Abstract: 【Objective】 It is a fundamental work to identify grape germplasm materials and cultivars for exploration and collecting of germplasm resources as well as plant variety protection. A new approach (manual cultivar identification diagram, MCID) by using RAPD marker was adopted to distinguish 72 cultivars of grape germplasm from different countries and areas. 【Method】 In this study, based on the optimization of RAPD through increasing the length of the RAPD primers and strict screening PCR annealing temperature, 6 effective primers were screened from 35 RAPD arbitrary 11-mer primers, and in which 6 effective primers had clear amplification products and amplified polymorphic bands, and furthermore to conduct PCR amplification. Using this strategy of MCID, all the cultivars were gradually and completely separated by a combination of the 6 primers. 【Result】A manual cultivar identification diagram (MCID) of the 72 grape cultivars was constructed using polymorphic bands from the DNA fingerprints. The MCID method could separate all the cultivars from each other, with the polymorphic bands employed for identifying the cultivars and the corresponding primers being marked in the correct position on the MCID. 【Conclusion】So far, the MCID method is the best and most effective one to realize the identification of fruit cultivars by using DNA molecular markers. The MCID of 72 grape cultivars has high operability and practicability in identifying varieties using DNA markers, which can be of much help in grape cultivars identification for protection of cultivar rights and for early identification of seedlings in the nursery industry, thus providing a theoretical basis for germplasm evaluation and cultivar identification.

Key words: grape, RAPD, cultivar identification