Work

Widespread occurrence of cyhalofop‐resistant Leptochloa chinensis in eastern China was mainly propelled by target‐site mutations

Year: 2025

Type: article

Abstract: BACKGROUND: Various mechanisms or factors may cause the wide infestation of herbicide-resistant weeds with different contributions, such as target-site resistance (TSR), non-target-site resistance (NTSR), hormesis, and dissemination of herbicide-resistant weeds. Here we tested this hypothesis in eastern China in Leptochloa chinensis, for which cyhalofop resistance is a major challenge to rice planting. RESULTS: Our results revealed that 30% of the total 242 populations held high (10 < RI < 100) or very high resistance (RI > 100) to cyhalofop. Resistance increased from north to south, and from transplanted rice fields to direct-seeded rice fields. Six mutant types conferring TSR to cyhalofop were found in 89% sampled populations, with 18% carrying two types, 2% carrying three types, and another 2% carrying four types of mutations. W2027C was the most frequent TSR mutation, present in 47.3% of sampled populations, followed by I2041N (21.8%), W1999C (20%), L1818F (20%), W1999G (5.5%) and C2088R (1.8%). Non-target-site resistance linked with P450 monooxygenases (P450) and glutathione S-transferases (GST) were observed in 7% and 10% cyhalofop-resistant populations sampled. No significant correlation between genetic and geographic distances were observed among cyhalofop-resistant populations. Hormetic effects of cyhalofop to L. chinensis were evident in 13% of overall populations. CONCLUSIONS: This study compared the contribution of different mechanisms towards herbicide resistance, revealed herbicide hormesis and revealed the distribution of resistance. Insights from this study could be important for weed management practices in other areas of the world. © 2025 Society of Chemical Industry.

Source: Pest Management Science

DOI: 10.1002/ps.8927

Authors: Guoqi Chen, Kai An, Jiahao Xue, Wei Deng, Zeyue Huang, Yang Xu

Institution: Yangzhou University

Language: English

Topic: Weed Control and Herbicide Applications

Subfield: Plant Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: bronze

Funders: Yangzhou University, Priority Academic Program Development of Jiangsu Higher Education Institutions