More than half of the world’s potentially arable lands consist of acid soils, where aluminium (Al) toxicity is the primary factor limiting maize yield, one of the world’s most important food crops. This problem is particularly acute in low-input agricultural systems, which encompasses a large portion of the farmers in sub-Saharan Africa, as well as smallscale farmers in other developing regions.

Maize is the most important cereal in sub-Saharan Africa. Aluminum toxicity comes close to rivaling drought as a food-security threat in critical tropical food-producing regions.

In combing the maize genome for clues as to why some plants can tolerate toxic aluminium in soil, USA scientists found three copies of the same gene known to affect aluminum tolerance, according to new research jointly led by the United States Department of Agriculture (USDA) and Cornell Unversity. 

“We found three functional copies that were identical,” reveals Dr Leon Kochian, Director, USDA's Agriculture Research Service Plant, Soil and Nutrition Laboratory at Cornell, talking to Newswise. “This is one of the first examples of copy number variation contributing to an agronomically important trait.” Dr Kochian also doubles as the Product Delivery Coordinator for our Comparative Genomics in Cereals Research Initiative.

The research was funded by GCP, with Dr Kochian as the Principal Investigator.

Findings were published earlier this month in USA's Proceedings of the National Academy of Sciences (PNAS), in a paper enttitled Aluminium tolerance in maize is associated with higher MATE1 gene copy number, of which Dr Guimãraes is the second author. Abstract. 

Links

• Newswise: In triplicate, genes make maize tolerant to toxic soil
• Project on alumunium tolerance in mazie and sorghum
• GCP's Comparatve Genomics in Cereals Research Initiative
• Leon Kochian's profile