Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-11T04:50:08.679Z Has data issue: false hasContentIssue false

The effect of water stress on the temperature range for germination of Orobanche aegyptiaca seeds

Published online by Cambridge University Press:  22 February 2007

Ermias Kebreab
Affiliation:
Department of Agriculture, The University of Reading, Earley Gate, PO Box 236, Reading RG6 6AT, UK
Alistair J. Murdoch*
Affiliation:
Department of Agriculture, The University of Reading, Earley Gate, PO Box 236, Reading RG6 6AT, UK
*
*Correspondence Fax: +44 (0)118 931 8297 Email: A.J.Murdoch@reading.ac.uk

Abstract

Non-dormant seeds of Orobanche aegyptiaca were incubated at water potentials of 0 to –1.33 MPa and at constant temperatures from 5 to 29°C. Effects of water potential and temperature on final germination were modelled. In general, germination increased with increased temperature from 5 to 20°C and decreased above 26°C. Maximum germination occurred at 20–26°C and 0 MPa. Germination was reduced as the water potential decreased. Water potential also affected the temperature range over which high germination was observed; at 0 MPa high germination occurred over 9° (17–26°C) compared with 3° at -1.25 MPa (17–20°C). The optimum germination temperature also tended to decrease with a decrease in water potential. Final germination could be accounted for by seed-to-seed variation in the population assuming that each seed had a minimum temperature for germination and a maximum temperature above which it would not germinate. Seed-to-seed variation in these characteristics was assumed to be normally distributed, and it was further assumed that the two characteristics were independent. Effects of water potential on these temperature requirements were quantified, and the resulting empirical model accounted for final germination with reasonable accuracy (R2= 0.96).

Type
Research Article
Copyright
Copyright © Cambridge University Press 2000

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Akanda, R.U., Mullahey, J.J. and Shilling, D.G. (1996) Environmental factors affecting germination of tropical soda apple (Solanum viarum). Weed Science 44, 570574.CrossRefGoogle Scholar
Bierhuizen, J.F. and Wagenvoort, W.A. (1974) Some aspects of seed germination in vegetables 1. The determination and application of heat sums and minimum temperature for germination. Scientia Horticulturae 2, 213219.CrossRefGoogle Scholar
Bradford, K.J. (1990) A water relations analysis of seed germination rates. Plant Physiology 94, 840849.CrossRefGoogle ScholarPubMed
Bradford, K.J. (1995) Water relations in seed germination. pp. 351396in Kigel, J.; Galili, G. (Eds) Seed development and germination. New York, Marcel Dekker.Google Scholar
Bradford, K.J. (1997) The hydrotime concept in seed germination and dormancy. pp. 349360in Ellis, R.H.; Black, M.; Murdoch, A.J.; Hong, T.D. (Eds) Basic and applied aspects of seed biology. Dordrecht, Kluwer.CrossRefGoogle Scholar
Christensen, M., Meyer, S.E. and Allen, P.S. (1996) A hydrothermal time model of seed after-ripening in Bromus tectorum L. Seed Science Research 6, 155163.Google Scholar
Dahal, P. and Bradford, K.J. (1994) Hydrothermal time analysis of tomato seed germination at suboptimal temperature and reduced water potential. Seed Science Research 4, 7180.Google Scholar
Dahal, P., Bradford, K.J. and Haigh, A.M. (1993) The concept of hydrothermal time in seed germination and priming. pp. 10091014in Côme, D.; Corbineau, F. (Eds) Basic and applied aspects of seed biology. Proceedings of the fourth international workshop on seeds. Paris, ASFIS.Google Scholar
Dahal, P., Kim, N.S. and Bradford, K.J. (1996) Respiration and germination rates of tomato seeds at suboptimal temperatures and reduced water potentials. Journal of Experimental Botany 47, 941947.CrossRefGoogle Scholar
Ellis, R.H., Simon, G. and Covell, S. (1987) The influence of temperature on seed germination rate in grain legumes. III. A comparison of five faba bean genotypes at constant temperatures using a new screening method. Journal of Experimental Botany 38, 10331043.CrossRefGoogle Scholar
Emmerich, W.E. and Hardegree, S.P. (1990) Polyethylene glycol solution contact effects on seed germination. Agronomy Journal 82, 11031107.CrossRefGoogle Scholar
Falleri, E. (1994) Effect of water stress on germination in six provenances of Pinus pinaster Ait. Seed Science and Technology 22, 591599.Google Scholar
Foy, C.L., Jacobsohn, R., Bohlinger, B. and Jacobsohn, M. (1991) Seasonal behaviour of broomrape species as determined by host range and environmental factors. pp. 454457in Ransom, J.K.; Musselman, L.J.; Worsham, A.O.; Parker, C. (Eds) Proceedings of the fifth international symposium in parasitic weeds. Nairobi, CIMMYT.Google Scholar
Gan, Y.T., Stobbe, E.H. and Njue, C. (1996) Evaluation of selected non-linear regression models in quantifying seedling emergence rate of spring wheat. Crop Science 36, 165168.CrossRefGoogle Scholar
Garcia-Huidobro, J., Monteith, J.L. and Squire, G.R. (1982) Time, temperature and germination of pearl millet (Pennisetum typhoides S. & H.) I. Constant temperature. Journal of Experimental Botany 33, 288296.CrossRefGoogle Scholar
Genstat 5 Committee (1994) Genstat 5 Release 3 Reference Manual. Oxford, Clarendon Press.Google Scholar
Grundy, A.C. (1997) The influence of temperature and water potential on the germination of seven different drystored seed lots of Stellaria media. Weed Research 37, 257266.CrossRefGoogle Scholar
Gummerson, R.J. (1986) The effect of constant temperatures and osmotic potentials on the germination of sugar beet. Journal of Experimental Botany 37, 729741.CrossRefGoogle Scholar
Joel, D.M., Back, A., Kleifeld, Y. and Gepstein, S. (1991) Seed conditioning and its role in Orobanche seed germination: Inhibition by paclobutrazol. pp. 147156in Wegman, K.; Musselman, L.J. (Eds) Progress in Orobanche research. Proceedings of the international workshop on Orobanche research. Tübingen, Eberhard-Karls-Universität.Google Scholar
Kebreab, E. and Murdoch, A.J. (1999a) A quantitative model for loss of primary dormancy and induction of secondary dormancy in imbibed seeds of Orobanche spp. Journal of Experimental Botany 50, 211219.CrossRefGoogle Scholar
Kebreab, E. and Murdoch, A.J. (1999b) Modelling the effects of water stress and temperature on germination rate of Orobanche aegyptiaca seeds. Journal of Experimental Botany 50, 655664.Google Scholar
Kebreab, E. and Murdoch, A.J. (1999c) A model of the effects of a wide range of constant and alternating temperatures on seed germination of four Orobanche species. Annals of Botany 84, 549557.CrossRefGoogle Scholar
King, C.A. and Oliver, L.R. (1994) A model for predicting large crabgrass (Digitaria sanguinalis) emergence as influenced by temperature and water potential. Weed Science 42, 561567.CrossRefGoogle Scholar
Linke, K.H. (1987) Untersuchungen über keimung und jugendentwicklung von Striga und Orobanche. PLITS 5, 195. Hohenheim, Germany, Universität Hohenheim.Google Scholar
Michel, B.E. (1983) Evaluation of the water potentials of solutions of polyethylene glycol 8000 both in the absence and presence of other solutes. Plant Physiology 72, 6670.CrossRefGoogle ScholarPubMed
Michel, B.E. and Kaufmann, M.R. (1973) The osmotic potential of polyethylene glycol 6000. Plant Physiology 51, 914916.CrossRefGoogle ScholarPubMed
Murdoch, A.J., Roberts, E.H. and Goedert, C.O. (1989) A model for germination responses to alternating temperatures. Annals of Botany 63, 97111.CrossRefGoogle Scholar
Van Hezewijk, M.J., Verkleij, J.A.C. and Pieterse, A.H. (1991) Temperature dependence of germination in Orobanche crenata. pp. 125133in Wegman, K.; Musselman, L.J. (Eds) Progress in Orobanche research. Proceedings of the international workshop on Orobanche research. Tübingen, Eberhard-Karls-Universität.Google Scholar
Weldeghiorghis, E.K. and Murdoch, A.J. (1996) Germination of Orobanche crenata seeds at a wide range of alternating and constant temperatures. pp. 425431in Moreno, M.T.; Cubero, J.I.; Berner, D.; Joel, D.; Musselman, L.J.; Parker, C. (Eds) Advances in parasitic plant research. Proceedings of the sixth international parasitic weed symposium. Cordoba, Dirección General De Investigación Agraria De Andalucia.Google Scholar