BACKGROUND

Plant anthocyanins are a secondary metabolite widely distributed in the roots, stems, leaves, flowers, and fruits of plants, and their synthesis is significantly affected by light intensity. To investigate the synthesis of anthocyanins in leaves under different light intensities is essential.

METHODS

Using the commonly colored leaf variety 'Emerald' as the control group, and the red-leaf varieties 'Red Ruyi', 'Angel', and 'Gilly Red' as the experimental material, three light intensities were set: 254368 μmol·m·s (CK), 588678 μmol·m·s (T1), and 1125~1267 μmol·m·s (T2).

RESULTS

The changes in anthocyanin content and anthocyanin-related gene expression in the leaves of with different leaf colors under different light intensities were studied. The results show that the anthocyanin content of leaves had a different trend compared to with increasing light intensity, and the appropriate light intensity could significantly promote anthocyanin synthesis after a certain time, and vice-versa. The anthocyanin content of CK and the T1 treatment was 1.14-3.72 times that of the T2 treatment; the photosensitive genes PHYB, CRY, and UVR8 were correlated with the anthocyanin synthesis of 'Angel' and 'Gilly Red'. The anthocyanin structural genes , , and were correlated with the anthocyanin synthesis of 'Red Ruyi', 'Angel', and 'Gilly Red'. The anthocyanin transcription factor was strongly correlated with the anthocyanin synthesis of 'Angel'.

CONCLUSIONS

As a byproduct from leaves with ornamental value and potential economic value, this study was helpful to understand the potential mechanism of leaves where light intensity regulates anthocyanin synthesis and accumulation.