Divergence time between 14 species was estimated using McMctree in PAML66 with the options ‘correlated molecular clock’ and ‘JC69’ model. A Markov Chain Monte Carlo analysis was run for 20,000 generations, using a burn-in of 1000 iterations. Five calibration points were applied in the present study (Fig. 1): P. equestris and D. officinale divergence time (47~52.9 million years ago) 67, O. sativa and Z. mays divergence time (24–84 million years ago)68,69, A. thaliana and P. trichocarpa divergence time (65–89 million years ago) 70,71, P. trichocarpa and G. max divergence time (56–89 million years ago)56,57, and, root of land plants (407–557 million years ago) 57.