Uganda’s rapidly expanding urban population has developed a taste for french fries, sending the demand for potatoes skyrocketing and making the vegetable the country’s fifth largest crop after bananas, cassava, maize and sweet potato.
But most of the Ugandans wolfing down french fries have no idea that the nation’s potato farmers are spraying their crops with chemicals up to six times each season in order to fend off late blight disease (LBD). The devastating plant disease, caused by the pathogen Phytopthora infestans, is the primary factor limiting national potato production. Unless they spray chemical fungicides, farmers risk getting zero yields , which means urban Ugandans would have to go without their new favorite street food.
But a lack of french fries is small potatoes when compared to how all of this spraying affects the subsistence cultivators who produce Uganda’s potato crop. These farmers use a full two-thirds of their input investments on chemicals — money that could otherwise be used on fertilizers or quality seeds. There's also the human and environmental health issue. A 2015 study published in the Biomed Research International Journal showed that due to low literacy levels, a full 91 percent of the farmers do not understand the toxicity information labels on their chemical packages.
Thankfully, a solution may be at hand. Scientists at Uganda’s National Agricultural Research Organization (NARO) and the International Potato Center (CIP) have developed a new potential variety named 3R Vict 1. This new potato is developed from a Victoria variety that is preferred by farmers, but also the most susceptible to LBD.
The Vict 1 is a result of isolating three genes of late bight resistance in a wild potato variety and transferring them to the Victoria potatoes through genetic engineering. According to Dr. Alex Barekye, a senior scientist at NARO, the genes were found in a closely related wild potato and could have been transferred through conventional breeding. But that takes time.
“We chose genetic engineering over conventional breeding because of its precision and its ability to keep the farmer-preferred variety qualities intact,” Barekye said. “It would take a very long time, over 20 years, to come up with a late blight resistant variety through conventional means.”
Early results have been promising.
“During three seasons of confined field trials at the Kacwhekano Zonal Agricultural and Development Research Institute in Kabale, 3R Vict 1 showed full resistance to late blight disease and did not need a drop of fungicide,” Dr. Andrew Kiggundu, the principal investigator of NARO’s potato project, said.
New variety raises farmers’ hopes...
Friday Herbert is a potato farmer who participated in the trial at Kachwekano Village. He finds the promise of a potato that does not need spraying tantalizing.
“We always spray our fields with pesticides if we are to realize any yields,” he said. “Chemicals are expensive; sometimes we can only afford to spray once or twice. We are eagerly waiting for this variety to be given to us.”
In Herbert’s potato garden, patches of blighted leaves were clearly visible even after he had sprayed. Evidence of the local farmers’ spraying culture is seen in his aging knapsack sprayer and the empty sachets of chemical fungicide that litter his homestead.
Although he does not yet have access to this new variety, Herbert already knows how he would spend the money he currently uses on chemicals.
“The money I save from the chemical expenditure when I begin growing this new potato variety will help me buy more land to expand my potato production, buy cows, and pay school fees for my four children,” he said.
… but causes no worry for a chemical vendor
But potential gains for farmers like Herbert could mean a loss to chemical vendors like Alex Masaba, who sells fungicides to potato and tomato farmers. Masaba, however, doesn’t seem worried that a new potato variety would put him out of business.
“As long as agriculture continues to encroach on the habitats of insects and other microorganisms, pests will come to crops and chemicals will be sold,” he said.
Masaba said that many farmers are also resistant to change their ways, pointing to the fact that he sells two different tomato variety seeds at his shop — one that is resistant to a certain type of wilt and the other that is not.
“Farmers come here and they ask for either variety or both. Even when scientists release the new late blight resistant potato, I will still sell my chemicals because some farmers will still continue to plant susceptible varieties for whatever reason they have,” he said.
Masaba may be able to find out if his theory holds as early as 2020, when the 3R Vict 1 trials are completed and analyzed. In addition to further testing for disease resistance, scientists are required to provide data on the comparative performance of the Vic.1 and the conventionally bred Victoria variety. Abel Arinaitwe, who oversees the trials, explained that part of the process involves spraying both the late blight resistance potato and the susceptible variety with fungicides.
“We are interested in comparing the yields of the two and it can only be accurate if we subject them to similar treatments,” Arinaitwe said, adding that some fungicides have growth boosters that would make it difficult to compare data from the two varieties if only one had been sprayed. Other plots will remain without the spraying to demonstrate the responses of the two varieties to a late blight attack.
The Uganda potato trials are being conducted under the watchful eye of the National Biosafety Committee (NBC), whose chairman, Dr. Charles Mugoya, said the agency serves as “a watchdog to ensure every process is strictly adhered to according to laid down standard procedures.”
Dr. Mugoya said that Uganda, with 20 years of handling GM-related research processes and its recently-passed biosafety bill, is ready to see its first GM crops in farmers’ gardens.
“[The Biosafety Bill] will help facilitate our role in ensuring consumers get a product that will not only address the problem it is meant to address, but also a product safe for us and the environment,” he said.
At the site of the third trial, in Bunginyanya, Arthur Wasukira is monitoring environmental factors in addition to growth characteristics like the number of days between planting and sprouting, growth period, insect counts, and the number of tubers. The data generated here will be part of a dossier aimed at getting the variety approved for commercial release.
“When it comes to GMOs, people tend to focus more on the harm it may cause to the environment not on how it may improve the environment,” Wasukira said.
While the regulation process plays out, farmers are left waiting for a potato variety that Dr. Eric Magembe, a molecular biologist at CIP who took part in the trials at Rwebitaba, says will be of great benefit to them.
“Our key beneficiaries are the resource poor farmers in Uganda and elsewhere in Africa where potato is grown as a source of food and income,” he said. “At CIP, we seek to reduce poverty and achieve food security on a sustained basis in developing countries like Uganda through scientific research.”
Friday Herbert, the subsistence farmer in Kachwekano village, hopes that by 2020 he will, for the first time in his potato growing life, plant a potato that does not need to be sprayed.
He envisions standing by his green leafy potato field, admiring the sight of purple potato flowers in his four-acre garden near the popular tourist destination Lake Bunyonyi. As he overlooks the field with no burnt patches of blight evidence, he will do so without having to smell any chemicals and with extra money saved safely in his pockets.
Isaac Ongu is a Uganda-based journalist who specializes in agriculture.