CLOMAZONE AND OXYFLUORFEN FOR WEED-CONTROL IN TRANSPLANTED CABBAGE (BRASSICA-OLERACEA L.)

Two field experiments were conducted in 1992-93 and 1994 at Juana Diaz , Puerto Rico, to evaluate clomazone, oxyfluorfen, and prometryn as pr eplant herbicides in cabbage. After three weeks, clomazone (1.12 and 2 .24 kg ai/ha), oxyfluorfen (0.28 and 0.56 kg ai/ha), and prometryn (2. 0 and 4.0 kg ai/ha) reduced weed density by more than 67% and 90% in 1 992-93 and 1994, respectively. At the lower rate, clomazone and oxyflu orfen caused 15% to 25% injury to cabbage when evaluated after three w eeks, and 2% to 10% after six weeks. Prometryn caused more than 65% in jury and reduced cabbage yield by more than 84%. Cabbage treated with clomazone at both rates and oxyfluorfen at 0.56 kg ai/ha produced yiel ds similar to that of the handweeded check (39,980 kg/ha) in 1992-93. Interference to cabbage was caused mostly by purple nutsedge (Cyperus rotundus L.) in 1994.