Effects of phenidone on insect elicitor- and Z -3-hexenyl acetate-induced jasmonic acid accumulation. Maize seedlings were treated overnight with phenidone and then induced by treatment with insect elicitor (IE) or exposure to Z-3-hexenyl acetate (Z-3-HAC). Jasmonic acid was measured 60 min after IE treatment and 30 min after Z-3-HAC exposure. A. Effect of phenidone on IE- induced jasmonic acid. Jasmonic acid was measured in the local (directly treated) and the distal section of the same leaf. B, C. Effect of phenidone on Z-3-HAC-induced jasmonic acid. B. Overnight treatment with phenidone had no effect on Z-3-HAC-induced JA accumulation when compared to similarly treated control plans. C. Maize seedling were first exposed to Z-3-HAC for 30 min and then treated with phenidone overnight. Controls were not exposed to Z-3-HAC, but also treated with phenidone overnight. After 15 h treatment with phenidone both treatment groups were exposed to Z-3-HAC. A significant reduction of jasmonic acid accumulation was found only in maize seedlings that were exposed to Z-3-HAC before phenidone treatment. Error bars represent standard deviation. An * indicates a significant difference between phenidone-treated and their respective control plant (t-test, p ≤ 0.05).