Abstract: Restriction fragment length polymorphism (RFLP) analysis of the PCR amplified fragments of Polyphenol Oxidase (PPO) genes was applied for the characterization of genetic relationship and processing property of four tea accessions. Four restriction sites were investigated. The results of genetic parameters indicated that 4 restriction sites fitted Hardy-Weinberg equilibrium (P>0.05). The HpaⅡ restriction site showed high polymorphism and BsuRⅠrestriction site showed moderate polymorphism. There was a high relationship between genotype distribution of BsuRⅠ, HpaⅡrestriction sites and genetic background of accessions. The HpaⅡrestriction site in primer L7/L8 amplified region was of abundant polymorphism and a high relationship between genotype and processing property of different accessions. If the genotype was AA, existing of HpaⅡrestriction site, the cultivar was good for processing black tea. If the genotype was BB or AB, this restriction site could not be digested or could partly be digested by HpaⅡrestriction endonucleases, and the cultivar was good for processing green tea or oolong tea. The restriction patterns of F1 progenies of Qi Men No.4 × Chao An Da Wu Ye at HpaⅡ restriction site in primer L7/L8 amplified region showed that the segregation of HpaⅡ restriction site in F1 population was in accord with Mendelian heredity law (x²=0.23). From this research, BsuRⅠand HpaⅡ (in primer L7/L8 amplified region) restriction sites in PPO gene might be considered as two useful genetic markers for characterization of genetic relationship and identification of parents. HpaⅡ restriction site (in primer L7/L8 amplified region) could be recommended as a genetic marker to identify processing property of tea cultivars at forepart of tea plant breeding.

Key words: tea plant (Camellia sinensis), polyphenol oxidase gene, endonucleases, PCR-RFLP