Abstract: The optimal ISSR-PCR system for Paris vertcillata was established with orthogonal design.A total of 20 μL ISSR-PCR system contains 1×buffer, dNTP 175 μmol·L^-1，Primer 0.6 μmol·L^-1，Mg²⁺ 1.4 mmol·L^-1，Taq DNA polymerase 2.5 U and 80 ng template DNA.The suitable PCR procedure is one cycle denaturing at 95℃ for 5 min;40 cycles each involved denaturing at 94℃for 40 s,annealing at 55℃ for 45 s,extending at 72℃ for 90 s,one cycle extending at 72℃ for 7 min,and then remaining at 4℃.This optimized system would play an important role in further research of systematology on P.vertcillata and its related species, as well as identification on germplasm, and genetic diversity by ISSR molecular marker.

Key words: Paris vertcillata, ISSR-PCR, molecular markers, orthogonal optimization