Effects of complex of microelements and ecological factors on winter wheat productivity

Abstract

Soil properties are the most important environmental factors in the formation of the norms for the use of microelements in winter wheat cultivation. However, specific agroclimatic growing conditions and their combinations often necessitate the use of trace elements in the agroecosystem. Humus substances of different nature enriched with microelements and the content of mobile carbonates can serve as another factor in increasing yields. The micronutrient nutrition of winter wheat in the arid climate of the Northern Steppe of Ukraine on washed out chernozems, which are zonal soils of this territory under current conditions of climate change and intensive farming, has its own characteristics. The aim of the research was to study the influence of soil ecological factors on the yield of winter wheat applying foliar fertilization with microelements (Zn, Cu, B, Mo, Co, P2O5, K2O) at the rate of 2.5 L·ha-1 and 5 L·ha-1. The research was conducted on ordinary low-humus, slightly and moderately leached chernozems, in the profile of which carbonates were raised due to the leaching of the upper accumulative genetic horizon and the deterioration of soil fertility. The yield of winter wheat on ordinary unwashed chernozem was 15.1% higher when applying the norm of 2.5 L·ha-1 of the microelement’s preparation compared to the control, while on washed soils the effect was less – 3.6–8.8%. When applying the norm of 5 L·ha-1 of the microelements preparation on washed out soils, the yield increase was up to 12.0% on medium washed out, 9.6 on slightly washed out and 0.8% on unwashed out chernozem. The content of microelements in grain increased with the increase in the dose of microelements in the fertilizer. Under dry conditions and a large amount of plant residues from the previous crop, which contributed to an increase in water-soluble phenols and soil fatigue, it is recommended to completely abandon minimal tillage in order to avoid ploughing plant residues into the surface layer of the soil or ploughing. When the rate of microelements use was doubled (5 L·ha-1), a positive effect was observed on the eroded ordinary chernozem soils and the yield increase was on average 11.0%. The study emphasizes the importance of adapting fertilizer application practices to soil properties and climate, especially in conditions of drought and high phenol content.