LAUSR

• Haploid induction (HI) can create true-breeding lines in a single generation, which significantly accelerates the breeding process. In recent years, scientists have developed a variety of new techniques to induce haploids through the manipulation of the CENH3, a variant of centromere-specific histone H3. One alternative approach is based on CENH3 point mutations derived from EMS/TILLING, which is not lethal and yet responsible for its ability to induce haploid. However, most residues were obtained by EMS mutagenesis over a lengthy period of time. • Recently, a new approach called "base editing" was developed in plant. Here, we report a new method that uses a cytosine base editor (CBE) to create a point mutation of CENH3 as a haploid induction line, which substitute adenine (A) to guanine (G). • As a proof of the extreme simplicity of this approach to create haploid-inducing lines, we identified an L130F substitution within the histone fold domain in Arabidopsis thaliana. Subsequently, we tested the haploid inducing potential of homozygous L130F plants by pollinating them with Col-0, and we found that 2.9% paternal haploid plants. • In brief, our innovative technology provides a new perspective for the promotion of CENH3-mediated haploid induction in crops and also provides a variety of options for breeders. Such conserved point mutations as L130F could be developed into a general instrument for haploid induction in a wide range of plant species. Extending of these systems would represent a major advancement over haploid production.