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RESEARCH ARTICLE (Open Access)
Contents Vol 76(9)

Size matters: influence of dwarfing genes and the Lcol-A1 allele on coleoptile growth and crop establishment in wheat (Triticum aestivum)

Jordan A. Bathgate https://orcid.org/0009-0000-1795-5899 A B * , Juan S. Moroni A , Felicity A. J. Harris A B , Russell F. Eastwood C and Greg J. Rebetzke https://orcid.org/0000-0001-7404-0046 D
+ Author Affiliations
- Author Affiliations

A Gulbali Institute, Charles Sturt University, School of Agricultural, Environmental and Veterinary Sciences, Wagga Wagga, NSW 2678, Australia.

B NSW Department of Primary Industries and Regional Development, Wagga Wagga Agricultural Institute, Pine Gully Road, Wagga Wagga, NSW 2650, Australia.

C Australian Grain Technologies, Cheshire Street, Wagga Wagga, NSW 2650, Australia.

D CSIRO Agriculture and Food, PO Box 1700, Canberra, ACT 2601, Australia.

* Correspondence to: jbathgate@csu.edu.au

Handling Editor: Jairo Palta

Crop & Pasture Science 76, CP25101 https://doi.org/10.1071/CP25101
Submitted: 30 April 2025  Accepted: 9 August 2025  Published: 29 August 2025

© 2025 The Author(s) (or their employer(s)). Published by CSIRO Publishing. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)

Abstract

Context

Deep sowing allows growers to access deep soil moisture and ensure timely crop establishment in maximising yield potential. However, wheat cultivars containing the ‘Green Revolution’ Rht1 and Rht2 dwarfing genes often exhibit reduced crop establishment when sown deeper than 60 mm because of short coleoptile length (CL). Novel gibberellin biosynthetic mutant dwarfing genes associated with reduced plant height and greater CL offer potential alternatives to Rht1 and Rht2.

Aims

Determine CL and coleoptile diameter (CD) for genotypes and near-isogenic lines (NILs) with alternative dwarfing genes and a novel CL allele, and to validate plant establishment when sown deep in fields.

Methods

A diverse set of 101 wheat genotypes containing different dwarfing genes, including a novel long coleoptile allele, Lcol-A1, were assessed for CL and CD in temperature-controlled growth-chamber experiments (CE). The CE-phenotyped CL and CD were validated for plant establishment with shallow (4–5 cm) and deep (11–15 cm) sowing in two field experiments.

Key results

Compared with genotypes with Rht1 and Rht2, CL was significantly longer in genotypes with Rht13 (+23%), Rht18 (+24%), and Lcol-A1 (+16%) alleles across CE experiments. Longer CL significantly improved crop establishment with deep sowing in the field (16 and 33 plants m−2 for short- and long-coleoptiles respectively).

Conclusion

Longer CL associated with Rht13, Rht18 and Lcol-A1 allele improved crop establishment. Lcol-A1 allele was linked to a small increase in grain yield with deep sowing, while Rht18 was comparable to Rht2 with deep sowing.

Implications

Gibberellin-biosynthetic dwarfing genes, together with the Lcol-A1 allele, show promise for improving establishment with deep sowing.

Keywords: climate change, coleoptile diameter, coleoptile length, deep sowing, Lcol-A1, reduced height genes, Rht13, Rht18, seedling vigour, wheat.

References

Allan RE (1980) Influence of semidwarfism and genetic background on stand establishment of wheat. Crop Science 20(5), 634-638.
| Crossref | Google Scholar |

Allan RE, Vogel OA, Burleigh JR (1962) Length and estimated number of coleoptile parenchyma cells of six wheat selections grown at two temperatures. Crop Science 2(6), 522-524.
| Crossref | Google Scholar |

Anderson WK (1986) Some relationships between plant population, yield components and grain yield of wheat in a Mediterranean environment. Australian Journal of Agricultural Research 37(3), 219-233.
| Crossref | Google Scholar |

Anderson WK, Smith WR (1990) Yield advantage of two semi-dwarf compared with two tall wheats depends on sowing time. Australian Journal of Agricultural Research 41(5), 811-826.
| Crossref | Google Scholar |

Bhatt GM, Qualset CO (1976) Genotype–environment interactions in wheat: effects of temperature on coleoptile length. Experimental Agriculture 12(1), 17-22.
| Crossref | Google Scholar |

Borrill P, Mago R, Xu T, Ford B, Williams SJ, Derkx A, Bovill WD, Hyles J, Bhatt D, Xia X, MacMillan C, White R, Buss W, Molnár I, Walkowiak S, Olsen O-A, Doležel J, Pozniak CJ, Spielmeyer W (2022) An autoactive NB-LRR gene causes Rht13 dwarfism in wheat. Proceedings of the National Academy of Sciences 119(48), e2209875119.
| Crossref | Google Scholar |

Bovill WD, Hyles J, Zwart AB, Ford BA, Perera G, Phongkham T, Brooks BJ, Rebetzke GJ, Hayden MJ, Hunt JR, Spielmeyer W (2019) Increase in coleoptile length and establishment by Lcol-A1, a genetic locus with major effect in wheat. BMC Plant Biology 19(1), 332.
| Crossref | Google Scholar |

Butler D, Cullis B, Gilmour A, Gogel B, Thompson R (2017) ‘ASReml-R reference manual version 4.’ (VSN International: Hemel Hempstead, UK)

Ellis M, Spielmeyer W, Gale K, Rebetzke G, Richards R (2002) ‘Perfect’ markers for the Rht-B1b and Rht-D1b dwarfing genes in wheat. Theoretical and Applied Genetics 105, 1038-1042.
| Crossref | Google Scholar | PubMed |

Fletcher A, Lawes R, Weeks C (2016) Crop area increases drive earlier and dry sowing in Western Australia: implications for farming systems. Crop & Pasture Science 67(12), 1268-1280.
| Crossref | Google Scholar |

Flohr BM, Ouzman J, McBeath TM, Rebetzke GJ, Kirkegaard JA, Llewellyn RS (2021) Redefining the link between rainfall and crop establishment in dryland cropping systems. Agricultural Systems 190, 103-105.
| Crossref | Google Scholar |

Ford BA, Foo E, Sharwood R, Karafiatova M, Vrána J, MacMillan C, Nichols DS, Steuernagel B, Uauy C, Doležel J, Chandler PM, Spielmeyer W (2018) Rht18 semidwarfism in wheat is due to increased GA 2-oxidaseA9 expression and reduced GA content. Plant Physiology 177(1), 168-180.
| Crossref | Google Scholar | PubMed |

Gan Y, Stobbe EH, Moes J (1992) Relative date of wheat seedling emergence and its impact on grain yield. Crop Science 32(5), 1275-1281.
| Crossref | Google Scholar |

Gilmour AR, Cullis BR, Verbyla AP (1997) Accounting for natural and extraneous variation in the analysis of field experiments. Journal of Agricultural, Biological, and Environmental Statistics 2, 269-293.
| Crossref | Google Scholar |

Gooding S, Botwright Acuña TL, Fox PN, Wade LJ (2006) Emergence, stand establishment and vigour of deep-sown Australian and CIMMYT wheats. Australian Journal of Experimental Agriculture 46(9), 1167-1175.
| Crossref | Google Scholar |

GraphPad Prism (2020) ‘GraphPad Prism for Windows.’ Version 10.6.0. (GraphPad Software: Boston, MA, USA) Available at https://www.graphpad.com/

Hunt JR, Hayman PT, Richards RA, Passioura JB (2018) Opportunities to reduce heat damage in rain-fed wheat crops based on plant breeding and agronomic management. Field Crops Research 224, 126-138.
| Crossref | Google Scholar |

Kirkegaard JA, Hunt JR, McBeath TM, Lilley JM, Moore A, Verburg K, Robertson M, Oliver Y, Ward PR, Milroy S, Whitbread AM (2014) Improving water productivity in the Australian Grains industry – a nationally coordinated approach. Crop & Pasture Science 65(7), 583-601.
| Crossref | Google Scholar |

Lemerle D, Cousens RD, Gill GS, Peltzer SJ, Moerkerk M, Murphy CE, Collins D, Cullis BR (2004) Reliability of higher seeding rates of wheat for increased competitiveness with weeds in low rainfall environments. The Journal of Agricultural Science 142(4), 395-409.
| Crossref | Google Scholar |

Lutcher LK, Wuest SB, Johlke TR (2019) First leaf emergence force of three deep-planted winter wheat cultivars. Crop Science 59(2), 772-777.
| Crossref | Google Scholar |

Mahdi L, Bell CJ, Ryan J (1998) Establishment and yield of wheat (Triticum turgidum L.) after early sowing at various depths in a semi-arid Mediterranean environment. Field Crops Research 58(3), 187-196.
| Crossref | Google Scholar |

Matsui T, Inanaga S, Shimotashior T, An P, Sugimoto Y (2002) Morphological characters related to varietal differences in tolerance to deep sowing in wheat. Plant Production Science 5(2), 169-174.
| Crossref | Google Scholar |

Miralles DJ, Slafer GA (1991) A simple model for non-destructive estimates of leaf area in wheat. Cereal Research Communications 19, 439-444.
| Google Scholar |

Mohan A, Schillinger WF, Gill KS (2013) Wheat seedling emergence from deep planting depths and its relationship with coleoptile length. PLoS ONE 8(9), e73314.
| Crossref | Google Scholar |

R Core Team (2020) ‘R: a language and environment for statistical computing.’ (R Foundation for Statistical Computing: Vienna, Austria) Available at https://cran.r-project.org/

Radford BJ, Strong WM, Wilderminth GB (1989) Effects of urea and flutriafol on germination, coleptile length and establishment of wheat and barley. Australian Journal of Experimental Agriculture 29(4), 551-557.
| Crossref | Google Scholar |

Rebetzke GJ, Richards RA, Sirault XRR, Morrison AD (2004) Genetic analysis of coleoptile length and diameter in wheat. Australian Journal of Agricultural Research 55(7), 733-743.
| Crossref | Google Scholar |

Rebetzke GJ, Richards RA, Fettell NA, Long M, Condon AG, Forrester RI, Botwright TL (2007) Genotypic increases in coleoptile length improves stand establishment, vigour and grain yield of deep-sown wheat. Field Crops Research 100(1), 10-23.
| Crossref | Google Scholar |

Rebetzke GJ, Ellis MH, Bonnett DG, Condon AG, Falk D, Richards RA (2011) The Rht13 dwarfing gene reduces peduncle length and plant height to increase grain number and yield of wheat. Field Crops Research 124(3), 323-331.
| Crossref | Google Scholar |

Rebetzke GJ, Zheng B, Chapman SC (2016) Do wheat breeders have suitable genetic variation to overcome short coleoptiles and poor establishment in the warmer soils of future climates? Functional Plant Biology 43(10), 961-972.
| Crossref | Google Scholar | PubMed |

Rebetzke GJ, Rattey AR, Bovill WD, Richards RA, Brooks BJ, Ellis M (2022) Agronomic assessment of the durum Rht18 dwarfing gene in bread wheat. Crop & Pasture Science 73(4), 325-336.
| Crossref | Google Scholar |

Richards RA, Lukacs Z (2002) Seedling vigour in wheat-sources of variation for genetic and agronomic improvement. Australian Journal of Agricultural Research 53(1), 41-50.
| Crossref | Google Scholar |

Schillinger WF, Donaldson E, Allan RE, Jones SS (1998) Winter wheat seedling emergence from deep sowing depths. Agronomy Journal 90(5), 582-586.
| Crossref | Google Scholar |

Tang T, Botwright Acuña T, Spielmeyer W, Richards RA (2021) Effect of gibberellin-sensitive Rht18 and gibberellin-insensitive Rht-D1b dwarfing genes on vegetative and reproductive growth in bread wheat. Journal of Experimental Botany 72(2), 445-458.
| Crossref | Google Scholar | PubMed |

Tipton JL (1984) Evaluation of three growth curve models for germination data analysis. Journal of the American Society for Horticultural Science 109(4), 451-454.
| Crossref | Google Scholar |

VSN International (2020) ‘Genstat for Windows.’ 21st edn. (VSN International: Hemel Hempstead, UK) Available at Genstat.co.uk

Wang Y, Chen L, Du Y, Yang Z, Condon AG, Hu Y-G (2014) Genetic effect of dwarfing gene Rht13 compared with Rht-D1b on plant height and some agronomic traits in common wheat (Triticum aestivum L.). Field Crops Research 162, 39-47.
| Crossref | Google Scholar |

Wildermuth GB, McNamara RB, Quick JS (2001) Crown depth and susceptibility to crown rot in wheat. Euphytica 122(2), 397-405.
| Crossref | Google Scholar |

Zhao Z, Wang E, Kirkegaard JA, Rebetzke GJ (2022) Novel wheat varieties facilitate deep sowing to beat the heat of changing climates. Nature Climate Change 12(3), 291-296.
| Crossref | Google Scholar |