Soybean yield response to control of Brachiaria plantaginea and Acanthospermum hispidum.
The results are given of trials carried out in soybeans on a deep, red latisol at Parana, Brazil. Brachiaria plantaginea caused severe reductions in the yield of soybeans. Trifluralin and pendimethalin at high rates were more selective than other herbicides incorporated before sowing, while diclofop and BAS 9024(1H)[?] applied post-em. overall and glyphosate applied as a directed, post-em. spray gave 90 to 100% control. Infestations of Acanthospermum hispidum varied according to weather conditions and competition from other weeds. Most of the loss in soybean yield was attributable to interference at harvest time.