Relationship between Flower Color and Cellular Physicochemical Factors in <i>Bletilla striata</i>

Flower color not only determines the quality and commercial value of ornamental plants, but it also plays a vital role in ecological processes such as pollinator attraction. This study aimed to investigate the relationship between flower color and the cellular physicochemical factors of <i>Bletilla striata</i>. The color space values of 21 samples were initially determined, followed by a selection of five samples with significant color differences for testing cell shape, total flavonoid content (ranging from 1.86 to 5.42 mg/g), total anthocyanin content (ranging from 0.52 to 292.62 (A530 − 0.25 ∗ A657)/g), cell pH (varying between 5.03 and 5.74), and metal ion content (including Al³⁺, Ca²⁺, Fe³⁺, K⁺, Mg²⁺, Na⁺, P⁵⁺, Zn²⁺, Mo⁶⁺, Cu²⁺, and Mn²⁺). The flowers of <i>Bletilla</i> were predominantly purple, pink, and yellow; and distributed in quadrants I, II, and IV on the a* and b* rectangular coordinate. The a* value was identified as the primary color indicator for this species. Total anthocyanin content and Zn²⁺ showed a significant positive correlation with a*, while Al³⁺, Ca²⁺, Fe³⁺, Mg²⁺, Na⁺, and Mn²⁺ demonstrated negative correlations. Cell shape, flavonoid content, and pH had nonsignificant correlations with a*. In conclusion, the total anthocyanin content and metal ions play crucial roles in determining the flower color of <i>B. striata</i>, which can have implications for pollinator attraction. Future research should focus on understanding the complex interactions between these factors to develop novel ornamental plant varieties with desirable flower colors and enhanced ecological functions.