Research and scientific work on the creation of hemp varieties (Cannabis sativa L.) with a reduced content of the psychotropic (narcotic) compound tetrahydrocannabinol (THC), analogues of which did not exist in breeding practice, was officially started for the first time in the world in the 70s of the 20th century in Ukraine (Institute of Bast Crops of NAAS). As a result, it was possible to reduce the THC content to 0.000% (complete absence), i.e. more than 1000 times, due to which the attitude towards hemp has radically changed in the world, in many countries the prohibitions on cultivation have been lifted, they are considered as a normal agricultural crop, and hemp growing has been preserved as a traditional branch of economy.

Reproduction of a complete picture of the development of scientific research on the elimination of the psychotropic properties of hemp by breeding means at the initial stage of work in Ukraine in 1971–1980 and the analysis of the theoretical and practical contribution of scientists of Institute of Bast Crops of NAAS to this process are the goal of this article.

Due to the application of general scientific, interdisciplinary and special scientific-historical and source studies methods, it was possible to establish the following. The study of the influence of both environmental (ecological-geographical, climatic and agrotechnical) and genetic factors (implementation of the hereditary program in the phenotype), adaptation of methods of identification of cannabinoid compounds, and practical breeding were on the list of tasks for scientists. Thin-layer chromatography was the main method of identification of cannabinoid compounds, and family-group selection and intervarietal hybridization followed by stabilizing selection were main breeding methods. USO 19, USO 28, USO 14 and USO 16 were the first monoecious hemp varieties with reduced THC content created at the Institute of Bast Crops of NAAS.

The most important contribution to reducing the psychotropic properties of hemp in 1971–1980 was made by H. I. Senchenko as the scientific leader of the research tasks, L. M. Horshkova, M. M. Sazhko, V. P. Soroka, K. I. Borodina et al. as researchers of the biological basis of the functioning of cannabinoid compounds in the plant organism and methods of their identification for breeding purposes, V. H. Vyrovets, I. I. Shcherban et al. as breeders.

1. Bazyl', S. M. (2020). Naukovo-tekhnichnyy potentsial vyrobnytstva ta pervynnoyi pererobky lub’yanykh kul'tur v URSR u druhiy polovyni 1940-kh – 1980-kh rokakh: dys. doktora filosofiyi z haluzi znan' za spets. 032 – Istoriya ta arkheolohiya [Scientific and technical potential of production and primary processing of bast crops in the Ukrainian SSR in the second half of the 1940s – 1980s: Thesis for a Doctor of Philosophy Degree by specialty 032 – History and archaeology]. Hlukhiv, Kyyiv [in Ukrainian].
2. Verhunov, V. A., & Skorchenko, S. B. (2002). Konoplyarstvo v Ukrayini: Istorychni aspekty rozvytku. Pohlyad u mynule. Problemy s'ohodennya. Perspektyvy [Hemp growing in Ukraine: Historical aspects of development. A look into the past. Today's problems. Perspectives]. Kyiv [in Ukrainian].
3. Verhunov, V. (2017). Vid nenarkotychnykh posivnykh do novykh medychnykh konopel' toruyut' shlyakh ukrayins'ki selektsionery [Ukrainian breeders pave the way from non-narcotic seeds to new medical hemp]. Svitohlyad – Ideology, no. 5 (67), pp. 39–45 [in Ukrainian].
4. Vyrovets, V. H., Senchenko, H. Y., & Shcherban', Y. Y. (1977). Mezhsortovaya hybrydyzatsyya – osnovnoy metod sozdanyya sortov odnodomnoy konoply [Intervarietal hybridization is the main method of creating monoecious hemp varieties]. Byolohyya, vozdelyvanye y pervychnaya obrabotka konoply y kenafa – Biology, Cultivation and Primary Processing of Hemp and Kenaf, issue 40, pp. 3–12 [in Russian].
5. Vyrovets, V. H. (1992). Sozdanye vysokoproduktyvnykh sortov konoply, ne obladaiushchykh narkotycheskoi aktyvnostiu: avtoref. dyss. na soyskanye uchen. stepeny dokt. s.-kh. nauk: spets. 06.01.05 «Selektsyia y semenovodstvo» [Creation of highly productive varieties of hemp that do not possess narcotic activity: Thesis for a Doctor of Agricultural Sciences Degree by specialty 06.01.05 "Plant breeding and Seed Growing"]. Kyev [in Russian].
6. Vyrovets, V. H. (2015). Selektsyia nenarkotycheskoi posevnoi konoply [Breeding of non-narcotic hemp]. Sumy [in Russian].
7. Holoborod'ko, P. A. (Eds.). (2007). Vyrovets' Vyacheslav Havrylovych: bibliohrafichnyy pokazhchyk [Vyrovets Vyacheslav Gavrylovich: bibliographic index]. Sumy [in Ukrainian].
8. Horshkova, L. M., & Borodyna, E. Y. (1977). Kharakterystyka novykh sortov konoply po soderzhanyyu tetrahydrokannabynola [Characteristics of new varieties of hemp according to the content of tetrahydrocannabinol]. Byolohyya, vozdelyvanye y pervychnaya obrabotka konoply y kenafa – Biology, Cultivation and Primary Processing of Hemp and Kenaf, issue 40, pp. 23–28 [in Russian].
9. Horshkova, L. M., & Borodyna, E. Y. (1978). Kharakterystyka sortov konoply kollektsyonnoho pytomnyka po soderzhanyyu tetrahydrokannabynola [Characteristics of hemp varieties of the collection nursery according to the content of tetrahydrocannabinol]. Byolohyya, vozdelyvanye y pervychnaya obrabotka konoply y kenafa – Biology, Cultivation and Primary Processing of Hemp and Kenaf, issue 41, pp. 35–41 [in Russian].
10. Horshkova, L. M., Vyrovets, V. H., Sytnyk, V. P., & Shcherban', Y. Y. (1980). Novye sorta odnodomnoy konoply [New varieties of monoecious hemp]. Len y konoplya – Flax and Hemp, no. 6, pp. 28–29 [in Russian].
11. Horshkova, L. M. (1994). Biolohichni osnovy formuvannya kannabinoyidnykh spoluk konopel' ta rozrobka metodiv vyznachennya yikh vmistu v selektsiynykh tsilyakh: avtoref. dys. na zdobuttya nauk. stupenya dokt. s.-h. nauk: spets. 06.01.05 «Selektsiya i nasinnytstvo» [Biological bases of the formation of cannabinoid compounds of hemp and development of methods for determining their content for breeding purposes: Thesis for a Doctor of Agricultural Sciences Degree by specialty 06.01.05 "Plant breeding and Seed Growing"]. Kyiv [in Ukrainian].
12. Horshkova, L. M. (2007). Kannabis [Cannabis]. (Vols. I). Hlukhiv [in Ukrainian].
13. Horshkova, L. M. (2008). Kannabis [Cannabis]. (Vols. II). Hlukhiv [in Ukrainian].
14. Holoborod'ko, P. A. (Eds.). (2008). Horshkova Lidiya Mykhaylivna: bibliohrafichnyy pokazhchyk [Horshkova Lidia Mykhailivna: bibliographical index]. Sumy [in Ukrainian].
15. Layko, I. M. (2012). Teoretychni i praktychni osnovy selektsiyi zakriplennya odnodomnosti, eliminatsiyi kanabinoyidiv ta pidvyshchennya produktyvnosti konopel': avtoref. dys. na zdobuttya nauk. stupenya dokt. s.-h. nauk: spets. 06.01.05 «Selektsiya i nasinnytstvo» [Theoretical and practical basis of breeding for monoeciousness, elimination of cannabinoids and increase in productivity of hemp: Thesis for a Doctor of Agricultural Sciences Degree by specialty 06.01.05 "Plant breeding and Seed Growing"]. Kharkiv [in Ukrainian].
16. Myhal', M. D., Kmets', I. L., & Layko, I. M. (2017). Trykhomy i kanabinoyidy konopel'. Do teoriyi selektsiyi nenarkotychnykh sortiv [Trichomes and cannabinoids of hemp. To the theory of selection of non-narcotic varieties]. Sumy [in Ukrainian].
17. (1974). Polnyi nauchnyi otchet laboratoryy selektsyy za 1973 hod po teme № 2 «Yzuchenye kannabynoydnykh soedynenyi v rastenyiakh konoply s tseliu vyvedenyia sortov, ne soderzhashchykh tetrahydrokannabynola» [Complete scientific report of the selection laboratory for 1973 on topic No. 2 "Study of cannabinoid compounds in hemp plants with the aim of breeding varieties that do not contain tetrahydrocannabinol"]. Vidomchyi arkhiv Instytutu lubianykh kultur NAAN – Departmental Archive of the Institute of Bast Crops of NAAS. Glukhov [in Russian].
18. (1974). Polnyi nauchnyi otchet za 1974 hod po teme № 2 «Yzuchenye kannabynoydnykh soedynenyi v rastenyiakh konoply s tseliu vyvedenyia sortov, ne soderzhashchykh tetrahydrokannabynol» [Complete scientific report for 1974 on topic No. 2 "Study of cannabinoid compounds in hemp plants with the aim of breeding varieties that do not contain tetrahydrocannabinol"]. Vidomchyi arkhiv Instytutu lubianykh kultur NAAN – Departmental Archive of the Institute of Bast Crops of NAAS. Glukhov [in Russian].
19. (1976). Polnyi nauchnyi otchet za 1975 hod po probleme 0407. Tema 2 «Yzuchenye kannabynoydnykh soedynenyi v rastenyiakh konoply s tseliu vyvedenyia sortov, ne soderzhashchykh tetrahydrokannabynola» [Full scientific report for 1975 on problem 0407. Topic 2 "Study of cannabinoid compounds in hemp plants with the aim of breeding varieties that do not contain tetrahydrocannabinol"]. Vidomchyi arkhiv Instytutu lubianykh kultur NAAN – Departmental Archive of the Institute of Bast Crops of NAAS. Glukhov [in Russian].
20. (1977). Polnyi nauchnyi otchet za 1976 hod po probleme 0407. Tema 2 «Yzuchenye kannabynoydnykh soedynenyi v rastenyiakh konoply s tseliu vyvedenyia sortov, ne soderzhashchykh tetrahydrokannabynola» [Full scientific report for 1976 on problem 0407. Topic 2 "Study of cannabinoid compounds in hemp plants with the aim of breeding varieties that do not contain tetrahydrocannabinol"]. Vidomchyi arkhiv Instytutu lubianykh kultur NAAN – Departmental Archive of the Institute of Bast Crops of NAAS. Glukhov [in Russian].
21. (1978). Polnyi nauchnyi otchet laboratoryy selektsyy za 1977 hod po probleme 04.11 «Sozdat vysokourozhainye sorta y hybrydy odnodomnoi konoply s urozhainostiu volokna 15–18 ts, semian 10–12 ts s 1 ha y soderzhanyem volokna 25–30%, usovershenstvovat metody y pryemy selektsyy, semenovodstva y semenovedenyia» [Complete scientific report of the breeding laboratory for 1977 on problem 04.11 "Create high-yielding varieties and hybrids of monoecious hemp with a yield of 15–18 tons of fiber, 10–12 tons of seeds per 1 ha and a fiber content of 25–30%, improve methods of breeding, seed growing and seed science"]. Vidomchyi arkhiv Instytutu lubianykh kultur NAAN – Departmental Archive of the Institute of Bast Crops of NAAS. Glukhov [in Russian].
22. (1979). Polnyi nauchnyi otchet laboratoryy selektsyy za 1978 hod po probleme 04.11 «Sozdat vysokourozhainыe sorta y hybrydy odnodomnoi konoply s urozhainostiu volokna 15–18 ts, semian 10–12 ts s 1 ha y soderzhanyem volokna 25–30%, usovershenstvovat metody y pryemy selektsyy, semenovodstva y semenovedenyia» [Complete scientific report of the breeding laboratory for 1978 on problem 04.11 "Create high-yielding varieties and hybrids of monoecious hemp with a yield of 15–18 tons of fiber, 10–12 tons of seeds per 1 ha and a fiber content of 25–30%, improve methods of breeding, seed growing and seed science"]. Vidomchyi arkhiv Instytutu lubianykh kultur NAAN – Departmental Archive of the Institute of Bast Crops of NAAS. Glukhov [in Russian].
23. (1980). Polnyi nauchnyi otchet laboratoryy selektsyy za 1979 hod po probleme 04.11 «Sozdat vysokourozhainye sorta y hybrydy odnodomnoi konoply s urozhainostiu volokna 15–18 ts, semian 10–12 ts s 1 ha y soderzhanyem volokna 25–30%, usovershenstvovat metody y pryemy selektsyy, semenovodstva y semenovedenyia» [Complete scientific report of the breeding laboratory for 1979 on problem 04.11 "Create high-yielding varieties and hybrids of monoecious hemp with a yield of 15–18 tons of fiber, 10–12 tons of seeds per 1 ha and a fiber content of 25–30%, improve methods of breeding, seed growing and seed science"]. Vidomchyi arkhiv Instytutu lubianykh kultur NAAN – Departmental Archive of the Institute of Bast Crops of NAAS. Glukhov [in Russian].
24. (1981). Polnyi nauchnyi otchet laboratoryy selektsyy za 1980 hod po probleme 04.11 «Sozdat vysokourozhainye sorta y hybrydy odnodomnoi konoply s urozhainostiu volokna 15–18 ts, semian 10–12 ts s 1 ha y soderzhanyem volokna 25–30%, usovershenstvovat metody y pryemy selektsyy, semenovodstva y semenovedenyia» [Complete scientific report of the breeding laboratory for 1980 on problem 04.11 "Create high-yielding varieties and hybrids of monoecious hemp with a yield of 15–18 tons of fiber, 10–12 tons of seeds per 1 ha and a fiber content of 25–30%, improve methods of breeding, seed growing and seed science"]. Vidomchyi arkhiv Instytutu lubianykh kultur NAAN – Departmental Archive of the Institute of Bast Crops of NAAS. Glukhov [in Russian].
25. (1985). Polnyi nauchnyi otchet laboratoryy selektsyy y henetyky za 1984 hod po zadanyiu 01 «Usovershenstvovat sushchestvuiushchye y razrabotat novye metody selektsyy y na ykh osnove vyvesty skorospelыe sorta y hybrydy odnodomnoi konoply, ustoichyvye k vredyteliam y bolezniam, prevyshaiushchye po urozhaiu volokna y semian raionyrovannye sorta, s otsutstvyem yly mynymalnym soderzhanyem tetrahydrokannabynola (THK)» [Complete scientific report of the laboratory of selection and genetics for 1984 on task 01 "Improve existing and develop new methods of selection and, on their basis, breed early-maturing varieties and hybrids of monoecious hemp, resistant to pests and diseases, exceeding regionalized varieties in terms of fiber and seed yield, with the absence or minimal content of tetrahydrocannabinol (THC)"]. Vidomchyi arkhiv Instytutu lubianykh kultur NAAN – Departmental Archive of the Institute of Bast Crops of NAAS. Glukhov [in Russian].
26. Vergunov, V. A. (Eds.). (2019). Profesor Vyrovets' Vyacheslav Havrylovych (Miy shlyakh v nautsi): biobibliohr. pokazhch. nauk. pr. za 1969–2018 roky [Professor Vyrovets Vyacheslav Havrylovich (My path in science): biobibliographic index of scientific works for the years 1969–2018]. Kyiv [in Ukrainian].
27. Senchenko, H. Y., Vyrovets, V. H., & Horshkova, L. M. (1975). K metodyke opredelenyya soderzhanyya kannabynoydov v konople [On the method of determining the content of cannabinoids in hemp]. Byolohyya, vozdelyvanye y pervychnaya obrabotka konoply y kenafa – Biology, Cultivation and Primary Processing of Hemp and Kenaf, issue 38, pp. 39–44 [in Russian].
28. Senchenko, H. Y., & Horshkova, L. M. (1976). Perspektyvy selektsyy na snyzhenye narkotycheskykh svoystv konoply [Prospects of selection for reducing the narcotic properties of hemp]. Byolohyya, vozdelyvanye y pervychnaya obrabotka konoply y kenafa – Biology, Cultivation and Primary Processing of Hemp and Kenaf, issue 39, pp. 27–33 [in Russian].
29. Senchenko, H. Y., & Horshkova, L. M. (1977). K voprosu yzuchenyya nasledovanyya kannabynoydnykh soedynenyy v konople [To the question of studying the inheritance of cannabinoid compounds in hemp]. Byolohyya, vozdelyvanye y pervychnaya obrabotka konoply y kenafa – Biology, Cultivation and Primary Processing of Hemp and Kenaf, issue 40, pp. 18–23 [in Russian].
30. Senchenko, H. Y., & Vyrovets, V. H. (1977). Yspol'zovanye myrovoy kollektsyy konoply v tselyakh selektsyy [Use of the world cannabis collection for breeding purposes]. Byulleten' Vsesoyuznoho ynstytuta rastenyevodstva – Bulletin of the All-Union Institute of Plant Industry, pp. 19–23 [in Russian].
31. Senchenko, H. Y., & Vyrovets, V. H. (1978). Osnovnye ytohy selektsyoonoy raboty po konople [The main results of hemp breeding work]. Byolohyya, vozdelyvanye y pervychnaya obrabotka konoply y kenafa – Biology, Cultivation and Primary Processing of Hemp and Kenaf, issue 41, pp. 3–12 [in Russian].
32. Senchenko, H. Y., & Horshkova, L. M. (1978). Vlyyanye ekolohycheskykh uslovyy vyrashchyvanyya na soderzhanye tetrahydrokannabynola u konoply [Influence of ecological conditions of cultivation on the content of tetrahydrocannabinol in hemp]. Byolohyya, vozdelyvanye y pervychnaya obrabotka konoply y kenafa – Biology, Cultivation and Primary Processing of Hemp and Kenaf, issue 41, pp. 17–24 [in Russian].
33. Kabanets', V. M. (Eds.). (2010). Senchenko Hryhoriy Ivanovych: bibliohrafichnyy pokazhchyk [Senchenko Hryhoriy Ivanovych: bibliographical index]. Sumy [in Ukrainian].
34. Bioresource hemp: Proceeding of the Symposium. (1997). Frankfurt am Main: N. d.
35. Werf van der, H., & Clarke, R. (1998). Interview Dr. V. G. Virovets. Journal of Industrial Hemp Association, 5 (1), 32–33.