Weed Control J 2026; 25: e202600903
Competitive of Solanum americanum in coexistence with soybean and weed response to herbicides
DOI: 10.7824/wcj.2026;25:00903
Abstract:
Background:
Efficient management of S. americanum (Black nightshade) requires understanding its competitive behavior with soybean and the species’ sensitivity to herbicides.
Objective:
To evaluate the competitive ability of S. americanum infesting soybean and to assess potential herbicides for post-emergence control of the weed.
Methods:
Two greenhouse experiments were conducted using a completely randomized design with four replications. In the first experiment, the competitive ability of soybean was tested in the presence of different densities of S. americanum. In the second experiment, the effect of the herbicides chlorimuron-ethyl, nicosulfuron, 2,4-D amine, pyroxsulam, glyphosate, paraquat, ammonium glufosinate, carfentrazone-ethyl, imazethapyr + flumioxazin, and flumioxazin on post-emergence control of the species was studied.
Results:
The soybean cultivars BMX Ícone IPRO and DM 5958 RR showed similar competitive ability in the presence of S. americanum, with reductions in root and shoot dry biomass when infested by the weed. Increased S. americanum density caused both intra- and interspecific competition, limiting the growth of roots and shoots in both species. The herbicides glyphosate, paraquat, ammonium glufosinate, carfentrazone-ethyl, imazethapyr + flumioxazin, and flumioxazin had the greatest effect on S. americanum growth, resulting in complete plant control and the largest reductions in plant height and shoot dry biomass compared to the other products.
Conclusion:
S. americanum exhibits high competitive potential, and the herbicides glyphosate, paraquat, ammonium glufosinate, carfentrazone-ethyl, imazethapyr + flumioxazin, and flumioxazin provide 100% control of the weed.
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