Ethylene signaling plays a pivotal role in mechanical-stress-induced root-growth cessation in Arabidopsis thaliana

ABSTRACT

Plant roots show growth cessation as a primary response to mechanical stress. To clarify the molecular basis of this response, we have previously established an assay system to monitor the root growth response of Arabidopsis seedlings to mechanical stimuli using dialysis membrane-covered agar media. Here we examined the effect of plant hormones and their related molecules on this response. Amino-cyclopropane carboxylate, a precursor of ethylene, remarkably enhanced the growth reduction while silver ions, which block ethylene perception, nullified the response. Furthermore, salicylic acid, which inhibits ethylene biosynthesis, alleviated the root growth reduction, whereas methyl jasmonate had no apparent effect on the response. These results suggest that the root-growth cessation observed in response to mechanical stress involves ethylene signaling; however, this response may be independent from the pathway that integrates signals from ethylene and jasmonate.

KEYWORDS:

• Arabidopsis
• ethylene
• mechanical stress
• root

Disclosure of potential conflicts of interest

The authors declare no potential conflicts of interest.

Additional information

Funding

This study was supported in part by a grant from the Nakahara Research and Education Foundation to TO and by Grants-in-Aid for Scientific Research [No. 19K06724] from the Japan Society for the Promotion of Science to TT.