AUTHOR=González-Fontes Agustín , Herrera-Rodríguez M. B. , Martín-Rejano Esperanza M. , Navarro-Gochicoa M. T. , Rexach Jesús , Camacho-Cristóbal Juan J. TITLE=Root Responses to Boron Deficiency Mediated by Ethylene JOURNAL=Frontiers in Plant Science VOLUME=6 YEAR=2016 URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2015.01103 DOI=10.3389/fpls.2015.01103 ISSN=1664-462X ABSTRACT=

Low boron (B) supply alters the architecture of the root system in Arabidopsis thaliana seedlings, leading to a reduction in the primary root growth and an increase in the length and number of root hairs. At short-term (hours), B deficiency causes a decrease in the cell elongation of the primary root, resulting in a lower growth. Experimental approaches using ethylene insensitive Arabidopsis mutants, inhibitors of ethylene response, and GUS reporter lines suggest that ethylene is involved in these responses of the primary root to B deficiency. Furthermore, it has been shown that auxin participates in the inhibition of cell elongation under short-term B deprivation. These results support that an interaction between ethylene and auxin plays an important role in controlling the primary root elongation, in which a number of genes related to the synthesis, transport, and signaling of both phytohormones could modulate this effect. Evidence for a root cross-talk among both hormones and other possible intermediates (abscisic acid, calcium sensors, and reactive oxygen species) in response to B deficiency is provided and discussed.