Effect of plant growth stimulants on biometric parameters and yield of corn in the Northern Steppe

Abstract

The purpose of the research is to study the effect ofdifferent growth-regulating substances (Vympel 2, AlphaNano Grow, Avantgarde Grow Amino, Avantgarde GrowHumate) on photosynthetic activity, growth and development,and productivity of corn plants of different maturity groups in the conditions of the Northern Steppe of Ukraine. Toidentify the most effective plant growth stimulants on cornthat ensure the acceleration of growth and developmentof the crop, increase resistance to extreme temperatureconditions, increase the development of the leaf surface,increase the protein content of corn grains, increase thechlorophyll content that will ensure an increase in the levelof the crop's productivity potential, effective use of materialand technical and agroclimatic resources.Methods. Field research was conducted in the scientificresearch field of the scientific and educational centerfor practical training of the Dnipro State Agrarian andEconomic University during 2020–2022. General scientificresearch methods were used, the main ones of which were:field – to study the interaction of corn hybrids of differentmaturity groups and growth regulators with biological andabiotic factors; measuring and weighing – for identificationof dynamics of growth, biometric measurements,determination of the elements of the crop structure andgrain yield; mathematical statistics method: dispersion andcorrelation, etc.Results. The use of plant growth stimulants increasedthe height of corn plants by 3–8 cm (1,4–3,7%) comparedto the control (without treatment), especially when sprayedwith the Avantgarde Grow Humate stimulator (1,0 L/ha) –223–225 cm. There was also a tendency to increase thenumber of leaves (by 3,5–5,6%) and the area of leaves (by5,3–28,3%) under the action of growth stimulants without asignificant difference between the formulation used.All the used plant growth stimulants had a significanteffect on the content of chlorophyll (SPAD units), inparticular, on the hybrid DN Pyvykha FAO 180 – 8,1–9,1 units(17,9–19,6%), DN Khortytsia FAO 240 – 9,2–12,8 units(18,2–23,7%), DN Julia 340 MV FAO 340 – 2,3–6,6 units(4,6–12,2%), DN Olena 440 MV FAO 440 – 1,5–6,0 units(3,1–11,3%). A trend of growth in chlorophyll content wasnoted when applying Avantgarde Grow Amino – 1,5 L/haand Avantgarde Grow Humate – 1,0 L/ha compared toVympel 2 – 0,5 L/ha and Alpha Nano Grow – 50 ml/ha.Conclusions. Higher indicators of the content ofchlorophyll in the leaves contributed to an increase inthe level of yield in the early-season hybrid DN PyvykhaFAO 180 by 0,12–0,36 t/ha (2,6–7,6%), middle-earlyDN Khortytsia FAO 240 – 0,84–1,07 t/ha (16,5–18,4%),mid-season DN Julia 340 MV FAO 340 – 0,19–0,2 t/ha(3,19–3,3%), middle-late DN Olena 440 MV FAO 440 –0,04–0,5 t/ha (0,64–7,5%).