Experiment 1: Maize suberin mutants (Zmasft)
Maize (Zea mays L.) seeds were planted in 11.3 L pots and placed
in a controlled-environment growth chamber (Biochambers, GRC-36,
Winnipeg, MB, Canada). The photoperiod was 16 h with a 1-hour ramp for
light reaching 1000 μmol quanta m-2s-1 at canopy level and 1-hour ramp for temperature to
mimic dawn and dusk. Day/night temperatures were set at 28°C/20°C,
respectively and relative humidity was kept at 70 %. The pots were
distributed in two light treatments even before germination: high light
(HL) exposed to 1200 μmol quanta m-2s-1 at canopy level and low light (LL) exposed to 300
μmol quanta m-2 s-1 at canopy level.
The plants were grown simultaneously in the same growth chamber and the
height of the pots was adjusted to maintain the desired light treatments
throughout the experiment.
Five replicates of each genotype were grown in a soil mixture of
Sunshine Mix LC-1 (Sun Gro Horticulture). Plants were watered daily and
fertilized every four days, initially with 20-20-20 and later with
15-5-15 CalMag. Experiment was conducted from March to May 2015, at
Washington State University, Pullman, WA, USA.