Effectiveness of sowing methods and certain herbicides against dodder and annual weeds associated with flax

Abstract

Two field experiments were conducted during 2019/20 and 2020/21 seasons to evaluate the influence of two sowing methods (broadcasting and drilling) and nine herbicides on dodder (Cuscuta epilinum), annual weeds and the productivity of flax (Linum usitatissimum L.). Economic evaluation of the interaction between sowing methods and weed control methods was also assessed. The application sequences of nine herbicides in six treatments included tribenuron-methyl 75% DF (Aonostar 75 DF) followed by fluazifop-p-butyl, 12.5% EC (Fusilade super 12.5% EC) (T1), tribenuron-methyl, 75% WG (Zinostar 75% WG) followed by (Fusilade super) (T2), bromoxynil octaoate, 24% EC (Brominal 24% EC) followed by clodinafop propargyl 2.5% + pinoxaden 2.5% (Traksos 5% EC) (T3), bromoxynil octanoate, 24% EC (Bromo plus 24% EC) followed by clodinafop propargyl 2.5% + pinoxaden 2.5% (Traksos) (T4), florasulam 7.5% + flumetsulam10% (Derby 17.5% SC) 17.5% SC followed by clethodim 12.5% EC (Select super 12.5% EC) (T5) and dicamba, 48% SL (Dimo up 48% SL) followed by (Select super) (T6). The herbicide treatments were compared to hand weeding (twice) (T7) and unweeded control (T8). The obtained results revealed that seed drilling method increased straw, seed, fiber and oil yield in both seasons, compared to broadcasting method. Herbicide treatments of T5, T6, T1 and T2, T3 and T4 decreased dry weight of dodder and annual weeds 90 days after application, in both seasons, as compared to unweeded control. The result suggested that seed drilling method combined with the herbicidal treatments of T5, T6, T1 and T2 were greatly effective against heavily infestation with dodder and total annual weeds. These practices reflected on greater fiber, oil seed yield and higher economic profit.