Multiple resistance of silky windgrass to acetolactate synthase- and acetyl-CoA synthase–inhibiting herbicides

Abstract

Field and pot experiments were conducted in Greece to study the occurrence of resistance in silky windgrass to acetolactate synthase (ALS)- and acetyl-CoA synthase (ACCase)-inhibiting herbicides. Twenty-four populations of silky windgrass were examined in whole-plant response experiments. High levels of field-evolved resistance to chlorsulfuron (0 to 28% control in terms of fresh weight reduction) with the recommended field rates were confirmed in most silky windgrass populations. However, other ALS inhibitors like pyroxsulam and the premix of mesosulfuron methyl and iodosulfuron provided adequate control (76 to 100% in terms of fresh weight reduction) of most populations, except eight silky windgrass populations that were found cross-resistant to all ALS-inhibiting herbicides tested (i.e., chlorsulfuron, commercial mixture of mesosulfuron methyl plus iodosulfuron, and pyroxsulam). Conversely, most silky windgrass populations were controlled effectively (90 to 100% in terms of fresh weight reduction) with the recommended field rates of ACCase-inhibitors cycloxydim, clethodim, and pinoxaden, but five populations were also found to be resistant to clodinafop-propargyl (10 to 68% control in terms of fresh weight reduction). The ALS gene sequencing of the eight silky windgrass populations, with cross-resistance to ALS-inhibitors, revealed a point mutation at Pro-197 position, causing amino acid substitution by Ser or Thr in the ALS enzyme. Overall, chlorsulfuron and clodinafop-propargyl were selecting agents of field-evolved multiple resistance to ALS- and ACCase-inhibiting herbicides in five silky windgrass populations. As the available postemergence applied chemistries/modes of action registered for grass weed control in cereals are rather limited, adopting integrated management practices and implementing proactive and reactive measures to delay the evolution of resistant populations is essential.

Comprehensive insights into herbicide resistance mechanisms in weeds: a synergistic integration of transcriptomic and metabolomic analyses

“…However, repeated use of similar herbicidal modes of action (MOAs) and the associated selection pressure have led to the evolution of herbicide resistance in varieties of economically important weedy species such as Alopecurus myosuroides ( Lan et al., 2022 ; Goldberg-Cavalleri et al., 2023 ), Amaranthus palmeri ( Manicardi et al., 2023 ), Apera spica venti ( Košnarová et al., 2021 ; Papapanagiotou et al., 2022 ), Bromus sterilis ( Sen et al., 2021 ), Lolium spp ( Tehranchian et al., 2019 ; Ma et al., 2020 ; Zhu et al., 2023 ). Recent studies showed that the majority of these weeds were also developing multiple resistances against herbicides with more than one mode of action ( Tehranchian et al., 2019 ; Ma et al., 2020 ; Košnarová et al., 2021 ; Lan et al., 2022 ; Papapanagiotou et al., 2022 ; Zhu et al., 2023 ). From a molecular point of view, herbicide resistance mechanisms might be categorized into target-site based resistance (TSR) and non-target-site based resistance (NTSR) ( Torra and Alcántara-de la Cruz, 2022 ).…”

“…Herbicides have been used to control weeds and increase the quality and quantity of major crops since their discovery. However, repeated use of similar herbicidal modes of action (MOAs) and the associated selection pressure have led to the evolution of herbicide resistance in varieties of economically important weedy species such as Alopecurus myosuroides (Lan et al, 2022;Goldberg-Cavalleri et al, 2023), Amaranthus palmeri (Manicardi et al, 2023), Apera spica venti (Kosňarováet al, 2021;Papapanagiotou et al, 2022), Bromus sterilis (Sen et al, 2021), Lolium spp (Tehranchian et al, 2019;Ma et al, 2020;Zhu et al, 2023). Recent studies showed that the majority of these weeds were also developing multiple resistances against herbicides with more than one mode of action (Tehranchian et al, 2019;Ma et al, 2020;Kosňarováet al, 2021;Lan et al, 2022;Papapanagiotou et al, 2022;Zhu et al, 2023).…”