WUSCHEL-D1 upregulation enhances grain number by inducing formation of multiovary-producing florets in wheat
- Adam Schoen
- Guilherme V. Yoshikawa
- Parva Kumar Sharma
- Alex Mahlandt
- Yi Chen
- Huajin Sheng
- Leon Kochian
- Peng Gao
- Daoquan Xiang
- Teagen D. Quilichini
- Prakash Venglat
- Sheng Wang
- Inderjit Singh Yadav
- Robert Sablowski
- Yuqi Wang
- Peng Zhang
- Annabel Whibley
- Amy Hill
- Yong Gu
- Daniel Rodriguez-Leal
- Weifeng Luo
- Yiping Qi
- Nathan Meier
- Anmol Kajla
- Matthew Willman
- Gina Brown-Guedira
- Sheron A Simpson
- Ramey C. Youngblood
- Amanda Hulse-Kemp
- Angus Murphy
- Bikram Gill
- Cristobal Uauy
- Raju Datla
- Nidhi Rawat
- Scott A. Boden
- Vijay Tiwari
2025-10-14
Innovative genetic improvements in food crops are needed to maintain global food security. Here, we report the map-based cloning of TaWUSCHEL-D1 ( WUS-D1 ) as the gene responsible for the multiovary phenotype in wheat, which produces three fertile ovaries and grains per floret. We generated a 14.5 Gbp chromosome-level assembly of multiovary wheat line “MOV” that shows unique structural variation in the Mov-1 physical region, resulting in widespread gene upregulation. High-resolution genetic mapping refined the locus to a 135 kbp region that contains two genes. We used nine independent deletion mutants, eight TILLING mutants, and genetic complementation of these genotypes to show that a WUSCHEL ortholog, WUS-D1 , is the causal gene of the Mov-1 locus. Expression studies showed that WUS-D1 is highly expressed during early inflorescence development in MOV, whereas the gene is inactive in wild-type wheat. The higher WUS-D1 expression is associated with the formation of larger meristems and floret primordia that are competent to produce multiple ovaries. These insights provide a foundation to manipulate floral organ numbers to enhance breeding capabilities of bread wheat.