BioEnergy Research

, Volume 8, Issue 2, pp 857–867 | Cite as

Control of Vegetative to Reproductive Phase Transition Improves Biomass Yield and Simultaneously Reduces Lignin Content in Medicago truncatula

  • Million TadegeEmail author
  • Fang Chen
  • Jeremy Murray
  • Jiangqi Wen
  • Pascal Ratet
  • Michael K. Udvardi
  • Richard A. Dixon
  • Kirankumar S. MysoreEmail author


Lignocellulosic biomass has the potential to be a significant source of renewable energy, provided that current challenges regarding sufficient biomass production and efficient biomass conversion are met. Floral transition is a major developmental switch in the life of flowering plants which dictates whether photosynthetic products should be invested in vegetative growth or reproductive development. To directly evaluate the contribution of floral transition to biomass yield, we manipulated the onset of flowering in the model legume Medicago truncatula using a mutagenesis approach. Through forward genetics screening of Tnt1-tagged mutants, we identified three M. truncatula lines altered in flowering time and fertility: a delayed flowering mutant named vernalization-insensitive delayed flowering in long days (vdf), a nonflowering stemless mutant named headless (hdl), and a male sterile mutant named medicago male sterile 1 (mms1). Biomass yield analyses at different stages of development in these mutants revealed that the vdf mutant had the highest aboveground biomass and the hdl mutant had the lowest biomass at 70 days after germination. The difference in biomass yield between the vdf mutant and wild-type R108 became apparent after floral initiation and peaked at 90 days after germination, the late blooming stage for R108, where the vdf plants produced approximately twofold more biomass than R108. Interestingly, vdf, hdl, and mms1 mutants produced significantly less lignin than R108. Our results suggest that delaying floral initiation could be employed as a convenient tool to simultaneously improve biomass quantity and quality, provided that this is achieved without pleiotropic developmental defects.


Floral transition Biomass yield Lignin content Digestibility Feedstock Biofuel crops Medicago mutants 



This work was supported by the Samuel Roberts Noble Foundation and the National Science Foundation (EPSCoR Grant EPS-0814361). The insertion mutant lines of M. truncatula were created through research support, in part, from the National Science Foundation (DBI-0703285).


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Million Tadege
    • 1
    • 2
    Email author
  • Fang Chen
    • 3
  • Jeremy Murray
    • 4
  • Jiangqi Wen
    • 1
  • Pascal Ratet
    • 5
  • Michael K. Udvardi
    • 1
  • Richard A. Dixon
    • 3
  • Kirankumar S. Mysore
    • 1
    Email author
  1. 1.Plant Biology DivisionThe Samuel Roberts Noble FoundationArdmoreUSA
  2. 2.Department of Plant and Soil Sciences, Institute for Agricultural BiosciencesOklahoma State UniversityArdmoreUSA
  3. 3.Department of Biological SciencesUniversity of North TexasDentonUSA
  4. 4.John Innes CentreNorwichUK
  5. 5.Institut des Sciences du VégétalCentre National de la Recherche Scientifique, Saclay Plant SciencesGif sur Yvette CedexFrance

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