• Galia Panayotova Trakia University, Bulgaria
  • Svetla Kostadinova Agricultural University, Bulgaria
  • Ivan Velinov Agricultural University, Bulgaria



energy efficiency, nitrogen, wheat, sorghum


The objective of this study was to assess the energy efficiency of nitrogen fertilization in durum wheat and sorghum grains in the period 2017-2019. Bulgarian durum wheat variety Predel was studied at a stationary fertilizer trial on soil type Pellic vertisols at the Institute of Field Crops in Chirpan, Bulgaria. Grain sorghum hybrid EC Alize was investigated on the experimental field of the Agricultural University of Plovdiv, Bulgaria, on soil type Mollic Fluvisols. The crops were grown under non-irrigated conditions. The studied nitrogen rates were 0, 60, 120, 180, and 240 kg N.ha-1. In durum wheat, nitrogen was applied two times: one third at sowing, and the rest - as top dressing in the tillering stage.  In sorghum, the total nitrogen was applied as pre-sowing fertilization before sowing. The nitrogen fertilizer was applied as NH4NO3. The experimental design was a randomized, complete block design with four replications with a size of experimental plots of 20 m2 for both crops. The energy efficiency of nitrogen fertilization (h) was calculated as the ratio between the received energy from additional grain yield of wheat and sorghum, respectively, and the invested energy from fertilization. It was established that energy efficiency of nitrogen fertilization depended on the nitrogen rate and hydro-thermal conditions during the vegetation period of durum wheat and sorghum. The bioenergy coefficient of durum wheat widely varied from 0.79 (N240 in 2018) to 4.44 (N60 in 2017). The average for the period, the highest value of energy efficiency of nitrogen fertilization was obtained at the low rate N60 The higher nitrogen rate of 240 kg N.ha-1 was slightly effective. Under drought conditions during the vegetation period of sorghum, most effective was the application of rates N120 with the highest energy coefficient ​​of 1.23. The application of 180 kg N.ha-1 to sorghum was the most energy efficient under the favorable hydro-thermal conditions in 2018 and 2019, and the average for the period 2017-2019. A low N60 rate in grain sorghum was inefficient from an energy point of view. Durum wheat showed higher energy efficiency of nitrogen fertilization compared to grain sorghum.

Author Biographies

Galia Panayotova, Trakia University, Bulgaria

Trakia University, Faculty of Agriculture, Department of Plant Production, Stara Zagora, Bulgaria

Svetla Kostadinova, Agricultural University, Bulgaria

Agricultural University, Faculty of Agronomy, Department of Agrochemistry and Soil Science, Plovdiv, Bulgaria

Ivan Velinov, Agricultural University, Bulgaria

Agricultural University, Faculty of Agronomy, Department of Agrochemistry and Soil Science, Plovdiv, Bulgaria


Ansari R., Liaqat, M. U., Khan H. I. & Mushtaq, S. (2018). Energy Efficiency Analysis of Wheat Crop under Different Climate- and Soil-Based Irrigation Schedules. Proceedings 2018, 2, 184, 1-7, doi:10.3390/ecws-2-04953.

Azarpour E. (2012). Determination of energy balance and energy indices in wheat production under watered farming in north of Iran. Journal of Agricultural and Biological Science, 7, 250-255.

Beheshti Tabar, I., Keyhani, A. & Rafiee, S.H. (2010). Energy balance in Iran’s agronomy (1990–2006). Renewable and Sustainable Energy Review, 14, 849–855.

Bonin, C.L., Heaton, E.A., Cogdill, T.J. & Moore, K.J. (2016). Management of sweet sorghum for biomass production. Sugar Tech., 18, 150–159.

Cabrera-Ariza, A. M., Tozzini, C., Espinoza-Meza, S.E., Santelices-Moya, R.E., Magni- Canakci, M., Topakci, M., Akinci, I. & Ozmerzi, A. (2005). Energy use pattern of some field crops and vegetable production: case study for Antalya region, Turkey. Energy Convers Manage, 46, 655–66.

Díaz, C.R. & Alonso-Valdés, M.F. (2018). Effect of crop management intensity on energy and carbon dioxide balance of two bioenergy Sorghum bicolor hybrids. Italian Journal of Agronomy, 14(1), 26-33.

Glogova L. (2013). Comparing energy yield and bioenergical coefficient of hybrids sugar and popcorn maize grown at different levels of fertilization. Science and Technologies, III, 224-227 (Bg)

Duncan, D.B. (1955). Multiple range and multiple F- test, Biometrics, 11.

Faidley, L.W. (1992). Energy and Agriculture, In: R.C. Fluck (Editor), Energy in World Agriculture Vol. 6, Elsevier Science Publishers B.V. Amsterdam, The Netherlands, 1-12.

FAO (2006). Guidelines for Soil Description. Rome: FAO.

Hatirli, S.A., Ozkan, B. & Fert, C. (2005). An econometric analysis of energy input–output in Turkish agriculture. Renewable and Sustainable Energy, Reviews, 9, 608–623.

Hosseinpanahi, F. & Kafi, M. (2012). Assess the energy budget in farm production and productivity of potato (Solanum tuberosum L.) in Kurdistan, case study: Plain Dehgolan. Journal of Agroecology, 4, 159–169.

Hülsbergen, K. J. & Klark, W. D. (1997). Stoff- und Energiebilanzen im Dauerfeldversuch, In: Produktionspotentiale in der Landnutzung, Wiss. Beitrage der 5, Hochschultagung der Landwirtschaftlichen Fakultat der Universitat Halle, 192-200.

Jadida, S., Homayounifar, M., Sabuni, M. & Mohammadi, A. (2012). Energy analysis and optimization of inputs for wheat production in Marand region. Indian Journal of Agricultural Sciences 82 (2), 21–24.

Kardoni F., Ahmadi, M. Jami-Al & Bakhshi M.R. (2015). Energy Efficiency Analysis and Modeling the Relationship between Energy Inputs and Wheat Yield in Iran, 2015. International Journal of Agricultural Management and Development, 5(4), 321-330.

Khan S., Khan M.A. & Latif N. (2010). Energy requirements and economic analysis of wheat, rice and barley production in Australia. Soil & Environ., 29 (1), 61-68.

Kostadinova, S. & Yordanova, N. (2010). Fertilization and Energetic Efficiency at Barley variety Kamenica. Field Crops Studies, Vol. VI(1), 91-96.

Kostadinova S., Yordanova, N. & Rachovski, G. (2010). Fertilization and Agronomic Efficiency at Barley variety Kamenica. Field Crops Studies, Vol. VI(1), 85-90.

López-Sandin I, Gutiérrez-Soto G., Gutiérrez-Díez A., Medina-Herrera N., Gutiérrez-Castorena E. & Zavala-García, Fr. (2019). Evaluation of the Use of Energy in the Production of Sweet Sorghum (Sorghum Bicolor L.) under Different Production Systems. Energies,

Meyer-Aurich A, Ziegler T, Jubaer H, Scholz L & Dalgaard T. (2012). Implications of energy efficiency measures in wheat production, Journal Energy, biomass and biological residues. International Conference of Agricultural Engineering - CIGR-AgEng 2012: Agriculture and Engineering for a Healthier Life, Valencia, Spain, 8-12 July 2012, pp. C-0700 pdf.

Mirasi, A., Mousarrezasamadi, K.E. & Taghipoor, M.B. (2014). An assessment of energy efficiency for wheat production in Iran. Elixir Agriculture, 72, 25440-25444.

Mineev, V. (2004). Agrochemistry, University of Moscow, 710-714.

Mishra, J.S., Kumar, R. & Rao, S.S. (2017). Performance of sweet sorghum (Sorghum bicolor) cultivars as a source of green fodder under varying levels of nitrogen in semi-arid tropical India. Sugar Tech., 19, 532–538.

Moghimi, M. R., Alasti, B.M., Drafshi, M.A.H., Ghadim, M.A. & Taki, M. (2013). Energy consumption and assessment of econometric model between input and output for wheat production in Gorve country, Kordestan Province of Iran. Intl J Agri Crop Sci. Vol. 5 (19), 2297-2302.

Moore, S.R. (2010). Energy efficiency in small-scale biointensive organic onion production in Pennsylvania, USA. Renewable Agriculture and Food System 25, 181–188.

Mudahar, M.S. & Hignett, T.P. (1987). Fertilizer and Energy Use, In: Z.R. Helsel (Editor) Energy in Plant Nutrition and Pest Control, Vol. 2, 1-23.

Ozkan, B., Akcaoz, H. & Fert, C. (2004). Energy input–output analysis in Turkish agriculture. Renewable Energy 29, 2939–2951.

Pourazaria, F., Vicoa, G., Båtha, B. & Weiha M. (2015). Nitrogen use efficiency and energy harvest in wheat, maize and grassland ley used for biofuel – implications for sustainability. Procedia Environmental Sciences, 29, 22-23.

Piringer, G. (2006). Re-evaluation of energy use in wheat production in the Unites States. Journal of Industrial Ecology 10(1-2), 149-167.

Rachovski, G., Kostadinova, S., Manolov, I. & Yordanova, N. (2010). Fifth years long-term fertilizing experiment of Agricultural University - Plovdiv, Agricultural University - Plovdiv, Scientific Works, vol. LV, book 1, 93-104 (Bg).

Rocha, A., Araújo, A., Carvalho, A. & Sepulveda, J.A. (2018). New Approach for Real Time Train Energy Effciency Optimization. Energies, 11, 2660.

Uhr Z. & Vasileva, E. (2015). Energy productivity, fertilization rate and profitability of wheat production after various predecessors I. Energy productivity of wheat. Agricultural science and technology, Vol. 7(4), 436-440.

Vermerris, W. & Saballos, A. (2013). Genetic enhancement of sorghumfor biomass utilization. InGenomics of the Saccharinae; Paterson, A., Ed.; Springer: New York, NY, USA, Volume 11, pp. 391–425, ISBN 978-1-4419-5947-8.

Zahedi, M., Eshghizadeh, H.R. & Mondani, F. (2014). Energy Use Efficiency and economical analysis in cotton production system in an Arid region: A case study for Isfahan Province. Iran. Inter. J. Energy Eco. and Poli., 4, 43-52.

Ziaei S.M., Mazloumzadeh, S.M. & Jabbary M. (2015). A comparison of energy use and productivity of wheat and barley (case study). Journal of the Saudi Society of Agricultural Sciences 14, 19–25.




How to Cite

Panayotova, G. ., Kostadinova, S. ., & Velinov, I. . (2020). ENERGY EFFICIENCY OF NITROGEN FERTILIZATION IN DURUM WHEAT AND SORGHUM GRAINS. Proceedings of CBU in Natural Sciences and ICT, 1, 78-84.