Weed control in melon with preemergence herbicides

Abstract

The objective of this work was to evaluate the effectiveness and selectivity of herbicides applied at preemergence to the melon (Cucumis melo) crop. The experiments were carried out from 2017 to 2018, in a randomized complete block design, with four replicates, in the state of Rio Grande do Norte, Brazil. The treatments consisted of the preemergence application of: 35 g ha-1 a.i. flumioxazin, 25 g ha-1 a.i. flumioxazin, 250 g ha-1 a.i. sulfentrazone, 480 g ha-1 a.i. metribuzin, 240 g ha-1 a.i. oxyfluorfen, 240 g ha-1 a.i. oxyfluorfen + 960 g ha-1 a.i. S-metolachlor, 360 g ha-1 a.i. clomazone, and 360 g ha-1 a.i. clomazone + 240 g ha-1 a.i. oxyfluorfen; in 2018, metribuzin did not show selectivity and was substituted by 480 g ha-1 a.i. ametryn and 1,600 g ha-1 a.i. diuron. Fruit yield and quality, as well as weed control and dry mass, were evaluated. The metribuzin, ametryn, and diuron herbicides caused melon plant death. The best efficiency in weed control was obtained with the mixture clomazone + oxyfluorfen, followed by oxyfluorfen, oxyfluorfen + S-metolachlor, and clomazone. The treatments with oxyfluorfen, oxyfluorfen + S-metolachlor, and clomazone + oxyfluorfen were not considered selective. Clomazone was the only selective herbicide in the two years of evaluation and can be an alternative for weed control in melon crops.

Herbicide screening for weed control and crop safety in California melon production

“…The use of nonchemical weed control methods, such as cover crops (Kosterna 2014; Monday et al 2015; Wang et al 2008) and soil solarization (Ozores-Hampton et al 2012; Reddy 2013), may not provide many growers with sufficient economic returns (Wang et al 2009). Herbicides available for use in cucurbits, which are relatively limited in number, often have a narrow control spectrum and lower overall rate ranges to ensure crop safety (Brandenberger et al 2005; Carvalho et al 2022; Figueroa and Kogan 2005; Grey et al 2000; Johnson and Mullinix 2005; Norsworthy and Meister 2007; Webster and Culpepper 2005). Consequently, there is a need to screen additional herbicides for potential use in California melon production.…”