Efficiency of herbicide Acris (dimethenamid-P + terbuthylazine) on sunflower

Trials with a herbicide Acris, SE (280 g/l of dimethenamid-P + 250 g/l of terbuthylazine) were carried out in the Astrakhan, Krasnodar and Altai regions. The aim of this work is studying biological and economic efficiency of pre-emergence treatment with the combined herbicide Acris, SE on sunflower. The treatment with the herbicide Acris, SE (2.0-3.0 l/ha) made it possible to prevent many annual dicotyledonous weeds: Chenopodium album, Amaranthus retroflexus, Fagopyrum tataricum, Abutilon theophrastii and Solanum nigrum. Ambrosia artemisiifolia, found in the Krasnodar region, is less sensitive to this herbicide. The herbicide Acris, SE was highly effective in suppressing annual monocoty- ledonous weeds: Echinochloa crusgalli and Panicum miliaceum. Efficiency of the herbicide ACRIS was at the level of the standard Gardo Gold, and at the maximum application rate (3.0 l/ha) exceeded the standard one. Preemergence soil treatment with the herbicide Acris, SE did not have a negative effect on the germination of sunflower. Significant increase of sunflower yield was noted in all regions of trials. The most significant values were observed on varieties Flagman and R 453 in the Krasnodar region (8.7-9.2 and 7.0-7.5 quintal/ha, respectively). The lowest yields of sunflower in untreated control (10.2 and 11.0 quintal/ha) were observed in the Altai region, but the relative increase in yield in variants with the herbicide Acris, SE application was maximum (from 29.1 to 67.6% in relation to yields in untreated control). In the Astrakhan region, application rates of the herbicide Acris, SE of 2.5 and 3.0 l/ha were characterized by statistical significance (increases up to 2.5 and 3.2 quintal/ha, respectively).