Phenotypic and genomic changes during modern wheat breeding in China and the United States

Jianqing Niu et al. explore how modern breeding reshaped wheat phenotype and genome in China and the United States, which will facilitate breeding higher performance wheat in the future.

By Jianqing Niu and Hong-Qing Ling from Hainan Yazhou Bay Seed Laboratory and Institute of Genetics and Developmental Biology, Chinese Academy of Sciences.

Background: A landrace is a traditional plant variety capable of tolerating local biotic and abiotic stresses and maintaining intermediate yield levels in low-input farming systems. The development of cultivars from landraces was achieved by human-mediated selection aimed at higher yield, better quality, and stronger fitness. The transition from landraces to elite cultivars is regarded as crop improvement, during which beneficial alleles might gradually accumulate in cultivars. Therefore, understanding the genetic architecture of wheat improvement during the transition from landraces to cultivars in distinct geographic regions will be crucial for developing high-performance varieties in the future.

Question: How has modern wheat breeding reshaped the phenotypic and genomic architecture of wheat in China and the United States?

Findings: We performed a comprehensive comparative analysis (at the phenotypic and genomic levels) of a whole-genome resequencing panel of 355 common wheat accessions representing diverse landraces and modern cultivars from China and the United States. Compared with landraces, the genetic diversity, and phenotypes of modern wheat cultivars from China and the United States changed significantly. Furthermore, we identified breeding targets during modern wheat breeding and determined that breeding for increased productivity in these two geographic regions was accomplished by pyramiding both shared and region-specific variants.

Next steps: The unique loci selected either in China or the United States can be used to develop high-performance wheat varieties in the future.


Jianqing Niu, Shengwei Ma, Shusong Zheng, Chi Zhang, et al. (2023). Whole-genome sequencing of diverse wheat accessions uncovers genetic changes during modern breeding in China and the United States.