Evaluation of Mesosulfuron-methyl+ iodosulfuron-methyl sodium+ in control susceptible and resistant populations of Wild oat (Avena ludoviciana Durieu.) influenced by the dose and application of adjuvant

A greenhouse study was conducted during the 2019-2020 at the Plant Protection Research Institute in Tehran. A completely randomized design in factorial arrangement with four replications was used evaluate the effects of five adjuvants (first factor), different doses in conjunction with mesosulfuron-methyl+iodosulfuron-methylsodium herbicide(second factor) on the resistantandsensitive populations of wild oat to clodinafop-propargyl herbicide (third factor). At the 2 to 3 leaf stage of the wild oat, spraying was done doses of 1.05, 1.2, 1.35, 1.5 liters per hectare, with five types of additives in the amount of four, two, 0.1, 0.04 and 0.03 liters per hectare. Four weeks after spraying percentage of fresh weight, dry weight and survival of the plants were measured. In all doses, Ino Alg NPK (NG) adjuvant had the greatest effect on reducing the fresh weight of sensitive and resistant wild oat biotypes. Among the four doses of mesosulfuron-methyl+iodosulfuron-methylsodium herbicide, the doses of 1.5 and 1.05 times the recommended dose, had the highest and lowest efficacy in fresh weight loss and dry weight in sensitive and resistant populations of wild oat, respectively. According to the EWRC index data, the effectiveness of all adjuvants was the same on sensitive associations (100%) but different on resistant associations. Also, based on this index, sensitive and resistant populations in almost all doses showed almost the same percentage of control. In general, in this experiment, Ino Alg NPK (NG) adjuvant and 1.5 times the recommended dose showed the highest efficiency in controlling both susceptible and resistant populations of wild oat.