Resistance to Striga parasitism through reduction of strigolactone exudation

Jiayang Shi, Cuo Mei, Fengyong Ge, Qingliang Hu, Xinwei Ban, Ran Xia, Peiyong Xin, Shujing Cheng, 

Gaohua Zhang, Jiawei Nie, Shiqi Zhang, Xiaowei Ma, Yi Wang, Jinfang Chu, Yuhang Chen, Bing Wang, 

Weihua Wu, Jiayang Li, Qi Xie, Feifei Yu.

Cell; February 12, 2025 (on line)

Summary

Parasitism with Striga poses a major threat to global food production. Striga germination and growth rely on strigolactones (SLs) exuded by crop roots under phosphate (Pi)-deficient conditions, although the mechanism of this host-parasite interaction remains elusive. In this study, transcriptomic and functional analyses of sorghum treated with Pi deficiency or the SL GR24^5DS identify two ABC transporter G (ABCG) transporters of SL, Sorghum biocolor strigolactones transporter 1 (SbSLT1) and SbSLT2. Using AlphaFold2 and amino acid conversion mutants, we identify highly conserved amino acids in SL transport channels essential for transport function. Sorghum lines with single or double knockouts of these transporters exhibit significantly reduced SL secretion from roots, leading to decreased Striga germination and parasitism in field experiments and consequently reducing the grain loss under Striga infestation. This study thus describes the mechanism of SL exudation in monocots and defines conserved residues essential for SL transporter function, offering a potential strategy for enhancing crop resistance to Striga parasitism.

See https://www.cell.com/cell/abstract/S0092-8674(25)00086-8