Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-11-20T03:28:36.807Z Has data issue: false hasContentIssue false
  • English
  • Français

Coat thickness and hard-seededness in some Medicago and Trifolium species

Published online by Cambridge University Press:  19 September 2008

L. Russi ,
P. S. Cocks  and
E. H. Roberts
L. Russi*
Affiliation:
International Center for Agricultural Research in the Dry Areas (ICARDA), PO Box 5466, Aleppo, Syria
P. S. Cocks
Affiliation:
International Center for Agricultural Research in the Dry Areas (ICARDA), PO Box 5466, Aleppo, Syria
E. H. Roberts
Affiliation:
Department of Agriculture, University of Reading, Earley Gate, PO Box 236, Reading RG6 2AT, UK
*
* Present address and correspondence Istituto di Miglioramento Genetico Vegetale, Universita di Perugia, Borgo XX Giugno, 74 06100 Perugia, Italy
Get access Rights & Permissions [Opens in a new window]

Abstract

The seeds of three medics (Medicago orbicularis, M. rigidula and M. rotata) and three clovers (Trifolium stellatum, T. campestre and T. tomentosum) were collected from a pasture in north-west Syria on three occasions: immediately after seed set, at the end of the dry season, i.e. 4 months after seed set, and 16 months after seed set. Complete and sectioned seeds were observed with a scanning electron microscope. Morphological changes and differences in thickness of the seed coat were related to the hard-seededness of the samples collected in the seed bank before the onset of the rainy season. The morphology and structure of the seed coat of all six species were typical of papilionoid legumes. The species with the softest seeds (T. stellatum) showed a very thin and discontinuous cuticular layer at seed maturation (0.16 μm), while a thick and continuous cuticle (4.24 μm) was characteristic of the hardest-seeded species (M. orbicularis). The lens region of seed of all species except T. campestre was weakened after a few months in the field. This weakening was also found in seeds which were certainly hard, but the cracks in the lens region were apparently not deep enough to allow imbibition. Even when large areas of the palisade layer were removed from the lens region of seeds of M. rotata, this was not sufficient to permit water uptake. Differences in the seed coat thickness of the six species accounted for differences in seed dormancy only when seed mass was taken into account.

Keywords

hard seedsMedicagopasture legumesscanning microscopyseed coatTrifolium
Type
Research Papers
Information
Seed Science Research , Volume 2 , Issue 4 , December 1992 , pp. 243 - 249
Copyright
Copyright © Cambridge University Press 1992

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.)

Footnotes

†

Present address Crop and Pasture Science Department, University of Western Australia, Nedlands, Perth WA 6009, Australia

References

Aitken, Y. (1939) The problem of hard seeds in subterranean clover. Proceedings of the Royal Society of Victoria 51, 187–213.Google Scholar
Baciu-Miclaus, D. (1970) Contribution to the study of hard seed and coat structure properties of soybean. Proceedings of the International Seed Testing Association 35, 599–617.Google Scholar
Ballard, L.A.T. (1973) Physical barriers to germination. Seed Science and Technology 1, 285–303.Google Scholar
Ballard, L.A.T. (1976) Strophiolar water conduction in seeds of the Trifolieae induced by action on the testa at non-strophiolar sites. Australian Journal of Plant Physiology 3, 465–469.Google Scholar
Ballard, L.A.T. and Grant Lipp, A.E. (1965) Germination of subterranean clover seeds in relation to some softening procedures. Proceedings of the International Seed Testing Association 30, 893–904.Google Scholar
Bennett, H.W. (1959) The effectiveness of selection for the hard seed character in crimson clover. Agronomy Journal 51, 15–16.CrossRefGoogle Scholar
Bhalla, P.L. and Slattery, H.D. (1984) Callose deposits make clover seeds impermeable to water. Annals of Botany 53, 125–128.CrossRefGoogle Scholar
Crawford, E.J. (1976) The search for permeable seed in species of the genus Medicago. Australian Seed Science Newsletter 2, 21–24.Google Scholar
Donnelly, E.D. (1970) Persistence of hard seed in Vicia lines derived from interspecific hybridization. Crop Science 10, 661–662.CrossRefGoogle Scholar
Donnelly, E.D. (1971) Breeding hard-seeded vetch using interspecific hybridization. Crop Science 11, 721–724.CrossRefGoogle Scholar
Egley, G.H., Paul, R.N. Jr., Vaughn, K.C. and Duke, S.O. (1983) Role of peroxidase in the development of water-impermeable seed coats in Sida spinosa L. Planta 157, 224–232.CrossRefGoogle ScholarPubMed
Esau, K. (1977) Anatomy of seed plants. New York, John Wiley and Sons.Google Scholar
Gunn, C.R. (1981) Seeds of Leguminosae. pp. 913–925 in Polhill, R.M. and Raven, P.H. (Eds) Advances in legume systematics. London, Royal Botanic Gardens, Kew.Google Scholar
Gutterman, Y. (1979) Seed coat permeability as a function of photoperiodical treatments of the mother plants during seed maturation in the desert annual plant: Trigonella arabica, Del. Journal of Arid Environments 1, 141–144.CrossRefGoogle Scholar
Gutterman, Y. and Heydecker, W. (1973) Studies of the surface of desert plant seeds. I. Effect of day length upon maturation of the seed coat of Ononis sicula Guss. Annals of Botany 37, 1049–1050.CrossRefGoogle Scholar
Hagon, M.W. and Ballard, L.A.T. (1970) Reversibility of strophiolar permeability to water in seeds of subterranean clover (Trifolium subterraneum L.). Australian Journal of Biological Science 23, 519–528.CrossRefGoogle Scholar
Hamly, D.H. (1932) Softening of the seeds of Melilotus alba. Botanical Gazette 93, 345–375.CrossRefGoogle Scholar
Hyde, E.O.C. (1954) The function of the hilum in some Papilionaceae in relation to the ripening of the seed and the permeability of the testa. Annals of Botany 18, 241–256.CrossRefGoogle Scholar
Lebedeff, G.A. (1947) Studies on the inheritance of hard seeds in beans. Journal of Agricultural Research 74, 205–215.Google Scholar
Loftus Hills, K. (1944) Dormancy and hardseededness in T(rifolium) subterraneum L. Parts 2–6. Journal of the Council for Scientific and Industrial Research 17, 186–190, 191–196, 242–250, 251–254, 255–257.Google Scholar
Lush, W.M. and Evans, L.T. (1980) The seed coat of cowpeas and other grain legumes: structure in relation to function. Field Crops Research 3, 267–286.CrossRefGoogle Scholar
Marbach, I. and Mayer, A.M. (1974) Permeability of seed coats to water as related to drying conditions and metabolism of phenolics. Plant Physiology 54, 817–820.CrossRefGoogle ScholarPubMed
McKee, G.W., Pfeiffer, R.A. and Mohsenin, N.N. (1977) Seedcoat structure in Coronilla varia L. and its relations to hard seed. Agronomy Journal 69, 53–58.CrossRefGoogle Scholar
Quinlivan, B.J. (1971) Seed coat impermeability in legumes. Journal of the Australian Institute of Agricultural Science 37, 283–295.Google Scholar
Russi, L., Cocks, P.S. and Roberts, E.H. (1992) Hardseededness and seed bank dynamics of six pasture legumes. Seed Science Research 2, 231–241.CrossRefGoogle Scholar
Saunders, D.A. (1981) Investigation into seed coat impermeability in annual Medicago species. Ph.D. thesis, University of Reading, UK.Google Scholar
Tran, V.N. (1979) Effects of microwave energy on the strophiole, seed coat and germination of Acacia seeds. Australian Journal of Plant Physiology 6, 277–287.Google Scholar
Tran, V.N. and Cavanagh, A.K. (1980) Taxonomic implications of fracture load and deformation histograms and the effect of treatments on the impermeable seed coat of Acacia species. Australian Journal of Botany 28, 39–51.CrossRefGoogle Scholar
Tran, V.N. and Cavanagh, A.K. (1984) Structural aspects of dormancy. pp. 1–44 in Murray, D.R. (Ed.) Seed physiology. Vol. 2. Germination and reserve mobilization. Australia, Academic Press.Google Scholar
Watson, D.P. (1948) Structure of the testa and its relation to germination in the Papilionaceae tribes Trifoliae and Loteae. Annals of Botany 12, 385–409.CrossRefGoogle Scholar
Werker, E. (1980/1981) Seed dormancy as explained by anatomy of embryo envelopes. Israel Journal of Botany 29, 22–44.Google Scholar
Werker, E., Dafni, A. and Negbi, M. (1973) Variability in Prosopis falcata in Israel: anatomical features of the seed. Botanical Journal of the Linnean Society 66, 223–232.CrossRefGoogle Scholar
Werker, E., Marbach, I. and Mayer, A.M. (1979) Relationship between the anatomy of the testa, water permeability and the presence of phenolics in the genus Pisum. Annals of Botany 43, 765–771.CrossRefGoogle Scholar