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

<p>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 <i>VSP2</i>, the content of total glucosinolates and the level of the reactive oxygen species in mature <i>Arabidopsis thaliana</i> plants after transferred into the stress-free environment. The previously primed plants could effectively resist the feeding of <i>Spodoptera litura</i> (Fabricius) larvae. Salt-priming enhanced defense of Arabidopsis plants in the absence of either <i>MYC2</i> or <i>AOS</i>, 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.</p>