Editing Root nodule (section)

== Connection to root structure ==
Root nodules apparently have evolved three times within the [[Fabaceae]] but are rare outside that family. The propensity of these plants to develop root nodules seems to relate to their root structure. In particular, a tendency to develop lateral roots in response to [[abscisic acid]] may enable the later evolution of root nodules.<ref>{{Cite journal |last1=Liang |first1=Yan |last2=Harris |first2=Jeanne M. |date=2005 |title=Response of root branching to abscisic acid is correlated with nodule formation both in legumes and nonlegumes |url=https://bsapubs.onlinelibrary.wiley.com/doi/10.3732/ajb.92.10.1675 |journal=American Journal of Botany |language=en |volume=92 |issue=10 |pages=1675–1683 |doi=10.3732/ajb.92.10.1675 |issn=0002-9122 |pmid=21646084|url-access=subscription }}</ref>