Hungarian clover (Trifollium pannonicum Jacq.) - perspective forage crop and phytomeliorant (literary review)

The aim of the study is to present a review of the general characteristics and cultivation of Hungarian clover (Trifolium pannonicum Jacq.) as a forage crop and phytomeliorant in different regions of Russia based on literature data and own experiments. Hungarian clover (Trifolium pannonicum Jacq.) is a perennial legume plant with a natural area of distribution in the countries of Western and Eastern Europe, the northern part of the Balkan Peninsula. The crop is characterized by good adaptability to new ecological and geographical conditions, high winter hardiness, drought resistance, stable seed yield, low susceptibility to diseases and pests, productive longevity (10-15 years), decorativeness, especially during the flowering period (Fig. 1, 4). Fodder from Hungarian clover (hay, haylage and silage) is of excellent or good quality, and the most valuable fodder is obtained when the crop is mown in the budding phase (Table 7-8). At this time, the plants are well leafy, have tender stems and the biggest content of nutrients in the forage mass. These advantages opened up the prospect of the introduction and use of Hungarian clover in different regions of Russia, including the Middle Urals, the Non-Chernozem zone of the country, the Middle Volga region and the south of Western Siberia. In Russia, three varieties of Hungarian clover have been created and best studied: Premier (originators - Siberian Research Institute of Forages and Central Siberian Botanical Garden SB RAS, Novosibirsk), Anik (Penza State Agricultural Academy), Snezhok (Zonal Research Institute of the North-East named after N.V. Rudnitsky, Kirov). These varieties are included in the state register for testing and protection of breeding achievements of the Russian Federation, have successfully proven themselves in fodder production and gardening, as well as a phytomeliorant of disturbed lands, including when regrassing erosion dangerous slopes and restoration of coal mining sites. Analysis of the literature and our own data showed that the plasticity of Hungarian clover allowed it to adapt to the agro-climatic conditions of different regions of Russia, in particular the forest-steppe of Western Siberia, and to give a high, guaranteed seed yield, despite the harsh winters and a short growing season. The morphological structure of Hungarian clover with a very powerful and deeply penetrating root system, multi-stemmed and goblet-shaped bush with large leaves and inflorescences (Fig. 2-3; Table 1-2), gives reasons to speak of the high competitiveness of this crop in relation to the species of natural flora (including rhizome grasses), and also allows us to consider this plant as a promising soil-strengthening plant. Mineral fertilizers (Table 6) and other means of chemicalization have a positive effect on the growth and development of Hungarian clover: field germination, winter hardiness, symbiotic and photosynthetic activity, seed productivity and fodder harvest increase. In terms of the content and set of the main nutrients, Hungarian clover is not inferior to the traditionally cultivated Red clover, and even surpasses it with late mowing. The crop is resistant to pathogens as Erysiphe communis (Wallr.) Grew, Cercospora zebrina Pass, Stemphylium sarciniforme Wiltsh, Pseudopeziza trifolii Fuck, Uromyces fallens (Desm.) Kem. It is possible to sow Hungarian clover in spring and summer (Table 9). The summer sowing period (mid-July) is preferable to use when the field is heavily infested, which allows several presowing cultivations. The wide-row sowing method is inferior in productivity to the row sowing (Fig. 8-9), but it should be noted that the first method is preferable for two main reasons: inter-row cultivation can be carried out and the plants are less prone to lodging than with row sowing with a shoot height of more than 85 cm. Hungarian clover sowing in natural meadow communities allows to increase the yield and nutritional value of the grass stand (Table 4-5; Fig. 5, 7). For example, when the Hungarian clover of the variety Premier is sown into a natural meadow community dominated by an active cenosis-forming agent, Poa angustifolia L., clover remains in the herbage for more than 16 years with a share of at least 50%. Thus, Hungarian clover is a new, promising forage crop in Russia and can be recommended for the creation of highly productive, long-term agrocenoses and as a phytomeliorant of disturbed lands.