Does selective hormesis impact herbicide resistance evolution in weeds? ACCase‐resistant populations of Alopecurus myosuroides Huds. as a case study

Abstract

As a consequence of population heterogeneity, herbicide hormesis may impact resistance evolution in weeds at realistic use rates via the selective promotion of individual genotypes. However, the practical relevance of this phenomenon may be influenced by many factors, such as the herbicidal active ingredient used, as indicated in this study. © 2018 Society of Chemical Industry.

Herbicide hormesis can act as a driver of resistance evolution in weeds – PSII‐target site resistance in Chenopodium album L. as a case study

“…This is unlikely to be generally the case for every compound and type of resistance. For example, in a study with an ACCase‐TSR biotype of A. myosuroides with a Leu1781 mutation, the regular field rate of the ACCase inhibitor fenoxaprop‐P proved too low to be in the hormetic dose range of R plants, whereas the field rate of clodinafop almost provided a maximum growth stimulation . Nevertheless, our knowledge in this area is still insufficient to draw any conclusions on compounds and resistance mechanisms that will be more prone to show evolutionarily relevant hormesis.…”

“…For example, in a study with an ACCase-TSR biotype of A. myosuroides with a Leu1781 mutation, the regular field rate of the ACCase inhibitor fenoxaprop-P proved too low to be in the hormetic dose range of R plants, whereas the field rate of clodinafop almost provided a maximum growth stimulation. 47 Nevertheless, our knowledge in this area is still insufficient to draw any conclusions on compounds and resistance mechanisms that will be more prone to show evolutionarily relevant hormesis. Regular application of the triazinone metamitron clearly poses a high risk of eco-evolutionary relevant hormesis in a Ser264 genotype of C. album.…”

Nitrogen availability and glyphosate hormesis on white oat

“…Herbicide hormesis can be accompanied by undesirable effects in non-target plants, among which are the induction of pathogen defenses in plants (Dann et al, 1999), the evolution of herbicide resistance (Belz et al, 2018), an increase in the reproductive capacity of weeds (Gomes, 2014), and an increase in competitive weeds (Abbas et al, 2016). The application of low rates of glyphosate has a positive impact on the development and yield of crops; however, their use as a form of agronomic recommendation should be done very carefully, since the results can be variable depending on the rates, crops stages, climatic conditions and nutritional status of plants (Belz and Duke, 2014;Cedergreen et al, 2016).…”

Glyphosate-induced hormesis: impact on seedling growth and reproductive potential of common sowthistle (Sonchus oleraceus)

“…This aspect is relevant from an agroecosystem perspective, where low glyphosate doses will appear in practice from spray drift, faultiness in herbicide application, surface contact of treated and nontreated plants, or shading by taller plants. Under such scenarios, changes in weed species composition, and hence herbicide susceptibility, are expected (Belz and Duke 2017;Cedergreen 2008aCedergreen , 2008b. Growth stimulation caused by ultralow herbicide doses has recently been demonstrated as an important factor conducive to herbicide-resistance development, and hormetically boosted resistant biotypes are expected to be more competitive (Farooq et al 2019).…”

“…Likewise, another study found a 54% increase in biomass of an acetyl-CoA carboxylase target-site resistant (TSR) biotype of blackgrass (Alopecurus myosuroides Huds.) compared with the control at doses that caused phytotoxicity to the susceptible biotype (Belz et al 2011(Belz et al , 2018Petersen et al 2008). Other studies also documented 31% and 64% growth stimulation of ALS TSR biotypes of scentless false mayweed [Tripleurospermum perforatum (Mérat) M. Lainz] and perennial ryegrass (Lolium perenne L.) in response to ALS-inihibiting herbicides (Belz 2014;Menegat et al 2016).…”