Recently, the innovative team for functional components and biosynthesis of tobacco of Tobacco Research Institute of Chinese Academy of Agricultural Sciences have completed the assembly of the first nearly complete genome of northern wild rice (Zizania palustris L.), providing valuable resources for genetic improvement, functional gene analysis, and key biological process research of Zizania crops. The relevant research results were published in The Crop Journal and reported on by the global science news release platform "EurekAlert!" hosted by the American Association for the Advancement of Science.

As an important wild relative of cultivated rice, the northern wild rice is an annual aquatic specialty crop, and its grain (wild rice) is known as the "caviar of grains". The production of northern wild rice, which has undergone human domestication, is relatively high, and a complete industrial chain of planting, harvesting, processing, and sales has been formed. Due to limitations in genome quality, research on the northern wild rice is relatively weak.

This study assembled a 1.41Gb genome of northern wild rice, with a long terminal repeat assembly index of 29.9. Through sequence connection filling, this study anchored 99.99% of the assembled sequences to 15 chromosomes. This study found that Z. palustris and Z. latifolia have the closest genetic relationship, with a differentiation time of 4.57-8.15 million years ago. Both have undergone whole genome replication and have obvious species differentiation signals. This study identified two highly collinear regions with the rice phytocassane biosynthetic gene cluster, which have two copies in the genomes of both Z. palustris and Z. latifolia, replicated from the whole genome and accompanied by genome fragmentation.

This work was funded by the Youth Innovation Program of the Chinese Academy of Agricultural Sciences and the Natural Science Foundation of Shandong Province.

Article Link: https://doi.org/10.1016/j.cj.2025.08.008

News Link: https://www.eurekalert.org/news-releases/1100046

By Yan Ning (yanning@caas.cn)