At about the same time two papers describe the use of gene editing of the strigolactone transporter to reduce strigolactone exudation and thereby introduce parasitic weed resistance in sorghum and tomato. These are:
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, 2025. Resistance to Striga parasitism through reduction of strigolactone exudation. Cell, 2025, ISSN 0092-8674, https://doi.org/10.1016/j.cell.2025.01.022
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 GR245DS 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.
and
Xinwei Ban, Li Qin, Jijun Yan, Jianxin Wu, Qianjin Li, Xiao Su, Yanrong Hao, Qingliang Hu, Liquan Kou, Zongyun Yan, Peiyong Xin, Yuqin Zhang, Lemeng Dong, Harro Bouwmeester, Hong Yu, Qinghui Yu, Sanwen Huang, Tao Lin, Qi Xie, Yuhang Chen, Jinfang Chu, Xia Cui, Jiayang Li, Bing Wang, 2025. Manipulation of a strigolactone transporter in tomato confers resistance to the parasitic weed broomrape. The Innovation, 2025, 100815, ISSN 2666-6758, https://doi.org/10.1016/j.xinn.2025.100815.
Parasitic weeds of the Orobanchaceae family cause substantial economic losses and pose significant threats to global agriculture. However, management of these parasites is challenging, and very few resistance genes have been cloned and characterized in depth. Here, we performed a genome-wide association study using 152 tomato accessions and identified SlABCG45 as a key gene that mediates host resistance to Phelipanche aegyptiaca by affecting the level of strigolactones (SLs) in root exudates. SLs are synthesized and released by host plants and act as germination stimulants for parasitic weeds. We found that SlABCG45 and its close homolog SlABCG44 are membrane-localized SL transporters with essential roles in exudation of SLs to the rhizosphere, resistance to Phelipanche and Orobanche, and upward transport of SLs from root to shoot. As a predominant environmental stimulant exacerbating parasitism, phosphorus deficiency dramatically induced SlABCG45 expression and weakly induced SlABCG44 expression via the transcription factors SlNSP1 and SlNSP2. Knockout of SlABCG45 in tomato had little effect on yield traits in a broomrape-free field, but conferred increased resistance to different Phelipanche and Orobanche species, resulting in an ∼30% yield increase in a Phelipanche-infested field. Our findings reveal that targeting a single gene by genome editing can confer broad-spectrum parasitic weed resistance in tomato, providing an effective strategy for the sustainable control of parasitic plants in agriculture.
An interesting new chapter in the manipulation of strigolactones in the quest for parasitic weed control.