AVAILABILITY OF PLANT NUTRIENTS FOR PANNONIAN CLOVER (TRIFOLIUM PANNONICUM JACQ.) IN THE FOREST –STEPPE OF WESTERN SIBERIA

Abstract

Hungarian clover (Trifolium pannonicum Jacq.) is a new fodder crop in Russia, with high yield, longevity, balanced chemical composition and low requests to the life conditions. The chemical composition of the сlover largely depends on the availability of nutrients in the key periods of vegetation. The data of macronutrients content in this type of clover are a few and all of them as a rule belong to the European part of Russia. These data are not separate by the type of a shoot. The aim of the work: to determine content and define basic nutritional elements of the shoots (vegetative, generative and their mixture) of Hungarian clover in the various periods of vegetation in the forest-steppe of Western Siberia. The study was conducted in the right-bank part of the Ob River, in the forest-steppe part of the Presalair Plain, on the territory of two agro-climatic subareas of the Novosibirsk Region. The clover shoots of the “Premier” variety (vegetative, generative, and their mixture) were selected according to the vegetation periods in 2018 and analyzed for the total content of nitrogen, phosphorus, potassium, calcium, and magnesium. Hungarian clover, unlike other clovers, is distinguished by the presence of elongated vegetative shoots, the proportion of which varies from season conditions. Separation of shoots by type allowed us to identify their ratio in the total biomass of clover and evaluate the difference in availability at different periods of vegetation. The results of the study showed that the content of nutrients in the shoots of both types decreased from budding to fruiting: nitrogen (1.7 times) -> magnesium (1.5 times) -> phosphorus (1.4 times) -> calcium (1.2 times). The vegetative shoots of Hungarian clover are better provided with nutrients in comparison with generative ones: in the total content of nitrogen, phosphorus and calcium, on average, 1.2 times, potassium and magnesium – 1.3 times. The content of nitrogen and calcium in clover plants was low during the growing season. The optimal phosphorus content in the phase of budding-end of flowering in the fruiting phase turned into a low gradation. The content of total potassium and magnesium was within the optimal supply. In general, the supply of Hungarian clover with nutrients in the forest-steppe of Western Siberia turned out to be higher than Red clover (Trifolium pratense L.), which allows us to recommend it as a promising forage crop.