Table 2. Candidate reference genes for Biotic Stress effect in V. vinifera cv Trincadeira calculated by the GeNorm, NormFinder and BestKeeper.

Candidate genes	Trincadeira
	GeNorm	NormFinder	BestKeeper
	M	SV	SD	r
SAND	0.881 (1/2)	0.727 (3)	0.92 (5)	0.74*
EF1α	0.881(1/2)	0.722 (2)	0.86 (3)	0.87*
SMD3	0.975 (3)	0.454 (1)	0.66 (1)	0.76*
ACT	1.038 (4)	0.849 (5)	0.92 (4)	0.75*
UBQ	1.088 (5)	1.231 (6)	1.00 (6)	0.58*
GAPDH	1.158 (6)	0.813 (4)	0.84 (2)	0.81*
60 S	1.305 (7)	1.511 (7)	1.09 (8)	0.25*
PsaB	1.470 (8)	1.799 (8)	1.41 (7)	0.74*

SV. stability value; SD, standard deviation of Cq value; r. Pearson coefficient of correlation; * p≤0.001. p-value associated with the Pearson coefficient of correlation. Ranking order is presented in parenthesis.