Herbicide‐resistant barnyardgrass (Echinochloa crus‐galli) in global rice production

Abstract

Barnyardgrass (Echinochloa crus-galli (L.) Beauv.), an annual species of the family Poaceae, is a major weed problem in rice-producing countries throughout the globe. Synthetic herbicides can effectively control this grass in rice paddies, but the development of resistant biotypes after the continuous use of the same active ingredients has led to low herbicide efficacy and yield losses. In this review, a summary of resistant-barnyardgrass cases in global rice production is reported based on data from the International Herbicide-Resistant Weed Database. The first case of resistant barnyardgrass in rice paddies was to the photosystem-II inhibitor propanil in the late 1980s. Eighty-five (85) out of 116 cases in the period from 1986 to 2022 refer to resistant barnyardgrass (E. crus-galli var. crusgalli, E. crus-galli var. formosensis and E. crus-galli var. zelayensis) in 16 countries.Barnyardgrass has been found resistant to acetolactate synthase (ALS) inhibitors (34 cases), acetyl-CoA carboxylase (ACCase) inhibitors (23 cases), photosystem-II inhibitors (11 cases), auxin mimics/cellulose biosynthesis inhibitors (9 cases), very long chain fatty acid inhibitors (6 cases), and microtubule assembly inhibitors (1 case). The majority of all resistance cases reported to the active ingredi-

Syntenic analysis of ACCase loci and target‐site‐resistance mutations in cyhalofop‐butyl resistant Echinochloa crus‐galli var. crus‐galli in Japan

“…Echinochloa crus-galli is a common and noxious weed in crop production worldwide. 11 The species is classified into multiple varieties, for example, E. crus-galli var. crus-galli and var.…”

Recurrent Selection of Echinochloa crus-galli with a Herbicide Mixture Reduces Progeny Sensitivity

“…Fenoxaprop- p -ethyl is an aryloxyphenoxypropionate herbicide that inhibits the ACCase enzyme and is used in rice fields to control grasses, especially E. crus-galli. , Because of the narrow spectrum of control, it is often used in a tank mix with different herbicide modes of action to provide a wider weed control spectrum. , Imazethapyr is an ALS inhibitor used in imidazolinone-tolerant rice varieties with efficacy on grasses, sedges, and broadleaves; however, resistance to imazethapyr has occurred in several rice areas worldwide, , and the mechanism of resistance is often associated with enhanced herbicide metabolism. ,, The herbicide mixture of fenoxaprop-p-ethyl and imazethapyr is a common practice by rice farmers to control resistant barnyardgrass biotypes; however, some studies showed that this mixture is often antagonistic. , The consequences of herbicide mixture applications over multiple years on herbicide resistance evolution in weeds are still unknown.…”

“…36,37 Imazethapyr is an ALS inhibitor used in imidazolinone-tolerant rice varieties with efficacy on grasses, sedges, and broadleaves; 38 however, resistance to imazethapyr has occurred in several rice areas worldwide, 10,39 and the mechanism of resistance is often associated with enhanced herbicide metabolism. 32,39,40 The herbicide mixture of fenoxaprop-p-ethyl and imazethapyr is a common practice by rice farmers to control resistant barnyardgrass biotypes; however, some studies showed that this mixture is often antagonistic. 15,37 The consequences of herbicide mixture applications over multiple years on herbicide resistance evolution in weeds are still unknown.…”

Echinochloa in mid-southern U.S. and California rice: What is known and what are the knowledge gaps?

“…Additionally, molecular analyses have provided recent insights into its evolution as a weed (Guo et al 2017; Wu et al 2022). Recently, global cases of herbicide resistance in barnyardgrass were reviewed (Damalas and Koutroubas 2023). With special reference to barnyardgrass, this article aims to 1) highlight the current state of knowledge on economically relevant Echinochloa species in U.S. rice production in terms of their introduction and persistence/adaptation in U.S. rice agroecosystems, provide a historical overview of their management and emerging herbicide resistance issues; and 2) identify the research needs for their sustainable management in U.S. rice on the cusp of a paradigm shift in weed management approaches.…”