Weed Tolerant and Environment-friendly Sorghum

Sorghum produces a natural defense chemical that prevents growth of weeds in its immediate vicinity. The compound sorgoleone is produced in the plant root hairs and when overly generated results to soil toxicity, making multiple cropping with sorghum impossible.

A group of research scientists at the ARS Natural Products Utilization Unit in Oxford, led by Stephen O. Duke found that a special type of enzyme is responsible for the production of sorgoleone. The team found the gene sequences associated with that class of enzymes through sequence tagging in the sorghum genomic database. Experiments conducted to determine the gene function through gene silencing revealed reduction in sorgoleone emitted by the sorghum plants produced.

Further studies will lead to the development of sorghum lines which does not cause soil toxicity problem and environmental hazards, but could still ward off weeds. Similar studies are also being conducted in other crops, and recent findings show that rice contains similar sequences involved in the production of defense-related enzymes.

For details, see the news article at  http://www.ars.usda.gov/is/pr/2010/100615.htm