Journal
PLANTA DANINHA
Volume 38, Issue -, Pages -Publisher
UNIV FEDERAL VICOSA
DOI: 10.1590/S0100-83582020380100023
Keywords
2,4-dichlorophenoxyacetic acid; ammonium glufosinate; Spermacoce latifolia; Spermacoce verticillata; Richardia brasiliensis
Categories
Ask authors/readers for more resources
Spermacoce latifolia, S. verticillata, and Richardia brasiliensis (family Rubiaceae, tribe Spermacoceae) are glyphosate-tolerant weeds in the soybean producing areas of Brazil. The weed shifts to glyphosate-tolerant weeds across soybean-producing areas has shown the need for adoption of practices that conserve the efficacy of glyphosate. This study evaluated the effect of single- and double-knockdown herbicide applications on the control of S. latifolia, S. verticillata, and R. brasiliensis prior to soybean sowing. Trials were designed as a randomized block and treatments were arranged as a factorial. Factor A was three systemic herbicide treatments 10 days before sowing (DBS), while Factor B was three contact herbicide treatments applied 0 DBS (sow and apply). The single- and double-knockdown applications were followed by post-emergence applications of glyphosate or 2,4-D + glyphosate when the crop reached three leaves. The efficacy of control of each weed species was visually evaluated 14 days after sowing (DAS), as well as 0 and 28 days after post-emergence application (DAA). The double-knockdown applications generally provided higher levels of control for the target weeds of the Rubiaceae family than the single-knockdown applications. Glyphosate + 2,4-D, glyphosate + 2,4-D + diclosulam or glyphosate + [halauxifen-methyl + diclosulam] followed by glufosinate or paraquat achieved at least 90% of control of S. latifolia and R. brasiliensis, but did not control S. verticillata (<80%). Glufosinate at 457 g a.i. ha(-1) was equivalent to paraquat at 400 g a.i. ha(-1) as a contact herbicide in the double-knockdown applications, especially on the first assessment dates.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available