Assessment of selected herbicides and influence on yield of sorghum in north-eastern Poland conditions

Experiments were established on farmer's fields in the Podlasie province. They were arranged using randomized block designe with four replications. The dominant weed species were: Elymus repens, Fallopia convolvulus, Chenopodium album, Viola arvensis, Matricaria maritima ssp. Applied herbicides limited weed infestation in varying degree. The most effective herbicides against weeds in sorghum occurring crops were Lumax 537,5 SE (regardless of the date of application) and the Boreal 58 WG (regardless of the dose), which controlled the Artemisia vulgaris, Ch. album, Galeopsi tetrahit, M. maritima ssp., V. arvensis, Raphanus raphanistrum, Rumex acetosella almost in 100%. All herbicides used with the exception of pesticides Zeagran 340 SE resulted in phytotoxic effects to the sorghum crop. The highest yield of fresh mass (39.2 t/ha) was obtained from the plots, with preemergence treatment by herbicide Lumax 537,5 SE (mesotrione + terbuthylazine + S-metolachlor) at a dose of 3.5 l/ha. The average yield from the control plots was 16 t/ha. Herbicides based on: bromoxynil, terbuthylazine, mesotrione, S-metolachlor and acetochlor, florasulam and 2,4-D can be used for weed control in the cultivation of sorghum.