The resistance encountered by a seedling as it pushes through the soil causes inhibition of stem elongation and stimulates stem thickening, facilitating soil penetration. A new study demonstrates that two proteolytic pathways work in double-negative fashion - one targeting the other - to protect transcription factors central to this response.
Briggs, W. R. (2016, January 25). Plant Biology: Seedling Emergence through Soil. Current Biology. Cell Press. https://doi.org/10.1016/j.cub.2015.12.003