Table 1.

Expression stability values for annual ryegrass candidate reference genes calculated using BestKeeper.

Rank	Acidic Aluminum Stress	Drought Stress	Heavy Metal Stress	Saline-Alkali Stress	All Samples
1	Unigene71	Unigene14912	Unigene71	Unigene14912	Unigene14912
	(1.48 ± 0.49)	(1.75 ± 0.58)	(0.86 ± 0.29)	(2.43 ± 0.82)	(2.14 ± 0.72)
2	eIF4A	Unigene71	HIS3	HIS3	Unigene755
	(1.76 ± 0.43)	(1.98 ± 0.71)	(1.56 ± 0.43)	(2.46 ± 0.71)	(2.95 ± 0.93)
3	Unigene14912	eIF4A	Unigene755	Unigene71	HIS3
	(1.9 ± 0.64)	(2.29 ± 0.55)	(1.56 ± 0.49)	(2.59 ± 0.93)	(3.08 ± 0.87)
4	HIS3	E2	E2	SAMDC	eIF4A
	(2.01 ± 0.56)	(2.68 ± 0.61)	(2.09 ± 0.47)	(2.78 ± 0.78)	(3.35 ± 0.83)
5	SAMDC	TBP-1	Unigene14912	TBP-1	Unigene77
	(2.41 ± 0.71)	(3.02 ± 0.72)	(2.26 ± 0.77)	(3.45 ± 0.86)	(3.4 ± 1.06)
6	Unigene755	SAMDC	Unigene77	Unigene755	Unigene71
	(2.51 ± 0.79)	(3.27 ± 0.87)	(2.3 ± 0.71)	(3.59 ± 1.13)	(3.69 ± 1.27)
7	Unigene77	HIS3	TBP-1	Unigene77	TBP-1
	(2.63 ± 0.80)	(4.14 ± 1.19)	(2.44 ± 0.57)	(3.96 ± 1.25)	(4.39 ± 1.06)
8	18S rRNA	Unigene755	eIF4A	eIF4A	E2
	(6.46 ± 0.84)	(4.14 ± 1.30)	(2.62 ± 0.65)	(4.11 ± 1.06)	(5.2 ± 1.21)
9	TBP-1	Unigene77	SAMDC	E2	SAMDC
	(8.25 ± 2.03)	(4.23 ± 1.32)	(3.78 ± 1.15)	(5.15 ± 1.25)	(5.22 ± 1.50)
10	E2	18S rRNA	18S rRNA	18S rRNA	18S rRNA
	(8.83 ± 2.06)	(8.82 ± 1.17)	(5.09 ± 0.67)	(9.7 ± 1.46)	(8.57 ± 1.17)
11	GAPDH	GAPDH	GAPDH	GAPDH	GAPDH
	(14.04 ± 3.44)	(11.84 ± 2.90)	(14.26 ± 3.31)	(12.12 ± 2.82)	(13.36 ± 3.19)

Note: expression stability and ranking of 11 candidate reference genes calculated with BestKeeper under all sample conditions, acidic aluminum, drought, heavy metal, and saline-alkali stress. The stability of eleven reference genes was identified based on the coefficient of variation (CV) and standard deviation (SD).