Upland Rice - Fighting The Blast Fungus

Fighting The Blast Fungus

Recently, scientists have been improving their knowledge of the genetics of resistance to the Blast fungus, one of the most damaging diseases of rice, and are using the techniques of biotechnology to develop cultivars with more durable disease resistance.

In the uplands, blast is particularly important because the environment favors its proliferation. Although many traditional upland cultivars show stable resistance to this disease under low-input cropping practices, they have other characteristics that make them difficult to use in intensified systems. So the risk from blast increases as cropping practices intensify and improved varieties are introduced.

IRRI scientists have been working with colleagues in the Upland Rice Research Consortium to better understand pathogen populations and to identify resistance genes found in some cultivars. Armed with this knowledge, they are working with IRRI's upland rice breeder to combine such genes with other desirable traits for incorporation into new upland varieties.

Consortium scientists are also trying to understand how upland rice farmers' cropping systems contribute to soil erosion, with the aim of proposing possible erosion control techniques. Studies in the Philippines have shown, for example, that hedgerows of trees, shrubs and grasses along hill contours can help reduce soil erosion up to 90 percent. Rice or other crops are planted between these strips of permanent ground cover.

Leguminous plants in hedgerows make substantial amounts of atmospheric nitrogen available to both riceplants and annual crops and recycle other nutrients and organic matter.

Such legumes can simultaneously increase farmers' incomes and contribute to sustainability of the farming system.