RNA-Seq analysis reveals the mechanism in response to cold stress of peach cv ‘Dingjiaba’

BACKGROUND: ‘Dingjiaba’ is an important Prunus persica cultivar (cv) mainly grown in the Hexi corridor in northwest China, which has an inherited strong cold tolerance. OBJECTIVE: To compare the transcriptome and physiology data of leaves of cvs ‘Dingjiaba’ (D) and ‘Kanoiwa’ (K) following cold treatment at different time periods, in order to gain new insights into the mechanisms of cold adaptation in ‘Dingjiaba’. MATERIALS AND METHODS: We analyzed the transcriptomic and physiological data of leaves of D and K cvs exposed to 0 h (D0/K0), 2 h (D2/K2), 6 h (D6/K6) and 12h (D12/K12) cold stress. RESULTS: Low temperature stress caused membrane damage and led to increased rate of electrolyte leakage and increased MDA content. Cold stress induced the accumulation of soluble sugars, soluble proteins and proline in leaves of both cvs, with a lower increase in K compared to D. Transcriptome analysis identified 4,631, 5,069, 5,662 and 3,886 differentially expressed genes (DEGs) between D0 and K0, D2 and K2, D6 and K6 and D12 and K12, respectively. The differentially expressed genes significantly enriched in metabolic pathways and biosynthesis of secondary metabolites. We further validated the reliability of sequencing data of the RNA-Seq with Real-Time Quantitative PCR, which suggested that the expression trend of the RNASeq were same as RT-PCR. CONCLUSIONS: These results provide novel insights into a series of molecular mechanisms underlying physiological metabolism and defense.