Water lily research: Past, present, and future
Xianghui Xiong, Ji Zhang, Yongzhi Yang, Yuchu Chen, Qun Su, Ying Zhao, Jian Wang, Zhiqiang Xia, Liangsheng Wang, Liangsheng Zhang, Fei Chen
Abstract
The water lily order Nymphaeales includes ~100 species and all grow into aquatic herbs. Most of them are not only economic crops but have, for thousands of years, been regarded as cultural symbols, especially in Buddhism and Hinduism. Water lily order forms an early angiosperm branch, occupying vital roles in evolutionary biology. With the advent and rapid development of omic techniques and bioinformatic software, the research on water lily biology has achieved unprecedented success. In this review, we summarized a series of recent and important findings in water lily research. Genomic analyses of water lilies provide insights into details of their evolutionary history and ecological adaptation. The genomes also provide rich resources for genetic studies and molecular breeding. The opening and closing rhythm of flowering is controlled by auxin and the candidate genes are proposed. Part of the genes responsible for floral scents and floral colors in <italic>Nymphaea colorata</italic> have been studied in-depth for their functions. Metabolomic profiling reveals the anthocyanins responsible for the floral color formation and the volatile organic compounds as floral scent molecules. Phenotypic studies surveyed the diverse traits from flowers to leaves and bulb roots, and some of these studies reveal the link between genes and phenotypes. However, genes responsible for some critical traits such as the growth of water lily plants, such as the stem, bulb formation, and the initiation of vivipary are still unknown. Finally, we propose potential future research of water lilies, including genetics, breeding, and industrialization.