Fig. 2

Growth analysis of the etiolated mesocotyl. After imbibition for 12 h, the maize seeds were germinated in darkness at 25 °C for a week. a Growth curve of the mesocotyl in vivo. The arrows indicate the sampling time (48 h, 84 h and 132 h) for proteomic analysis. b IAA content change with mesocotyl growth. IAA was determined per fresh weight. c IAA content in different parts of mesocotyl. The mesocotyls were sampled from 84-h-old etiolated seedlings. IAA was determined per fresh weight. d Light microscopy of the mesocotyl, showing the changes in cell morphology at the apical 5 mm part with mesocotyl growth. Bar = 10 μm. e Light microscopy of the mesocotyls, showing the changes in cell morphology at different parts of the 84-h-old mesocotyls. Bar = 10 μm. f Mesocotyl growth in vivo for 48 h and in vitro for 12 h. The mesocotyls were marked to show the differential elongation of different parts. g IAA effect on mesocotyls grown in vitro for 12 h. ** denotes p < 0.01, ns stands for not significant. h Growth curve of the mesocotyl in vitro with or without 10 μM IAA. The mesocotyl segments were sampled from 84-h-old etiolated seedlings