Ford_2010_Proc.Natl.Acad.Sci.U.S.A_107_17527

Reference

Title : Neonicotinoid insecticides induce salicylate-associated plant defense responses - Ford_2010_Proc.Natl.Acad.Sci.U.S.A_107_17527
Author(s) : Ford KA , Casida JE , Chandran D , Gulevich AG , Okrent RA , Durkin KA , Sarpong R , Bunnelle EM , Wildermuth MC
Ref : Proc Natl Acad Sci U S A , 107 :17527 , 2010
Abstract :

Neonicotinoid insecticides control crop pests based on their action as agonists at the insect nicotinic acetylcholine receptor, which accepts chloropyridinyl- and chlorothiazolyl-analogs almost equally well. In some cases, these compounds have also been reported to enhance plant vigor and (a)biotic stress tolerance, independent of their insecticidal function. However, this mode of action has not been defined. Using Arabidopsis thaliana, we show that the neonicotinoid compounds, imidacloprid (IMI) and clothianidin (CLO), via their 6-chloropyridinyl-3-carboxylic acid and 2-chlorothiazolyl-5-carboxylic acid metabolites, respectively, induce salicylic acid (SA)-associated plant responses. SA is a phytohormone best known for its role in plant defense against pathogens and as an inducer of systemic acquired resistance; however, it can also modulate abiotic stress responses. These neonicotinoids effect a similar global transcriptional response to that of SA, including genes involved in (a)biotic stress response. Furthermore, similar to SA, IMI and CLO induce systemic acquired resistance, resulting in reduced growth of a powdery mildew pathogen. The action of CLO induces the endogenous synthesis of SA via the SA biosynthetic enzyme ICS1, with ICS1 required for CLO-induced accumulation of SA, expression of the SA marker PR1, and fully enhanced resistance to powdery mildew. In contrast, the action of IMI does not induce endogenous synthesis of SA. Instead, IMI is further bioactivated to 6-chloro-2-hydroxypyridinyl-3-carboxylic acid, which is shown here to be a potent inducer of PR1 and inhibitor of SA-sensitive enzymes. Thus, via different mechanisms, these chloropyridinyl- and chlorothiazolyl-neonicotinoids induce SA responses associated with enhanced stress tolerance.

PubMedSearch : Ford_2010_Proc.Natl.Acad.Sci.U.S.A_107_17527
PubMedID: 20876120

Related information

Citations formats

Ford KA, Casida JE, Chandran D, Gulevich AG, Okrent RA, Durkin KA, Sarpong R, Bunnelle EM, Wildermuth MC (2010)
Neonicotinoid insecticides induce salicylate-associated plant defense responses
Proc Natl Acad Sci U S A 107 :17527

Ford KA, Casida JE, Chandran D, Gulevich AG, Okrent RA, Durkin KA, Sarpong R, Bunnelle EM, Wildermuth MC (2010)
Proc Natl Acad Sci U S A 107 :17527