The CGIAR, formerly the Consultative Group on International Agricultural Research, was established in 1971 to support investments in research and technology development geared toward increasing food production in the food-deficit countries of the world. Japan has cooperated with the CGIAR since becoming a member in 1972 and has made significant contributions in terms of both financial and human resources. In 2021, the CGIAR celebrates its 50th anniversary. This Special Issue brings together the contributions of Japan and Japanese researchers to sustainable food system transformation. It includes a review article on CGIAR’s international agricultural research and the role of Japan. There are 14 review papers from individual CGIAR Research Centers specialized in their respective fields, ranging from crops, livestock, forestry, fisheries, and natural resource management to policies, and an article from the Japan International Research Center for Agricultural Sciences (JIRCAS) that has long-term collaboration with the CGIAR. This introductory paper will briefly provide the background and rationale for this Special Issue and a short introduction of the papers presented herein.

For the past 50 years, agricultural research has contributed significantly to improving agricultural productivity for global food and nutrition security. The CGIAR, formerly the Consultative Group for International Agricultural Research, has been at the center of this effort. Accordingly, the orientation of CGIAR activities have profoundly changed over time from crop productivity improvement to broadened agendas, such as biodiversity conservation, environmental protection, and policy-related efforts. In parallel with the evolution of research orientation, the CGIAR also underwent operational reorganization. As the global food systems become more and more interconnected, and with global concerns about agriculture’s contribution to overstepping the planetary boundaries and driving climate crises, the CGIAR has tried to consolidate operations among the CGIAR Research Centers to address research needs of smallholder farmers in the 21st century. This review contextualizes the evolving role of the CGIAR vis-à-vis global challenges with reference to some highlights of Japan’s contribution in each of the following periods: the 1970s; the 1980s-1990s; the 2000s-2010s; and onwards. This exercise can contribute to understanding the drivers affecting the global food systems in retrospective and subsequently deriving foresights for future directions of the food system transformation.

The aim of this review was to give an overview regarding key points of potato germplasm enhancement associated with the International Potato Center and its global research-for-development partners including feedback from technology and germplasm recipients. Highlights were addressed on the participation by Japanese scholars to CIP. Also, specific impacts were raised on the Japanese research contribution on potato research for technology application and development for the partner countries by co-working with key Japanese organizations. Special reference was made to research on genetic underpinnings and technology development for enhancing the introgression and incorporation of traits that were not available in the primary potato breeding pools. The use of genetic engineering was also judged and in particular for its potential to address global uses. Future outlook was also provided for hinting Japanese participation to the international agriculture.

In this study, we explore the global shifts in research priorities and strategies with respect to Plant Genetic Resources (PGR) over a period of nearly 3 decades and also look at changes in donor strategies over the same period, with specific reference to Japanese support to PGR work. We conducted a quantitative text analysis based on reports published by Bioversity International, a leader in PGR issues, and looked at changes in the frequency of appearance of certain terms and words over a 22-year period (1998-2020), divided into six phases. Results show that over the period, Bioversity International’s focus transitioned from an emphasis on collection of genetic resources and conservation in genebanks to conservation through sustainable use across generations. This evolved further to “food” -centered approaches. More recently, the emphasis is shifting to “food system” approaches with emphasis on the linkages between agriculture, environment and nutrition. The priority issues of the organization at the different phases are presented. Over the same period, Japanese government investment strategies have shifted from supporting PGR collection work to building capacity of researchers (in both source countries and Japan) and creating more benefits from PGR including nutrition, health and economic benefits to local societies who are the keepers of the PGR. The involvement of Japanese researchers, including the main author, in the various research activities characteristic of the different phases of the transition is presented. In the current global shift towards food systems approaches where the linkage of agriculture, nutrition, and the environment is emphasized, and the involvement of the private sector encouraged, partnerships with resource rich counters will be considered important in PGR activities in the future.

The International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) is one of 15 CGIAR centers and takes part in agricultural research and development in the most marginal regions of the world. Over the past 40 years, many Japanese scientists/projects have worked towards the improvement of crop production and betterment of livelihoods in the semi-arid tropics in both in Asia and Africa, some of which were supported by the Japanese Government and/or implemented by Japan International Research Center for Agricultural Sciences. In this paper, we review the significant scientific contributions of Japanese scientists to ICRISAT’s goals for each grand research theme.

Cowpea is a staple food crop and a primary source of protein for millions of people in developing countries. Although the crop is primarily cultivated for its mature grains, immature green pods and young green leaves can be consumed as a vegetable. The International Institute of Tropical Agriculture (IITA) was established in 1967; the organisation’s extensive research has developed many improved varieties of most staple food crops to benefit people across Africa. For example, more than 100 IITA-bred materials and numerous germplasm lines of cowpea from the Genetic Resource Center (GRC) of IITA which is a mandate crop have been distributed across sub-Saharan Africa. Currently, IITA GRC houses one of the largest global cowpea collections of over 17,000 accessions from 89 countries. Here, we review the diverse approaches undertaken in cowpea research to evaluate the wide genetic resources of IITA for the development of new varieties and their successful dissemination. Notably, Japanese scientists have made constructive contributions to the progress in cowpea research at IITA over the past 50 years. Finally, in terms of research for development, collaborative measures among various national and international stakeholders for the appropriate delivery and social implementation of research achievements in the future are discussed.

International Center for Tropical Agriculture (CIAT) has a long history of collaboration with Japanese institutions to develop improved crop varieties and adopt agricultural technologies with pioneering approaches for farmers’ benefit. Since 1972, Japan has enjoyed a long history of successful cooperation with the CGIAR (formerly the Consultative Group on International Agricultural Research) after becoming its 22nd Member to meet global challenges such as climate change affecting agriculture and food systems in diplomacy through Japan’s advanced science and technology. This long-standing collaboration adopts agricultural technologies developed in Japan and promotes agricultural innovation through cutting-edge technologies such as remote sensing for Internet of Things (IoT) and Artificial Intelligence (AI) that will provide novel solutions to the agriculture and food sectors in the tropics. Nowadays, it is presumed that this approach to data-driven agriculture realization will help establish a sustainable agroecosystem with increased agricultural productivity and sustainability by adapting or mitigating the effects of climate change and efficient use of natural resources and establishing a sustainable food value chain. This review highlights the research collaborations and new opportunities on advanced breeding technologies and digital innovations towards data-driven agriculture. In conjunction, we present a potential collaborative research between CIAT and Japan, prioritizing the current and future challenges in agriculture and food systems.

In the past 10 years, Japanese scientists have played a leading role in research for development in Africa Rice Center for pre-breeding, breeding, agronomy and post-harvest research which cover the biophysical aspects of the whole rice value-chain. This paper summarizes the related achievements of the center in situation and scenario analyses, varietal development, decision support tools, good agricultural practices and component technologies, land expansion for rice in lowland and improvement of water management, and post-harvest technologies. Although rice production of sub-Saharan Africa (SSA) has been increased, the situation of rice self-sufficiency in SSA has been getting worth due to faster increase of consumption than that of production. More efforts exploiting the new opportunity of One CGIAR and partnerships with governments, advanced institutes, national agricultural research systems and private sector should be made.

This paper reviewed the contributions of Japan to rice research through its partnership with the International Rice Research Institute (IRRI), which started in 1960. Japanese scientists were seconded to work at the IRRI headquarters or hired as full-time staff to conduct rice research in the fields of breeding, pathology, physiology, agronomy, and social sciences. Among them is Dr. Akira Tanaka who played a key role in the development of IR8, a rice variety credited for paving the way for the first Green Revolution. To disseminate research outputs from agronomic research on rainfed rice in Asia to farmers, IRRI developed an ICT-based decision support systems (i.e. weather-rice-nutrient integrated decision support system or WeRise) which are ideal platform to enable farmers to access database from various fields of rice research. These web-based technologies are also accessible through mobile devices. Web-based technologies can help accumulate big data that can be used to promote data-driven solutions and enable informed decision-making to help rice farmers adapt to current and future climate. Analysis of big data from various web-based technologies is still a researchable area where IRRI and Japan can work together to exploit valuable information from past researches and further contribute to sustainable development through rice research.

The International Maize and Wheat Improvement Center (CIMMYT) aims to improve human livelihoods, especially smallholder farmers’ livelihoods, through wheat and maize production mainly in the developing world. The first Japanese person to work at CIMMYT was an intern in 1970 according to existing CIMMYT documents. Since then, at least 10 interns or mid to long-term visiting students and 14 appointed or visiting researchers from Japanese institutes have worked on wheat and maize research at CIMMYT. Some Japanese board members and one Japanese Director General also contributed to the direction of CIMMYT’s research. i The Japanese researchers and intern students have contributed greatly to CIMMYT research and to world food production. The research includes maize germplasm genebank, rapid breeding/doubled haploid technology for wheat, durable disease resistance in wheat, wheat wild relatives for heat/drought tolerance and a new trait of biological nitrification inhibition and wheat fusarium head blight resistance. The outlook for global wheat and maize supply has not been optimistic and will become worse in the future due to an increasing world population, the impacts of heat and drought and the spread of new diseases caused by climate change. The scientific achievements left by Japanese scientists at CIMMYT can play an important role in mitigating these problems.

The Japan International Research Center for Agricultural Sciences (JIRCAS) working with partners such as CGIAR and its research centers, has made notable progress in creating farming solutions directed at the needs of poor farmers worldwide. This review discusses two critical achievements—development and deployment of differential systems for blast study in rice and biological nitrification inhibition (BNI). Both achievements were initiated from basic studies. Results of the research guide crop improvement programs designed to introgress rice blast resistance and BNI into target crops. Both works clearly highlight that collaboration of scientists are key to the success. The wide research networks of JIRCAS and CGIAR are effective at establishing partnerships which can tackle the complexity and geographic scale of challenges in agricultural research. CGIAR’s strong presence in regions where problems occur, rich genetic resources, and strong genetic improvement programs are crucial to effective research-for-development activities to achieve agricultural sustainability. CGIAR–JIRCAS partnerships should be strengthened to bringing the benefits of science to the world’s poor farmers.

In the arid regions of the world, maintaining economic and efficient crop production has been among the most critical challenges. In this context, International Center for Agricultural Research in the Dry Area (ICARDA) has been leading in research-for-development for improved management of scarce water and land resources in the arid regions. In the new framework of the One CGIAR, the role of ICARDA will be more indispensable as climate change will make considerable negative impact on water resource availability and land sustainability in the dry areas. This review covers selected research works pursued in irrigated, rainfed and agro-pastoral systems in cooperation with Tottori and other Japanese Universities which represent longest history of cooperation between ICARDA and Japan. The review is structured into sub-sections summarizing joint research on supplemental irrigation (SI) for wheat cultivation to optimize water productivity in semi-arid region of West Asia and North Africa (WANA), and rehabilitation of Jordan’s degraded agro-pastural lands with micro water harvesting technology. Joint ICARDA and Japanese Universities’ research enhanced knowledge on the various adaptation technologies’ effects on the soil-water-plant relationships, which supported the development of tailored solutions and scaling strategies. The results are internationally recognized as contributions to coping with scarce water resources and combating land degradation in arid and semi-arid environments.

Over the past four decades, IFPRI Japanese Researchers (IFPRI-JR) significantly contributed to the knowledge advancement for various agrifood system issues in ways that are central to IFRRI’s mandates and complementary to the whole CGIAR system. This paper summarizes IFPRI-JR’s key knowledge work, its evolution over time, and its collective contributions. In earlier years especially up to the 2000s, various policy and market analysis tools were applied to agricultural policy reforms and price policies in Japan and elsewhere. More recently, to respond to the food crisis in 2007-08, IFPRI-JR’s research contributed to building empirical evidence on agrifood system policy issues in developing countries, including identification of key market failures and the appropriate role of the public sector in public goods provision in the presence of externalities and economies of scale. Over time the analytical scope expanded to institutional issues on resource management and markets, human capital formation, gender issues, agrifood system transformation, food and nutrition security. Finally, promising Japanese technologies and know-how were (i) identified for sustainable agrifood system development, and (ii) transferred to developing countries in the field of global nutrition security and their effectiveness shown. Collectively, IFPRI-JR have a long track record of addressing emerging as well as long-term structural issues, in both Japan and the world at large.

Livestock plays an important role in the livelihoods of livestock farmers of developing countries through the provision of food, income sources, and assets. The International Livestock Research Institute (ILRI) has led global efforts on livestock research in developing countries, mainly in South and Southeast Asia and sub-Saharan Africa, and contributed to poverty alleviation and improvement of the health of people. During ILRI’s over 50-year history, its research priorities and orientations have evolved from animal breeding, production and health to approaches addressing various risks faced by resource-poor livestock farmers. This review highlights the research work implemented by three Japanese scientists, who respectively evaluated or proposed innovative solutions to distinctive risks faced by livestock, agricultural farmers, and consumers in developing countries. They are namely, (1) Index-Based Livestock Insurance (IBLI) to counter climate change risks, (2) mobile money to livelihood risks, and (3) participatory risk analysis to food contamination. This review then identifies and discusses areas of further research needed to improve the livelihoods of livestock farmers, then concludes by calling for international collaboration.

The climate crisis highlights the importance of forests in both mitigating and adapting to climate change, as well as in supporting the UN’s Sustainable Development Goals (SDGs). To promote the better understanding and valuing of the critical role forests play, and to develop holistic approaches to protecting and maintaining them, the Center for International Forestry Research (CIFOR) has adopted the mission “to bring scientific knowledge to bear on major decisions affecting the world’s tropical forests and the people who depend on them”. This paper highlights an important topic in CIFOR’s research portfolio – forests’ diverse roles in climate change mitigation and adaptation and how forest governance ensures the equitable and sustainable wellbeing of people, both locally and globally. As one of the founding donor countries of CIFOR, the Government of Japan has consistently supported CIFOR’s research through Japanese scientists collaborating in research projects and/or serving as members of CIFOR’s Board. This paper, therefore, specifically highlights research projects funded directly by the Government of Japan, in particular.

Fisheries research and development challenges have diversified significantly as we entered the 21^st century. The 2030 Agenda for Sustainable Development demands that agriculture research communities take more holistic approaches towards addressing global issues, such as poverty alleviation, environmental conservation, and food and nutrition security. There remains a growing need for considering both fisheries and fishing communities as part of social-ecological systems. In this paper, we review how over the last two decades WorldFish has framed its research, with an emphasis on small-scale fisheries in low- and middle-income countries, and the contribution Japanese researchers have made in topics relevant to the Sustainable Development Goals (SDGs): sustainable fisheries management and conservation; resource access and benefit-sharing; and food and nutrition security. Research in the past has shown collaborative forms of natural resource governance, social inclusion and gender equity play a critical role in ensuring food production translates to income and livelihoods outcomes, and to food and nutrition security in low- and middle-income country contexts. To fulfill its potential in a wider range of SDGs, future research needs to consider fisheries and aquaculture as an integral component of “food systems”, encompassing production systems, their environments, post-harvest value chains, and consumer behavior and diets.

Over the past decades, smallholder sectors in developing countries have experienced extensive land use changes, resulting in deforestation and environmental degradation, while drivers of agricultural expansion vary significantly by local/country/regional contexts. Agroforestry has the potential to promote sustainable agricultural intensification and landscape restoration. Due to the significant heterogeneity in the smallholder systems in developing countries in terms of agro-ecological contexts and institutional/political settings, there are no silver-bullet agroforestry interventions in any situation. Understanding what drives deforestation and/or why and how farmers decide to adopt agroforestry technologies can be useful to guide tailoring technology packages to locally specific contexts. The International Centre for Research in Agroforestry (ICRAF), with World Agroforestry as a brand name, has led system research to enhance the contribution of agroforestry in transforming livelihoods and landscapes, and Japanese scientists have played a role. This paper provides an overview of the evolution of ICRAF’s research priorities over 40 years with special reference to the contribution of Japanese scientists. It discusses their significance in academic and policy contributions, understanding the causes of deforestation and its effects on people in Southeast Asia, and unpacking farmers’ decision-making processes in the adoption of agroforestry technologies in East Africa. The paper concludes with arguments on the way forward for agroforestry research.