Product Line 3.1. Future management systems for efficient rice monoculture
Double- and triple-crop rice monoculture systems occupy a land area of 24 million hectares in tropical and humid subtropical Asia, accounting for 40% of global rice production. In Southeast and East Asia, double cropping of rice occurs on large inland plains and in major river deltas where irrigation allows for rice cropping in the dry season (e.g., the “rice bowls” in deltas of the Mekong, Red, Ayeyarwady, Ganges-Brahmaputra, Cauvery, Yangtze, and Chao Phraya rivers). Intensification of lowland cropping systems in Asia since the mid-1960s has increased the number of crops grown per year and the yield per crop cycle. Triple cropping of rice occurs in the Mekong Delta of Vietnam and in parts of other countries. It is increasingly proposed as a response to reduced food security by several nations (e.g., Indonesia, Philippines). These intensive rice production systems are the main economic activity in many rural areas, they provide the staple food for hundreds of millions of people, and they greatly affect the livelihoods and health of the urban and rural poor.
To be sustainable, however, such intensive rice monocropping systems must be managed well. Overuse and losses of agro-chemicals (pesticides, fertilizers) may pollute the environment and diminish the capacity to deliver of other ecosystem services, while consumption of limited resources (e.g., water, phosphorus) depletes precious natural resources. Farmers urgently need new water management options to alleviate increasing water scarcity. Ecological resilience of monocropped rice ecosystems and their capacity for natural control of rice pests are weakened by overuse of pesticides and the breakdown of rice host-plant resistance. Animal pests (insects, rodents, nematodes, birds), diseases, and weeds are responsible for a combined loss of rice production of 25–45% in tropical and subtropical Asia. Recently, acute outbreaks of planthoppers and rodents have occurred in intensive monocropped rice areas in Asia. Planthoppers damage rice crops directly, and indirectly by transmitting devastating virus diseases. The spread of new viral diseases is being observed alongside planthopper outbreaks in East and Southeast Asia. Water scarcity leads to less flooding of rice fields, which induces weed species shifts and enhances weed growth. Weed resistance to several herbicides is already confirmed in several countries. In the end, component technologies such as water, nutrient, pest, and disease management need to be integrated as they often interact; thus, holistic approaches are needed.
In Africa, fully or partially irrigated rice is grown on about 1.7 million ha in countries such as Egypt, Mali, Senegal, Côte d’Ivoire, Guinea, Madagascar, Nigeria, and Tanzania. About 1 million ha of that are under intensive management. With an average yield of 10 t/ha, productivity in Egypt can be considered the highest in the world. Enhanced rice production in Africa will depend to a large extent on enhancing cropping intensity in irrigated systems as well as expanding irrigation areas. A major issue for the near future will be to introduce water-saving measures in such systems, in farmers’ fields as well as in delivery systems, to maintain the natural resource base and enhance rice production. In Latin America, irrigated rice accounts for nearly 60% of rice production, with the largest irrigated rice systems found on 1.3 million ha in the Southern Cone region (southern Brazil, Uruguay, Argentina).
This product line includes management technologies and their underpinning science to enhance the profitability and productivity of rice monocropping systems while at the same time reducing negative externalities. It delivers integrated management options and their underpinning science to improve water-use and nutrient-use efficiencies, and protect rice from animal pests, diseases, and weeds. Potential impact is improved food security, enhanced livelihoods, and a clean environment, which are derived from profitable, sustainable, environment-friendly, and resilient rice cropping systems that are ready for the future. The key research question is how the profitability and productivity of rice-based cropping systems can be increased while simultaneously reducing negative externalities.
Activities combine long-term and on-station field experimentation at so-called “experimental platforms” with adaptive and participatory crop, water, crop health, and soil management research. At the experimental platforms, cropping systems “of the future” that respond to major drivers of change are designed and tested. Detailed process-based science is developed to support the optimization of these cropping systems. Adaptive research trials will be established in farmers’ fields with our research and extension partners, and will deliver concrete site-specific management recommendations for rapid out-scaling. Site-specific nutrient management and water-saving technologies will be developed. Pest and disease management guidelines will be integrated with water, nutrient, and crop management practices to arrive at best-bet integrated management recommendations. Innovation partnerships and learning alliances will ensure that indigenous and local knowledge are captured and that gender-specific issues are examined in the design of new management technologies.
3.1.1 Strategies to improve water-use efficiency
3.1.2 Principles and tools for site-specific nutrient management
3.1.3 Management options for pests, weeds, and diseases
3.1.4 Integrated good agricultural practices (GAP)
Advanced research institutes and universities, especially those in BRIC countries, are partners in the research on and development of new technologies and the underlying science. For example, CAU, WU, and HZAU in China and IARI in India are long-standing partners in the development of water-saving technologies such as alternate wetting and drying and the aerobic rice production system. Local adaptive research and dissemination/diffusion involve an array of public- and private-sector partners. For example, adaptive research and development of site-specific implementation of water-saving technologies and aerobic rice in other target countries in Asia are done in collaboration with local and national R&D institutions such as PhilRice, CLSU, and BSWM in the Philippines; and DPP, CLRRI, NOMAFSI, and FCRI in Vietnam. Boundary partners for further uptake and widespread diffusion include formal public-sector extension agencies, NGOs (e.g., World Vision in Vietnam), civil society groups, farmer groups, irrigation system managers (for water-saving technologies), and the private sector such as fertilizer companies (for SSNM) and Syngenta (for AWD). For Africa, expertise from Asia will be mobilized and enhanced collaboration will be established with research institutes in Egypt.
Products feed into GRiSP theme 6 and other national and regional co-investment programs for accelerated and large-scale delivery. The IRRC is a major mechanism to link the development of management technologies with local partners for adaptive research and to accelerate diffusion through fostering and promoting innovation partnerships. It also plays a pivotal role in linking the development of the new products of this product line with large-scale diffusion efforts to support the growth of the rice sector (theme 6). Regional and global public goods are taken up and site-specifically adapted by local R&D partners whereas extension and boundary partners adapt and diffuse technologies to farmers and farmer groups. This PL will also closely collaborate with the CRP on land and water, in which field-/farm-level rice technologies are placed in a larger regional context. A concrete example of an impact pathway is given below for site-specific nutrient management.
The IRRC, several projects funded by ACIAR, ADB, and MAFF (Japan), private-sector grants, and new projects focusing on future systems (the Ecological Intensification project) are the current major funding mechanisms for this product line. Extra funds need to be raised to ramp up the development of tools to quantify the biophysical and economic footprints of rice production and to develop management technologies that will reduce these footprints. Substantial continued funding of 3.1.4 is of high priority. There is a need to invest in capacity development on ecological intensification concepts. Activities in Africa focusing on water savings will need to source additional funding.