Differences in growth and herbicide sensitivity among Cyperus esculentus clones found in Belgian maize fields

Abstract

Summary Cyperus esculentus is an invasive troublesome neophyte in many arable crops in Belgium. Applied weed control varies from field to field. One of the possible reasons for this variability might be a differential vegetative and reproductive behaviour among Belgian C. esculentus clones. In this study, growth characteristics and herbicide sensitivity of C. esculentus clones collected in Belgian maize (Zea mays) fields were evaluated. In a morphology Experiment, 25 clones were screened for growth characteristics and ability to set viable seeds under outdoor conditions. Dose–response experiments were conducted in the glasshouse to evaluate the effectiveness of two foliar‐applied herbicides (bentazon and glyphosate) and two pre‐sowing soil‐incorporated herbicides (S‐metolachlor and dimethenamid‐P) for controlling 14 C. esculentus clones. Response variables were aboveground dry biomass, tuber number, tuber dry biomass and individual tuber dry weight. Clones exhibited large differences in shoot number (up to 3.1‐fold), tuber dry biomass (up to 4.7‐fold), tuber number (up to 3.4‐fold), individual tuber dry weight (up to 4.8‐fold), inflorescence number and capacity to set viable seeds. Large interclonal differences in herbicide sensitivity (up to 8.3‐ and 4.0‐fold for aboveground dry biomass and tuber dry biomass, respectively) were observed. Contrary to foliar‐applied herbicides, soil‐incorporated herbicides were very effective and provided season‐long C. esculentus control at doses below the recommended maximum field dose. However, low doses stimulated tuber formation. Future C. esculentus management strategies should take into account differential growth characteristics and herbicide sensitivity of C. esculentus clones.

Hyperspectral Classification of Cyperus esculentus Clones and Morphologically Similar Weeds

“…Average normal temperature and total sunshine duration are 17.5 °C and 578.2 h, respectively. The second Experiment was conducted in 2019 in Melle and investigated the hyperspectral distinctiveness of different C. esculentus clones and its impact on the model created in Experiment I. Clonal populations used in Experiment II, sampled by De Cauwer et al [3], were found in Belgian maize fields and were morphologically and genetically distinct. In each 10 L pot, a tuber was planted.…”

“…Mulligan and Junkins [17] stated that there exists evidence of significant genetic differences among C. esculentus populations and that these differences are relevant to the control of the species. De Cauwer et al [3] observed large interclonal differences in herbicide sensitivity in Belgian C. esculentus clones. Additionally, although successful trials have been completed [13,18], eradication success greatly depends on early detection and treatment [19].…”

“…In 1982, C. esculentus was detected for the first time in Limburg, the easternmost province of Flanders (northern part of Belgium) [2]. Since then, the species has moved in west through Flanders; it now covers an estimated agricultural area of 16,000 ha and is still spreading [3]. Cyperus esculentus is also spreading rapidly in Central Europe because of accidental introductions and subsequent expansion [4].…”

Impacts of herbicide sequences and vertical tuber distribution on the chemical control of yellow nutsedge (Cyperus esculentus L.)

“…It is on the European and Mediterranean Plant Protection Organization (EPPO) list of invasive alien species (EPPO, 2020). Cyperus esculentus is a hard to control or eradicate weed because of its high reproduction rate (reproduction factor of 1:746 and 1:638 according to Bohren and Wirth (2015) and De Cauwer et al (2017), respectively) and its low sensitivity to control measures (Bohren and Wirth, 2015;De Cauwer et al, 2017;Neuweiler and Total, 2012). Yield losses of 50% and more are common in C. esculentus infested fields (Total et al, 2018).…”

“…Small infested spots are easier to control with hand weeding and localised control methods (Bohren and Wirth, 2013). At present, curative control in Belgium is mainly based on multiple applications of herbicides in a maize (Zea mays L.) monoculture and should focus on the depletion of the bud bank, by preventing the formation of new tubers and killing the present tubers (Bohren and Wirth, 2018;De Cauwer et al, 2017;Felix et al, 2012;Keller et al, 2013;Neuweiler and Total, 2012;Stoller et al, 1972). Maize is a moderately good competitor once its canopy is closed and is the only crop in which selective herbicides with acceptable activity against C. esculentus are allowed in Belgium.…”