S.cn (Y.Y.) Institute of Plant Protection, Sichuan Academy of
S.cn (Y.Y.) Institute of Plant Protection, Sichuan Academy of Agricultural Sciences, Chengdu 610066, China; [email protected] Correspondence: [email protected] (X.Z.); [email protected] (Y.L.); Tel.: +86-028-84590090 (X.Z.); +86-0571-63370333 (Y.L.) The very first two authors contributed equally to this work.Citation: Tang, W.; Liu, S.; Yu, X.; Yang, Y.; Zhou, X.; Lu, Y. The Basis of Tolerance Mechanism to Metsulfuron-Methyl in Roegneria SHP2 Formulation kamoji (Triticeae: Poaceae). Plants 2021, ten, 1823. doi/ ten.3390/plants10091823 Academic Editor: Simon Hodge Received: 3 August 2021 Accepted: 29 August 2021 Published: 1 SeptemberAbstract: Roegneria kamoji, a perennial monocot weed that belongs towards the tribe Triticeae (family: Poaceae), is definitely an emerging problematic weed in winter wheat (Triticum aestivum) fields in China. We’ve previously confirmed 4 R. kamoji populations tolerant to acetyl-CoA carboxylase (ACCase) inhibitors, and failed control of these populations by metsulfuron-methyl was observed. The objective of this study was to characterize the amount of tolerance to metsulfuron-methyl, the basis of tolerance mechanism, and cross-tolerance to acetolactate synthase (ALS) inhibitors in R. kamoji. A whole-plant dose esponse assay showed that plants of all R. kamoji populations (both from wheat fields and uncultivated areas) exhibited high tolerance to metsulfuron-methyl, depending on their 100 survival at 6-fold suggested field dose (RFD) and ED50 values 6.84-fold RFD, no susceptible population was identified. Gene sequencing indicated that no reported amino acid substitutions connected with resistance to ALS inhibitor have been discovered Succinate Receptor 1 Agonist drug inside the ALS gene amongst the R. kamoji populations. Pretreatment together with the known cytochrome P450 monooxygenases (CytP450) inhibitor malathion reduced the ED50 values of metsulfuron-methyl in two R. kamoji populations. These populations also exhibited crosstolerance to RFD of mesosulfuron-methyl and bispyribac-sodium. The activities of glutathione-Stransferase (GST) and CytP450 could possibly be induced by metsulfuron-methyl in R. kamoji, which can be related to the known tolerant crop wheat. This is the initial report elucidating metsulfuron-methyl tolerance in R. kamoji. The reversal of tolerance by malathion and the GST and/or CytP450 enhanced herbicide metabolism suggests that non-target-site mechanisms confer tolerance to metsulfuron-methyl in R. kamoji. Key phrases: prevalent Roegneria; ALS inhibitor; non-target site; cytochrome P450; glutathione S-transferasesPublisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.1. Introduction Roegneria kamoji is a popular perennial weed that belongs to Roegneria in the tribe Triticeae (Poaceae loved ones). It truly is extensively distributed across China, Korea, and Japan, and is normally discovered in hillside, grassland, urban green spaces, and field borders [1,2]. In recent years, R. kamoji has been discovered spreading in winter wheat (Triticum aestivum) fields in Hubei, Anhui, and Zhejiang provinces of China (Supplemental Figure S1), and has come to be a dominant weed in some regions [3,4]. It has been the practice of numerous farmers to use acetyl-CoA carboxylases (EC six.four.1.two, ACCase) inhibitors, including fenoxaprop-ethyl, clodinafop-propargyl, and pinoxaden for postemergence handle of graminaceous weeds in wheat [5,6]. Failed control of R. kamoji by fenoxaprop-ethyl was observed in both populations collected from wheat fields and uncultivated regions, which implies ther.
