Recently, the international journal "New Phytologist" published online two high-quality genome sequences of spinach wild species. This research was completed by the spinach genetic breeding team led by Qian Wei from the Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences. It revealed the chromosome structure of spinach and deciphered its important domestication traits. This study holds significant importance for further utilizing wild spinach resources and breeding high-quality spinach varieties.
Two Wild Spinach Species: Spinacia tetrandra (a) and Spinacia turkestanica (b).
The white box indicates spinach stamens. Image provided by the Vegetable Research Institute of the Chinese Academy of Agricultural Sciences.
Spinach, originating from Persia (modern-day Iran), also known as Persian grass or red-rooted vegetable, was introduced to China as a tribute from Nepal during the Tang Dynasty. There are two different types of wild spinach species, S. turkestanica and S. tetrandra. Wild materials often possess strong adaptability and stress resistance, making them important resources for crop genetic improvement. However, the genomic information of the two wild spinach types remains unclear, hindering further utilization of wild spinach species. Therefore, deciphering the genome sequences of wild spinach species and identifying important genes related to domestication traits lay the foundation for breeding high-quality spinach varieties.
This study assembled two high-quality genome sequences of wild spinach species from scratch and analyzed the characteristics of their genome pericentromeric regions. It confirmed that S. turkestanica is the direct ancestor of cultivated spinach, with a divergence of approximately 0.8 million years ago; whereas S. tetrandra diverged even earlier, around 6.3 million years ago.
Furthermore, the study found that the locus for resistance to downy mildew in cultivated spinach gradually infiltrated from wild species. Additionally, a large number of domestication-related genes were identified, mainly associated with photoperiod, stress resistance, and disease resistance. This research provides theoretical guidance for further utilization of wild spinach resources and breeding high-quality spinach varieties.
Assistant Researcher Zhe Hongbing and Researcher Liu Zhiyuan from the Vegetable and Flower Research Institute of the Chinese Academy of Agricultural Sciences are the co-first authors; Researcher Qian Wei and Cheng Feng from the Vegetable and Flower Research Institute of the Chinese Academy of Agricultural Sciences, along with Professor Deborah Charlesworth from the University of Edinburgh, are the corresponding authors.
This research was supported by the National Key Laboratory of Vegetable Breeding, the Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences, and the Modern Agricultural Industry Technology System Project.
For more information, please refer to the related paper: https://doi.org/10.1111/nph.19799
