Plant mechanical strength contributes to lodging resistance and grain yield, making it an agronomically important trait in sorghum (Sorghum bicolor). In this issue, Li et al. (788–801) report that a mutation in brittle culm 1 (bc1) in sorghum leads to reduced mechanical strength, decreased cellulose content, and increased lignin content without altering overall plant morphology. SbBc1 encodes a COBRA-like protein that exhibits typical structural features of a glycosylphosphatidylinositol-anchored protein, homologous to rice OsBC1 and Arabidopsis thaliana AtCOBL4. The results provide further evidence for the role of COBRA-like genes in
cellulose biosynthesis in grasses.
The cover image shows a Sorghum bicolor bc1 mutant plant and, inset, images of two leaf sections showing the brittle and easily broken bc1 mutant leaf phenotype (left) against the wild type (right). Images supplied by Hongwei Cai (China Agricultural University, Beijing, China).