Effectiveness of insecticide protection of maize hybrids against a complex of pests in the conditions of the Northern Steppe zone of Ukraine

Abstract

The article presents data from a study of the use of 6 pesticides and 1 plant growth regulator to minimize losses from a complex of soil pests of corn hybrids and increase yield in the conditions of the Northern Steppe zone of Ukraine. Due to the high potential productivity of new corn hybrids (LG 30215, LG 3350, DKS 3939), vigorous initial growth, and the ability of the root system to grow rapidly, high tolerance to damage, there is a loss of their yield (formation of a smaller cob size and its graininess) due to the influence of harmful organisms. The use of insecticidal sprays leads to a significant crop protection (from soil pests and seedling pests) by increasing plant density during germination (by 21.4 %) and before harvesting (by 21.5 %) and achieving programmed plant density in the corn agrophytocenoses. The faunal composition of corn pests at an early stage (against the natural background of the pest population) was detailed and clarified, and their impact on productivity during pre-sowing seed treatment with insecticidal pesticides was investigated. After seed treatment with Nominal Ultra, TN (thiamethoxicam, 350 g/l), Lord, VG (imidacloprid, 700 g/kg), Coyote, KS (imidacloprid, 600 g/l), Klops, ZP (imidacloprid, 700 g/kg), Inset, VG (imidacloprid, 700 g/kg), Valabi Protect, TN (clothianidin, 600 g/l) affected the number of soil phytophagous insects (by reducing the number of larvae to 2.0‒1.4 individuals/m2 in all variants relative to the control (untreated seeds – 8.0 individuals/m2)), which allowed us to provide an objective assessment of the effectiveness of protecting seedlings and young corn plants. Toxication of seeds of the LG 30215 corn hybrid with pesticides provided a reduction in damage to young plants by larvae of soil phytophagous insects by 15.2‒16.2 %, an increase in yield by 1.09‒1.19 t/ha.