Characterization of <i>SHATTERPROOF</i> Homoeologs and CRISPR-Cas9-Mediated Genome Editing Enhances Pod-Shattering Resistance in <i>Brassica napus</i> L.
Qamar U. Zaman, Wen Chu, Shi Yuqin, Hao Mengyu, Mei Desheng, Jacqueline Batley, Zhang Baohong, Chao Li, Qiong Hu
Abstract
Brassica napus is the most important oil crop plant for edible oil and renewable energy source worldwide. Yield loss caused by pod shattering is a main problem during B. napus harvest. In this study, six BnSHP1 and two BnSHP2 homoeologs were targeted by the CRISPR (clustered regularly interspaced short palindromic repeats)-Cas9 (CRISPR-associated protein 9) genome editing system and multiple SHP1 and SHP2 mutated lines were identified for evaluating the contribution for pod-shattering resistance. Our data suggest that BnSHP1A09 is probably a promising homoeolog for controlling lignin contents at dehiscence zone. Simultaneous mutation of BnSHP1A09/C04-B/A04 and BnSHP2A05/C04-A exhibited reduced lignified layer and separation layer adjacent to valves and replum. The pod-shattering resistance index (SRI) subsequently increased to 0.31 in five homoeolog mutation lines compared with the wild type (SRI = 0.036), which provide the theoretical basis for breeding of commercial pod-shattering resistance variety.