Selection Of Suitable Reference Genes For Rt-Qpcr Normalisation In Sweet Potato (Ipomoea Batatas L.) Under Different Stresses

Sweet potato is an important crop that produces starch, dietary fibre, beta-carotene, and anthocyanin used as food and for industrial use. Recent studies have focused on the expression of genes involved in beta-carotene and anthocyanin biosynthesis, and real-time quantitative PCR (RT-qPCR) has been the main technique used for assessing these genes. For RT-qPCR, suitable reference genes for gene expression normalisation are very important. Herein, eight reference genes were detected in three sweet potato varieties ('Fucaishu18', 'Fucaishu23', and 'Ornamental Yellow (OY)') under different experimental conditions by RT-qPCR. The mRNA expressions of these eight reference genes were then evaluated comprehensively using GeNorm, NormFinder, BestKeeper and RefFinder software. The results of analysis with RefFinder showed that the most reliable reference genes for analysing gene expression in different sweet potato tissues wereTUAandEF1 alpha. Additionally,EF1 alpha andeIF4 alpha had the most stable expression under cold stress and drought stress, whileACTandEF1 alpha showed the most stability under salt stress, heavy stress and hormone stress. Two or more reference genes were required for accurate gene expression normalisation. The eight candidate reference genes were selected to investigate the expression pattern of the target geneUVR8in different sweet potato tissues. This study should benefit future studies of gene expression in sweet potato.