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Functional Plant Biology Functional Plant Biology Society
Plant function and evolutionary biology
REVIEW

The pros and cons of GM crops

Jennifer A. Thomson
+ Author Affiliations
- Author Affiliations

Department of Molecular and Cell Biology, University of Cape Town, South Africa. Email: jennifer.thomson@eject.co.za

Functional Plant Biology 45(3) 297-304 https://doi.org/10.1071/FP17031
Submitted: 7 March 2017  Accepted: 5 September 2017   Published: 2 October 2017

Abstract

The year 2015 marked the 20th year of the commercialisation of genetically modified (GM) crops. During the period from 1996 to 2014, the global hectarage of these crops increased 100-fold, making it the fastest adopted crop technology in recent times. The overall economic gains from these crops have been estimated to be USD133.4 billion over the period from 1996 to 2013, and have been divided roughly 50% each to farmers in developed and developing countries. The environmental benefits include contributing to the practice of minimal till agriculture and a decrease in the use of pesticides. But what are the downsides of this technology? In this review I look at some of the problems related to weeds becoming resistant to glyphosate (the main ingredient that is used on herbicide tolerant crops), how these can be overcome and whether glyphosate can cause cancer. I also discuss the problem of insects becoming resistant to the toxins that are used in insect resistant crops and how these are being addressed. I look at what scientists around the world are saying on this topic and then consider GM crops that are in the pipeline of benefit to developing countries and whether any of these are likely to be commercialised in the foreseeable future.

Additional keywords: banana, cassava, cowpea, eggplant, herbicide, insect, maize, virus.


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