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Downy Brome (Bromus tectorum) Vernalization: Variation and Genetic Controls

  • Nevin C. Lawrence (a1), Amber L. Hauvermale (a2) and Ian C. Burke (a3)


Downy brome (Bromus tectorum L.) is a widely distributed invasive winter annual grass across western North America. Bromus tectorum phenology can vary considerably among populations, and those differences are considered adaptively significant. A consensus hypothesis in the literature attributes the majority of observed differences in B. tectorum phenology to differing vernalization requirements among populations. A series of greenhouse experiments were conducted to identify differences in B. tectorum vernalization requirements and link vernalization to expression of annual false-brome [Brachypodium distachyon (L.) P. Beauv.]-derived vernalization gene homolog (BdVRN1). Results from this study indicate that variation in time to flowering is partially governed by differing vernalization requirements and that flowering is linked to the expression of BdVRN1.


Corresponding author

Author for correspondence: Nevin C. Lawrence, Department of Agronomy and Horticulture, University of Nebraska-Lincoln, 4502 Avenue I, Scottsbluff, NE 69361. (E-mail:


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Ball, DA, Frost, SM, Gitelman, AI (2004) Predicting timing of downy brome (Bromus tectorum) seed production using growing degree days. Weed Sci 52:518524
Chen, A, Dubcovsky, J (2012) Wheat TILLING mutants show that the vernalization gene VRN1 down-regulates the flowering repressor VRN2 in leaves but is not essential for flowering. PLoS Genet 8:113
Chouard, P (1960) Vernalization and its relations to dormancy. Annu Rev Plant Physiol 11:191238
Cockram, J, Chiapparino, E, Taylor, SA, Stamati, K, Donini, P, Laurie, DA, O’Sullivan, DM (2007) Haplotype analysis of vernalization loci in European barley germplasm reveals novel VRN-H1 alleles and a predominant winter VRN-H1/VRN-H2 multi-locus haplotype. Theor Appl Genet 115:9931001
Fu, D, Szucs, P, Yan, L, Helguera, M, Skinner, JS, Von Zitzewitz, J, Hayes, PM, Dubcovsky, J (2005) Large deletions within the first intron in VRN-1 are associated with spring growth habit in barley and wheat. Mol Genet Genomics 273:5465
Greenup, A, Peacock, WJ, Dennis, ES, Trevaskis, B (2009) The molecular biology of seasonal flowering-responses in Arabidopsis and the cereals. Ann Bot 103:11651172
Hemming, MN, Peacock, WJ, Dennis, ES, Trevaskis, B (2008) Low-temperature and daylength cues are integrated to regulate FLOWERING LOCUS T in barley. Plant Physiol 147:355366
Hong, SY, Seo, PJ, Yang, MS, Xiang, F, Park, CM (2008) Exploring valid reference genes for gene expression studies in Brachypodium distachyon by real-time PCR. BMC Plant Biol 8:112
Hulbert, L (1955) Ecological studies of Bromus tectorum and other annual bromegrasses. Ecol Monogr 25:181213
Klemmedson, JO, Smith, JG (1964) Cheatgrass (Bromus tectorum L.). Bot Rev 30:226262
Lawrence, NC, Hauvermale, AL, Dhingra, A, Burke, IC (2017) Population structure and genetic diversity of Bromus tectorum within the small grain production region of the Pacific Northwest. Ecol Evol 7:83168328
Martin, R, Liu, P, Nonogaki, H (2005) Simple purification of small RNAs from seeds and efficient detection of multiple microRNAs expressed in Arabidopsis thaliana and tomato (Lycopersicon esculentum) seeds. Seed Sci Res 15:319328
Meyer, SE, Nelson, DL, Carlson, SL (2004) Ecological genetics of vernalization response in Bromus tectorum L. (Poaceae). Ann Bot 93:653663
Morrow, LA, Stahlman, PW (1984) The history and distribution of downy brome (Bromus tectorum) in North America. Weed Sci 32(Suppl 1):26
Novak, S, Mack, R, Soltis, P (1993) Genetic variation in Bromus tectorum (Poaceae): introduction dynamics in North America. Can J Bot 71:14411448
Oliver, SN, Finnegan, EJ, Dennis, ES, Peacok, WJ, Trevaskis, B (2009) Vernalization-induced flowring in cereals is associated with changes in histone methylation at the VERNALIZATION1 gene. Proc Natl Acad Sci USA 106:83868391
Ornate-Sanchez, L, Vicente-Carajosa, J (2008) DNA-free RNA isolation protocols for Arabidopsis thaliana, including seeds and siliques. BMC Res Notes 1:93
R Core Team (2013) R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria.
Ramakrishnan, AP, Meyer, SE, Fairbanks, DJ, Coleman, CE (2006) Ecological significance of microsatellite variation in western North American populations of Bromus tectorum . Plant Species Biol 21:6173
Ream, TS, Woods, DP, Schwartz, CJ, Sanabria, CP, Mahoy, JA, Walters, EM, Kaeppler, HF, Amasino, RM (2014) Interaction of photoperiod and vernalization determines flowering time of Brachypodium distachyon . Plant Physiol 164:694709
Rice, K, Mack, R (1991a) Ecological genetics of Bromus tectorum. I. A hierarchical analysis of phenotypic variation. Oecologia 88:7783
Rice, KJ, Mack, RN (1991b) Ecological genetics of Bromus tectorum. III. The demography of reciprocally sown populations. Oecologia 88:91101
Ritz, C, Streibig, JC (2005) Bioassay analysis using R. J Stat Softw 12:122
Schwartz, CJ, Doyle, MR, Manzaneda, AJ, Rey, PJ, Mitchell-Olds, T, Amasino, RM (2010) Natural variation of flowering time and vernalization responsiveness in Brachypodium distachyon . BioEnergy Res 3:3846
Scott, JW, Meyer, SE, Merrill, KR, Anderson, VJ (2010) Local population differentiation in Bromus tectorum L. in relation to habitat-specific selection regimes. Evol Ecol 24:10611080
Soreng, RJ, Peterson, PM, Romaschenko, K, Davidse, G, Zuloaga, FO, Judziewicz, EJ, Filgueiras, TS, Davis, JI, Morrone, O (2015) A worldwide phylogenetic classification of the Poaceae (Gramineae). J Syst Evol 53:117137
Srikanth, A, Schmid, M (2011) Regulation of flowering time: All roads lead to Rome. Cell Mol Life Sci 68:20132037
Strofer, A, Murphy, MA, Evans, JS, Golberg, CS, Robinson, S, Spear, SF, Dezzani, R, Delmelle, E, Vierling, L, Waits, LP (2007) Putting the “landscape” in landscape genetics. Heredity 98:128142
Szucs, P, Skinner, JS, Karsai, I, Cuesta-Marcos, A, Haggard, KG, Corey, AE, Chen, THH, Hayes, PM (2007) Validation of the VRN-H2/VRN-H1 epistatic model in barley reveals that intron length variation in VRN-H1 may account for a continuum of vernalization sensitivity. Mol Genet Genomics 277:249261
Takahashi, R, Yasuda, S (1971) Genetics of earliness and growth habit in barley. Pages 388408 in Nilan RA, ed. Proceedings of the Second International Barley Genetics Symposium. Pullman, WA: Washington State University Press
Thill, DC, Beck, KG, Callihan, RH (1984) The biology of downy brome (Bromus tectorum). Weed Sci 32(Suppl 1):712
Trevaskis, B, Hemming, MN, Peacock, WJ, Dennis, ES (2006) HvVRN2 responds to daylength, whereas HvVRN1 is regulated by vernalization and developmental status. Plant Physiol 140:13971405
Yan, L, Fu, D, Li, C, Blechl, A, Tranquilli, G, Bonafede, M, Sanchez, A, Valarik, M, Yasuda, S, Dubcovsky, J (2006) The wheat and barley vernalization gene VRN3 is an ortholog of FT . Proc Natl Acad Sci USA 103:1958119586
Yan, L, Loukoianov, A, Tranquilli, G, Helguera, M, Fahima, T, Dubcovsky, J (2003) Positional cloning of the wheat vernalization gene VRN1 . Proc Natl Acad Sci USA 100:62636268
Von Zitzewitz, J, Szucs, P, Dubcovsky, J, Yan, L, Francia, E, Pecchioni, N, Casas, A, Chen, THH, Hayes, PM, Skinner, JS (2005) Molecular and structural characterization of barley vernalization genes. Plant Mol Biol 59: 449467



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