[1] Abd El-Rahim, H.A. (2006) Characterisiation and possible agricultural application of polyacrylamide/sodium alginate crosslinked hydrogels prepared by ionizing radiation. Journal of Applied Polymer Science, 101, 3572-3580. doi:10.1002/app.22487
[2] Huttermann, A., Orikiriza, L.J.B. and Agaba, H. (2009) Application of superabsorbent polymers for improving the ecological chemistry of degraded or polluted lands. Clean—Soil, Air, Water, 37, 517-526. doi:10.1002/clen.200900048
[3] Dorajji, S.S., Golchin A. and Ahmadi, S. (2010) The effects of hydrophilic polymer and soil salinity on corn growth in sandy and loamy soils. Clean—Soil, Air, Water, 38, 584-591.
[4] Kramer, P.J. and Boyer, J.S. (1995) Water relations of plants and soils. Academic Press, London.
[5] Bhardwaj, A.K., Shainberg, I., Goldstein, D., Warrington, D.N. and Levy, G.J. (2007) Water retention and hydraulic conductivity of cross-linked polyacrylamides in sandy soils. Soil Science Society of America, 71, 406-412. doi:10.2136/sssaj2006.0138
[6] Huttermann A., Zommorodi, M. and Reise, K. (1999) Addition of hydrogels to soil for prolonging the survival of pinus halepensis seedlings subjected to drought. Soil & Tillage Research, 50, 295-304. doi:10.1016/S0167-1987(99)00023-9
[7] Helalia, A.M. and Letey, J. (1989) Effects of different polymers on seedling emergence, aggregate stability and crust hardness. Soil Science, 148, 199-203. doi:10.1097/00010694-198909000-00007
[8] Teyel, M.Y. and El-Hady, O.A. (1981) Super gel as a soil conditioner. Acta Horticulture, 119, 247-256.
[9] Jobin P., Caron J., Bernier, P.Y. and Dansereau B. (2004) Impact of twohydrophilic acrylic-based polymers on the physical properties of three substrates and the growth of Petunia hybrida “Brilliant Pink”. Journal of the American Society for Horticultural Science, 129, 449-457.
[10] Agaba, H., Orikiriza, L.J.B., Esegu, J.F.O., Obua, J., Kabasa, J.D, and Huttermann, A. (2010) Effects of hydrogel amendment to different soils on plant available water and survival of trees under drought conditions. Clean—Soil, Air, Water, 38, 328-335. doi:10.1002/clen.200900245
[11] Fiscus, E.L., Wullschleger, S.D. and Duke, H.R. (1984) Integrated Stomatal opening as indicator of water stress in zea mays. Crop Science, 24, 245-249. doi:10.2135/cropsci1984.0011183X002400020009x
[12] Fiscus, E.L., Mahbub-Ul Alam, A.N.M. and Hirasawa, T. (1991) Fractional integrated stomatal opening to control water stress in the field. Crop Science, 31, 1001-1008. doi:10.2135/cropsci1991.0011183X003100040032x
[13] Taylor, K.C. and Halfacre, R.G. (1986) The effect of hydrophilic polymer on media water retention and nutrient availability to Ligustrum lucidum. Horticultural Science, 21, 1159-1161.
[14] Bai, W., Zhang, H., Liu, B., Wu, Y. and Song, J. (2010) Effects of super-absorbent polymers on the physical and chemical properties of soil following different wetting and drying cycles. Soil Use and Management, 26, 253- 260. doi:10.1111/j.1475-2743.2010.00271.x
[15] Wallace, J.S. (1991) The measurement and modelling of evaporation from semiarid land. In: Sivakumar, M.V.K., Wallace, J.S., Renard, C. and Giroux, C., Eds., Soil water balance in the Sudano-Sahelian Zone. Proceedings of Niamey Workshop, IAHS Publication No. 199, 131-148
[16] Wallace, J.S. (1996) The water balance of mixed tree-crop systems. In: Ong, C.K. and Huxley, P., Eds., Tree-Crop Interactions: A Physiological Approach, CAB International, Wallingford.
[17] Huttermann, A., Reise, K., Zommorodi, M. and Wang, S. (1997) The use of hydogels for afforestation of difficult stands: Water and salt stress, in semi-arid regions In: H. Zhou and H. Weisgerber, Eds., Afforestation in Semi-Arid Regions, Datong.
[18] Graciano, C., Guiamet, J.J. and Goya, J.F. (2005) Impact of nitrogen and phosphorus fertilization on drought responses in Eucalyptus grandis seedlings. Forest Ecology and Management, 212, 40-49. doi:10.1016/j.foreco.2005.02.057
[19] Woodhouse, J. and Johnson, M.S. (1991) Effect of superabsorbent polymers on survival and growth of crop seedlings. Agricultural Water Management, 20, 63-70. doi:10.1016/0378-3774(91)90035-H
[20] Ciais, P.H., Reichstein, M., Viovy, N., Granier, A., Allard, V., et al. (2005) Europe-wide reduction in primary productivity caused by the heat and drought in 2003. Nature, 437, 529-533. doi:10.1038/nature03972
[21] Gomez-Cadenas, A., Tadeo, F.R., Talon, M. and Primo-Millo, E. (1996) Leaf abscission induced by ethylene in water stressed intact seedling of Citrus reshni Hort exTan requires previous abscisic acid accumulation in roots. Plant Physiology, 112, 401-408.
[22] Sinclair, T.R. and Allen, L.H.Jr. (1982) Carbon dioxide and water vapour exchange of leaves on field-grown citrus trees. Journal of Experimental Botany, 33, 1166- 1175. doi:10.1093/jxb/33.6.1166
[23] Syvertsen, J.P., Lloyd, J. and Kriedemann, P.E. (1988) Salinity and drought stress effects on ion concentration, water relations and photosynthetic characteristics of orchard citrus. Australian Journal of Agricultural Research, 39, 619-627. doi:10.1071/AR9880619
[24] Arbona, V., Iglesias, D.J., Jacas, J., Primo-Millo, E. and Talon, M. (2005) Hydrogel substrate amendment alleviates drought effects on young citrus plants. Plant Soil, 270, 73-82. doi:10.1007/s11104-004-1160-0
[25] Perez-Perez, J.G., Syvertsen, J.P., Botia, P. and Garcia-Sanchez, F. (2007) Leaf water relations and net gas exchange responses of salinized Carrizo citrange seedlings during drought stress and recovery. Annals of Botany, 100, 335-345. doi:10.1093/aob/mcm113
[26] Garcia-Sanchez, F., Syvertsen, J.P., Gimeno, V., Botia, P. and Perez-Perez, J.G. (2007) Responses to flooding and drought stress by two citrus rootstocks seedlings with different water-use efficiency. Physiology and Plantarum, 130, 532-542. doi:10.1111/j.1399-3054.2007.00925.x
[27] Busscher, W.J., Bjorneberg, D.L. and Sojka, R.E. (2009) Field application of PAM as an amendment in deep-tilled US southeastern coastal plain soils. Soil & Tillage Research, 104, 215-220. doi:10.1016/j.still.2009.02.009
[28] Goebel, M.O., Bachmann, J., Woche, S.K. and Fischer, W.R. (2005) Soil wettability, aggregate stability, and the decomposition of soil organic matter. Geoderma, 128, 80-93. doi:10.1016/j.geoderma.2004.12.016
[29] John, B., Yamashita, T., Ludwig, B. and Flessa, H. (2005) Storage of organic carbon in aggregate and density fractions of silty soils under different types of land use. Geoderma, 128, 63-79. doi:10.1016/j.geoderma.2004.12.013
[30] Dehgan, B., Yeager T.H. and Almira, F.C. (1994) Podocarpus growth response to a hydrophilic polymer- amended medium. Horticultural Science, 29, 641-644.
[31] Flannery, R.L. and Busscher, W.J. (1982) Use of a synthetic polymer in potting soil to improve water holding capacity. Soil Science and Plant Analysis, 13, 103-111. doi:10.1080/00103628209367249
[32] Sharma, J. (2004) Establishment of perennials in hydrophilic polymer amended soil. SNA Research Conference, 42, 30-532.
[33] Orikiriza, J.L.B., Agaba, H., Tweheyo, M., Eilu G., Kabasa, J.D. and Hutterman, A. (2009) Amending soils with hydrogels increases the biomass of nine tree species under non-water stress conditions. Clean—Soil, Air, Water, 37, 615-620. doi:10.1002/clen.200900128
[34] Hamilton, J.L. and Lowe, R.H. (1982) Use of a water absorbent polymer in tobacco seedling production and transplanting. Tobacco Science, 26, 17-20.
[35] Ma, H.C., and Nelles-Schwelm, E. (2004) Application of hydrogels for vegetation recovery in dry—Hot Valley of Yangtze. Yunnan Academy of Sciences, Yunnan.