Our research on controlling potato late blight in Rwanda won a poster presentation at the 12th African Potato Association conference in Lilongwe, Malawi

The 12th African Potato Association's triennial conference, held in Lilongwe, Malawi, from June 27 to July 1, 2022, focused on "Harnessing potato and sweet potato innovations for resilient and healthier agri-food systems." This hybrid conference served as a premier event in Africa to showcase the potential of root and tuber crops for enhancing food and nutrition security, while also improving incomes for farmers and sellers. The Ministry of Agriculture & Food Security, the International Potato Center, and other partners jointly organized the conference.

The Attendance at this conference involved a competitive evaluation of abstracts submitted by 310 research organizations working on root and tubers. AGRIRESEARCH Organization, a youth-led research organization operating in Rwanda, was among the competing entities.

Our research aimed to evaluate the effectiveness of potato planting structures and combining preventive fungicides to control late blight in Rwandan potato crops. This research stemmed from the observation that potato production in Rwanda faces a significant challenge: high yield reductions, posing a threat to food security. Late blight is a major contributor to this problem, causing 25-50% crop damage in Rwandan highlands. Several factors exacerbate the disease pressure for example of Continuous planting on small plots without rotation leads to increased inoculum buildup in the soil, Disease transmission occurs through readily available, outdated potato varieties (97% of seeds come from informal sources, according to USAID, 2016), and Weather conditions with increased wet cycles in the northwestern potato-growing region favor late blight development (Muhinyuza et al., 2012).

Most farmers rely solely on two fungicides (Dithane M-45 or Ridomil) season after season. This, combined with improper chemical use, reduces seed resistance to late blight and increases costs. To address these issues, we sought to Increase genetic diversity for disease control by designing and evaluating optimal mixtures of potato varieties And Enhance on-farm productivity and climate change resilience by exploring alternative planting structures and fungicide combinations. Therefore, our study investigated the effectiveness of potato planting structures, fungicide combinations, and a new locally made fungicide, "GITENGE" (copper-based), for controlling late blight. While primarily designed for this purpose, GITENGE was not yet used by farmers.

The Results showed that the potato variety non-mixture system with a fungicide combination of one Ridomil spray followed by Gitenge proved most effective, with a tuber yield of 46.9 metric tons per hectare. Other treatments yielded 43.6 metric tons per hectare with Gitenge alone, 42.9 metric tons per hectare with Dithane M-45 alternating with Gitenge and 40.8 metric tons per hectare with Dithane M-45 alone respectively. These results clearly demonstrate the increased effectiveness of the variety non-mixture system with an appropriate combination of fungicides.

Growth & yield parameters data collection on our research

Competing with 310 organizations within the context of the conference was a valuable experience. Our research abstract, "Evaluating the effectiveness of potato planting structures and combining preventive fungicides to control late blight on potato crop in Rwanda," secured a place among the 170 selected research projects for poster presentation.

Abstract of our research topic submitted in the competition of 310 research organizations.

To be selected and attending The  12th African Potato Association conference was good experience and an opportunity for us, this conference provided a valuable platform for interaction with researchers worldwide, allowing us to gain valuable insights into potato research and explore potential solutions for climate change resilience. We presented our research to scientists and stakeholders across Africa and the globe, fostering networking, knowledge exchange, and initiating new collaborative studies on potato. Additionally, several international organizations expressed interest in collaborating with us to the next other researches. The conference proved to be much more than just a presentation opportunity. It was a catalyst for forging connections, igniting new ideas, and propelling our research forward. We returned to Rwanda energized and equipped with a broader perspective and valuable partnerships to tackle the challenges faced by Rwandan potato farmers.