First Strawberry Genome Sequence Promises Better Berries

Tom Davis, professor of biological sciences at UNH, and postdoctoral researcher Bo Liu were significant contributors to the genome sequence of the woodland strawberry, which was published last month in the journal Nature Genetics.

“We now have a resource for everybody who’s interested in strawberry genetics. We can answer questions that before would have been impossible to address,” says Davis, who has been working on the strawberry genome project since 2006 as part of the international Strawberry Genome Sequencing Consortium.

For instance, says Davis, breeders can now look at the DNA “fingerprint” of strawberry plants to more easily breed those with enhanced flavor, aroma, or antioxidant properties. Or they could breed more disease-resistant berries, decreasing the significant amount of spraying that cultivated strawberries currently need to thrive and thus enhancing the berry’s healthful qualities.

Further, the woodland strawberry is a member of the Rosaceae family, which includes apples, peaches, cherries, raspberries, and almonds, all economically important and popular crops; researchers say the DNA sequence of the strawberry genome will inform the breeding of these other fruits. “We can now begin to understand how evolution works at the level of the genome on this family of plants we all enjoy,” says Davis.

The genome sequencing effort, led by researchers at the University of Florida and Virginia Tech, found that the woodland strawberry — Fragaria vesca – has240 million base pairs of DNA (compared to 3 billion for humans), making it one of the smallest genomes of economically significant plants. The consortium focused first on sequencing the wild woodland strawberry because its cultivated cousins, all hybrids, are far more complex.

Building upon prior publications in which he described a one percent genomic sampling of a native New Hampshire wild strawberry, Davis played multiple roles in genome project planning, data interpretation, and manuscript preparation. Liu’s unique contribution to this effort was to independently document the locations of specific sequences called ribosomal gene clusters on the chromosomes themselves, using an advanced microscopic technique known as fluorescent in situ hybridization.

The Nature Genetics paper, “The genome of the woodland strawberry,” is available here: http://strawberrygenes.unh.edu/Published.740%5B1%5D.pdf. By fortuitous coincidence, the complete genomic sequence of another delectable plant species, Theobroma cacao (chocolate), was published in the same journal issue. More information on strawberry genome work at UNH is at strawberrygenes.unh.edu. The UNH component of this work was supported, in part, by the New Hampshire Agricultural Experiment Station and by a grant from the U.S. Department of Agriculture (National Research Initiative) Plant Genome program.

The University of New Hampshire, founded in 1866, is a world-class public research university with the feel of a New England liberal arts college. A land, sea, and space-grant university, UNH is the state's flagship public institution, enrolling 12,200 undergraduate and 2,300 graduate students.