Herbicide Options for the Management of Navua Sedge (Cyperus aromaticus) Plants Established through Seeds

Abstract

Navua sedge is a difficult-to-control perennial sedge in north Australian farming systems, including fallow fields, pastures, and along roadsides and fencelines. A set of pot trials were conducted to evaluate the performance of different herbicides when used alone or in mixtures on different sizes of Navua sedge plants, and the performance of different adjuvant treatments on the rainfastness of halosulfuron-methyl. Glyphosate at 1080 g·ha−1, halosulforon-methyl at 49 g·ha−1, and paraquat at 600 g·ha−1 provided complete control of Navua sedge at the 6-leaf stage. Azimsulfuron at 20 g·ha−1 resulted in 18% and 39% survival of the 14 to 18 leaf stage and 60–70 leaf stage plants, respectively. Compared with the nontreated, this herbicide treatment suppressed plant biomass by 99.6% and 93%, respectively, and the surviving plants did not produce seed heads. A sole application of azimsulfuron, glyphosate, or halosulfuron-methyl was not effective on very large plants (140–150 leaf stage; 40–42 cm tall) of Navua sedge. However, a mixture of any two herbicides resulted in the complete control of Navua sedge. Compared with the currently used adjuvants at 0.5 to 1% concentrations, the use of non-ionic adjuvants at high concentrations (i.e., 2% ActivatorTM, HastenTM, and UptakeTM) improved the rainfastness of halosulfuron-methy when applied at 49 g·ha−1 on Navua sedge. This study identified effective herbicide treatments (e.g., azimsulfuron-based combinations) for the management of large plants of Navua sedge.

Soil macrofauna diversity and weed dynamics in response to different methods of weed control in smallholder rubber farming

“…& Kük.) (Chauhan and Mahajan 2022). The mixture herbicide glyphosate and metsulfuron-methyl in the experiment reported here has successfully controlled all weed species.…”

“…Herbicide has been the most effective mean of weed control that may reduce weeds and improve farmers' economic returns (Gage et al 2019;Langaro et al 2020;Cabrera-Pérez et al 2022;Chauhan and Mahajan 2022;Fuhrimann et al 2022). In contrast, the herbicide may have a negative impact on the environment (He et al 2019;Kwonpongsagoon et al 2021;Hong et al 2022) as well as resistance of certain weed species to herbicides such as Eleusine indica (L.) Gaertn.…”

Utilization of the Neighborhood Design to Evaluate Suitable Pasture Crops and Their Density for Navua Sedge (Cyperus aromaticus) Management

“…Therefore, farmers must consider additional costs and unintended effects on desirable plants before implementing chemical control methods. A study found that halosulfuron-methyl, glyphosate, and paraquat provided complete control (100%) of Navua sedge in small plants (6-leaf stage) but were ineffective against very large plants (140-150 leaf stage) [9]. However, surviving plants did not produce seeds, suggesting that these herbicides could manage the Navua sedge seed bank.…”

“…However, surviving plants did not produce seeds, suggesting that these herbicides could manage the Navua sedge seed bank. The current options for highly effective herbicides are limited to fallow periods or use along roadsides and fence lines, necessitating assessment of their suitability alongside other weed management options in future studies [9].…”