Trizol based

Total RNA was extracted from maize root tissues using a TRIzol based method (Invitrogen). qRT-PCR was carried out as previously described (Tanaka et al., 2011 (link)). All data were normalized to a reference gene, folylpolyglutamate synthase (FPGS; GRMZM2G393334), which is one of the most reliable reference genes for qRT-PCR for maize (Manoli et al., 2012 (link)). Using Ct value (cycle threshold), gene expression levels relative to the reference gene FPGS were calculated for each sample as 2−ΔCt= [2−(Ct sample)]/[2−(Ct FPGS)]. The values of three replicates were used in a Student’s t test to calculate probabilities of distinct induction or repression, and the average ratio of these values to control treatment was used as 2^-ΔΔCt to determine the fold change in transcript level (i.e. LCO treatment vs. mock treatment). Primers used are listed in Supplementary Table S5.

Total RNA was extracted by the standard Trizol-based protocol (Invitrogen, USA). Complementary DNA (cDNA) was synthesized using the PrimeScript RT Reagent Kit (Invitrogen, USA) and SYBR Premix Ex Taq (TaKaRa Bio, Shiga, Japan) was employed in qRT-PCR, according to the manufacturer's instructions. Supplementary Table 1 has shown the information of gene-specific primers.