A LysM receptor LcLRK1 gene possibly involved in Myc-factor perception was isolated from Lotus corniculatus. The full-length of LcLRK1 gene was isolated from L. corniculatus by using the degenerate primers and RACE PCR strategies.The structure of LcLRK1 gene was analyzed with bioinformatics.The expression profiles of LcLRK1 gene were investigated in variant tissues from L. corniculatus after inoculation Rhizophagus irregularis.A recombinant plasmid harboring ProLcLRK1∶∶GUS reporter was constucted to localize LcLRK1 in the roots of L.corniculatus.The LcLRK1 gene was knock-down with RNA interference.The results showed that LcLRK1 gene,encoding a LysM receptor kinase,was comprised of three extracellular LysM domains,a transmembrane domain and intracellular kinase domain.LcLRK1 gene was up-regulated in roots at early stage of AM symbiosis and the transcripts of LcLRK1 were mainly present in the root epidemis and root hairs.The knock-down of the LcLRK1 gene significantly decreased AM fungal colonization.In RNAi lines,the infection rate and arbuscule numbers were strongly reduced compared to that in the controls.The LcLRK1 gene may participate in the perception of Myc-factor and down-regulation of LcLRK1,affecting the formation of AM fungal arbuscule.