Measurement and analysis of color difference of excellent ornamental Bletilla flowers in Southwest China

The color difference of excellent ornamental Bletilla flowers in southwest region was measured and analyzed, and its correlation with growth characteristics was explored. The germplasm resources of Bletilla striata, Bletilla ochracea, Bletilla formosana in southwest region were collected, and their apparent traits were measured. The petal color was measured under standard light source D65, and classified by CIELab color system. The results showed that the flower colors were divided into 8 color systems: purple, deep purple, pink purple, light purple, pink, light orange, light yellow, and yellow. There was a significant correlation between the color difference of flower color and flowering period, plant height, and flower stem height. The establishment of a color difference evaluation model could provide a reference basis for the breeding of improved varieties and parent selection of the ornamental Bletilla.