Maize genome offers hope of improved varieties

Scientists have sequenced the genome of maize, providing data for plant breeders around the world aiming to improve maize varieties in the face of hunger and climate change.

Published today (20 November) in Science, the research will not only have far-reaching effects on the development of new maize and other cereal crops but also represents a major scientific accomplishment, say researchers.

The genome sequence of a variety of maize called B73 was deciphered by more than 150 scientists under lead researcher Patrick Schnable, based at Iowa State University in the United States. They identified more than 32,000 genes.

The research is "a milestone in genetics and plant biology", wrote Catherine Feuillet, a senior scientist at the cereals unit of Frances National Institute of Agronomic Research, in an accompanying perspective article.

Sequencing maize was a challenge because of its huge size — almost as large as the human genome — and complex organisation, in which the genes are often found in islands within swathes of DNA that is not directly encoded into protein.

The researchers said the sequence will "facilitate efforts to meet the worlds growing needs for food, feed and energy ... in an era of global climate change".

It also paves the way for the sequencing of crops such as wheat and barley, "whose larger and more complex genomes have long been viewed as making these plants unapproachable", wrote Feuillet.

The sequence has already been put to use. Science published three papers alongside the sequence, one of which compares specific sections of the genome of 27 globally representative maize varieties to show common patterns of genetic variation.

The research, led by Michael Gore of the Institute for Genomic Diversity at US-based Cornell University, is expected to be useful in teasing out the genetic basis for important traits, such as yield, quality and stress tolerance. This will allow scientists to develop improved crops with better yields and higher nutritional content.

"Already a critical source of food, fuel, and fibre, the addition of genomic information allows maize to be further improved through plant breeding that exploits its tremendous genetic diversity," the team wrote.