Jasmonic acid alleviates boron toxicity in Puccinellia tenuiflora, a promising species for boron phytoremediation

Abstract

Jasmonic acid (JA), a plant hormone and signal molecule, is known to enhance plant tolerance to various biotic and abiotic stresses. Our purpose is to determine the effect of JA on boron (B) toxicity in a B-tolerant species, Puccinellia tenuiflora, especially on seed germination and seedling growth. In a germination trial, we germinated P. tenuiflora seeds using Petri dishes under 300 mg L−1 B with JA treatment in the concentration range of 0.1–10 μM. In a hydroponic experiment, P. tenuiflora seedlings were grown under 250 mg L−1 B with JA treatment at a concentration of 0.1 and 1.0 mM, respectively. The germination trial shows that JA has an alleviatory effect on the inhibition of germination induced by excess B. The hydroponic experiment shows that JA is able to mitigate the inhibition of plant growth caused by excess B. The effect of JA was dose dependent, and only appropriate concentrations of JA were found to alleviate B toxicity in P. tenuiflora. Our findings suggest that the application of exogenous JA is able to help plants tolerate high levels of B at both the germination and seedling stages, which also indicates that JA is a promising growth regulator for P. tenuiflora under excess B.