BRITTLE CULM16 (BRITTLE NODE) is required for the formation of secondary cell walls in rice nodes

• Published in: Journal of Integrative Agriculture Vol. 16; no. 6; pp. 1286 - 1293
• Main Authors: WANG, Ying, REN, Yu-long, CHEN, Sai-hua, XU, Yang, ZHOU, Kun-neng, ZHANG, Long, MING, Ming, WU, Fu-qing, LIN, Qi-bing, WANG, Jiu-lin, GUO, Xiu-ping, ZHANG, Xin, LEI, Cai-lin, CHENG, Zhi-jun, WAN, Jian-min
• Format: Journal Article
• Language: English
• Published: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy ofAgricultural Sciences, Beijing 100081, P.R.China%National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095,P.R.China 01.06.2017; Elsevier
• Subjects: brittle node; rice (Oryza sativa L.); sclerenchyma tissue; secondary cell wall; rice (Oryza sativa L.); secondary cell wall; brittle node; sclerenchyma tissue
• ISSN: 2095-3119
• DOI: 10.1016/S2095-3119(16)61536-8

Plant cell walls constitute the skeletal structures of plant bodies, and thus confer lodging resistance for grain crops. While the basic cell wall synthesis machinery is relatively well established now, our understanding of how the process is regulated remains limited and fragmented. In this study, we report the identification and characterization of the novel rice (Oryza sativa L.) brittle culm16 (brittle node; bc16) mutant. The brittle node phenotype of the bc16 mutant appears exclusively at nodes, and resembles the previously reported bc5 mutant. Combined histochemical staining and electron microscopy assays revealed that in the bc16 mutant, the secondary cell wall formation and thickening of node sclerenchyma tissues are seriously affected after heading. Furthermore, cell wall composition assays revealed that the bc16 mutation led to a significant reduction in cellulose and lignin contents. Using a map-based cloning approach, the bc16 locus is mapped to an approximately 1.7-Mb region of chromosome 4. Together, our findings strengthen evidence for discretely spatial differences in the secondary cell wall formation within plant bodies.