GLS, KRR, and sinapoyl malate (SM) production after 4 d of P. brassicae caterpillar feeding on previously unexposed (U), caterpillar-exposed (C), and aphid-exposed (A) wild-type (WT) and wrky70 plants. A and B, Means ± se (n = 5) levels of total and aliphatic GLSs in unexposed, caterpillar-exposed, and aphid-exposed wild-type and wrky70 plants. GLS was determined by HPLC using the peak areas at 229 nm relative to the peak area of the internal standard. C and D, Means ± se (n = 5) of KRR (C) and SM (D) in unexposed, caterpillar-exposed, and aphid-exposed wild-type and wrky70 mutant plants after 4 d of subsequent feeding by five first instar P. brassicae caterpillars. KRR levels were quantified by HPLC based on an external standard curve of an authentic standard of KRR. SM levels were determined by HPLC based on an external standard curve of an authentic standard of sinapic acid. GLS, KRR, and SM levels in unexposed, caterpillar-exposed, and aphid-exposed wild-type and wrky70 mutant plants were compared by one-way ANOVA followed by Tukey’s HSD posthoc test; different letters indicate significant differences (P ≤ 0.05) among treatments within the same genotype. DM, Dry mass.