Abstract:In order to study the biological function of TrFQR1 in Trifolium repens cv. ‘Ladino’, we cloned cDNA sequence of TrFQR1 by RACEPCR and RTPCR and analyzed with bioinformatics software. The expression pattern of TrFQR1 was detected by realtime fluorescence quantitative PCR(RTqPCR). The results showed that: (1) TrFQR1 was obtained at a length of 1 003 bp, which open reading frame contained 612 bases and encoded 203 amino acid. The molecular weight was 21.88 kD and the isoelectric point was 5.96. TrFQR1 was a hydrophilic protein that highly conserved in evolution without signal peptide and transmembrane domains. The N terminal 11-15 aa and the C terminal 112-165 aa were the FMN binding sites. (2) RTqPCR results showed that TrFQR1 could respond to the all eight treatments. However, TrFQR1 presented different expression trends to those treatments. At 1.5 h after the treatment of 25 μmol/L SNP, 10 mmol/L H2O2 or 5 mmol/L CaCl2 and 3h after the treatment of 15% PEG, the relative expression levels of TrFQR1 were upregulated significantly. The relative expression levels of TrFQR1 increased with the increase of treatment time under 200 mmol/L NaCl or 600 μmol/L CdSO4. The relative expression of TrFQR1 gene were significantly decreased at 6 h after the treatment of 4 ℃ and 1.5 h after the treatment of 0.02 mmol/L NaHS.