LAUSR

Intraspecific haploid induction in maize (Zea mays) is triggered by a native frameshift mutation in MATRILINEAL (MATL), which encodes a pollen-specific phospholipase. To develop a haploid inducer in rice (Oryza sativa), we generated an allelic series in the putative ZmMATL orthologue, OsMATL, and found that knockout mutations led to a reduced seed set and a 2–6% haploid induction rate. This demonstrates MATL functional conservation and represents a major advance for rice breeding.A MATL gene mutation was found to induce haploids in maize. Now, knocking out the MATL orthologue in rice results in haploid induction at a rate of 2–6%, suggesting the functional conservation of MATL, and represents an advance for rice breeding.