Reference Gene Selection for Quantitative Real-Time RT-PCR Normalization in Iris. lactea var. chinensis Roots under Cadmium, Lead, and Salt Stress Conditions

Table 3

Ranking of seven reference genes in order of their expression stability calculated by NormFinder.

Ranking order	Total		Cd		NaCl		Pb
	Gene	Stability	Gene	Stability	Gene	Stability	Gene	Stability
1	EIF-5A	0.295	EIF-5A	0.084	HIS	0.194	UBC	0.263
2	UBC	0.308	ACTIN	0.296	UBC	0.225	EIF-5A	0.332
3	EF1α	0.374	UBC	0.310	ACTIN	0.308	EF1b	0.364
4	EF1b	0.379	EF1α	0.366	EIF-5A	0.342	HIS	0.396
5	ACTIN	0.448	EF1b	0.367	TUBLIN	0.367	EF1α	0.446
6	HIS	0.450	HIS	0.442	EF1b	0.371	TUBLIN	0.599
7	TUBLIN	0.613	TUBLIN	0.480	EF1α	0.411	ACTIN	0.643