Characterising genetic and soil induced variation in arsenic uptake, translocation and metabolism in rice to mitigate arsenic contamination in Asia

Lead Research Organisation: Rothamsted Research
Department Name: Unlisted

Abstract

Extensive regions of South East Asia suffer from elevated arsenic in paddy soils through irrigation with arsenic contaminated groundwaters and from base and precious metal mining activity. Anaerobically grown rice accumulates arsenic in grain much more effectively than aerobically grown grain crops, to such an extent that even at background levels rice contributes considerably to dietary exposure of this carcinogenic element. The overall objective of this project is to identify the genetic and environmental controls on arsenic translocation to grain so that rice can be bred for use on high arsenic soils. The specific objectives are:
1. To identify strategies for producing rice grain with low levels of arsenic with a high proportion of organic arsenic species.
2. To disseminate this information effectively, to enable cultivar selection and breeding programs to be highly focused, and so that the currently available most suitable cultivars identified are advertised and deployed in affected regions.
3. To provide training for SE Asian scientists in modern analytical and molecular techniques which can be applied to the arsenic and other grain crop problems.
4. To identify candidate genes for low arsenic uptake into the shoot, low rates of translocation from shoot to grain, and a high rate of transformation of inorganic arsenic to the less toxic organic species dimethyl arsenic acid (DMA).
5. To identify which locally selected cultivars are best to use on arsenic contaminated soils.
6. To map Quantitative Trait Loci (QTLs) for low straw and grain arsenic levels low ratio of inorganic to organic arsenic.
7. To understand how genetic variation in arsenic parameters interacts with the two arsenic pollution scenarios relevant to South East Asia, namely groundwater polluted paddies and mine waste contaminated paddies.
8. To elucidate the soil factors affecting arsenic bioavailability to rice.

Publications

10 25 50