Both logistic hormetic models equally suitable.

<p>Dose-response relationships for effects of different phytotoxins on root growth of <i>Amaranthus hybridus</i> (A), <i>Lactuca sativa</i> (B–F), or <i>Medicago sativa</i> (G) and for effects of root exudates of <i>Triticum aestivum</i> on root growth of <i>Sinapis alba</i> (H) and their description by the hormetic dose-response models after Brain and Cousens <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0033432#pone.0033432-Brain1" target="_blank">[9]</a> (grey curve) or Cedergreen et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0033432#pone.0033432-Cedergreen1" target="_blank">[2]</a> (black curve). Both models provided an adequate, marginally varying fit. Error bars represent standard deviation.