Effectiveness of zinc in foliar feeding maize in the Western Forest Steppe of Ukraine

Abstract

Topicality. Maize requires not only macronutrients such as nitrogen, phosphorus and potassium, but also micronutrients such as Cu, Mo, Mn, Co, Zn, B, etc. for optimal development. In maize cultivation technologies, the effectiveness of micronutrient fertilisers is quite high, regardless of the application method (pre-sowing seed treatment or foliar feeding). Among the micronutrients, zinc is especially important in plant life, as its deficiency leads to a growth slowdown due to reduced internodes, reduced ear grain content or lack of ear setting. Purpose. To study the effectiveness of applying zinc in the form of a highly concentrated liquid fertiliser for foliar feeding maize and its impact on plant growth and development, leaf area formation, individual productivity, and grain yield in the Western Forest-Steppe. Materials and Methods. In a two-factor experiment, early-ripening DN Aton and mid-early DN Astra maize hybrids were studied; highly concentrated liquid zinc fertilizer Chimic Zinc was applied to spray crops in the 5–6 and 8–9 leaf stages. Results. It was established that the linear dimensions of plants are determined by the genetic characteristics of hybrids and significantly depend on their maturity group and mineral nutrition. In particular, the plant height of the early-ripening hybrid DN Aton in the tasseling stage was 200.0 cm and of the mid-early hybrid DN Astra – 210.7 cm in the control, while it increased to 225.1 and 238.3 cm, respectively, due to two-time zinc feeding. The leaf surface area of the early-ripening hybrid DN Aton increased from 31.57 to 34.67 thousand m2/ha, in the mid-early hybrid DN Astra – from 33.59 to 36.99 thousand m2/ha. Variation in the number of productive ears and yield structure indicators by experimental variants certainly influenced the formation of grain yield. Maize yield increased by 0.72 t/ha (8.2 %) in the early ripening hybrid DN Aton and by 0.78 t/ha (8.6 %) in the mid-early hybrid DN Astra compared to the control due to the zinc application for foliar feeding of maize in the 5–6 and 8–9 leaf stages. Conclusions. Foliar feeding maize in stages of 5–6 and 8–9 leaves with highly concentrated liquid zinc fertilizer Chimic Zinc has a positive effect on the plant growth and development, the formation of leaf surface area and photosynthetic potential, increases in the number of productive ears per 100 plants, improves indicators of yield structure elements, which contributes to higher grain yield. Key words: maize, hybrid, development stage, feeding, leaf surface area, individual productivity, yield