Exogenous Amino Acids Induce Systemic Blast resistance in Rice

Plant immune responses can be induced by endogenous and exogenous signaling molecules. Recently, amino acids and their metabolites have been reported to affect the plant immune system. However, how amino acids act in plant defense responses has yet to be clarified.

Naoki Kadotani and researchers from Ajinomoto Co. and the National Institute of Agrobiological Sciences in Japan recently studied how treatment of rice roots with amino acids such as glutamate (Glu) induced systemic disease resistance against rice blast in leaves.

Treatment of roots with Glu activated the transcription of a large variety of defense-related genes in roots as well as leaves. In the leaves, salicylic acid-responsive genes were induced by this treatment. The Glu-induced blast resistance was also found partially impaired in rice plants that lacks in SA signaling while jasmonic acid-deficient mutant cpm2 exhibited full Glu-induced blast resistance. These results indicate that the amino acid-induced blast resistance partly depends on the salicylic acid pathway.

For more on the study, read the article on BMC Plant Biology.