Effect of light quality on the growth and main chemical composition of Bletilla striata

This study aimed to investigate the effects of light quality on the morphological traits, photosynthetic pigment content, protective enzyme (superoxide dismutase, peroxidase, and catalase) activity, and bioactive compound (BSP, total phenol, and militarine) content in Bletilla striata. Plants of B. striata were grown under light filtered through three differently colored films. The treatments were red film (RF), yellow film (YF), and blue film (BF), and an uncovered treatment was included as a control (CK). Compared with the B. striata plants in the RF, YF, and CK treatment groups, those receiving BF treatment showed significantly promoted growth of the aerial parts. Meanwhile, the total phenol and militarine contents in B. striata tubers were increased without affecting the accumulation of B. striata polysaccharides. These results show that growing B. striata plants under blue film could be a useful technique to improve quality and production. This technique is conducive to achieving large-scale sustainable production of high-quality plant materials.