Impacts of rice diseases in tropical Asia

Asia is home to 800 million of the world’s 1.1 billion poor and accounts for 90% of global rice consumption. Only 7% of the annual global rice production is traded internationally by a few exporting countries. Local variation in production may then have large impacts on trade and price. Reduction and variation in rice production is partly attributed to yield losses caused by diseases and pests. However, there have been limited efforts prior to the late 1980s to systematically quantify the impact of rice diseases and pests compared with other cereals. Several reports based on farmers’ field surveys and experiments conducted since 1987 have documented the importance of diseases, insect pests, and weeds of lowland rice in Asia, the linkages between production situations and injury profiles, and the potential of improved crop health management to sustainably generate yield gains. Recent surveys of farmers’ fields conducted in tropical Asia showed increasing adoption of specific cropping practices and the emergence of new production situations. These production situations resulted in the emergence of new diseases and disease profiles, along with new crop loss patterns. Results highlight the need to consider the variation and dynamics in production situations to understand the impact of diseases and develop pest management strategies in tropical Asia