte mapping, groundwater modelling and impact analysis of land-use change. Journal of Hydrology, 275(1-2): 86-108.
 - Carbon, B.A., Bartle, G.A., Murray, A.M. and Macpherson, D.k., 1980. The distribution of root length, and the limits to flow of soil water to roots in a dry scleophyll forest. Forest. Science, 26: 656-664.
 - Dias, P.C., Araujo,W.l., Moraes, G.a.b.k., Barros, R.S. and Damatta, F.M., 2007. Morphological and physiological responses of two coffee progenies to soil water availability. Journal of Plant Physiology, 164: 1639-1647.
 - Drunasky, N. and Struve, D.K., 2005. Quercus macrocarpa and Q. prinus physiological and morphological responses to drought stress and their potential for urban forestry. Urban Forestry & Urban Greening, 4: 13-22.
- Gazal, R.M. and Kubiske, M.E., 2004. Influence of initial root length on physiological responses of cherry bark oak and shumard oak seedling to field drought conditions. Forest Ecology and Management, 189: 295-305.
 - Jena, S.K., Sahoo, N., Roy Chowdhury, S., Mohanty, R.K., Kundu, D.K., Behera, M.S., Patil, D.U. and Kumar, A., 2011. Reclamation of coastal waterlogged wasteland through bio drainage. Journal Indian Society Coastal Agriculture Research, 29: 57-62.
 - Jobbágy, E.G. and Jackson, R.B., 2007. Groundwater and soil chemical changes under phreatophytic tree plantations. Journal of Geophysical Research: Biogeosciences, 112: 1-15.
- Kramer, P.J. and Boyer, J.S., 1995. Water relation of plants and soil. San Diego: Academic Press. 495p.
 - Landmeyer, J.E., 2012. Monitoring Plant and Groundwater Interactions. In Introduction to Phytoremediation of Contaminated Groundwater (pp. 209-232). Springer, Dordrecht. https://link.springer.com/chapter/10.1007/978-94-007-1957-6-9.
-  Li, C. and Wang, K., 2003. Differences in drought responses of three contrasting Eucalyptus microtheca F. Muell populations. Forest Eology and Management, 179: 377-385.
- Maricle, B.R., Cobos, D.R. and Campbell, C.S., 2007. Biophysical and morphological leaf adaptations to drought and salinity in salt marsh grasses. Environmental and Experimental Botany, 60: 458–467.
 - Nichols, W.D., 1994. Groundwater discharge by phreatophyte shrubs in the Great Basin as related to depth to groundwater. Water Resource. Research, 30: 3265–3274.
 - Susiluoto, S. and Berninger, F., 2007. Interactions between Morphological and Physiological Drought Responses in Eucalyptus microtheca. Silva Fennica, 41: 221-233.
 - Thomas, F.M. and Gausling, T., 2000. Morphological and physiological responses of oak seedlings (Quercus petraea and Q. robur) to moderate drought. Annals of Forest Science, 57(4), pp.325-333.
- White, D.A., Turner, N.C. and Galbraith, J.H., 2000. Leaf water relations and stomatal behavior of four allopatric Eucalyptus species planted in Mediterranean southwestern Australia. Tree Physiol, 20: 1157–1165.
 - Whitehead, d. and Beadle, C.L., 2004. Physiological regulation of productivity and water use in Eucalyptus: a review.  Forest Ecology and Management, 193: 113-140.
- Yin, C., Wang, X., Duan, B., Luo, J. and li, C., 2005. Early growth, dry matter allocation and water use efficiency of two sympatric Populus species as affected by water stress. Forest Ecology and Management, 193: 113-140.