Egg extract-induced SA/JA cross talk is abolished in npr1-1 ein2-1 mutant. A, Experimental scheme used with 12-d-old seedlings. One microliter of egg extract (EE) was applied underneath the first true leaf. After 24 h, the leaf was wounded twice with forceps and harvested after 3 h (EE + W). Controls consisted of untreated plants (C), plants only treated with egg extract (EE), or plants only wounded (W). B and C, Expression of VSP2 and PDF1.2 was measured by real-time PCR. Twelve-day-old seedlings were subjected to the treatments described in A. Values ± se are the mean of three biological replicates and normalized to the reference gene SAND. Different letters within each genotype indicate significant differences at P < 0.05 (Tukey’s highly significant difference test). D, Freshly hatched S. littoralis larvae were placed on 4-week-old Col-0 or npr1-1 ein2-1 plants, and larval weight was measured after 10 d of feeding. White bars indicate untreated control plants challenged with insects (C). Black bars indicate plants treated with egg extract (EE) for 5 d before insect challenge. The number of larvae used in each experiment is shown within the bars. Error bars indicate se. Significant differences between control and treated plants are indicated (Student’s t test; ***P < 0.001; n.s., not significant). This experiment was repeated twice with similar results.