Evaluation of qPCR reference genes in two genotypes of Populus for use in photoperiod and low-temperature studies

Table 4 Comparison of stability rankings between geNorm ^PLUS and BestKeeper

Populus trichocarpa
Shoot tips/buds		Young leaves		Mature leaves		Bark
geNorm^PLUS	BestKeeper	geNorm^PLUS	BestKeeper	geNorm^PLUS	BestKeeper	geNorm^PLUS	BestKeeper
CDC2*	UBQ7	PT1*	CDC2	TIP4-like*	18S rRNA	CDC2*	CDC2
PT1*	18S rRNA	TIP4-like*	ANT	CYC063*	ACT2	ACT2*	PT1
ACT2	CDC2	CDC2*	ACT2	PT1	CDC2	PT1	ACT2
UBQ7	PT1	ACT2	18S rRNA	UBQ7	ANT	UBQ7	UBQ7
TIP4-like	ACT2	UBQ7	PT1	CDC2	UBQ7	CYC063	ANT
CYC063	CYC063	18S rRNA	UBQ7	ACT2	PT1	TIP4-like	CYC063
18S rRNA	ANT	CYC063	TIP4-like	18S rRNA	TIP4-like	ANT	TIP4-like
ANT	TIP4-like	ANT	CYC063	ANT	CYC063	18S rRNA	18S rRNA
*Populus tremula x Populus alba*
Shoot tips/buds		Young leaves		Mature leaves		Bark
geNorm^PLUS	BestKeeper	geNorm^PLUS	BestKeeper	geNorm^PLUS	BestKeeper	geNorm^PLUS	BestKeeper
PT1*	CDC2	PT1*	CDC2	PT1*	ACT2	CYC063*	PT1
TIP4-like*	ACT2	TIP4-like*	ANT	TIP4-like*	18S rRNA	TIP4-like*	CDC2
UBQ7	ANT	UBQ7	18S rRNA	UBQ7	ANT	UBQ7	ANT
CDC2	18S rRNA	CDC2	ACT2	CYC063	CDC2	PT1	ACT2
ACT2	UBQ7	ACT2	PT1	CDC2	CYC063	CDC2	CYC063
CYC063	PT1	18S rRNA	TIP4-like	ACT2	UBQ7	ACT2	UBQ7
18S rRNA	TIP4-like	CYC063	UBQ7	18S rRNA	TIP4-like	18S rRNA	TIP4-like
ANT	CYC063	ANT	CYC063	ANT	PT1	ANT	18S rRNA

Candidate reference genes ordered from most stable (top) to least stable (bottom) for each tissue by geNorm^PLUS and BestKeeper in P. trichocarpa and P. tremula x P. alba. Reference genes indentified by geNorm^PLUS for inclusion in normalization calculations are indicated by * symbol.

ISSN: 1756-0500