Table 4. Candidate reference genes for cold and heat stresses determined by GeNorm, NormFinder, BesteKeeper, and by the combination of the 3 algorithms.
| COLD | COLD | COLD | COLD | HEAT | HEAT | HEAT | HEAT | |
| Rank | GeNorm M | NormFinder SV | BestKeeper SD/r | Geometric Mean | GeNorm M | NormFinder SV | BestKeeper SD/r | Geometric Mean |
| 1 | GAPDH | GSA (0.147) | TUB (0.104) | RBCL (0.10/0.213) | TUB (2.154) | 26S | H2A (0.174) | TUB (0.139) | 26S (0.28/0.798) | 26S (1.442) |
| 2 | 18S (0.121) | TUB (0.12/0.641) | GSA (2.714) | H2A (0.207) | H2A (0.34/0.826) | H2A (1.587) | ||
| 3 | 18S (0.166) | 26S (0.121) | 26S (0.12/0.704) | GAPDH (2.884) | GSA (0.336) | 26S (0.262) | 18S (0.35/0.494) | TUB (2.884) |
| 4 | 26S (0.179) | GAPDH (0.124) | GSA (0.16/0.697) | 26S (3.302) | SDR (0.425) | RBCL (0.338) | TUB (0.42/0.912) | 18S (4.932) |
| 5 | TUB (0.189) | GSA (0.152) | HYP1 (0.17/0.001) | 18S (3.476) | HYP1 (0.478) | 18S (0.473) | RBCL (0.54/0.760) | GSA (5.013) |
| 6 | SDR (0.199) | SDR (0.156) | GAPDH (0.17/0.705) | RBCL (3.826) | TUB (0.528) | GSA (0.561) | PKS1 (0.56/0.638) | RBCL (5.192) |
| 7 | H2A (0.208) | RBCL (0.169) | 18S (0.21/0.925) | SDR (6.604) | RBCL (0.584) | PKS1 (0.595) | GSA (0.57/0.634) | SDR (7.368) |
| 8 | RBCL (0.219) | H2A (0.240) | SDR (0.23/0.925) | HYP1 (7.399) | 18S (0.617) | GAPDH (0.648) | GAPDH (0.67/0.805) | HYP1 (7.399) |
| 9 | HYP1 (0.250) | HYP1 (0.339) | H2A (0.26/0.897) | H2A (7.958) | GAPDH (0.650) | HYP1 (0.716) | HYP1 (0.75/0.814) | PKS1 (7.489) |
| 10 | PKS2 (0.283) | PKS2 (0.384) | PKS2 (0.29/0.407) | PKS2 (10.00) | PKS1 (0.686) | SDR (0.764) | SDR (0.76/0.666) | GAPDH (8.320) |
| 11 | PKS1 (0.328) | PKS1 (0.486) | PKS1 (0.30/0.365) | PKS1 (11.00) | PKS2 (0.828) | PKS2 (1.416) | PKS2 (0.87/0.001) | PKS2 (11.00) |
M: expression stability average; SV: stability value; SD: standard deviation of Cq value; r: Pearson coefficient of correlation.