Hostname: page-component-cd9895bd7-jkksz Total loading time: 0 Render date: 2024-12-22T20:03:07.923Z Has data issue: false hasContentIssue false
  • English
  • Français

Seed Dormancy and Seedling Emergence in Ripgut Brome (Bromus diandrus) Populations in Southern Australia

Published online by Cambridge University Press:  20 January 2017

Samuel George Lloyd Kleemann  and
Gurjeet Singh Gill
Samuel George Lloyd Kleemann*
Affiliation:
School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, South Australia, Australia 5064
Gurjeet Singh Gill
Affiliation:
School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, South Australia, Australia 5064
*
Corresponding author's E-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

Ripgut brome is a difficult weed to manage in cereal crops of southern Australia because only a few herbicides can provide effective control in cereals. Knowledge of seed-dormancy mechanisms, germination ecology, and emergence behavior in the field could facilitate development of effective weed control programs for this weed species. Ripgut brome populations from cropping fields were found to possess much longer seed dormancy than that reported previously in the literature. Furthermore, some ripgut brome populations from cropping fields showed longer seed dormancy than those collected from adjacent noncropped fence lines. For example, all seeds of one of the populations from the fence line (SA-1F) germinated at 3 mo after maturity, whereas seeds from the cropping field at the same site (SA-1C) showed little germination (< 3%) even at 8 mo after maturity. These highly dormant ripgut brome populations from cropping fields were responsive to cold stratification, with germination increasing significantly after 2 to 14 d of exposure. Germination of dormant ripgut brome populations increased with addition of gibberellic acid (0.001 M GA3), particularly when lemma and palea had been removed. Ripgut brome populations from cropping fields (VIC-2C and SA-1C) showed strong inhibition of seed germination when exposed to light. These differences in seed dormancy among ripgut brome populations were also expressed in seedling emergence pattern in the field. The nondormant populations collected from fence lines showed high seedling establishment (> 80%) during autumn, which coincided with the planting time of winter crops in southern Australia. In contrast, five populations from cropping fields showed much lower seedling establishment (3 to 17%) before the time of crop planting. Delayed seedling establishment in populations from cropping fields could lead to less effective preseeding weed control and higher weed infestations in field crops. Results of this study also showed that the seedbank of these highly dormant ripgut brome populations can readily persist from one year to the next. Effective management of ripgut brome populations with long seed dormancy and increased seedbank persistence would require a major change in cropping systems used by the growers in southern Australia.

Keywords

Ripgut brome, Bromus diandrus RothCold stratificationgibberellic acidlightseedbank persistence
Type
Weed Biology and Ecology
Information
Weed Science , Volume 61 , Issue 2 , June 2013 , pp. 222 - 229
Copyright
Copyright © Weed Science Society of America 

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

Literature Cited

Chauhan, B. S., Gill, G., and Preston, C. 2006. Factors affecting seed germination of threehorn bedstraw (Galium tricornutum) in Australia. Weed Sci. 54: 471–77.Google Scholar
Cheam, A. H. 1986. Patterns of change in seed dormancy and persistence of Bromus diandrus Roth (Great Brome) in the field. Aust. J. Agric. Res. 37: 471–81.Google Scholar
Del Monte, J. P. and Dorado, J. 2011. Effects of light conditions and after-ripening time on seed dormancy loss of Bromus diandrus Roth. Weed Res. 51: 581–590.Google Scholar
Finkelstein, R., Reeves, W., Ariizumi, T., and Steber, C. 2008. Molecular aspects of seed dormancy. Annu. Rev. Plant Biol. 59: 387–415.Google Scholar
Fleet, B. and Gill, G. 2012. Seed dormancy and seedling recruitment in smooth barley (Hordeum murinum spp. glaucum) populations in southern Australia. Weed Sci. 60: 394–400.Google Scholar
Gill, G. S. and Blacklow, W. M. 1984. Effect of great brome (Bromus diandrus Roth.) on the growth of wheat and great brome and their uptake of nitrogen and phosphorus. Aust. J. Agric. Res. 35: 1–8.Google Scholar
Gill, G. S. and Blacklow, W. M. 1985. Variations in seed dormancy and rates of development of great brome, Bromus diandrus Roth., as adaptations to the climates of Southern Australia and implications for weed control. Aust. J. Agric. Res. 36: 295–304.Google Scholar
Gill, G. S. and Carstairs, S. A. 1988. Morphological, cytological and ecological discrimination of Bromus rigidus and Bromus diandrus . Weed Res. 28: 399–405.Google Scholar
Harradine, A. R. 1986. Seed longevity and seedling establishment of Bromus diandrus Roth. Weed Res. 26: 173–180.Google Scholar
Kleemann, S.G.L. and Gill, G. S. 2006. Differences in the distribution and seed germination behaviour of populations of Bromus rigidus and Bromus diandrus in South Australia: adaptations to habitat and implications for weed management. Aust. J. Agric. Res. 57: 213–219.Google Scholar
Kleemann, S.G.L. and Gill, G. S. 2009. Population ecology and management of rigid brome (Bromus rigidus) in Australian cropping systems. Weed Sci. 57: 202–207.Google Scholar
Kon, K. F. and Blacklow, W. M. 1988. Identification, distribution and population variability of great brome (Bromus diandrus Roth.) and rigid brome (Bromus rigidus Roth.). Aust. J. Agric. Res. 39: 1039–1050.Google Scholar
Kon, K. F. and Blacklow, W. M. 1995. Bromus diandrus Roth and Bromus rigidus Roth. Pages 13–27 in Groves, R., Shepherd, R., and Richardson, R., eds. The Biology of Australian Weeds, Volume 1. Melbourne, Australia: R.G. and F.J. Richardson.Google Scholar
Naylor, J. M. and Jana, S. 1976. Genetic adaptation for seed dormancy in Avena fatua . Can. J. Bot. 54: 306–312.Google Scholar
Payne, R. W., Murray, D. A., Harding, S. A., Baird, D. B., and Soutar, D. M. 2007. GenStat for Windows. Reference Manual. 10th ed. Hemel Hempstead, UK. VSN International.Google Scholar
Smith, P. M. 1980. Bromus . Pages 182–189 in Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M., and Webb, D. A., editors. Flora Europaea. Alismataceae to Orchidaceae (Monocotyledones), Volume 5. Cambridge, UK: Cambridge University Press.Google Scholar
Steadman, K. J., Bignell, G. P., and Ellery, A. J. 2003. Field assessment of thermal after-ripening time for dormancy release prediction in Lolium rigidum seeds. Weed Res. 43: 458–465.Google Scholar
Yamauchi, Y., Ogawa, M., Kuwahara, A., Hanada, A., Kamiya, Y., and Yamaguchi, S. 2004. Activation of gibberellins biosynthesis and response pathways by low temperature during imbibitions of Arabidopsis thaliana seeds. Plant Cell 16: 367–378.Google Scholar