The purpose of the article is to study the scientific activity and assets of one of the scientists of the Institute of Plant Protection of the National Academy of Agrarian Sciences of Ukraine – Doctor of Agricultural Sciences, Professor Sekun Mycola Pavlovych. The source base is materials devoted to the activities of M. P. Sekun, as well as scientific works of the scientist. It was established that 57 years of M. P. Sekun's life were devoted to the development of domestic agricultural science. For 47 years, his scientific activity was associated with the Institute of Plant Protection of the National Academy of Agrarian Sciences of Ukraine. M. P. Sekun scientifically substantiated the system of chemical protection of winter wheat from pests. Much has been done for the in-depth study of the impact of pesticides on the specifics of the development of harmful and beneficial arthropods. The characteristics of the resistance of populations of pests of agricultural crops to pesticides are given. The ability of some insecticides to show moderate selectivity towards some beneficial arthropods has been revealed. A system of measures has been developed to protect agricultural lands from locusts, fruit plantations of the Piedmont Crimea from leafhoppers, seed clover crops, rapeseed crops, medicinal labium crops, and grain stocks from a complex of pests. Prospective directions of research on agronomic toxicology have been identified. M. P. Sekun is the author of about 300 published scientific works. He created a scientific school.

Professor M. P. Sekun made a significant contribution to the development of agricultural entomology and toxicology and, at the same time, to the successful solution of problems of plant protection from pests. Scientifically based systems of chemical protection of winter wheat and other crops from pests and greening of plant protection in general are his important scientific achievements. This is the basis for the development and successful functioning of a biological method of plant protection.

1. Trybel’, S. O. (2000). Zakhyst roslyn: sohodni i zavtra [Plant protection: today and tomorrow]. Zakhyst roslyn, no. 2, pp. 2–4 [in Ukrainian].
2. Chaika, V. M., Siadrysta, O. B., Baklanova, O. V., & Melnyk, P. P. (2001). Shkodochynnist fitofahiv na ozymyni [Harmfulness of phytophages in winter wheat]. Zakhyst roslyn, no. 12, pp. 1–2 [in Ukrainian].
3. Sekun, N. P. (1968). Nekotorye fiziologicheskie izmeneniya u cheshuekrylykh pri kishechnom otravlenii insektitsidami [Some Physiological Changes in Lepidoptera During Intestinal Insecticide Poisoning]. Entomologicheskoe obozrenie, vol. XLVII, no. 4, pp. 726–730 [in Russian].
4. Sekun, N. P. (1969). Vliyanie insektitsidov na aktivnost' pishchevaritel'nykh fermentov nasekomykh [Effect of insecticides on the activity of insect digestive enzymes]. Khimiya v sel'skom khozyaystve, no. 5, pp. 40–42 [in Russian].
5. Krut’, M. V. (2021). Do 75-richchia Instytutu zakhystu roslyn NAAN Ukrainy. Entomolohichni shkoly [To the 75th anniversary of the Institute of Plant Protection of the NAAS of Ukraine. Entomological schools]. Ukrainskyi entomolohichnyi zhurnal, no. 1–2, pp. 85–101 [in Ukrainian].
6. Sekun, M. P. (1996). Toksychnist insektytsydiv i temperatura seredovyshcha [Insecticide toxicity and environmental temperature]. Zakhyst roslyn, no. 6, p. 8 [in Ukrainian].
7. Sekun, N. P., Nekhay, A. S., & Krasyukova, Ya. F. (1994). Raskhod insektitsidov nuzhno differentsirovat' [Insecticide consumption needs to be differentiated]. Zashchita rasteniy, no. 3, p. 15 [in Russian].
8. Areshnikov, B. A., Sekun, N. P., Assaul, B. D., Kostyukovskiy, M. G., Feshchin, D. M., & Izzadin, D. M. (1984). Effektivnost' predposevnoy obrabotki semyan ozimoy pshenitsy insektitsidami protiv khlebnoy zhuzhelitsy [Efficiency of presowing treatment of winter wheat seeds with insecticides against ground beetles]. Zashchita rasteniy. Kiev: Urozhay, vol. 31, pp. 21-25 [in Russian].
9. Sekun, N. P., Kudel', K. A., Satsyuk, O. S., Mel'nikova, G. L., Zil'bermints, I. V., & Zhuravleva, L. M. (1990). K izucheniyu potentsial'noy ustoychivosti zlakovykh tley k insektitsidam [To study the potential resistance of cereal aphids to insecticides]. Zashchita rasteniy. Kiev: Urozhay, vol. 37, pp. 49–53 [in Russian].
10. Sekun, N. P. (2000). Problemy rezistentnosti vrednykh organizmov k pestitsidam [Problems of pest resistance to pesticides]. Visnyk ahrarnoi nauky, no. 1, pp. 19–21 [in Russian].
11. Sekun, N. P. (2003). Kak obstoyat dela na Ukraine [How are things in Ukraine]. Zashchita i karantin rasteniy, no. 5, pp. 14–15 [in Russian].
12. Manko, O. V., Vlasova, O. H., & Sekun, M. P. (1996). Chutlyvist plodovykh klishchiv do insektoakarytsydiv [Sensitivity of fruit mites to insectoacaricides]. Zakhyst roslyn. Kyiv: Ahrarna nauka, vol. 43, pp. 88–91 [in Ukrainian].
13. Sekun, M. P. (2004). Toksykolohiia suchasnykh insektytsydiv ta yii problemy [Toxicology of modern insecticides and its problems]. Zakhyst i karantyn roslyn. Kyiv : Kolobih, vol. 50, pp. 68–75 [in Ukrainian].