The Effect of Growth Stimulants based on Humic Acids from Ukrainian Lignite and Biochar from Agricultural Residues on the Growth and Development of Lettuce (Lactuca sativa)
Agronomy Research 2025
Maryna Zhylina, Pavlo Karnozhytskyi, Denis Miroshnichenko, Vladimir Konohrai, Vita sterna, Jurijs Ozoliņš

Significant amounts of plant-based waste are generated annually in the agricultural and food industries, including straw, corn residues, nutshells, and fruit pits. Disposing of this waste often relies on basic methods that avoid further processing, presenting an urgent environmental challenge. One efficient solution is converting biomass into biochar, which serves as a soil amendment. Developing cost-effective recycling methods has become critical with the increasing scarcity and rising cost of raw materials. The Dnipro Lignite Coal Basin in Ukraine offers extensive lignite reserves, enabling the production of affordable, high-quality humates for soil enhancement. In this study, wheat and barley straw were pelletized with barley bran at a 90:10 ratio. Pyrolysis was conducted at 500 °C with a heating rate of 5 °C·min⁻¹ and a one-hour holding time. The resulting biochar was added to a lettuce cultivation substrate at a 1:10 biochar-to-peat ratio. Humic substances derived from lignite were applied in 3% and 9% aqueous solutions, and environmental conditions, such as humidity and temperature, were monitored throughout the 35-day trial. Results showed that granulated biochar increased lettuce rosette diameter by 7.5% compared to perlite substrates and by 11.6% compared to peat. Additionally, 3% humate solutions enhanced rosette diameter by 11.6% and biomass weight by 25.77%. These findings confirm that biochar from agricultural residues and lignite-derived humates effectively boost lettuce yield and quality.


Keywords
agro-ecology, biochar, biomass, agricultural residues, lignite-derived humates, soil quality, Lactuca sativa, growth stimulants, carbon cycle, crop, renewable resources, articles
DOI
10.15159/ar.25.013
Hyperlink
https://dspace.emu.ee/items/f6a815a6-074a-45d5-9622-2e02c11c30e0

Zhylina, M., Karnozhytskyi, P., Miroshnichenko, D., Konohrai, V., Sterna, V., Ozoliņš, J. The Effect of Growth Stimulants based on Humic Acids from Ukrainian Lignite and Biochar from Agricultural Residues on the Growth and Development of Lettuce (Lactuca sativa). Agronomy Research, 2025, Vol. 23, No. 1, pp.571-584. ISSN 1406-894X. Available from: doi:10.15159/ar.25.013

Publication language
English (en)
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