Grevillea (Proteaceae) seed coats contain inhibitors for seed germination
Xuanli Ma A , Jingnan Guo A B , Xinyan Han A C and Guijun Yan A DA School of Plant Biology, Faculty of Science and The UWA Institute of Agriculture, The University of Western Australia, Crawley, WA 6009, Australia.
B Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Hanghai East Road, Zhengzhou, Henan 450009, P. R. China.
C Shanxi Academy of Agriculture, 21 Xutan East Street, Taiyuan, Shanxi 030000, P. R. China.
D Corresponding author. Email: guijun.yan@uwa.edu.au
Australian Journal of Botany 63(7) 566-571 https://doi.org/10.1071/BT15085
Submitted: 6 April 2015 Accepted: 3 July 2015 Published: 10 August 2015
Abstract
The purpose of this research was to examine the effect of the seed coat on seed dormancy in Grevillea (Proteaceae) species, and to further investigate the existence of germination inhibitors in Grevillea seed coat extracts. Seed dormancy of 18 Grevillea accessions involving 17 species was investigated: results indicated that removal of seed coat increased seed germination from 0–6% (intact seeds) to 83–100% for the Grevillea accessions and removal of half seed coat resulted in no increase in seed germination. Grevillea seed coat extracts reduced germination of barley, canola, lupin and ryegrass seeds by 48, 57, 10 and 38% respectively. The extracts also reduced seedling growth of the above four species. Ryegrass seeds showed no germination on the 3rd day after imbibition in the presence of Grevillea seed coat extracts compared with 88% germination for the control. Thus, our results showed that seed coat is a major factor determining Grevillea seed dormancy and removal of seed coat dramatically increased seed germination. Grevillea seed coat extracts reduced seed germination and seedling growth of other species. We conclude that there is exogenous seed dormancy in Grevillea species and the chemical(s) in the seed coat is a major factor inhibiting seed germination.
References
Abu-Shakra S, Aqil BA (1969) Effect of water extract of sugarbeet on the germination of other crop seeds. Journal of the American Society of Sugar Beet Technologist 15, 5Baker KS, Steadman KJ, Plummer JA, Dixon KW (2005) Seed dormancy and germination responses of nine Australian fire ephemerals. Plant and Soil 277, 345–358.
| Seed dormancy and germination responses of nine Australian fire ephemerals.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXht1GlsLrF&md5=3f01fb3cd89bc1474d83c1a746db4aadCAS |
Baskin CC, Baskin JM (1998) ‘Seeds: ecology, biogeography, and evolution of dormancy and germination.’ (Academic Press: San Diego, CA, USA)
Baskin JM, Baskin CC (2004) A classification system for seed dormancy. Seed Science Research 14, 16
| A classification system for seed dormancy.Crossref | GoogleScholarGoogle Scholar |
Bewley JD, Black M (1994) ‘Seeds: physiology of development and germination.’ (Plenum Press: New York)
Briggs CL, Morris EC (2008) Seed coat dormancy in Grevillea linearifolia: little change in permeability to an apoplastic tracer after treatment with smoke and heat. Annals of Botany 101, 623–632.
| Seed coat dormancy in Grevillea linearifolia: little change in permeability to an apoplastic tracer after treatment with smoke and heat.Crossref | GoogleScholarGoogle Scholar | 18250110PubMed |
Chen S-Y, Chien C-T, Chung J-D, Yang Y-S, Kuo S-R (2007) Dormancy-break and germination in seeds of Prunus campanulata (Rosaceae): role of covering layers and changes in concentration of abscisic acid and gibberellins. Seed Science Research 17, 21–32.
| Dormancy-break and germination in seeds of Prunus campanulata (Rosaceae): role of covering layers and changes in concentration of abscisic acid and gibberellins.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXntlOisL4%3D&md5=9a9ea941418b4bc588394a2e74d54bd4CAS |
Dixon KW, Roche S, Pate JS (1995) The promotive effect of smoke derived from burnt native vegetation on seed germination of Western Australian plants. Oecologia 101, 185–192.
| The promotive effect of smoke derived from burnt native vegetation on seed germination of Western Australian plants.Crossref | GoogleScholarGoogle Scholar |
Edwards W, Whelan R (1995) The size, distribution and germination requirements of the soil-stored seed-bank of Grevillea barklyana (Proteacea). Australian Journal of Ecology 20, 7
Egerton-Warburton LM, Ghisalberti EL (2001) Isolation and structural identification of a germination inhibitor in fire-recruiters from the California chaparral. Journal of Chemical Ecology 27, 371–382.
| Isolation and structural identification of a germination inhibitor in fire-recruiters from the California chaparral.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXjsl2qtb0%3D&md5=26f97777a82aa0940f3f0dbea63ba8e4CAS | 14768821PubMed |
Flematti GR, Ghisalberti EL, Dixon KW, Trengove RD (2004) A compound from smoke that promotes seed germination. Science 305, 977
| A compound from smoke that promotes seed germination.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXmslWqtrs%3D&md5=9fb69d429e947ff7779a8f1540a4d5e1CAS | 15247439PubMed |
Guo J, Ma X, Yan G (2010) Seed coat removal greatly enhances Grevillea (Proteaceae) seed germination. In ‘The 28th International Horticultural Congress, Lisbon, Portugal’.
Kenny BJ (2000) Influence of multiple fire-related germination cues on three Sydney Grevillea (Proteaceae) species. Austral Ecology 25, 664–669.
| Influence of multiple fire-related germination cues on three Sydney Grevillea (Proteaceae) species.Crossref | GoogleScholarGoogle Scholar |
Makinson PO (2000) ‘Grevillea. Flora of Australia, 17A Proteaceae.’ (CSIRO Publishing: Melbourne)
Morris EC (2000) Germination response of seven east Australian Grevillea species (Proteaceae) to smoke, heat exposure and scarification. Australian Journal of Botany 48, 179–189.
| Germination response of seven east Australian Grevillea species (Proteaceae) to smoke, heat exposure and scarification.Crossref | GoogleScholarGoogle Scholar |
Morris EC, Tieu A, Dixon K (2000) Seed coat dormancy in two species of Grevillea (Proteaceae). Annals of Botany 86, 771–775.
| Seed coat dormancy in two species of Grevillea (Proteaceae).Crossref | GoogleScholarGoogle Scholar |
Nelson DC, Riseborough J-A, Flematti GR, Stevens J, Ghisalberti EL, Dixon KW, Smith SM (2009) Karrikins discovered in smoke trigger Arabidopsis seed germination by a mechanism requiring gibberellic acid synthesis and light. Plant Physiology 149, 863–873.
| Karrikins discovered in smoke trigger Arabidopsis seed germination by a mechanism requiring gibberellic acid synthesis and light.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXjt1Wqu7s%3D&md5=59be608efa8f05a9af1f010d9173d024CAS | 19074625PubMed |
Nikolaeva MG (1977) Factors controlling the seed dormancy pattern. In ‘The physiology and biochemistry of seed dormancy and germination’. (Ed. AA Khan) pp. 51–74. (North-Holland Publishing Company: New York)
Olde P, Marriott N (1995) ‘The Grevillea book.’ (Kangaroo Press Ltd: Kenthurst, NSW)
Ren C, Kermode AR (1999) Analyses to determine the role of the megagametophyte and other seed tissues in dormancy maintenance of yellow cedar (Chamaecyparis nootkatensis) seeds: morphological, cellular and physiological changes following moist chilling and during germination. Journal of Experimental Botany 50, 1403–1419.
Roche S, Koch JM, Dixon KW (1997) Smoke enhanced seed germination for mine rehabilitation in the southwest of Western Australia. Restoration Ecology 5, 191–203.
| Smoke enhanced seed germination for mine rehabilitation in the southwest of Western Australia.Crossref | GoogleScholarGoogle Scholar |
Schwachtje J, Baldwin IT (2004) Smoke exposure alters endogenous gibberellin and abscisic acid pools and gibberellin sensitivity while eliciting germination in the post-fire annual, Nicotiana attenuata. Seed Science Research 14, 9
| Smoke exposure alters endogenous gibberellin and abscisic acid pools and gibberellin sensitivity while eliciting germination in the post-fire annual, Nicotiana attenuata.Crossref | GoogleScholarGoogle Scholar |
