Investigating on the Effect of Different Herbicides on Cut-Leaf Geranium (Geranium dissectum L.) and Oilseed Rape (Brassica nappus L.) Yield in Mazandaran

To investigate the efficacy of different herbicides on cut leaf geranium (Geranium dissectum), yield and yield components of rapeseed, an experiment was carried out in a randomized complete blocks design with 10 treatments and 4 replications in Babol (Shirsavar village) in 2012,. The treatments were Metazachlor Quinmerac (Butisan Star 6.41% OSCE), pre emergence (2500 ml/ha and 3000 ml/ha), Metazachlor Quinmerac (Butisan Star 6.41% OSCE) in early growth rate (3000 ml/ha), Lontrel (Chlopyralid SC300) in early growth rate with adjuvant (1000 ml/ha) and without adjuvant (1000 ml/ha), Colzor-trio (Dimetachlor18.75% Nepropamid 18.75 % Clomazone 3%) pre emergence (3000 ml/ha and 3500 ml/ha), Tridox (Dimetachlor) pre emergence (3000 ml/ha), control (without weed control) and check control (with weed control). The results showed significant differences among the treatments (P≤0.01). After weed control, Colzor-trio (3000 ml/ha and 3500 ml/ha) had the lowest weed density and dry weight of geranium as well as the highest rapeseed dry weight. Furthermore, it had significant difference with other treatments. With regard to oilseed yield, Colzor-trio (3000 ml/ha and 3500 ml/ha) did not have significant differences with check control while it had significant differences with other treatments. Based on the results of this experiment, Colzor-trio (Dimetachlor18.75% Nepropamid 18.75 % Clomazone 3%) pre emergence (3000 ml/ha) is recommendable for control of G. dissectum in lowland oilseed rape fields.