Aim. The aim of this article is to analyze the current state of plant nomenclature in agricultural practice. Methods. The analysis of literary sources, mathematical analysis. Results. In the titles of 1760 analyzed dissertations for the scientific degrees in agricultural sciences (2000–2019), 90.3% of the plant names are presented in Ukrainian, 5.6% are a combination of Ukrainian and Latin names, and 4.1% are in Latin. In the titles of 680 dissertations for the scientific degrees in biological sciences, the main part is made up of the Latin names of taxa of a generic and species rank and below — 45.2%, names in Ukrainian are 35.1%, and combinations of Ukrainian and Latin names are 19.7%. Despite the fact that the same groups of organisms are studied in both groups agricultural and biological, there are significant differences in the use of names. The scientific style of the Ukrainian language is inherent in the direct word order when the adjective precedes the noun. This is how crop names were coined: miaka pshenytsia (common wheat), tverda pshenytsia (durum wheat), ozyma pshenytsia (winter wheat), yara pshenytsia (spring wheat), tsukrovi buriaky (sugar beet), etc., while in the names of botanical taxa the word order is opposite: pshenytsia miaka (common wheat), pshenytsia tverda (durum wheat), buriak zvychainyi (beet), etc. In the last quarter of the twentieth century, unmotivated inversion occurred in the catalogues of zoned cultivars of agricultural crops, when the word order in the crop names changed to the opposite. In the International Convention for the Protection of Rights of New Varieties of Plants, the term variety is associated with the term taxon, and not agricultural crop. Therefore, the concepts of agricultural crop and botanical taxon that are not identical are confused in the State Register of Plant Varieties of Ukraine. Agrarians have been in a state of ambiguity and uncertainty regarding the proper use of plant names. The attempts to assimilate the agrobiological nomenclature to the botanical one led to an unreasonable replacement of the names of cultons, which acquired a chaotic and mass character. At the beginning of the 20th century, in the vast majority of dissertations in the agricultural field, the spelling of the names of traditional crops corresponded to the scientific style, but gradually it changed and now in most dissertations the reverse word order dominates, mistakenly identifying the crop names with specific names. At the same time, in biological dissertation, the names of both cultons and taxa correspond to the scientific style. Conclusions. The titles of many dissertations for the scientific degrees in Agricultural and Biological Sciences use Ukrainian and Latin names of plants. Latin names are regulated by the ICN, but the Ukrainian ones belong to two unregulated terminological systems. The first botanical system reflects the scientific botanical nomenclature and manages the names of taxon, the second agrobiological system is based on the names of cultons. Generic names and crop names often coincide, while species names and crop names differ in word order. In the verbose crop names, the word order is direct with the adjective precedes the noun, in the species names the word order is reversed, a generic name followed by a specific epithet. The phenomenon of replacing crop names with names inheriting the species names has become rampant over the past twenty years. They destroy the system of agrobiological nomenclature and contradict the scientific standards of the literary Ukrainian language. The identification of this negative phenomenon will allow us to overcome it faster.