Abstract
The majority of genetically modified (GM) crops are produced for livestock consumption, whereas minimal attention has been given to GM crops for direct human consumption. In South Africa, GM white maize has been grown for direct human consumption alongside GM yellow maize and conventional hybrid (CH) maize for livestock feed since 1999. Here we investigate yield differences between GM white, GM yellow and CH maize across 106 locations, 28 years, 491 cultivars, and 49,335 dryland and 9,617 irrigated observations in South Africa. GM maize increased mean yields over CH by 0.42 metric tons (Mt) ha−1 and reduced yield risk. We show that GM white maize increased yields by 0.60 Mt ha−1 and GM yellow maize by 0.27 Mt ha−1 compared with CH maize. GM yield gains were similar for dry and irrigated production. Our study highlights the potential impacts of growing GM grain crops for human consumption in African countries.
This is a preview of subscription content, access via your institution
Access options
Access Nature and 54 other Nature Portfolio journals
Get Nature+, our best-value online-access subscription
$29.99 / 30 days
cancel any time
Subscribe to this journal
Receive 12 digital issues and online access to articles
$119.00 per year
only $9.92 per issue
Buy this article
- Purchase on SpringerLink
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
Data availability
The data that support the findings of this study were provided by the South Africa ARC and are available from the corresponding author upon request and with approval from the ARC.
Code availability
The Stata v.15 code that supports the findings of this study is available from the corresponding author upon request.
References
Smyth, S. J., Kerr, W. A. & Phillips, P. W. B. Global economic, environmental and health benefits from GM crop adoption. Glob. Food. Sec. 7, 24–29 (2015).
Brookes, G., Taheripour, F. & Tyner, W. E. The contribution of glyphosate to agriculture and potential impact of restrictions on use at the global level. GM Crops Food 8, 216–228 (2017).
Klümper, W. & Qaim, M. A meta-analysis of the impacts of genetically modified crops. PLoS ONE 9, e111629 (2014).
Xu, Z., Hennessy, D. A., Sardana, K. & Moschini, G. The realized yield effect of genetically engineered crops: US maize and soybean. Crop Sci. 53, 735–745 (2013).
Lusk, J., Tack, J. & Hendricks, N. Heterogeneous Yield Impacts from Adoption of Genetically Engineered Corn and the Importance of Controlling for Weather https://doi.org/10.3386/w23519 (National Bureau of Economic Research, 2017).
Qaim, M. Bt cotton, yields and farmers’ benefits. Nat. Plants 6, 1318–1319 (2020).
Ahmed, A., Hoddinott, J. F., Abedin, N. & Hossain, N. Z. Economic and Health Impacts of Genetically Modified Eggplant: Results from a Randomized Controlled Trial of Bt Brinjal in Bangladesh https://doi.org/10.2499/p15738coll2.133412 (IFPRI, 2019).
Ahmed, A. U., Hoddinott, J., Abedin, N. & Hossain, N. The impacts of GM foods: results from a randomized controlled trial of Bt eggplant in Bangladesh. Am. J. Agric. Econ. https://doi.org/10.1111/ajae.12162 (2020).
Zilberman, D., Holland, T. & Trilnick, I. Agricultural GMOs—what we know and where scientists disagree. Sustainability 10, 1514 (2018).
Gastrow, M., Roberts, B., Reddy, V. & Ismail, S. Public perceptions of biotechnology in South Africa. S. Afr. J. Sci. 114, 2017–0276 (2018).
Qaim, M. & Zilberman, D. Yield effects of genetically modified crops in developing countries. Science 299, 900–902 (2003).
Global Status of Commercialized Biotech/GM Crops: 2018 ISAAA Brief 54-2018 https://isaaa.org/resources/publications/briefs/54/default.asp (ISAAA, 2018).
Shew, A. M. et al. Are all GMOs the same? Consumer acceptance of cisgenic rice in India. Plant Biotechnol. J. 14, 4–7 (2016).
Gonsalves, C., Lee, D. R. & Gonsalves, D. The Adoption of genetically modified papaya in Hawaii and its implications for developing countries. J. Dev. Stud. 43, 177–191 (2007).
Gouse, M., Pray, C. E., Kirsten, J. & Schimmelpfennig, D. A GM subsistence crop in Africa: the case of Bt white maize in South Africa. Int. J. Biotechnol. 7, 84–94 (2005).
Gouse, G. GM maize as subsistence crop: the South African smallholder experience. AgBioForum 15, 163–174 (2012).
Shi, G., Chavas, J.-P. & Lauer, J. Commercialized transgenic traits, maize productivity and yield risk. Nat. Biotechnol. 31, 111–114 (2013).
Genetically Engineered Crops: Experiences and Prospects—New Report http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=23395 (NASEM, 2016).
Adenle, A. A., Morris, E. J. & Parayil, G. Status of development, regulation and adoption of GM agriculture in Africa: views and positions of stakeholder groups. Food Policy 43, 159–166 (2013).
Lobell, D. B. et al. Prioritizing climate change adaptation needs for food security in 2030. Science 319, 607–610 (2008).
Serdeczny, O. et al. Climate change impacts in sub-Saharan Africa: from physical changes to their social repercussions. Reg. Environ.Change 17, 1585–1600 (2017).
Rippke, U. et al. Timescales of transformational climate change adaptation in sub-Saharan African agriculture. Nat. Clim. Change 6, 605–609 (2016).
Travis, W. R. Mapping future crop geographies. Nat. Clim. Change 6, 544–545 (2016).
General Household Survey http://www.statssa.gov.za/?p=9922 (STATSA, 2016).
Walker, N. J. & Schulze, R. E. Climate change impacts on agro-ecosystem sustainability across three climate regions in the maize belt of South Africa. Agric. Ecosyst. Environ. 124, 114–124 (2008).
Kruger, M., Van Rensburg, J. B. J. & Van den Berg, J. Perspective on the development of stem borer resistance to Bt maize and refuge compliance at the Vaalharts irrigation scheme in South Africa. Crop Prot. 28, 684–689 (2009).
Chavas, J.-P., Shi, G. & Lauer, J. The effects of GM technology on maize yield. Crop Sci. 54, 1331 (2014).
Greyling, J. C. & Pardey, P. G. Measuring maize in South Africa: the shifting structure of production during the twentieth century, 1904–2015. Agrekon 58, 21–41 (2019).
Acknowledgements
We acknowledge and thank the South Africa Agricultural Research Council–Grain Crops Institute (ARC-GCI) for providing access to the data used in this study. All opinions expressed in this paper are the authors’ and do not necessarily reflect the policies and views of ARC-GCI.
Author information
Authors and Affiliations
Contributions
A.M.S., J.B.T., L.L.N., P.C. and S.M. conceptualized the study and performed research. P.C. and S.M. collected and synthesized data. A.M.S., J.B.T. and L.L.N. designed the study. A.M.S. and J.B.T. analysed data. A.M.S., J.B.T. and L.L.N. wrote the manuscript. A.M.S., J.B.T., L.L.N., P.C. and S.M. revised the final manuscript.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing interests.
Additional information
Peer review information Nature Food thanks G. Slafer, S. Smyth and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary information
Supplementary Information
Supplementary Tables 1–3 and Fig. 1.
Rights and permissions
About this article
Cite this article
Shew, A.M., Tack, J.B., Nalley, L.L. et al. Yield gains larger in GM maize for human consumption than livestock feed in South Africa. Nat Food 2, 104–109 (2021). https://doi.org/10.1038/s43016-021-00231-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/s43016-021-00231-x
This article is cited by
-
Haploid-Double Haploid Technology for Accelerating Hybrid Development in Maize (Zea mays L.)
Tropical Plant Biology (2023)
-
Lessons learned from the introduction of genetically engineered crops: relevance to gene drive deployment in Africa
Transgenic Research (2022)
-
Global maize production, consumption and trade: trends and R&D implications
Food Security (2022)
-
Biotechnology for African food security
Nature Food (2021)
