During several growing seasons, the authors organized rounds of farm experimentation with three different crop species, in Nicaragua, Ethiopia and India. They applied a citizen science approach called tricot (for triadic comparisons of technologies). In tricot variety evaluation, each farmer plants seeds from a personalized test package of three varieties, which are randomly assigned from a larger pool of tested varieties. The authors kept track of seed varieties and the location of plots. But the experiments themselves were up to farmers, who generated data by planting a total of 12,409 plots. A simple ranking-based feedback format allows even farmers with low literacy skills to contribute their evaluation data through various channels, including mobile telephones.
The authors then linked the farmer-generated data via their geographic coordinates to agroclimatic and soil data. "We tested a novel method of statistical modelling to see if there is a link between climate and variety performance, to try to explain why certain varieties perform better than others," says Kauê de Sousa, one of the authors of the study. "The results were very positive. For our three countries, our models show that there is a very clear link between variety performance and climate – a single climatic variable can explain the behaviour of the varieties, and the results corresponded well with what we know about the stress tolerance of these varieties. We could also generate varietal recommendations for different agroclimatic zones."
How do these findings help farmers? The authors write that the farmer trials can improve variety recommendations as they are more targeted to local climates. They show that the recommendations generated by farmers improve those provided before by scientists. Also, in the future the information could be blended with seasonal climate forecasts to further improve the recommendations and can serve to create variety portfolios that diminish climate risk. “This study does not only confirm that our initial hunch was correct – citizen science can help farmers with climate adaptation. It also shows the enormous potential of citizen science in agriculture,” says Jacob van Etten. “It opens a whole new area of possibilities.”
Read the study 'Crop variety management for climate adaptation supported by citizen science' published in PNAS
Read the press release about the study on EurekAlert!
Part of this research was supported by cooperative agreement AID-OAA-F-14-00035, which was made possible by the generous support of the American people through the United States Agency for International Development (USAID). The research received financial support from McKnight Foundation (CCRP 16-098), the German Federal Ministry for Economic Cooperation and Development (BMZ/GIZ, Contract No. 81194988) and the Indian Council of Agricultural Research (ICAR, Annual Workplan). This work was implemented as part of the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS), which is carried out with support from the CGIAR Trust Fund and through bilateral funding agreements. For details please visit https://ccafs.cgiar.org/donors