The global acreage of Genetically Modified (GM) crops had reached 448m acres by 2014, growing at 4 per cent a year from an initial 4.3m acre in 1996, according to the International Service for the Acquisition of Agri-Biotech Applications (ISAAA).
The world is however still working to measure the impact of GE technology on the surrounding vegetation.
The situation in Kenya is not different either. As the country roll its sleeves to embrace genetically engineered crops like Bacillus thuringiensis (Bt) maize which is being piloted by the Kenya Agricultural and Livestock Research Organization (KALRO), local experts are divided on whether this new agricultural technology is a threat or not to biodiversity as compared to the use of pesticides and herbicides.
Reduction in pesticides use by farmers
Dr. Lusike Wasilwa, the Head of Crop Systems at KALRO explains that adoption of GE crop like Bt which is engineered to produce unique protein that choke hostile pests like maize stalk borer estimated to be lowering the country’s maize production by a whopping 400,000 tonnes per year will drastically reduce the use of pesticides on farms.
The researcher’s argument is supported by a 2014 peer review study titled ‘Meta analysis of the impact of genetically modified crop’ and published in the PLOS One Journal which illustrates a 37 percent reduction in pesticide use by farmers in South Africa since the country adopted GE crops in 1998. Dr Lusike said that apart from reducing contamination of water bodies depended upon by both flora and fauna for survival, excessive use of pesticides on farm acidify soils and kill soil forming micro-organisms, hence rendering it infertile to support vegetation.
The study by the Harvard University School of Fine Arts and Science, GMOs and Pesticides: helpful or harmful, seems to qualify Dr.Lusike’s argument about the effectiveness of plant-incorporated-pesticides (PIPs) in reducing the use of pesticides amongst farmers. The study shows that the rollout of Bt cotton, maize and soybeans saw the use of pesticides by US farmers fall from a high of 0.2kg/ha in 1995 to zero in 2010.
Another study assessing the global economic and environmental impacts of biotech crops for the first seventeen years (1996-2012) of adoption showed that the technology has reduced pesticide spraying by 503million kilos while reducing the environmental footprint associated with pesticide use by 18.7 percent
The technology has also significantly reduced the release of greenhouse gas emissions from agriculture, equivalent to removing 11.9 million cars from the roads.
Prevent unnecessary killing of pollinators
Furthermore, Dr Lusike praised the precision of PIP saying that it prevents unnecessary harm of other organisms which may be beneficial to vegetation.
She explained that unlike conventional pesticides which end up killing pollinators like bees and butterflies, Pest incorporated plants like Bt varieties are engineered to produce unique proteins which target specific pests.
Although various research like the one conducted by the Pesticide Network Action (PANNA) dubbed GE corn and sick honey bees tend to attribute the dwindling number of bees in the world to the mushrooming GE technology, Lusike is quick to dismiss them, asserting that even before the introduction of GE crops, bees were dying at an alarming rate.
While the introduction of GE pest resistant crops may have reduced the impact of chemical pesticides on environment, most researchers agree that GE herbicide resistant crops like Roundup pose more danger than good to environment.
A researcher Wanjiru Kamau who doubles up as the Spokesperson for Kenya Biodiversity Coalition explains that when herbicide resist crop grow in other field, it is difficult to be eliminated due to its resistant trait, forcing farmers to use more herbicides.
She for instance explained that Roundup canola, herbicide resistant variety which was introduced in US, Canada and Australia two decades ago has found its way in other farms, dominating primary crops grown, and thereby forcing farmers to use more herbicides with the hope of killing it. She explained that increase in herbicide use among farmers to kill such ‘super weeds’ is likely to contaminate soils, water and air, threatening biodiversity.
Her arguments seems to be in sync with the Harvard School study which illustrates a sharp rise in glyphosate herbicides used in the production of bt maize, cotton and soybeans in the US since 1996, when the GMO crops were first grown commercially.
The graphical presentation of the use of glyphosate herbicides by farmers in the country shows a rise from 0.6kg/ha to 2.0kg/ha in cotton, 0.6kg to 1.6kg/ha in corn and 0.6kg/ha to 1.0kg/ha in soybeans by 2007.
The Harvard School study blame this increase in use of herbicides to emergency of more superior weeds which come as result of weediness- a condition where herbicide resistant crop establish itself as a weed in other crop field and possible cross breed between GE herbicide crop and compatible weeds
An Echo Watch study in Mississippi’s highly fertile agricultural delta region found 75 percent of roundup herbicide by Monsanto in the air and rain test samples, illustrating just how GE herbicides crops can be harmful to the environment.
The above sentiments are however disputed by a study in the Nature, a weekly international Journal on science, which insists that herbicide-resistant GM crops are less damaging to the environment than conventional crops grown at industrial scale.
A study by PG Economics, a consulting firm in Dorchester, UK, found that the introduction of herbicide-tolerant cotton saved 15.5 million kilograms of herbicide between 1996 and 2011, a 6.1percent reduction from what would have been used on conventional cotton. GM crop technology delivered an 8.9 percent improvement to the environmental impact quotient — a measure that considers factors such as pesticide toxicity to wildlife
The question of whether GE crops are able to cross breed with other conventional crops is a concern especially among environmentalists. Wanjiru explains that since the- a UN policy guideline on GMO signed in 2003 by 168 countries, Kenya included only allows commercialization of non sterile GE seeds, uncontrollable cross breed via pollination which is likely to run more plants into extinction is inevitable.
She explained that although the world is yet to document a case where GE crop pushed primary crops into extinction, superior traits that characterize GE crops like disease, drought and weed resistance offer them a competitive advantage to outgrow primary plants, thereby causing a genetic disruption in the ecosystem.
Supporting Wanjiru’s sentiments is a FAO study titled health and environmental impact of transgenic crops researchers which explains that gene flow from non sterile GM crops is possible through cross pollination with wild relatives.
Although this is advantageous for agriculture as farmers are likely to harvest hybrid crops with resistant traits like herbicide pesticide, drought among others, this gene flow is catastrophic for wild vegetation.
A 2011 GMO journal report shows that 75 percent of plant genetic diversity has been lost since 1900 and the introduction of GMO crops only helps to worsen the situation.
Although researchers are pulling in different sides on this topic, it is clear that the GM technology in crops is less harmful to biodiversity compared to the use of chemical pesticides and herbicides. However, as Kenya prepare to embrace GMOs, local researchers and regulators must tighten scrutiny to capture negative health and environmental effects that come with this technology.