Dec 28, 2010

OSU helps decode strawberry genome in bid to improve fruit

Researchers at Oregon State University have helped sequence the genome of a wild strawberry, laying the groundwork for genetic improvements to related fruits like apples, peaches and pears.

The advance was published online by the journal Nature Genetics.

"This will accelerate research that will lead to improved crops, particularly commercial strawberries," said OSU plant molecular biologist Todd Mockler, one of the lead researchers. "It could lead to fruit that resists pests, smells better, tolerates heat, requires less fertilizer, has a longer shelf life, tastes better or has an improved appearance."

An international team of more than 70 researchers, 13 of whom are at OSU, identified 34,809 genes on the seven chromosomes in the woodland strawberry known as Fragaria vesca.

They chose the diminutive perennial because it’s commonly used in research, is easy to breed, grows quickly and has a small genome. Additionally, it shares a substantial number of genes with apples, peaches, cherries, plums, and commercially cultivated strawberries – a crop that generated $12.9 million in gross sales for Oregon’s farmers in 2009, according to a report by the OSU Extension Service.

As part of their findings, the scientists identified genes that they think might be responsible for some of the berry’s characteristics like flavor, aroma, nutritional value, flowering time and response to disease. Knowing what individual genes do will allow researchers to breed crops for those specific traits. And in the case of tree fruits, they won’t have to wait years to see if those traits actually show up in the fruit. For example, with molecular breeding they would be able to cross a high-yielding pear tree with one that resists a certain fungal disease, and they’d be certain that the desired genes are actually present.

In addition to Mockler, the OSU part of the research was led by Pankaj Jaiswal, Aaron Liston, Sushma Naithani and Nahla Bassil, a plant geneticist with the U.S. Department of Agriculture who holds a courtesy appointment at OSU. Jaiswal’s lab assigned functions to about two-thirds of the strawberry’s genes. Liston compared the chromosomal locations of 389 genes that the strawberry shares with peaches and found support for the hypothesis that the rose family originally had nine chromosomes. Naithani’s lab predicted biochemical functions for various genes, and Liston and Bassil helped assemble the genome for the strawberry’s chloroplasts, an organelle that makes sugar and starches through photosynthesis.