Transcript levels for select GA metabolism genes in Arabidopsis seedlings. The levels of transcript for KS, GA2ox2, GA3ox1, GA20ox1, GA20ox2, and GA20ox3 relative to ACT2 in ebf2-3 and ein3-1 eil1-1 mutants were normalized to levels in untreated Col seedlings. Seedlings were grown in the dark in air for 2 d, RNA was extracted, and the transcript was analyzed with qRT-PCR. Transcript levels in untreated seedlings (closed bars) were compared with seedlings treated with 1 µL L−1 ethylene for 2 h before RNA extraction (open bars). Data shows the average ± sem for three biological replicates with two to three technical replicates each. aStatistical difference compared with untreated Col (P ≤ 0.05); bstatistical difference caused by treatment with ethylene compared with untreated seedlings of that background (P ≤ 0.05); cstatistical difference caused by ethylene compared with ethylene-treated Col seedlings (P ≤ 0.05).