Lotus (Nelumbo nucifera) is one of the top ten traditional Chinese famous flowers, which serves as a source of valuable ornamental plants. Flowers with bright color trend to be more attractive to consumers. However, the flower color of lotus easily fades after flowering, which reducing its ornamental quality.

Supervised by Prof. YANG Mei from Wuhan Botanical Garden, researchers investigated the petals form four developmental stages of ‘Qiusanse’ cultivar with an obvious rapid floral-color fading phenotype for RNA-sequencing to reveal the transcriptome profile of anthocyanin discoloration in lotus.

Results revealed a decreasing trend in the total anthocyanin content during lotus petal development. The petal discoloration resulted from a combined impact of reduced anthocyanin biosynthesis and its increased degradation. Down-regulation of pathway structural genes by transcription factors, such as NnMYB5, caused the decrease in anthocyanin content. The observed increase in peroxidase activity during color fading revealed their potential role in regulating floral color change in lotus.

This study revealed the dynamic transcription process of lotus petal fading for the first time, and provided candidate genes and theoretical basis for improving lotus ornamental value.

It was funded by the National Natural Science Foundation of China, Biological Resources Programme of CAS and Key Research Program of Frontier Science of CAS.

Result have been published in Plant Physiology and Biochemistry entitled “Color fading in lotus (Nelumbo nucifera) petals is manipulated both by anthocyanin biosynthesis reduction and active degradation”.

Proposed model of molecular mechanism underlying petal discoloration in lotus (Image by WBG)