Test results of the new herbicide Flex in soybean crops in Primorsky Territory

Abstract

The biological and economic efficiency of the new herbicide Flex in post-emergence application to soybean crops of the variety Sphera was studied. The tests were carried out incompliance with the standard methods in the form of the plot experiment in 2017, 2018 on brown meadow podzolized soils in the south of the Far East. The preparation was tested in the consumption rates of 1.25 and 1.5 l/ha when the crop reached the development phase of two triple leaves as opposed to the standard herbicide Galaxy Top in the rate of 1.7 l/ha. It was found that Flex has a high herbicidal activity against all dicotyledonous annual and perennial species of weeds. Common ragweed (Ambrosia artemisiifolia L.) and Asian copperleaf (Acalypha australis L.) were highly sensitive to the preparation even in the minimum consumption rate. Especially strong toxic effect of Flex was produced on such weeds in the rosette phase as Asiatic dayflower (Commelina communis L.), lamb’s quarters (Chenopodium album L.), field milk thistle (Sonchus arvensis L.), creeping thistle (Cirsium setosum (Willd.) Bieb.) and common mugwort (Artemisia vulgaris L.). Consistent application of graminicide Fuzilade Forte in the rate of 1.5 l/ha after treatment of soybean crops with herbicide Flex contributed to an almost complete elimination of annual grass weeds. The high biological efficiency of the experimental preparation contributed to a significant increase in crop yield. In 2018, when it was applied in the minimum rate of 1.25 l/ha, the yield achieved was 0.94 t/ha, exceeding the control value by 3.3 times. The highest yield increase of soybean seeds (1.12 t/ha on average for 2 years) was obtained with the use of herbicide Flex in the maximum consumption rate of 1.5 l/ha. Application of herbicide Flex to soybean crops in the rates of 1.25 and 1.5 l/ha alongside with the preparation Trend 90 in the rate of 0.2 l/ha proved to be highly effective in eliminating annual and perennial dicotyledonous weeds (in early stages of development) from soybean crops.