Plant Materials and Growth Conditions
The B. napus cultivar ‘Westar 10’ curated in our laboratory was
used for phenotypic analyses and mRNA expression profiling. Seeds were
surface-sterilized for 12 minutes using 1% NaClO and washed five times
with pure water. Then, the seeds were germinated on a piece of gauze
moistened with pure water. After 7 days, uniformly sized seedlings were
transferred to one-half strength Hoagland nutrient solution refreshed
every four days. The normal concentration of
KH2PO4 in Hoagland nutrient solution
(Hoagland and Arnon, 1950) was 100 µM unless otherwise stated. Plants
were cultivated in a growth room at 22℃ with a 16-h-light/8-h-dark
photoperiod (with a photon flux density of 300-320 lmol
m-2 s-1). Arabidopsis seedings were
grown for one week on solid 1/2 MS (Murashige and Skoog) medium
(Murashige and Skoog, 1962) then transferred to ANS (Arabidopsis
nutrition solution) (Liu et al., 2016). For pot experiment, 7 kg soil/
pot was soaked 2,000 ml water including 3.005 g KNO3,
1.75 g MgSO4·7H2O, 4.643 g
(NH4)2SO4 and 7 ml Arnon
storage solution (1,000 ×), 7 ml FeSO4·EDTA Hogland
storage solution (200 ×), 755.5 mg/kg or 2,518.3 mg/kg
NaH2PO4·2H2O.