Investigating Efficacy of New Herbichdes to Control Dodder (Cuscuta campestris) in Sugarbeet (Beta vulgaris) Fields

To investigate chemical control of dodder (Cuscuta campestrisYunk.) which is spreading insugarbeet fields, an experiment was conducted using metolachlor (commercial name Dual gold) at 1, 2, 2.5 &3 Lha-1, two formulations of propizamid (Wettable Powder: WP), commercial name Kerb and Suspension Concentrate: SC), commercial name Burst) at 1, 1.5, 2 &2.5 L/kg ha-1 and ethofumesate (commercial name Etho) 1, 1.5, 2 & 2.5 Lha-1. The experiment was performed in the Weed Research Department greenhouse, Karaj and Orumieh fields. The expermints were carried out in a randomized complete blocks design with 17 treatments and 4 replications in the greenhouse and 16 treatments with 4 replications in the fields. All dosages were sprayed at 4 leaf stages of sugarbeet and before dodder attatchment. The effect of herbicide treatments was analysed on dodder fresh and dry weight and sugarbeet yield. Greenhouse results indicated that propizamid Burst 2.5 Lha-1 as the the best herbicide treatment and caused the most decrease in dodder fresh and dry weight (93 to 99%, compared to dodder infested control), and also the most increase in sugarbeet shoot fresh and dry weight (51 to 94%) with Rasool cultivar. Based on field studies, propizamid Burst 2 to 2.5 Lha-1 and ethofumesate 2.5 Lha-1 were the best treatments. As SC formulation is safer and easier to apply than WP formulation, propizamid Burst 2 to 2.5 Lha-1 and ethofumesate 2.5 Lha-1 are recommended for dodder control in sugarbeet.