Abstract: Abstract: [Objective]Seeking for the theory and techniques of selection breeding of high-yield rugosa rose cultivars, [method] the analysis of grey system, Kriging interpolation and integration selection index were employed to investigate the relationship between the flower yield per plant and 15 quantitative traits of 20 rugosa rose cultivars. [Results] The result showed that: The grey relational grade of the flower number/plant, the number of branch, the width of floral bud and the weight of single flower to the flower yield/plant were larger (> 0.5). Kriging interpolation simulation was applied to analyze the flower yield/plant. It was found that the value of target trait went up with increase of the number of flower/plant and the number of branch. Moreover, the indirect selection of either trait couldn’t get better improvement of flower yield/plant. [Conclusion] It’s necessary to improve flower yield/plant by multi-trait selection. The integration selection index I = + 0.3187x1 - 318.6 x2 + 670.1x4 + 6.3x8. Index heritability = 0.8014, selective response of the integration breeding value = 245.8811. This will provide theoretic base for genetic breeding of rugosa rose.

Key words: Rugosa Rose, Grey relational grade, Quantitative traits, Kriging interpolation, Index selection