 coding regions (see [Supplementary Fig. S0](http://jxb.oxfordjournals.org/lookup/suppl/doi:00.0000/jxb/ert000/-/DC0) and [Supplementary Table S0](http://jxb.oxfordjournals.org/lookup/suppl/doi:00.0000/jxb/ert000/-/DC0) at *JXB* online).  