Herbicides in soybean development: productive aspects and physiological quality of seeds

The objective was to evaluate the production components of soybean and the physiological quality of seeds according to the application of subdoses of herbicides at the reproductive stage of healthy plants. The treatments consisted of the application of glyphosate (122.5 g acid equivalent [ae] ha(-1)), chlorimuron (1.75 g active ingredient [ai] ha(-1)), 2,4-D (134 g ae ha(-1)), fomesafen (60 g ai ha(-1)), glufosinate (55 g ai ha(-1)), paraquat (35 g ai ha(-1)), and control (no application). The chlorophyll index, agronomic performance, and physiological quality of seeds were evaluated. Glyphosate, chlorimuron, fomesafen, or glufosinate resulted in an increase in soybean plant height. Chlorimuron increased yield compared to the control. Paraquat or glufosinate, despite the injury, did not reduce yield, but the application of these herbicides is not recommended to stimulate plant development, given the potential for injury. The 2,4-D was the only one that caused a reduction in the physiological quality of soybean seeds.