Patricio Grassini

Patricio Grassini

Associate Professor

B.Sc. (Agricultural Engineer). University of Buenos Aires, Argentina (2005)

Ph.D. (Agronomy). University of Nebraska-Lincoln (2010)

Area of Focus


Research Interests

  • Crop physiology
  • Yield potential
  • Yield-gap analysis
  • Resource- and Energy-use efficiency
  • Crop simulation models

Major Project Activities

I have performed yield-gap and resource-use efficiency analysis across a diverse range of cropping systems, ranging from rainfed cereal crops in Sub-Saharan Africa to high-yield maize-soybean systems in the North Central US region and South-East Asia. I am currently involved in two major programs:

1. Global Yield Gap and Water Productivity Atlas. The global community must find a way to provide food and water security for a population expected to reach 9 billion by 2050. Global carrying capacity for food production and our ability to protect carbon-rich and biodiverse natural ecosystems from conversion to cropland ultimately depend on achieving maximum possible yields on every acre of currently used arable land. The Global Yield Gap and Water Productivity Atlas ( provides a web-based platform for estimating yield potential, yield gaps, and water productivity that is transparent, accessible, reproducible, geospatially explicit, agronomically robust and applied in a consistent manner throughout the world. The Atlas allows to: (i) identify regions with the greatest potential to increase food supply and water productivity; (ii) prioritize research investments and monitor impact, and (iii) evaluate the impact of climate change and other issues that deal with water, food, and weather. The Atlas has been developed for ca. 55 countries across five continents, and includes all major cereal crops. Recently, the crop list has been extended to include soybean, sugarcane, and potatoes. We are also adding information on water productivity and nutrient requirements. As the Atlas provides open access to all underpinning weather, soil and agronomic data, the database is a unique starting point for all sorts of scientific, strategic and applied questions.

2. Benchmarking yield and input-use efficiency of corn-soybean systems in the North-Central US region. Though it has been speculated that the efficiency with which applied inputs result in increased yield can be greater in intensively managed high-yield cropping systems than in their low-input low-yield counterparts due to optimization of growing conditions in the former, this hypothesis has not been evaluated in actual cropping systems where farmer yields approach yield potential as it is the case of corn-soybean agro-ecosystems in the North Central US region. Our research program is explicitly oriented towards identification of management practices that allow achieving high yield with high efficiency, and without sacrificing producer profit. As a complement to the more traditional research approach of running experiments in experimental stations or a limited number of site-years, we built collaborative links with Nebraska Natural Resources Districts and commodity groups to collect data on yield and applied inputs from thousands of producer corn and soybean fields in the North Central US region. We use these data to (i) diagnose current yields, yield gaps, and input-use efficiency of irrigated and dryland crop systems, and (ii) identify opportunities to improve yields, efficiencies, and farm profit.

Extension Interests

I actively participate in extension activities, including University of Nebraska–Lincoln Crop Extension Clinics, NRD-sponsored workshops, and training sessions on the use of crop simulation models as decision-support tools to optimize crop management and producer profit, and write extension publications, including CropWatch articles, Crop Production Clinic Proceedings, and Extension Circulars. I also deliver bi-weekly, in-season, real-time forecasting of irrigated and rainfed end-of season corn yield potential for more than 40 locations across the US Corn Belt , which are periodically published as CropWatch articles during the crop season (see This information is used by crop producers, consultants and ag industry for making in-season adjustments on crop management, farm logistics, and grain marketing.


  • Agronomy Society of America (ASA) Early Career Award (2016)
  • Member of Science Advisory Council for Field to Market (since May 2016)
  • Junior Faculty Excellence in Research Award. University of Nebraska–Lincoln (2015)
  • Member of the Editorial Advisory Board of Field Crops Research and Global Food Security journals
  • Water for Food Institute Fellow
  • Center for Great Plains Studies Fellow
  • ASABE Blue Ribbon Award, Educational Aids Competition (2013)
  • Fulbright Scholar (2007-2009)
  • Maude Hammond Fling Fellowship. University of Nebraska–Lincoln (2009-2010)
  • Widaman Distinguished Graduate Assistant Award. University of Nebraska–Lincoln (2009)
  • Gerald O. Mott Meritorious Graduate Student Award in Crop Science. Agronomy Society of America (2009).
  • William J. Curtis Endowed Fellowship. University of Nebraska–Lincoln (2007)
  • Diploma of Honor. University of Buenos Aires (2006)


h-index: 24; i10-index: 37; total citations: 2,890 (checked with Google Scholar® by Aug 20, 2018)

  • Rizzo G, Rattalino Edreira JI, Archontoulis SV, Yang HS, Grassini P (2018) Do shallow water tables contribute to high and stable maize yields in the US Corn Belt? Global Food Sec. 18, 27-34.
  • Agustiani N, Deng N, Rattalino Edreira JI, Girsang SS, Syafruddin S, Sitaresmia T, Pasuquin JM, Agus F, Grassini P (2018) Simulating rice and maize yield potential in the humid tropical environment of Indonesia. European J. of Agronomy (In Press).
  • Rattalino Edreira, Guilpart N, Sadras V, Cassman KG, van Ittersum MK, Schils RLM, Grassini P (2018) Water productivity of rainfed maize and wheat: a local to global perspectives. Agric. For. Meteorology 259, 364-373.
  • Rattalino Edreira JI, Cassman KG, Hochman Z, van Ittersum MK, van Bussel L, Claessens L, Grassini P (2018) Beyond the plot: Technology extrapolation domains for scaling out agronomic science. Environmental Research Letters 13, 054027
  • Mourtzinis S, Rattalino Edreira JI, Grassini P, Roth A, Ciampitti IA, Licht MA , Kandel H, Kyveryga PM , Lindsey LE , Mueller DS, Naeve SL, Nafziger E, Specht JE, Stanley J, Staton MJ, Conley SP (2018) Sifting and winnowing: Analysis of farmer field data for soybean in the US North-Central region. Field Crops Res. 221, 130-141.
  • Gibson K, Yang H, Franz T, Eisenhauer D, Gates J, Nasta P, Farmaha B, Grassini P (2018) Assessing explanatory factors for variation in on-farm irrigation in US maize-soybean systems. Agricultural Water Management 197, 34–40.
  • Timsina J, Wolf J, Guilpart N, van Bussel LGJ, Grassini P, van Wart J, Hossain A, Rashid H, Islam S, van Ittersum MK (2018) Can Bangladesh produce enough cereals to meet future demand? Agric Syst 163, 36-44.
  • Guilpart N, Grassini P, Van Wart J, Yang H, van Ittersum M, van Bussel L, Wolf J, Claessens L, Leenars J, Cassman KG (2017) Rooting for Food Security in Sub-Saharan Africa. Environmental Research Letters 12, 114036.
  • Cafaro La Menza N, Monzon JP, Specht J, Grassini P (2017) Is soybean yield limited by nitrogen supply? Field Crops Res. 213, 204-212.
  • Rattalino Edreira JI, Mourtzinis S, Conley SP, Roth A, Ciampitti IA, Licht MA , Kandel H, Kyveryga PM , Lindsey LE , Mueller DS, Naeve SL, Nafziger E, Specht JE, Stanley J, Staton MJ, Grassini P (2017) Assessing causes of yield gaps in agricultural areas with diversity in climate and soils. Agric. For. Meteoro. 247, 170-180.
  • Thomson AM, Ramsey A, Barnes E, Basso B, Eve M, Gennet S, Grassini P, Kliethermis B, Matlock M, McClellen E, Spevak E, Snyder C, Tomer M, van Kessel C, West T, Wick G (2017) Science in the Supply Chain: Collaboration opportunities for advancing sustainable agriculture. Agricultural & Environmental Letters 2, 170015
  • Tenorio FM, Specht JE, Arkebauer TJ, Eskridge KM, Graef GL, Grassini P (2017) Co-ordination between primordium formation and leaf appearance in soybean (Glycine Max) as influenced by temperature. Field Crops Res. 210, 197-206
  • Grassini P, Pittelkow CM, Cassman KG, Yang HS, Archontoulis S, Licht M, Lamkey KR, Ciampitti IA, Coulter JA, Brouder SM, Volenec JJ, Guindin-Garcia N (2017) Robust spatial frameworks for leveraging research on sustainable crop intensification. Global Food Security 14, 18-22.
  • Grassini P, Cassman KG, van Ittersum MK (2017) Exploring maize with the Global Yield Gap Atlas. Better Crops 101, 7-9
  • de Groot H, Adimo O, Claessens L, Van Wart J, van Bussel LGJ, Grassini P, Wolf J, Guilpart N, Boogaard H, van Oort PAJ, Yang HS, van Ittersum MK, Cassman KG (2017) Kenya public weather processed by the Global Yield Gap Atlas project. ODJAR 3, 1-3.
  • Guilpart N, Grassini P, Sadras VO, Timsina J, Cassman KG (2017). Estimating yield gaps at the cropping system level. Field Crops Res. 206, 21-32.
  • Gibson J, Trenton EF, Wang T, Gates J, Grassini P, Yang H, Eisenhauer D (2017) A case study of field-scale maize irrigation patterns in western Nebraska: implications for water managers and recommendations for hyper-resolution land surface modeling. Hydrol. Earth Syst Sci. 21, 1051-1062.
  • Yang H, Grassini P, Cassman KG, Aiken RM, Coyne PI (2017). Improvements to the Hybrid-Maize model for simulating maize yields in harsh rainfed environments. Field Crops Res. 204, 180-190.
  • Mourtzinis S, Rattalino Edreira JI, Conley SP, Grassini P (2017) From grid to field: assessing quality of gridded weather data for agricultural applications. European J. of Agronomy 82, 163-172.
  • van Oort PAJ, Saito K, Dieng I, Grassini P, Cassman KG, van Ittersum MK (2017) Can yield gap analysis be used to inform R&D prioritization? Global Food Security 12, 109-118.
  • van Ittersum MK, van Bussel LGJ, Wolf J, Grassini P, van Wart J, Guilpart N, Claessens L, de Groot H, Wiebe K, Mason-D’Croz D, Yang SH, Boogaard H. van Oort PAJ, van Loon M, Saito K, Adimo O, Adjei-Nsiah S, Alhassane A, Bala A, Chikowo R, Kaizzi KC, Kouressy M, Makoi JHJR, Ouattara K, Tesfaye K, Cassman KG (2016). Can sub-Saharan Africa feed itself? Proc. Natl. Acad. Sci. (PNAS) 113, 14964-14969
  • Espe MB, Cassman KG, Yang H, Guilpart N, Van Wart J, Grassini P, Anders M, Beighley D, Harrell D, Linscombe S, McKenzie K, Mutters R, Wilson T, Linquist BA (2016) Yield gap analysis of US rice production systems shows opportunities for improvement. Field Crops Res. 196, 276-283.
  • Farmaha BS, Eskridge KM, Cassman KG, Specht JE, Yang H, Grassini P (2016). Rotation impact on on-farm yield and input-use efficiency in high-yield irrigated maize-soybean systems. Agron. J. 108, 1-9.
  • Wortmann C, Grassini P, Elmore RW (2016) Optimizing maize-based cropping systems: sustainability, good agricultural practices (GAP) and yield goals. In: Watson, D. (ed.), Achieving sustainable cultivation of maize Volume 2: Cultivation techniques, pest and disease control, Burleigh Dodds Science Publishing, Cambridge, UK
  • Grassini P, Rees J, Specht, J, Cafaro La Menza N 2016. What does it take to produce 80 bu/ac soybean? Extension Circular 3000. University of Nebraska–Lincoln. URL:
  • Morell FJ, Yang HS, Cassman KG, Van Wart J, Elmore RW, Licht M, Coulter JA, Ciampitti IA, Pittelkow CM, Brouder SM, Thomison P, Lauer J, Graham C, Massey R, Grassini P, 2016. Can crop simulation models be used to predict local to regional maize yields and total production in the U.S. Corn Belt? Field Crops Res. 192, 1-12.
  • Gobett D, Hochman Z, Horan H, Navarro-Garcia J, Grassini P, Cassman KG,  2016. Yield gap analysis of rainfed wheat demonstrates local to global relevance. Journal of Agric. Sci. (Cambridge) (Accepted)
  • Zanon AJ, Steck NA, Grassini P, 2016. Climate and management factors influence soybean yield potential in a subtropical environment. Agron. J. 108, 1-8.
  • Marin F, Martha G, Cassman KG, Grassini P, 2016. Prospects for increasing sugarcane and bioethanol production on existing crop area in Brazil. BioScience 66, 307-316.
  • Farmaha BS, Lobell DB, Boone K, Cassman KG, Yang, SH, Grassini P, 2016. Contribution of persistent factors to yield gaps in high-yield irrigated maize. Field Crops Research 186, 124-132.
  • Aramburu Merlos F., Monzon JP, Mercau JL, Taboada, M, Andrade, FH, Hall AJ, Jobbagy E, Cassman KG, Grassini P, 2015. Potential for crop production increase in Argentina through closure of existing yield gaps. Field Crops Research 184, 145-154.
  • Makowski D, Asseng S, Ewert F, Bassu S., Durand JL, Lie T, Martre P, Adamh M, Aggarwal PK, Angulo C, Baron C, Basso B, Bertuzzi P, Biernath C, Boogaard H, Boote KJ, Bouman B, Bregaglio S, Brisson N, Buis S, Cammarano D, Challinorr AJ, Confalonieri R, Conijnu JG, Corbeels M, Deryng  D, De Sanctis G, Doltra J, Fumoto T, Gaydon D, Gayler S, Goldberg R, Grant RF, Grassini P, et al., 2015.  A statistical analysis of three ensembles of crop model responses to temperature and CO2 concentration. Agric. Forest Meteoro. 214, 483-493. 
  • Grassini P, Torrion JA, Yang HS, Rees J, Andersen D, Cassman KG, Specht JE, 2015. Soybean yield gaps and water productivity in the western U.S. Corn Belt. Field Crops Res. 179, 150-163.
  • Van Wart J, Grassini P, Yang HS, Claessens L, Jarvis A, Cassman KG, 2015. Creating long-term weather data from thin air for crop simulation modelling. Agric. Forest Meteoro. 208, 49-58.  LINK:
  • Grassini P, Van Bussel LGJ, Van Wart J, Wolf J, Claessens L, Yang H, Boogaard H, de Groot H, Van Ittersum MK, Cassman KG, 2015. How good is good enough? Data requirements for reliable crop yield simulations and yield-gap analysis. Field Crops Res. 177, 49-63. LINK:
  • Van Bussel LGJ, Grassini P, Van Wart J, Wolf J, Claessens L, Yang H, Boogaard H, de Groot H, Saito K, Cassman KG, Van Ittersum MK, 2015. From field to atlas: Upscaling of location-specific yield gap estimates. Field Crops Res. 177, 98-108. 
  • Kranz W, Burr C, Farmaha B, Grassini P, Hergert G, Irmak I, Martin D, Nygren A, Shapiro C, Shaver T,  Zoubek G. 2015. Irrigation and Nitrogen Management: User Education/Certification Program. EC2008 Nebraska Extension Division. 117 pp.
  • Grassini P, Morell Soler F, Yang H, Cassman KG, Elmore R, Rees J, Glewen K, Shapiro C, Kruger G. 2015. In-season yield forecasting using a computer simulation model. 2015 Crop Production Clinics Proceedings. University of Nebraska-Lincoln - Extension. LINK: documents/15-5010-2015%20Crop%20Production%20Clinic.pdf
  • Sadras V, Cassman KG, Grassini P, Hall AJ, Bastiaansen, WGM, Laborte AG, Milne AE, Sileshi G, Steduto P, 2015. Yield gap analysis of rainfed and irrigated crops: Methods and case studies. In: FAO Water Reports 41. Food and Agriculture Organization of the United Nations (FAO), Rome. 
  • Sadras VO, Grassini P, Costa R, Cohan L, Hall AJ, 2014. How reliable are crop production data? Case studies in USA and Argentina. Food Security 6, 447-459.
  • Sadras VO, Grassini P, Costa R, Cohan L, Hall AJ. (2014). How reliable are crop production data? Case studies in USA and Argentina. Food Security DOI 10.1007/s12571-014-0361-5
  • Grassini P, Torrion JA, Cassman KG, Yang HS, Specht JE., (2014). Drivers of spatial and temporal variation in soybean yield and irrigation requirements. Field Crops Res. 163, 32-46
  • Bassu S, Brisson N, Durand J-L, Boote K, Lizaso J, Jones JW, Rosenzweig C, Ruane AC, Adam M, Baron C, Basso B, Biernath C, Boogaard H, Conijn S, Corbeels M, Deryng D, De Sanctis G, Gayler S, Grassini P, Hatfield J, Hoek S, Izaurralde C, Jongschaap R, Kemanian AR, Kersebaum KC, Kim S-H, Kumar NS, Makowski D, Mø¼ller C, Nendel C, Priesack E, Pravia MV, Sau F, Shcherbak I, Tao F, Teixeira E, Timlin D, Waha K. (2014). How do various maize crop models vary in their responses to climate change factors? Global Change Biology 20, 2301-2320.
  • Grassini P., Eskridge K., Cassman K.G. (2014) Distinguishing between yield advances and yield plateaus in historical crop production trends. Nat. Commun. 4:2918 | DOI: 10.1038/ncomms3918.  LINK:
  • Specht, J.E., Diers, B.W., Nelson, R.L., Toledo, J.F., Torrion, J.A., Grassini, P., (2014). Soybean (Glycine max (L.) Merr.). In: Smith, J.S.C, Carver, B., Diers, B.W., Specht, J.E. (Eds.), Yield Gains in Major US Field Crops: Contributing Factors and Future Prospects. CSSA Special Publication #33, ASA-CSSA-SSSA, Madison, WI.
  • Sibley A.M., Grassini P., Thomas N.E., Cassman K.G., Lobell D.B. (2014) Testing remote sensing approaches for assessing yield variability among maize fields. Agron J 106:24-32. LINK:
  • Cassman KG, Grassini P, (2013). Can there be a green revolution in Sub-Saharan Africa without large expansion of irrigated crop production? Global Food Sec. 2, 203-209.
  • Van Wart J., Grassini P., Cassman K.G. (2013) Impact of derived global weather data on simulated crop yields.. Global Change Biology 19:3822-3834. LINK:
  • Van Ittersum M.K., Cassman K.G., Grassini P., Wolf J., Tittonell P., Hochman Z. (2013) Yield gap analysis with local to global relevance - a review. Field Crops Research 143:4-17. LINK:
  • Van Wart J., Van Bussel L.G.J., Wolf J., Licker R., Grassini P., Nelson A., Boogaard H., Gerber J., Muelle N.D., Claessens L., Cassman K.G., Van Ittersum M.K. (2013) Reviewing the use of agro-climatic zones to upscale simulated crop yield potential. Field Crops Research 143:44-55. LINK:
  •  Grassini P., Yang H., Irmak S., Rees J., Burr C., Cassman K.G. (2012) Evaluation of water productivity and irrigation efficiency in Nebraska corn production. Extension Circular 105. University of Nebraska-Lincoln.
  • Grassini P., Yang H., Irmak S., Rees J., Burr C., Cassman K.G. (2012) Yield gaps and input-use efficiency of high-yield irrigated corn in Nebraska. Extension Circular 106. University of Nebraska-Lincoln.
  • Grassini P., Cassman K.G. (2012) High-yield maize with large net energy yield and small global warming intensity. Proceedings of the National Academy of Sciences (PNAS) 109:1074-1079. LINK:
  • Irmak S., Burgert M.J., Yang H.S., Cassman K.G., Walters D.T., Rathje W.R., Payero J.O., Grassini P., Kuzila M.S., Brunkhorst K.J., Van DeWalle B., Rees J.M., Kranz W.L., Eisenhauer D.E., Shapiro C.A., Zoubek G.L., Teichmeier G.J. (2012) Large scale on-farm implementation of soil moisture-based irrigation management strategies for increasing maize water productivity. Transactions of the ASABE 55:881-894.
  • Sadras V, Grassini P., Steduto P. (2011) Status of water use efficiency of main crops. In: The state of world's land and water resources for food and agriculture (SOLAW). FAO, Rome and Earthscan, London.
  • Grassini P., Thorburn J., Burr C., Cassman K.G. (2011). High-yield irrigated maize in the Western U.S. Corn-Belt: I. On-farm yield, yield-potential, and impact of management practices. Field Crops Res. 120:142-150.
  • Grassini P., Yang, H., Irmak S., Thorburn J., Burr C., Cassman K.G. (2011) High-yield irrigated maize in the Western U.S. Corn-Belt: II. Irrigation management and crop water productivity. Field Crops Res 120:133-141.
  • Cassman K.G., Grassini P., van Wart J. (2010) Global food security in a changing climate: crop yield trends and yield potential. In: Hillel D., Rosenzweig C. (Eds), Handbook of climate change and agroecosystems: impacts, adaptation, and mitigation. Imperial College Press, London, UK, pp. 37-51.
  • Grassini P., You J., Hubbard K.G., Cassman K.G. (2010) Soil water recharge in a semi-arid template climate of the Central US Great Plains. Agric. Water Manage. 97:1063-1069.
  • Grassini P., Yang H.S., Cassman K.G. (2009) Limits to maize productivity in Western Corn Belt: a simulation analysis for fully-irrigated and rainfed conditions. Agric For Meteor 149:1254-1265.
  • Grassini P., Hunt E., Mitchell R., Weiss A. (2009) Simulating switchgrass growth and development under potential and water limiting conditions. Agron J 101:564-571.
  • Grassini P., Hall A.J., Mercau J.L. (2009) Benchmarking sunflower water productivity in semiarid environments. Field Crops Res 110:251-262.
  • Grassini P., Indaco G.V., López Pereira M., Hall A.J., Trápani N. (2007) Physiological responses to temporary waterlogging during grain filling in sunflower. Field Crops Res 101:353-363.