Background Ipomea eriocarpa and Setaria virdis are widespread in maize fields in Egypt due to the recommended herbicides having less effect on one or every two species. Ipomea eriocarpa is twines on maize plants and breaks it as well as fewer pollution processes in maize, causing more damage to maize yield losses. The rotations of applied herbicides can overcome this problem, so, this work aims to evaluate the best sequence over two years for ten weed control treatments in sequence in maize fields chemical treatments with the fotowing six herbicides: Pendimethaline 45.5% CS (T1) at 3.6 l ha-1, Isoxaflutol 22.5%+Theincarbazone-methyl 9% SC Cyprosulfamide (safener) 10% SC (T2) at 360 cm3ha-1, Metribuzin 70% WG (T3) at 720 g ha-1, Foamsulfuron 3.35%+Iodosulfuron methyl-sodium 0.11%+Thiencarbazone-methyl 1.07% OD (T4) at 1200 cm3 ha-1, Foramsulfuron 2.25 OD (T5) at 1800 cm3 ha-1 and Bromoxynil 10%+Terbuthylanine 25% SE (T6) at 1200 cm3ha-1 with three hand hoeing treatment as mechanical weed control thrice (T7), twice (T8) and once (T9) and check weedy (untreated) (T10). Two field experiments were carried out at the experimental farm station, Agricultural Research Center, Giza, Egypt, during the 2021 and 2022 summer seasons in a randomized complete block design (RCBD).
Results showed that weed biomass was approximately 96 and 59.5 ton ha-1 in the 2021 and 2022 seasons, respectively, in the infested plots. The efficacy of treatments T2 and T4 were nearly equaled T8 and T9 under high infestation by Ipomea eriocarpa and Setaria vir dis during the first season, while treatments T1, T2, T4 and T5 were insignificantly different in reduced weed biomass as well as improvement maize growth, yield and its components than T8 in the second season as well as increased gross income and profitability of maize crop.
Conclusion according to the obtained results, the treatments T2, T4, T5, T1 and T7 or T8 as a rotation for two years were recommend for weed control and increased grain yield and profitability of maize.