Sodium chloride primes JA-independent defense against Spodoptera litura (Fabricius) larvae in Arabidopsis thaliana

ABSTRACT

Priming for better defense performance is an important strategy in acclimation to the ever-changing environment. In the present study, defense priming induced by sodium chloride at the seedling stage significantly increased the expression of defense gene VSP2, the content of total glucosinolates and the level of the reactive oxygen species in mature Arabidopsis thaliana plants after transferred into the stress-free environment. The previously primed plants could effectively resist the feeding of Spodoptera litura (Fabricius) larvae. Salt-priming enhanced defense of Arabidopsis plants in the absence of either MYC2 or AOS, which encodes a critical transcription factor in JA-signaling and an important enzyme in JA biosynthesis, respectively. Our results supported the JA-independent defense primed by sodium chloride, as well as the elevated ROS and glucosinolate level in primed plants. In addition, the feasibility of using mild salt-priming to improve crop performance in field was proposed.

KEYWORDS:

• Sodium chloride
• defense priming
• herbivory
• jasmonic acid pathway
• Arabidopsis thaliana

Disclosure statement

No potential conflicts of interest were disclosed.

Author’s contributions

Mu Xiao conducted the experiments of seedling priming, bioassay, RT-qPCR, secondary metabolite measurements and data processing. Rong Liu was responsible for rearing the insects and verifying knock-out of MYC2. Ying Ruan and Chunlin Lin designed the experiments and drafted the manuscript. All authors participated in the manuscript revision.

Supplementary material

Supplemental data for this article can be accessed on the publisher’s website.

Additional information

Funding

This work was supported by the National Center for Research and Development [grant number 2016YFD0100202] and Education Department of Hunan Province [grant number 17A101], [grant number 17K045].