Table 1. Information on the selected reference genes.

Gene name	Gene description	Gene IDa	Arabidopsis homolog locusb	E-value	Forward primer seqence 5′–3′	Reverse primer seqence 5′–3′	Productsize (bp)	Amplificationefficiency(%)	R2
ClACT	β-Actin	Cla007792	AT3G18780	0	F:CCATGTATGTTGCCATCCAG	R:GGATAGCATGGGGTAGAGCA	140	103.9	0.989
ClCAC	Clathrin adaptor complex subunit	Cla020794	AT4G24550	5e-50	F:AATTGTGGTTGATGCTGCAC	R:TGACAGCTGTACCTGGCATC	94	97.2	0.992
ClEF1α	Elongation factor 1-α	Cla010539	AT5G60390	0	F: AGCACGCTCTTCTTGCTTTC	R:ACGATTTCGTCGTACCTTGC	115	96.4	0.996
ClGAPDH	Glyceraldehy-3-phosphate-dehydrogenase	Cla013454	AT1G16300	2e-80	F:CTGGCAGTACTTTGCCAACA	R:AGGATTGGAGAGGAGGTCGT	87	92.3	0.991
ClIDH	NADP-isocitrate dehydrogenase	Cla009135	AT1G65930	2e-71	F:TGGCCTCTTTACCTAAGCACA	R:ATATGCCAGCAGCCTCAAAC	124	94.0	0.991
ClLUG	Leunig	Cla022288	AT4G32551	3e-62	F:TTGCTGGTCATTGGATGCTA	R:GCCGAAGCAACTAGACCTGA	138	103.3	0.995
ClPP2A	Protein phosphatase 2Aregulatory subunit A	Cla021905	AT1G69960	e-125	F:AAGAGCCCACCAGCTTGTAA	R:TGTTCTCCCCAATCTCAAGG	136	101.0	0.996
ClPTB	Polypyrimidine tract-binding protein 1	Cla004906	AT3G01150	2e-15	F:GGAGCAAACAGAAATCAAGC	R:AGCAGGCTCAGAGGAAGATG	133	107.9	0.992
ClRPS2	Ribosomal protein S	Cla021565	AT1G04270	3e-67	F:TGGCACTGATCAAGAAGCTG	R:TGATCATATTGCGGAGGTGA	97	98.4	0.996
ClSAND	SAND family protein	Cla001870	AT2G28390	4e-42	F:CAATTAGCAGCCGTCAACAA	R:GTTTTGTGAGGGCCAATTTC	100	109.6	0.996
ClTUA	α-Tubulin	Cla003129	AT1G64740	e-120	F:CTTGCTGGGAGCTCTATTGC	R:AACGGATTAAAAGCGTCGTG	105	94.6	0.992
ClUBC2	Ubiquitin-conjugating enzyme E2	Cla010164	AT2G02760	2e-81	F:CCAAATAAGCCACCGACAGT	R:TCATAGATTGGGCTCCATTG	118	93.7	0.991
ClUBCP	Ubiquitin carrier protein	Cla010163	AT1G14400	6e-81	F:ACCAACAGTCCGCTTTGTGT	R:ATTGGGCTCCACTGATTTTG	101	96.6	0.995
ClYLS8	Yellow-leaf-specific proein8	Cla020175	AT5G08290	e-78	F:AGAACGGCTTGTGGTCATTC	R:GAGGCCAACACTTCATCCAT	83	94.4	0.995
Cl18SrRNA c	18S ribosomal RNA				F:AGCCTGAGAAACGGCTACCACATC	R:ACCAGACTCGAAGAGCCCGGTAT		92.1	0.995

^aWatermelon gene ID in Cucurbit Genomics Database (http://www.icugi.org);

^bArabidopsis gene ID in TAIR database (http://www.arabidopsis.org/);

^cThe primer pair of 18SrRNA previously published was used here (Guo et al. 2011).