New varieties of direct seeded rice for farmers in Lower Middle Income Countries

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Rice is the most important staple crop for people in low and lower-middle-income countries. It has been estimated that over 3.5 billion people in Asia rely on rice to live. Rice is the fastest growing food staple in sub-Saharan Africa, and one of the fastest in Latin America. Rice is a major user of water; approximately 24-30% of total fresh water and around 34-43% of total irrigation water is used in rice cultivation. The Intergovernmental Panel on Climate Change estimates that about 1.2 billion people could face freshwater shortages by 2020 and crop yields could drop by 30% by 2050. Water requirement for rice is two-three times that of other cereals. In the majority of the rice growing areas especially in lower and middle-income countries, it is cultivated in puddled transplanted conditions which is highly labour and water intensive. The requirement of large amounts of increasingly scarce water, labour and energy resources is making rice production less profitable. In addition, increased urbanisation has shifted labour from rural to urban areas. In many parts of South and Southeast Asia, farmers are switching to direct seeded rice (DSR) as a more sustainable alternative. To obtain a good crop using DSR it is imperative that the seeds germinate quickly in the soil and that the seedlings grow vigorously. However, because breeders have focused on developing traditionally cultivated varieties for puddled transplanted rice, there has been little or no selection for seed vigour and associated seedling traits desirable for DSR. The lack of stable yielding and dry direct seeded adapted varieties for DSR system is a major limitation in achieving the maximum yield potential under water and resource limited conditions. This project team has been successful in identifying rice lines suitable for DSR through their recent research. Using a parallel laboratory and field phenotyping programme on a large set of rice varieties, we have identified hitherto 'unknown' varieties more suitable to DSR in terms of their seed traits. As a next step, we want to use these lines to combine with current good yielding and disease resistant rice cultivars to generate new high-yielding "DSR adapted" rice varieties. Once we develop these new varieties, we would then evaluate their performance in the field at multiple locations. Finally, the most promising breeding lines will be nominated for state level and national level field trails before release of these varieties to farmers. This last step is beyond the timeline of this project; however, we have a clear vision for delivery in accordance with our partners. IRRI has a long track record in rice breeding, our partner having developed more than 50 new varieties over the last 20 years. With the changing climatic conditions and reducing labour-water availability, the potential contribution of "DSR adapted" rice varieties and DSR adapted cultivation system to develop a sustainable rice based agri-food system has never been more vital.