Efficacy of New Russian Herbicide Based on Metamitron and Ethofumesate at White Lupine

White lupin (Lupinus albus L.) is an agricultural crop that is low-income in terms of the range of herbicides allowed for use during its growing season. We studied the biological and economic effectiveness of the use of a new domestic combined herbicide Sebring SК (metamitron 350 g/l + ethofumezate 150 g/l) for seedlings of weeds in white lupine crops in the phase of cotyledons of dicotyledons and the first leaf of cereal weeds, when lupine plants formed from 2 to 4 true leaves. The studies were conducted in 3 regions of the Russian Federation: Omsk, Belgorod and Astrakhan Oblasts during 2 growing seasons of 2021–2022 in accordance with generally accepted methods of studying herbicides in the field. The accounting of weeds was carried out using the quantitative and weighting method. The greatest effectiveness of the herbicide Sebring SК was noted in the Belgorod Oblast: the use of the 2.0 l/ha preparation rate reduced the total number of weeds by 76.2%, their weight decreased by 93.2–93.9%, and the 4.0 l/ha application rates resulted in 91.1 and 97.1–97.4%, respectively. The studied drug most strongly suppressed the following types of weeds: common hemp-nettle, redroot pigweed, cleavers, and black bindweed, was effective against annual yellow woundwort and field pansy. White goosefoot and common sandbur showed average sensitivity to the studied drug. The largest yield increases in physical terms from the use of the herbicide Sebring SK were obtained in the Belgorod Oblast (Dega variety) – 4.5–5.9 c/ha. In 5 of the 6 experiments conducted, the yield increases were statistically significant: in the conditions of Omsk Oblast. (Dega variety) they ranged from 0.8 to 1.9 kg/ha, in the conditions of Astrakhan Oblast (Start variety) – 1.8–2.2 kg/ha.