Table 2.

Sequences of primers used in reverse–transcription quantitative PCR (RT–qPCR) and functional annotation of six candidate genes.

Gene ID (Encoded Protein)	Gene Position	Primer Sequence (5′ to 3′)	Gene Functional Annotation
GRMZM2G396553 (Arginine decarboxylase 1, ADC1)	Chromosome 9 (23396672_23399720 bp)	F: GCTACGGCTCAAGGTACCAG R: CCGAACTCCACAATGTCCTC	Arginine decarboxylase activity (GO:0008792); Arginine catabolic process (GO:0006527); Response to cold (GO:0009409)
GRMZM2G120578 (Spermidine synthase 1, SPDS1)	Chromosome 5 (72695353_72701535 bp)	F: TGTTCAATTCCATCCCCTAAA R: TCCACTGAACTGTGTCTGGAA	Catalytic activity (GO:0003824); Transferase activity (GO:0016740); Polyamine metabolic process (GO:0006595); Polyamine biosynthetic process (GO:0006596)
GRMZM2G396856 (Probable polyamine oxidase 2, PAO2)	Chromosome 10 (143652563_143657803 bp)	F: CACACACACCATCCGCTATT R: CATCAGCAGCAGCAAGACC	Oxidoreductase activity (GO:0016491); Polyamine oxidase activity (GO:0046592); Polyamine catabolic process (GO:0006598)
GRMZM2G059991 (Superoxide dismutase 3, SOD3)	Chromosome 6 (140001982_140006117 bp)	F: TCACCCAAGAGGGAGATG R: TTGCTCGCAGGATTGTAG	Removal of superoxide radicals (GO:0019430); Superoxide dismutase activity (GO:0004784); Oxidoreductase activity (GO:0016491)
GRMZM2G089982 (Peroxidase 72, POD72)	Chromosome 3 (40090724_40092823 bp)	F: GGATGTATCCTACGCCGCAA R: TTGTCAAACTTGGCAGGGGT	Peroxidase activity (GO:0004601); Oxidoreductase activity (GO:0016491); Response to oxidative stress (GO:0006979)
GRMZM2G088212 (Catalase 1, CAT1)	Chromosome 5 (65456774_65461269 bp)	F: CCGAATCCAAAGACCAAT R: ATGCCAACATCGTCAAAGAG	Catalase activity (GO:0004096); Peroxidase activity (GO:0004601); Response to oxidative stress (GO:0006979); Response to heat (GO:0009408)
GRMZM2G126010 (actin 1)	Chromosome 8 (102413768_102417536 bp)	F: CGATTGAGCATGGCATTGTCA R: CCCACTAGCGTACAACGAA	ATP binding (GO:0005524); Nucleotide binding (GO:0000166)