Studies on Genetic Relationship Analysis of 16 Phalaenopsis hybrid Cultivars by ISSR Molecular Marker Technology

By optimizing DNA extraction method,annealing temperature,amplification of cycle number and Mg2+ concentration,we established an optimal ISSR-PCR reaction system for Phalaenopsis in this study.8 primers were used to generate 193 brands of DNA fragments,the average percentage of polymorphic bands was 92.2%,and the range of amplified fragments was 300~2 500 bp.This result indicated that the tested species possessed abundant genetic polymorphism.The 16 species of Phalaenopsis can be divided into 2 groups at L=0.222 5,one stand for Japanese/Taiwan species,and the other is for species newly cultured by the Company.The potential hybrid combinations of different species were suggested according to the affinity distance determined by molecular marker.The establishment of ISSR molecular marker system in Phalaenopsis has provided theoretical basis for analyzing genetic relationship of Orchidaceae ornamental plants.