Wheat is a stable food for human kind worldwide. Wheat germplasm is the No. 1 resource for fundamental research, applied studies, and wheat breeding. However, current wheat cultivars in use today span a very narrow genetic landscape, mainly due to long-term human selection for genetic purity. We are now facing an urgent need to restore the rich gene pools in wheat so that we can continue to improve upon the crops we have.

Mutagenesis is a highly efficient approach to create novel germplasm. Many wheat mutant populations have been created worldwide such as the tetraploid ‘Kronos’ population at the University of California, the hexaploid ‘Cadenza’ population at the John Innes Centre, UK, and the hexaploid ‘Aikang 58’ population at the Chinese Academy of Agricultural Sciences, China. However, each of these populations have comparatively few mutants, from one to five thousand lines. A thousand times that number are going to be needed to support a strong research program that can advance wheat breeding for value-added traits.

Here, we report chemical- and irradiation-induced mutagenesis in Chinese wheat cultivars. Firstly, we performed chemical mutagenesis using ethyl methanesulfonate (EMS), and created over 160k sets of mutants (1-5 mutant lines per set), including ‘Jimai 38’ (45k sets), ‘Jimai 44’ (45k sets), ‘Luyan 128’ (25k sets) and ‘Shannong 30’ (45k sets). Secondly, we performed irradiation mutagenesis using cobalt 60 (60Co), and created about 4.15 million mutants, including ‘Bainong 4199’ (370k lines), ‘Gaoyou 5766’ (170k lines), ‘Jimai 44’ (720k lines), ‘Luyan 128’ (590k lines), ‘Malan 1’ (390k lines), ‘Shannong 28’ (420k lines), ‘Shannong 30’ (300k lines), ‘Yannong 1212’ (310k lines), ‘Zhongmai 578’ (500k lines) and ‘Zhongxinmai 998’ (380k lines). This million-scale mutant collection will be an open resource for fundamental research and breeding. We will set up high-throughput screening for diverse agronomic traits such as tolerance/resistance to herbicides, powdery mildew, rust, salt-alkali, and drought. We will randomly select 10k EMS mutants and develop an open resource with both exome capture and high-throughput phenotyping data. We are willing to share the resource with non-profit organizations to better serve global agriculture.