Euphytica

, Volume 168, Issue 3, pp 403–411 | Cite as

Late maturity α-amylase in synthetic hexaploid wheat

  • Kolumbina Mrva
  • Judy Cheong
  • Bo Yu
  • Hai Yunn Law
  • Daryl Mares
Article

Abstract

Late maturity α-amylase (LMA) is a genetic defect that is fairly widely spread in bread wheat (Triticum aestivum L.) germplasm, and recently detected in durum cultivars, which can result in unacceptably high α-amylase activity (low falling number) in ripe grain. LMA has also been observed at unexpectedly high frequency and severity in synthetic hexaploid wheats derived from the interspecific hybridisation of Triticum durum (AABB) and Aegilops tauschii (DD). Since synthetic hexaploids represent an important new source of resistances/tolerances to a range of biotic and abiotic stresses for wheat breeders, there is a pressing need to understand the mechanisms involved in LMA in synthetics and develop strategies for avoiding its adverse effects on grain quality. The objectives of this study were to firstly, compare the LMA phenotype of synthetics that varied for plant height, secondly, to characterise the LMA phenotype in groups of synthetics derived from the same durum parents and finally to determine whether LMA in primary synthetics is associated with the QTL previously reported in conventional bread wheat. More than 250 synthetic hexaploids, a range of durum cultivars and a doubled haploid population derived from Worrakatta (non-LMA) × AUS29663 (high LMA synthetic) were phenotyped and genotyped with markers reported to be linked to LMA in conventional bread wheat and markers diagnostic for the semi-dwarfing gene, Rht1. More than 85% of synthetics were prone to LMA, approximately 60% ranked as very high. Genetic control of LMA in synthetic hexaploids appeared to involve QTL located on 7B, and to a lesser extent 3B, similar to bread wheats. However, the LMA phenotype of many synthetic hexaploids appeared to be more extreme than could be explained by comparisons with bread wheat even taking into account the apparent absence of Rht1 in most genotypes. Other mechanisms, possibly triggered by the interaction between the AABB and DD genomes cannot be excluded. The presence of wild type rht1 in most synthetic hexaploids and their extreme height is difficult to reconcile with the semi-dwarf, Rht1, stature of many of the durums used in the interspecific hybridisation process. Mechanisms that could explain this observation remain unclear.

Keywords

High α-amylase Semi-dwarfing gene (Rht1Molecular markers 

Abbreviations

LMA

Late maturity α-amylase

QTL

Quantitative trait locus

References

  1. Ellis MH, Spielmeyer W, Gale KR, Rebetzke GJ, Richards RA (2002) “Perfect” markers for Rht-B1b and Rht-D1b dwarfing genes in wheat. Theor Appl Genet 105:1038–1042PubMedCrossRefGoogle Scholar
  2. He P, Friebe BR, Gill BS, Zhou J-M (2003) Alloploidy alters gene expression in a highly stable hexaploid wheat. Plant Mol Biol 52:401–414PubMedCrossRefGoogle Scholar
  3. Kashkush K, Feldman M, Levy AA (2002) Gene loss, silencing and activation in a newly synthesized wheat allotetraploid. Genetics 160:1651–1659PubMedGoogle Scholar
  4. Mares DJ, Mrva K (2008a) Late-maturity α-amylase: low falling number in wheat in the absence of preharvest sprouting. J Cereal Sci 47:6–17CrossRefGoogle Scholar
  5. Mares DJ, Mrva K (2008b) Genetic variation for quality traits in synthetic wheat germplasm. Aust J Agric Res 59(5):406–412CrossRefGoogle Scholar
  6. Mrva K, Mares DJ (1996) Expression of late maturity α-amylase in wheat containing gibberellic acid insensitivity genes. Euphytica 88:68–76Google Scholar
  7. Mrva K, Mares DJ (2001a) Quantitative trait locus analysis of late maturity α-amylase in wheat using the doubled haploid population Cranbrook × Halberd. Aust J Agric Res 52:1267–1273CrossRefGoogle Scholar
  8. Mrva K, Mares DJ (2001b) Induction of late maturity α-amylase in wheat by cool temperature. Aust J Agric Res 52:477–484CrossRefGoogle Scholar
  9. Mujeeb-Kazi A, Rosas V, Roldan S (1996) Conservation of the genetic variation of Triticum tauschii (Coss.) Schmalh. (Aegilops squarrosa auct. non L.) in synthetic hexaploid wheats (T. turgidum L. s.lat, × T. tauschii; 2n = 6x = 42, AABBDD) and its potential utilization for wheat improvement. Genet Res Crop Evol 43:129–134CrossRefGoogle Scholar
  10. Nelson JC, Sorrells ME, Van Deynze AE, Lu YH, Atkinson M, Bernard M, Leroy P, Faris JD, Anderson JA (1995) Molecular mapping of wheat: major genes and rearrangements in homoeologous groups 4, 5, and 7. Genetics 141:721–731PubMedGoogle Scholar
  11. Röder MS, Korzun V, Wendehake K, Plaschke J, Tixier M-H, Leroy P, Ganal MW (1998) A microsatellite map of wheat. Genetics 149:2007–2023PubMedGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Kolumbina Mrva
    • 1
  • Judy Cheong
    • 2
  • Bo Yu
    • 1
  • Hai Yunn Law
    • 1
  • Daryl Mares
    • 1
  1. 1.School of Agriculture, Food & WineUniversity of AdelaideGlen OsmondAustralia
  2. 2.SARDIAdelaideAustralia

Personalised recommendations