**4. Materials and Methods**

### *4.1. Plant Materials*

*Phalaenopsis* 'Panda' (Figure 10) were grown at the horticultural farm of Hainan University (Latitude: 20.03N, longitude: 110.33E), Haikou, Hainan Province, China. The sepal tissues were divided into two parts, spots area and non-spots area for total anthocyanin analyses and totally RNA extraction. Three independent biological replicates were collected for each sample. All samples were immediately frozen in liquid nitrogen and stored at −80 ◦C until use.

**Figure 10.** The flower tissue of *Phalaenopsis* 'Panda'. Bars = 1 cm. (**A**) Full bud; (**B**) Sepal; I. spot area; II. non-spot area. (**C**) Full bloom stage.
