Sulfosulfuron used for chemical control of Bromus rigidus in wheat in the Sais area of Morocco.
Field studies were conducted during 1998-99 in the Sais area (Morocco) to evaluate the efficacy of sulfosulfuron against Bromus rigidus in wheat (Triticum) subsp., and selectivity. Sulfosulfuron applied at 27 g/ha at the three leaf stage of wheat and Bromus showed the greatest efficacy on plant density and dry matter, averaging 90.7 and 95.3%, respectively. However, the highest grain yield increase was 101.7% for Oum Rbia and 95.6% for the Achtar variety. Sulfosulfuron applied at the same concentration (27 g/ha) resulted in a panicle and seed production of Bromus of 81.9 and 85% for durum wheat, and 95.6 and 83.3% for bread wheat, respectively. Metribuzin applied at 700 g a.i./ha at the beginning of tillering had good efficacy on plant density and dry matter of Bromus but 75% of wheat plants were injured. Metribuzin applied at 350 g a.i./ha twice (beginning and end of tillering) gave the best level of weed control and low phytotoxicity to durum wheat. Sulfosulfuron applied at 33 g/ha was safe for bread wheat and gave an effective level of control of Avena sterilis (87%) and Sinapis arvensis (95%). The efficacy on panicles and seed production of Bromus was 72-97% and 75-94%, respectively. Grain yield was 93-112% for durum wheat and 84-102% for bread wheat.