Increase in starving populations and the environmental degradation due to the expansion of agricultural lands are both threats to global food security. We focus on small-scale farmers in Africa, who are the key to solving both problems. By simultaneously providing technical solutions to increase lowland rice productivity and scientific evidence of the impact of forest loss on rice production, this project aims to halt the negative cycle of unstable agricultural production and environmental destruction, and to demonstrate that sustainable food production systems can be transformed. Based on the practical outcomes obtained, we will contribute to the promotion of poverty reduction, improved nutrition, and sustainable agriculture in Africa by spreading the same approach.

Output 1. Development of advanced rice paddy field utilization technology that both improves productivity and reduces environmental impact

Focusing on the effect of P-dipping on shortening the lowland rice growing (waterlogging) period, we will demonstrate that the adoption of this technology is effective not only in increasing the rice yield with less P fertilizer, but also in reducing methane (20~30% reduction) generated under waterlogging conditions and increasing off-season crop production after rice harvest (20% yield increase). Methane is the main greenhouse gas (GHG) emitted from lowland rice paddy fields. For the off-season crops, we will use Brassica vegetables, a promising source of cash income and micronutrients, in collaboration with Output 2. The results obtained will be used to develop a technical manual for advanced paddy field utilization methods that increase the productivity of both paddy rice and backcrops while reducing the environmental burden.

Output 2. Development of technology to promote growth of vegetable and legume crops by soil microorganisms

We will utilize the filamentous fungus Colletotrichum tofieldiae (Ct), which is effective in promoting the growth of Brassica vegetables, as a future commercial technology to enhance the productivity of off-season crops. We will also use native rhizobia that have been selected by CNRE to enhance the yield of common bean (Phaseolus vulgaris). In addition, we will explore novel microorganisms that can be co-inoculated with these strains to create a synergistic effect. After repeated validation in farmers' fields, we will develop microorganism utilization technology that can increase yields of Brassica vegetables and legume crops by 20%.

Output 3. Establishment of dissemination methods for development technologies and evaluation of their impact on farmers' welfare statistics and land use

We will develop a new extension approach to effectively scale up production technologies such as P-dipping by identifying key influencers—including fertilizer retailers—who play a crucial role in information dissemination, and by elucidating the cluster effects that promote technology adoption as well as the social ties among farmers. In addition, we will clarify the effects of improved productivity and crop diversification in paddy fields on farmers’ welfare indicators and land use, as well as the role of market orientation and market functions in mediating these effects.

Output 4. Quantitative evaluation of the water source conservation of forests on rice production in the watershed

We will visualize how forests support stable production of rice paddy fields and play an essential role in sustainable food production by preventing sediment from flowing into downstream rice paddies and providing stable supplies of water and nutrients. Specifically, we will develop watershed attributes such as vegetation and topography for small watersheds with different levels of forest degradation, and construct a wide-area rainfall-runoff model based on temporal hydrological observations. The model will be used to analyze the risk of river flooding and drought, as well as changes in the amount of sediment and nutrients flowing into rice paddy fields, in order to quantify the impact of forest degradation on rice production and economic losses.

This project is an international collaborative research project led jointly by the Japan International Research Center for Agricultural Sciences (JIRCAS), the Malagasy Ministry of Agriculture and Livestock (MINAE) and the Malagasy Ministry of Environment and Sustainable Development (MEDD). Other participating organizations are the University of Tokyo, Kyoto University, Forestry and Forest Products Research Institute (FFPRI), University of Tsukuba, and  University of Yamanashi on the Japan side, and the National Center for Applied Research and Rural Development (FOFIFA), the Radioisotopes Laboratory of the University of Antananarivo (LRI), National Research Center for Environment (CNRE), and the National Nutrition Office (ONN) on the Malagasy side. Researchers from these organizations are leveraging their respective specializations to conduct joint research on Outputs 1–4 and create sustainable and diversified rice farming system that simultaneously achieves zero-hunger and zero-emission.