RESPONSE OF SOYBEAN (GLYCINE-MAX) AND RICE (ORYZA-SATIVA) IN ROTATIONTO AC-263,222

Field studies were conducted in 1991 and 1992 to evaluate the response of soybean and the subsequent rice crop to AC 263,222 applied alone a nd in tank mixtures with imazethapyr or imazaquin. In 1991, 18, 36, an d 70 g ai/ha of AC 263,222 visibly stunted soybean 9, 19, and 35%, res pectively. Adding imazethapyr at 36 g/ha or imazaquin at 70 g/ha to AC 263,222 in a tank mixture did not increase soybean response compared to AC 263,222 alone. Soybean yield was not reduced by any treatment. I n 1992, 14 g/ha of AC 263,222 alone or in tank mixtures damaged soybea n 38% or greater. In one study, rice was injured the year following ap plication of AC 263,222 alone and in tank mixtures. Rice yield was red uced by 70 g/ha of AC 263,222 alone and by 36 g/ha of AC 263,222 when tank mixed with 36 g/ha of imazethapyr.