Document Type: Original Article


Levity Crop Science Ltd., The Rural Business Centre, Myerscough College, Bilsborrow PR3 0RY, UK


Purpose: Supplying plants with nitrogen in ammonium nitrate- or urea-based fertiliser is wasteful: much is degraded before acquisition, releasing environmental pollutants. Preventing urea degradation can reduce pollution and improve crop nitrogen use efficiency. We investigate benefits to ureic stabilisation, on flowering and stress tolerance, as organic nitrogen sources favourably alter biomass partitioning in this regard. Research Method: We test effects of adding chemically stabilised urea to soil, on the physical form and flowering of containerised, greenhouse-grown pelargonium, petunia, pansy and marigold, when transplanting seedlings to larger pots. Efficacies of stabilised urea, non-stabilised urea and industry standard fertiliser are compared under identical total nitrogen supply. The significance of treatment differences is calculated using a one-tailed t-test. Findings: Development is favourably altered by ureic stabilisation. Earliest changes measured are increased root lengths, leaf growth rates and chlorophyll concentrations. Plants then develop more shoots and 25-130% more flowers. Improvements arise partially through increased nitrogen longevity in soil, and partially through positive effects of urea itself on biomass partitioning between organs, and on plant physiology; giving rise to improved commercial attributes (more branches and flowers) and tolerance to stress (more root, less apical dominance, more chlorophyll). Research Limitations: Further research could measure leachate nitrogen content, and compare different methods of ureic stabilisation in more crops. Originality/Value: Urea stabilisation can increase fruit and flower yields, whilst reducing vulnerability to erratic climates, and fertiliser-derived pollution. We propose that urea’s effectiveness arises because plants have evolved strategies to proliferate whilst competing with micro-organisms for organic nitrogen.


Main Subjects

Andrews, M., Raven, J. & Lea, P. (2013). Do plants need nitrate? The mechanisms by which nitrogen form affects plants. Annals of Applied Biology, 163, 174-199.

Andrews, M., Raven, J.A. & Sprent, J.I. (2001). Environmental effects on dry matter partitioning between shoot and root of crop plants: relations with growth and shoot protein concentration. Annals of Applied Biology, 138, 57-68.

Arkoun, M., Sarda, X., Jannin, L., Laîné, P., Etienne, P., Garcia-Mina, J-M. … & Ourry, A. (2012). Hydroponics versus field lysimeter studies of urea, ammonium and nitrate uptake by oilseed rape (Brassica napus L.). Journal of Experimental Botany, 63, 5245–5258

Barthelemy, H., Stark, S., Michelsen, A., Olofsson, J. (2018). Urine is an important nitrogen source for plants irrespective of vegetation composition in an Arctic tundra: Insights from a 15N‐enriched urea tracer experiment. Journal of Ecology, 106, 367-378.

Bhogal, A., Dampney, P. & Goulding, K. (2003). Evaluation of urea-based nitrogen fertilisers. Report for Defra (UK) projects NT2601 and NT2602.

Brackin, R., Näsholm, T., Robinson, N., Guillou, S., Vinall, K., Lakshmanan, P., …& Inselsbacher, E. (2015). Nitrogen fluxes at the root-soil interface show a mismatch of nitrogen fertilizer supply and sugarcane root uptake capacity. Scientific Reports 5, 15727.

Cambui, C.A., Svennerstam, H., Gruffman, L., Nordin, A., Ganeteg, U. & Näsholm T. (2011). Patterns of plant biomass partitioning depend on nitrogen source. PLoS ONE 6.

Colangelo, D.J. & Brand, M.H. (2001). Nitrate leaching beneath a containerized nursery crop receiving trickle or overhead irrigation. Journal of Environmental Quality 30, 1564-1574. doi:10.2134/jeq2001.3051564x

Forde, B.G. (2002). Local and long range signaling pathways regulating plant responses to nitrate. Annual Review of Plant Biology, 53, 203-224.

Franco, J., Martínez-Sánchez, J.J., Fernandez, J. & Bañón, S. (2006). Selection and nursery production of ornamental plants for landscaping and xerogardening in semi-arid environments. Journal of Horticultural Science and Biotechnology, 81, 3-17. 10.1080/14620316.2006.11512022

Franklin, O., Cambui, C. A., Gruffman, L., Palmroth, S., Oren, R. & Näsholm, T. (2017). The carbon bonus of organic nitrogen enhances nitrogen use efficiency of plants. Plant, Cell & Environment40, 25–35.

Gojon, A., Krouk, G., Perrine-Walker, F. & Laugier, E. (2011). Nitrate transceptor(s) in plants. Journal of Experimental Botany, 62, 2299–2308.

Gou, W., Zheng, P., Tian, L., Gao, M., Zhang, L., Akram, N.A. & Ashraf, M. (2017). Exogenous application of urea and a urease inhibitor improves drought stress tolerance in maize (Zea mays L.) Journal of Plant Research, 130, 599–609.

Hodge, A., Robinson, D., Griffiths, B.S. & Fitter, A.H. (1999). Why plants bother: root proliferation results in increased nitrogen capture from an organic patch when two grasses compete. Plant, Cell & Environment, 22, 811-820.

Huett, D. O. & Morris, S. C. (1999) Fertiliser use efficiency by containerised nursery plants. 3. Effect of heavy leaching and damaged fertiliser prills on plant growth, nutrient uptake, and nutrient loss. Australian Journal of Agricultural Research 50, 217-222.

Ingestad, T. & Ågren, G.I. (1991). The influence of plant nutrition on biomass allocation. Ecological Applications, 1, 168-174.

Kaczperski, M.P., Armitage, A.M. & Lewis, P.M. (1996). Performance of plug-grown geranium seedlings preconditioned with nitrogen fertilizer or low-temperature storage. HortScience 31, 361–363.

Kraiser, T., Gras, D.E., Gutiérrez, A.G., González, B., & Gutiérrez, R.A. (2011). A holistic view of nitrogen acquisition in plants. Journal of Experimental Botany, 62, 1455–1466.

Liu, X., Zhang, Y., Han, W., Tang, A., Shen, J., Cui, Z. … & Zhang, F. (2013). Enhanced nitrogen deposition over China. Nature, 494, 459–462.

Ma, Z., Guo, D., Xu, X., Lu, M., Bardgett, R.D., Eissenstat, D.M. & Hedin, L.O. (2018). Evolutionary history resolves global organization of root functional traits. Nature, 555, 94–97.

Marks, D.J., Wilkinson, S. & Weston, A.K. (2018). Influence of foliar stabilised nitrogen on potato tuber yield. Proceedings Crop Production in Northern Britain, 225-230 (8, 20183245174); pub. by ‘The Association for Crop Protection in Northern Britain, Dundee, UK’. The Dundee Conference. Crop Production in Northern Britain 2018, Dundee, UK, 

Masclaux-Daubresse, C., Daniel-Vedele, F., Dechorgnat, J., Chardon, F., Gaufichon, L. & Suzuki, A. (2010). Nitrogen uptake, assimilation and remobilization in plants: challenges for sustainable and productive agriculture. Annals of Botany, 105, 1141–1157.

Mérigout, P., Lelandais, M., Bitton, F., Renou, J.P., Briand, X., Meyer, C. & Daniel-Vedele, F. (2008). Physiological and transcriptomic aspects of urea uptake and assimilation in Arabidopsis plants. Plant Physiology147, 1225-38. 10.1104/pp.108.119339

Nardi, S., Pizzeghello, D., Schiavon, M. & Ertani, A. (2016). Plant biostimulants: physiological responses induced by protein hydrolyzed-based products and humic substances in plant metabolism. Scientia Agricola73, 18-23.

Neff, J. C., Chapin, F. S. & Vitousek, P. M. (2003). Breaks in the cycle: dissolved organic nitrogen in terrestrial ecosystems. Frontiers in Ecology and the Environment, 1, 205-211.[0205:BITCDO]2.0.CO;2

Paungfoo‐Lonhienne C., Lonhienne T.G.A., Rentsch D., Robinson N., Christie M., Webb R.I., … & Schmidt S. (2008) Plants can use protein as a nitrogen source without assistance from other organisms. Proceedings of the National Academy of Sciences, USA 105, 4524–4529.

Pinton, R., Tomasi, N. & Zanin, L. (2016). Molecular and physiological interactions of urea and nitrate uptake in plants. Plant Signaling and Behaviour, 11, 1.

Pompeiano, A. & Patton, A.J. (2017). Growth and root architecture responses of zoysiagrass to changes in fertilizer nitrate:urea ratio. Journal of Plant Nutrition and Soil Science, 180, 528–534.

Remans, T., Nacry, P., Pervent, M., Filleur, S., Diatloff, E., … Forde, B.G. & Gojon, A. (2006). The Arabidopsis NRT1.1 transporter participates in the signalling pathway triggering root colonization of nitrate rich patches. Proceedings of the National Academy of Science USA, 103, 19206–19211.

Scheible, W.R., Lauerer, M., Schulze, E.D., Caboche, M. & Stitt, M. (1997). Accumulation of nitrate in the shoot acts as a signal to regulate shoot-root allocation in tobacco. Plant Journal 11, 671–691.

Schimel, J.P. & Bennett, J. (2004). Nitrogen mineralization: challenges of a changing paradigm. Ecology, 85, 591-602.

Sunil, B., Talla, S.K., Aswani, V. & Raghavendra, A.S. (2013). Optimization of photosynthesis by multiple metabolic pathways involving inter-organelle interactions: resource sharing and ROS maintenance as the bases. Photosynthesis Research, 117, 61-71.

Tiana, X., Lia, C., Zhang, M., Li, T., Lu, Y. & Liu L. (2018). Controlled release urea improved crop yields and mitigated nitrate leaching under cotton-garlic intercropping system in a 4-year field trial. Soil and Tillage Research, 175, 158-167.

Walch-Liu, P., Liu, L-H., Remans, T., Tester, M. & Forde, B.G. (2006). Evidence that L-glutamate can act as an exogenous signal to modulate root growth and branching in Arabidopsis thalianaPlant and Cell Physiology, 47, 1045–1057.

Wang, S., Zhao, X., Xing, G., Yang, Y., Zhang, M. & Chen H. (2015). Improving grain yield and reducing N loss using polymer-coated urea in southeast China. Agronomy for Sustainable Development, 35, 1103–1115.

Witte, C-P., (2011). Urea metabolism in plants. Plant Science 180, 431-438.

Zandstra, J.W. & Liptay, A. (1999). Nutritional effects on transplant root and shoot growth - A review. Acta Horticulturae 504, 23-32.

Zanin, L., Zamboni, A., Monte, R., Tomasi, N., Varanini, Z., Cesco, S. & Pinton R. (2015). Transcriptomic analysis highlights reciprocal interactions of urea and nitrate for nitrogen acquisition by maize roots. Plant and Cell Physiology, 56, 532-48.

Zerihun A., McKenzie B.A. & Morton J.D. (1998) Photosynthate costs associated with the utilization of different nitrogen‐forms: influence on the carbon balance of plants and shoot‐root biomass partitioning. New Phytologist 138, 1–11.