Rice is a staple crop for billions of people. By optimizing the size and branching pattern of the rice inflorescence, or panicle, rice breeders can potentially generate significant improvements in yield and grain quality. Susan McCouch and colleagues report in Nature Communications the identification of genetic loci associated with different panicle traits. The study is remarkable for its scale which involved assessing 49 observable traits from over 3400 images of rice panicles from 242 diverse lines of rice grown in the field. Association of these traits with 700,000 single nucleotide genome sequence variations (known as polymorphisms) led to identification of genetic loci contributing to panicle structure.
In contrast to some traits which are controlled by a small number of genes, many genetic loci contribute to panicle structure. Improvements of rice yield and quality through changes in panicle associated traits will likely involve introgressing multi-gene regions that span multiple beneficial alleles.