Revista Brasileira De Herbicidas 2002; 3(1): 69-74
Weed control and selectivity of diclosulam as a preemergence soybean herbicide
DOI: 10.7824/rbh.v3i1.375
The present research involved two field experiments. The first one, carried out at Iguaraçu, PR, inc1uded rates of diclosularn (30,35 and 40 g1ha), imazaquin (140 g/ha), flumetsulam (108 g1ha) and a weed-free control were evaluated in a completely randomized block design with four replications. Diclosulam provided efficient control ofthe grass Pennisetum typhoideum up to 42 days after application (DAA), requiring a suplementary postemergence grass herbicide to alow suitable control at harvest. In relation to Commelina bengalensis, diclosulam at 30 g1ha provided 89% control at 63 DAA. For broadleaves like Raphanus raphanistrum and Sida rhombifolia, diclosulam provided good control (>97%) even at the lowest rate, being similar or superior in relation to imazaquin and flumetsulam at harvest. Since diclosulam alone did not provide suitable grass control until harvest, in the second experiment the mixture of diclosulam and metolachor was evaluated. Diclosulam, at 25 g/ha, alone or with metolachor (~1200 glha) provided good control (~93%) of C. benghalensis, Euphorbia heterophylla and Desmodium tortuosum, with no significant differences among evaluated combination of rates. It was not possible to evaluate the efficacy of the combined application of diclosulam and metolachor on grass weed control due to absence of infestation.
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