Effect of mineral fertilizers on the formation of the structure indicators of grain sorghum yield capacity

ISSN 2410-1303 (online) Новітні агротехнології, 2023, Т. 11, № 3 doi: 10.47414/na.11.3.2023.288680 Рослинництво UDC 633:174:631.5 Effect of mineral fertilizers on the formation of the structure indicators of grain sorghum yield capacity 1 L. A. Pravdyva*, O. I. Prysiazhniuk, V. A. Doronin Institute of Bioenergy Crops and Sugar Beet of NAAS, 25 Klinichna St., Kyiv, Ukraine, *e-mail: Abstract. In the process of gradual warming, producers carry out the search of the crops, which develop high productivity of excellent quality grain in the difficult soil-climatic conditions. Grain sorghum is one of these crops. Similar to any other agricultural crop, its productivity depends on the effect of numerous factors including the elements of the cultivation technology. One of these elements is the application of mineral fertilizers. The purpose of the research was to study the effect of the plant mineral nutrition on the formation of the structure indicators of grain sorghum yield capacity in the conditions of the Right bank Forest steppe zone of Ukraine. The experiment was carried out in the zone of unstable humidity in 2016–2020. The trial scheme consisted in studying grain sorghum cultivars and various fertilizer rates; the trial was initiated with the method of regular replications, a fourfold replication was applied. Having analyzed the research results, it was found out that as the fertilizer rates increased, the element indicators of the yield structure also increased; in turn grain yield capacity of the studied cultivars was higher. However, the optimal fertilizer rate for the expected yield is the estimated one which will reduce the production cost of the output. Keywords: rates; cultivars; productivity; correlation. Introduction Sorghum is a unique cereal plant both in terms of its biological peculiarities and economically valuable features. Sorghum is the fifth largest grain crop in the world after wheat, rice, corn and barley. The homeland of sorghum is Equatorial or Northeast Africa. Derivative centers of its origin are considered to be India and China, from where it was imported to other countries [1, 2]. In some regions, this crop replaces corn due to its high yield capacity, drought and heat resistance [3, 4]. Sorghum is adapted to a wide range of environments, it is grown in the tropics as well as in arid regions of the world. As a C 4 plant, sorghum effectively fixes carbon in high and low temperature environments. Conversely, it is the resistance of sorghum to waterlogging that helps it thrive in tropical environments. This is a universal short-day crop, as it uses moisture and precipitation effectively, restores its growth after a long dry period and forms a fairly high yield, which means it can be grown in arid areas [5, 6]. In the context of climate change and variability, increasing small grain yield is critical for food and nutrition security [7]. Droughts and low soil fertility are common in semi-arid regions, trapping smallholder farmers in a cycle of poverty [8]. Drought is a primary sorghum production constraint and is the leading cause of yield decrease [9]. Grain sorghum is a key food crop for food production and for the use in fodder production [10, 11]. In the arid and semi-arid regions of the developing world, millions of people consume sorghum as their main source of food, while it is mainly used for livestock feed and for industrial use, namely for bioethanol production in the industrialized countries, including the United States of America [12–14]. Recently sorghum grain production has increased. Modern varieties and hybrids have a high potential for productivity, and are suitable for the use of intensive technologies for the production of feed grain. Increased requirements to organic production necessitate the nutritional parameter optimization in the conditions of the unstable agriculture with the unbalanced accumulation of nutrients in the soil. The 1 Pravdyva, L. A., Prysiazhniuk, O. I., & Doronin, V. A. (2023). Effect of mineral fertilizers on the formation of the structure indicators of grain sorghum yield capacity. Advanced Agritechnologies, 11(3). https://doi.org/10.47414/na.11.3.2023.288680 http://jna.bio.gov.ua L. A. Pravdyva, O. I. Prysiazhniuk, V. A. Doronin mineral fertilizer application is one of the most effective factors influencing the dynamics of grain sorghum growth and development, its ability to form high yield capacity and grain quality in different climatic conditions [15–17]. Grain sorghum responds positively to the application of mineral fertilizers, it consumes only 38.7% of nutrients of the total uptake from soil reserves [18]. According to some scientists [19, 20], it has been investigated that half of the increase in crop yield capacity can be obtained due to fertilizers. It has been proved that biometric and yield structure indicators are influenced by different tillage practices, varieties and the level of mineral fertilizers [21]. In South-Eastern Romania, it is recommended to grow grain sorghum using a rate of mineral fertilizers N120P60K60, having obtained the highest grain yield capacity [22]. In India the recommended rate of fertilizers is N80P40K40, which provides a higher net profit and a low cost of cultivation [23]. In Ukraine, according to the authors, the optimal rate of fertilizers for growing grain sorghum was the application of N60P60K60. According to this technology, crop productivity was 8.0–8.49 t ha–1 [1, 18]. According to many scientists, the effective use of fertilizers can increase the resistance of grain sorghum to unfavorable external factors, increase germination energy, ensure the intensive growth at the early stages of organogenesis and a high productivity of generative organs [24–26]. Inadequate and imbalanced application of fertilization to crops not only leads to low crop yields but also decreases soil quality [27]. In Ukraine, the issue of studying the effect of different rates of grain sorghum fertilizers on the elements of crop yield structure has been studied insufficiently, so it requires some detailed research. By optimizing the technology elements of the cultivation of agricultural crops, including grain sorghum, it is possible to influence the formation of the elements of the yield capacity structure and, accordingly, to obtain high and sustainable productivity. The structure elements of the grain sorghum yields include such indicators as the number of panicles per hectare, the number of grains in the panicle, the mass of grain in the panicle, the mass of 1000 seeds, etc. [28]. The aim of the work was to study the effect of plant mineral nutrition on the formation of the structure indicators of grain sorghum yield capacity in the conditions of the Right-Bank Forest-Steppe zone of Ukraine. Materials and methods The research was carried out in Bila Tserkva research-breeding station of the Institute of bio-energy crops and sugar beet of Ukraine’s National Academy of Agr (...truncated)