Objective  Applicability of the guidelines recently released by the International Union for the Protection of New Varieties of Plants (UPOV) for quantitative DUS traits determination and classification of Antirrhinum majus L. in China was examined.

  Method   An experimental planting of 40 germplasms of A. majus L. was conducted following the guidelines TG/221/1 issued by the UPOV. Thirteen DUS traits of the plants, leaves, flowers, and other parts were collected to statistically analyze their variations, classes, and principal components using SPSS for the application on the plant varieties in China.

  Result  The variation coefficients that met the selection criteria set by the guidelines were 16.91%-65.87% among different species and 5.29%-12.18% within a same species on 11 traits, which were specified by the guidelines, as well as two additional ones identified by this study. The expressions of these 13 traits differentiated by least significant difference could all be applied to adequately identify the germplasms and for the DUS guideline development on A. majus L in China. In addition to the 4 factors listed in the UPOV guidelines, the principal component analysis suggested 2 new criteria for the plant classification.

  Conclusion  The current UPOV guidelines provide quantitative DUS traits of A. majus L. germplasms for the species classification. A close examination with a specially designed experimentation revealed additional criteria on inflorescence length, plant height, and number of primary branches on the plant for establishing guidelines applicable in China.