Objective To select the stable internal reference genes by real-time PCR (qRT-PCR) under different abiotic stress conditions in Clerodendrum trichotomum leaves.

Method Based on previous transcriptome data, 17 reference genes were selected under different abiotic stresses (salt, drought and heat) for C. trichotomum. Four reference gene analysis software i.e. GeNorm, NormFinder, BestKeeper and ReFinder were used to select the optimal internal reference gene, to select the genes for Na ⁺ /H ⁺ Exchanger1 (ClNHX1) and to verify the stability of internal reference genes elected.

Result Genes RPL and AP-2 were the most stable under salt stress; MDH and AP-2 were the most stable under drought stress; UBCE2 and ACT were the most stable under heat stress. For abiotic treatments, AP-2 and UBCE2 were the most stable reference genes.

Conclusion  AP-2 and UBCE2 can be used as internal reference genes for gene quantification in abiotic stress studies of C. trichotomum leaves. This study can provide reliable normalization for gene expression analysis and ensured more accurate data for further molecular mechanism research in C. trichotomum.