Abstract: To clarify the candidate genes and expression of one ERF transcription factor in pepper(Capsicum annuum L. HDA149)during the incompatible interaction between HDA149 and Meloidogyne incognita, the core sequence of an ethylene transcription factor gene CaERF18 was isolated from pepper induced by M. incognita with RT-PCR. The cDNA core sequence was 694 bp, encoding 231 amino residues containing a conserved ERF motif of 59 amino acids that shared 44.3%, 42.6% and 39.3% identities with the motif of NtERF118, SlERF4 and SlERF19, respectively. The expression analysis revealed that the expression of CaERF18 was significantly induced by M. incognita, the relative expression level of CaERF18 began to increase at 12 h with 3.8 times, and 7.2 times(peak)of the control at 72 h after inoculation with M. incognita. The expression of CaERF18 was strongly up-regulated by the nematode inoculation, which implied that the gene might play an important regulatory role in the resistant interaction of C. annuum to nematode.

Key words: pepper, root-knot nematode, ethylene, transcription factor, induced expression