Transgenic Research

, Volume 17, Issue 4, pp 587–597 | Cite as

Development of an in planta method for transformation of alfalfa (Medicago sativa)

  • J Troy Weeks
  • Jingsong Ye
  • Caius M RommensEmail author
Original Paper


Conventional methods in transforming alfalfa (Medicago sativa) require multiple tissue culture manipulations that are time-consuming and expensive, while applicable only to a few highly regenerable genotypes. Here, we describe a simple in planta method that makes it possible to transform a commercial variety without employing selectable marker genes. Basically, young seedlings are cut at the apical node, cold-treated, and vigorously vortexed in an Agrobacterium suspension also containing sand. About 7% of treated seedlings produced progenies segregating for the T-DNA. The vortex-mediated seedling transformation method was applied to transform alfalfa with an all-native transfer DNA comprising a silencing construct for the caffeic acid o-methyltransferase (Comt) gene. Resulting intragenic plants accumulated reduced levels of the indigestible fiber component lignin that lowers forage quality. The absence of both selectable marker genes and other foreign genetic elements may expedite the governmental approval process for quality-enhanced alfalfa.


Marker-free transformation in planta transformation Intragenic alfalfa Biotechnology 



The authors are grateful to Scott Simplot, Bill Whitacre, and Dr. Kathy Swords for fruitful discussion and support. Serena McCoy, Jeff Hein, and Michele Krucker are acknowledged for excellent technical assistance.


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Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  1. 1.J. R. Simplot Company, Simplot Plant SciencesBoiseUSA

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