Funding for this research was provided by:
Biotechnology and Biological Sciences Research Council (BB/N005104/1, BB/L011786/1)
Received: 28 June 2017
Accepted: 3 April 2018
First Online: 13 April 2018
Ethics approval and consent to participate
: All plants used in this study were grown in controlled growth chambers complying with University of Liverpool guidelines. Plant material was supplied from the Germplasm Resources Unit at the John Innes Centre, Norwich, UK.
: The authors declare that they have no competing interests.
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