By: Caroline Kolins and Dena Bunnel
When Tesfaye Tadesse was a boy in Debra-Elias, Ethiopia, he would walk two hours each morning to attend school. Many years later, his education journey would lead him to Kansas State University where he conducts research under the Feed the Future Innovation Lab for the Reduction of Post-Harvest Loss on alternative ways to protect grains from insect pests without using pesticides that are harmful to human health.
The United Nations Food and Agriculture Organization reports that as much as 1.3 billion tons of food are lost or wasted each year – equivalent to 24 percent of all food calories produced for human consumption. In Ethiopia, farmers often lose 20 to 30 percent of their harvest due to insects, rodents and improper storage and drying techniques. Even grain that is not directly lost may not be safe if it has been contaminated by fungal toxins or dangerous pesticide residues.
In Ethiopia, farmers often purchase or receive pesticides without knowledge of the substance or training on the proper use and disposal of the chemicals. Farmers use dangerous chemicals without proper protective gear and mix unknown chemicals together. It is common to see the same containers that once held potentially toxic chemicals re-used as drinking glasses or food storage containers. Tesfaye remembers growing increasingly concerned about the poor pesticide handling practices in his home country when he witnessed a participant in a local training carrying a test tube of Phosphine, a commonly used fumigant which will ignite when it interacts with air, without any protective gear or concern for potential reactions. This experience inspired his current research on inert dusts – mineral dusts that have little or no chemical toxicity – as safe grain protectant options for farmers. His dissertation research is testing Triplex and filter cake, two inert dusts that are industrial bi-products from detergent and aluminum sulfate production, respectively, and are locally available in Ethiopia. The two powders were tested on multiple insects with various concentrations on corn and wheat, two of Ethiopia’s most important grains. Filter cake in particular was found to be highly effective in killing stored product insects. Because these products are not dangerous to human health, there is no need for specialized training or protective gear, making it an easy, safe, and effective technology to protect stored grain in households.
For this research, Tesfaye set up experiments in a laboratory at Kansas State University that simulated grain storage containers by creating mini-versions with cement in a petri dish. His findings were recently published in The Journal of Stored Products Research (1). His next step is to test them in the field using the actual storage structures widely used in Ethiopia. He also plans to convert his standard measurements into non-standard measurements traditionally used in low-resource settings, like his home of rural Ethiopia. His greatest hope is that the results in the field will be as promising as the ones in the lab and that this method of preventing post-harvest losses will improve livelihoods through fewer losses and better incomes. Tesfaye will complete his PhD in grain science and industry this year, and he plans to return to Ethiopia and use this research to help Ethiopian farmers decrease their post-harvest losses.
1 Tadesse, T. M., and Subramanyam, B. 2018. Efficacy of filter cake and Triplex powders from Ethiopia applied to concrete arenas against Sitophilus zeamais. J. Stored Prod. Res. 76, 140-150.