The effectiveness of the growth regulators and microfertilizers in fertilization of maize in the Western Forest Steppe of Ukraine

Topicality. Fertilizers are one of the most effective means of influencing the yield and quality of maize grain. Along with macroelements (N, P, K), microelements (B, Cu, Fe, Mn, Zn, Mo) play an important role in the formation of maize grain productivity. The need for these elements is small, but they are absolutely necessary for the growth and development of plants. An effective way to provide plants with trace elements during the growing season can be seed treatment and foliar fertilizing, which will contribute to improving the quality of products, increasing yield and economic efficiency of maize cultivation. The use of growth regulators, complex liquid fertilizers is one of the new and promising directions in the agriculture of Ukraine, but little investigated in the conditions of the Western Forest Steppe. Purpose. To study the influence of growth stimulants and complex microfertilizers on the growth and development of plants, the formation of individual productivity indicators, yield and grain quality of maize in the conditions of the Western Forest-Steppe. Materials and Methods. For 2019–2020, the research was conducted on medium loamy podzolized chernozems. In a two-factor experiment, it was studied: DN Meotyda and DB Khotyn hybrids; growth stimulants (Vympel-K, Vympel-2) and microfertilizers (Oracle seeds, Oracle multicomplex, Oracle colofermin zinc, Oracle colofermin magnesium), which were used for seed treatment or spraying of crops in stages of 3–5 and 7–9 leaves. Results. It was established that the maize plants of the studied hybrids formed a different number of ears in the experimental plots, namely, DN Meotyda – 98–108, DB Khotyn – 93–98 productive ears per 100 plants. Pre-sowing seed treatment and foliar feeding of maize at the early growth stages ensured an increase in grain weight per 1 ear of the early-ripening hybrid DN Meotyda by 7.1–27.2 %, and of the mid-early hybrid DB Khotyn – by 5.5–29.4 %, and 1,000 grains weight by 6.9–12.3 % and 10.5–16.0 %, respectively. The grain yield increased by 8.9–27.6 % in the early-ripening hybrid DN Meotyda, and by 8.7–26.1 % in the mid-early hybrid DB Khotyn. Conclusions. The highest indicators of individual productivity and grain yield are provided by the variant that involves seed treatment: Vympel–K + Oracle seed + Oracle zinc; crop treatment in the stage of 3–5 leaves: Vympel–2 + Oracle phosphorus and in the stage of 7–9 leaves: Vympel–2 + Oracle zinc + Oracle magnesium). The grain weight per 1 ear increases by 27.2 for the early-ripening hybrid DN Meotida, by 29.4 % for mid-early DB Khotyn compared to the control; weight of 1,000 grains – by 12.3 and 16.0 %, grain yield – by 27.6 and 26.1 %, respectively. Key words: maize, hybrid, seed treatment, feeding, individual productivity, yield