Broomrape (Phelipanche ramosa (L.) Pomel) Control in Winter Oilseed Rape with Imazamox-Containing Herbicide Products

The broomrapes are root, obligate parasites without chlorophyll. They parasitize mostly the dicotyledonous plants. Phelipanche ramosa (L.) Pomel attacks a wider range of hosts among which is the winter oilseed rape (Brassica napus L.). The broomrape can reduce the yields and aggravate the quality of production. There are few effective measures to control this parasite. One of the most promising approaches is the cultivation of Clearfield® oilseed rape and the treatment of imazamox-containing herbicide products. For this purpose during the growing seasons of 2016 - 2017 and 2017 - 2018 a field pot experiment with the Clearfield® oilseed rape hybrid РТ 228 CL was conducted. The soil of the field pots was artificially infested with Ph. ramosa seeds. The herbicide application was performed in two stages of the crop in the spring - BBCH 31–33 (1-3 internodes visible) and BBCH 51 („green button“). Variants of the trial were: 1. Untreated control; 2. Cleranda® (375 g/l metazachlor + 17,5 g/l imazamox) – 2,00 l/ha (BBCH 31–33); 3. Cleravo® (250 g/l quinmerac + 35 g/l imazamox) – 1,00 l/ha (BBCH 31–33); 4. Pulsar® Plus (25 g/l imazamox) – 1,00 l/ha (BBCH 31–33); 5. Pulsar® Plus – 2,00 l/ha (BBCH 31–33); 6. Pulsar® Plus – 0,50 l/ha (BBCH 51); 7. Pulsar® Plus – 1,00 l/ha (BBCH 51); 8. Pulsar® Plus – 2,00 l/ha (BBCH 51). Average for both years of the study, the highest efficacy against the parasite after the application of Pulsar® Plus – 2,00 l/ha (BBCH 51) – 92,9% followed by Cleranda® – 2,00 l/ha (BBCH 31–33) - 91,2% was reported.