A field research was conducted to evaluate the effects of dinitramine and diuron mixtures on weed control in cotton at two experiments at Casa Branca - SP on a clay soil (3 ,6% organic matter) and Jaboticabal - SP on a clay loam (2,3% organic matter). The cotton variety sowed was IAC-13 -1 at Casa Branca (nov, 05, 1975) and RM-4A at Jaboticabal (dec. 3, 1975). The experiment had a design of randomized blocks with the treatments dinitramine at 0.25 kg; 0.40 kg; 0.50 kg/ha; diuron at 1.20 kg; 1.50 kg; 1.80 kg/ha and ali dinitramine + diuron mixture s with this rates; one treatment with trifluralin + diuron at 1.00 + 1.20 kg/ha, and one hoeded treatment. The best weed control results on the clay soil were obta ined by the mixtures when compared with the dinitramine and diuron appl ication on large crabgrass (Digitaria sanguinallis (L.) Scop.), go ose gras s (Eleusine indica (L .) Gaertn.), Paraguay starbur (Acanthospermum australe ( Loef.) O. Kuntze), Borreria alata (Aubl. ) D.C., Brasil callalily (Richardia brasiliensis Gomez) and sidas (Sida spp.) but on the clay loam soil were the most important weeds we re la r ge c rabg ras s , s outhe rn s andbur (Cenchrus echinatus L.) , West Indies pennisetum (Pennisetum setosum (L.) Rich. Pers), Paraguay sandbur, Brasil callalily and sidas the be st weed control results were obtained with trifluralin + diuron and with dinitramine at 0.25 kg; 0.40 kg; 0.50 kg in mixture with diuron at 1.80 kg/ha. The treatments used didn't present any phyto toxicity to cotton at the initial development and there wasn't significant difference in the total yield.
dinitramine; diuron; mixtures; cotton; weed control