Shattering fruits: variations on a dehiscent theme

- Pod dehiscence is the seed dispersal mechanism for many species, including crops.
- Plant hormones play key roles, both as morphogenetic instructors and as triggers.
- The genetic network for dehiscence zone formation is highly conserved in dicots.
- Variation in pod lignification patterns drives evolutionary diversification.
- Understanding dehiscence zone formation may successfully impact on crop improvement.

Fruits are seed dispersal units, and for that they have evolved different strategies to facilitate separation and dispersal of the progeny from the mother plant. A great proportion of fruits from different clades are dry and dehiscent, opening upon maturity to disperse the seeds. In the last two decades, intense research mainly in Arabidopsis has uncovered the basic network that controls the differentiation of the Arabidopsis fruit dehiscence zone. This review focuses on recent discoveries that have helped to complete the picture, as well as the insights from evo-devo and crop domestication studies that show how the conservation/variation of the elements of this network across species accounts for its evolutionary plasticity and the origin of evolutionary innovations.