A new study has decoded the genetics of modern roses, uncovering the combined influence of Eastern and Western species. The research provides valuable insights for breeding more resilient roses while emphasizing the importance of preserving genetic diversity.
Roses, cherished as one of the most beloved and widely cultivated ornamental plants, have captivated hearts and adorned gardens for centuries. Despite their long-standing popularity, much of the genetic origins and breeding history of modern roses has remained a mystery. However, a recent study has uncovered intriguing details about the evolution of modern roses from their ancestors, offering valuable insights for breeding more resilient and stunning varieties.
For millennia, roses were cultivated separately in China and Europe, with each region nurturing unique variations. The 18th century marked a turning point when Chinese roses were introduced to Europe, setting the stage for a breakthrough in rose breeding.
Traditionally, the ‘Old Blush’ China rose has been credited as a major player in this transformation. However, the recent study highlights the significant and previously underappreciated role of another species: Rosa odorata. The fusion of these Eastern and Western roses led to the modern roses we adore today, known for their repeated flowering and diverse forms.
Decoding the Genetics of Modern Roses
The research project began by decoding the complex genetic makeup of ‘Samantha®,’ a modern rose variety renowned for its stunning red flowers and continuous blooming.
“’Samantha®’ is a tetraploid, meaning it has four sets of chromosomes instead of the usual two, making its genetic structure more intricate and challenging to study,” said Zhangjun Fei, a professor at the Boyce Thompson Institute and one of the study’s lead authors. “By mapping its genome, we created a powerful resource for future comparative and evolutionary genomic studies and for advancing rose breeding efforts.”
The research team also sequenced the DNA of 233 other rose varieties, from wild types to modern cultivars. This allowed them to create a “genome variation map,” a reference for understanding how modern roses evolved from their ancestors.
With this resource, breeders can develop roses that are not only more beautiful but also hardier and better suited to various climates. Imagine roses that bloom longer, require less care, and are more resistant to pests and diseases.
The study, recently published in Nature Plants, found that human selection has significantly influenced the genetic diversity of modern roses. Over the years, traits such as continuous and recurrent flowering, double flowers, and disease resistance have been carefully cultivated.
However, the researchers emphasize that preserving a wide range of genetic traits is essential for the health and adaptability of these stunning flowers. In an era of climate change and environmental challenges, genetic diversity is crucial for ensuring that roses can continue to thrive in changing conditions.
This research opens new avenues for understanding and improving one of the world’s most cherished flowers. The story of the rose is a rich tapestry woven from threads of history, science, and human passion. Thanks to this study, that tapestry is more vivid and detailed than ever before.
Reference: “Haplotype-resolved genome assembly and resequencing provide insights into the origin and breeding of modern rose” by Zhao Zhang, Tuo Yang, Yang Liu, Shan Wu, Honghe Sun, Jie Wu, Yonghong Li, Yi Zheng, Haoran Ren, Yuyong Yang, Shaochuan Shi, Wenyan Wang, Qi Pan, Lijuan Lian, Shaowen Duan, Yingxiong Zhu, Youming Cai, Hougao Zhou, Hao Zhang, Kaixue Tang, Jiaopeng Cui, Dan Gao, Liyang Chen, Yunhe Jiang, Xiaoming Sun, Xiaofeng Zhou, Zhangjun Fei, Nan Ma and Junping Gao, 11 October 2024, Nature Plants.
DOI: 10.1038/s41477-024-01820-x