Pennycress seeds of the Ames 30982 accession were obtained from the North Central Regional Plant Introduction Station. The seeds were germinated on plates prior to transfer to pots (Supplementary Fig. S1 at JXB online). Briefly, the seeds were sterilized for 5min with 50% bleach in a 2ml tube and rinsed with sterile water a total of four times. Then, the seeds were placed between two aseptic Whatman papers in a 100×15mm glass Petri dish. Sterile Murashige and Skoog salt medium containing 1mM G4/G7 gibberellins, pH 6.0, was added and the plate was sealed with parafilm. Seeds were allowed to germinate for 3–5 d at 22 °C. Finally, the germinated kernels were transferred to pots (14 cm×14 cm×18cm), and grown in a growth chamber at 22 °C under a constant light intensity of 200 μmol m–2 s–1 and a 16h/8h day/night cycle. Upon emergence of the first pair of true leaves, the plants were transferred to a cold room (4 °C) for 3 weeks. The light intensity and day/night cycle were 100 μmol m–2 s–1 and 10h/14h, respectively. This step was crucial in ensuring that plants flowered later on. The plants were then placed back into their initial growth chamber and allowed to grow until maturity. The pennycress flowers were hand pollinated and tagged every day in order to study the embryo metabolism at different developmental stages.
Free full text: Click here
