NZ company contributes to strawberry research

Scientists from 38 organisations in ten countries, including New Zealand-based researchers at Plant & Food Research, have collaborated to publish the complete DNA sequence of the woodland strawberry.

The genetic secret of the wild strawberry has been unravelled by scientists including New Zealand-based researchers at Plant & Food Research.

Scientists from 38 organisations in ten countries collaborated to publish the complete DNA sequence of the woodland strawberry.

This genome sequence will be utilised by scientists in identifying genes and gene function in a number of fruit crops, ultimately speeding up the time to produce new varieties.

The strawberry has the smallest genome in the Rosaceae family, which includes other well known fruits such as apple, peach, and berries.

The Rosaceae family is vital for modern horticulture, producing highly valuable fruits such apple, peach, nectarine, almonds and berryfruits, says Dr Roger Hellens, science leader geonomics at Plant & Food Research.

"By having the sequence of the most genetically-basic of these plants, strawberry, we can search for genes controlling key commercial traits and identify them in related plants. This will ultimately speed up our search in the more complex Rosaceae genomes and allow us to reduce the time to breed fruit plants with characteristics most desired by the consumer," Dr Hellens said.

Due to its quick reproduction time and the small area needed to grow the plant, the strawberry is an ideal model plant for fruit gene studies.

Most of the genes in strawberry are present in other Rosaceae plants, although many are duplicated resulting in more complex genomes and plant structures, Dr Hellens added.

Using the strawberry genome to identify and understand genes that control key traits, such as colour and flavour, scientists can identify the matching gene in other fruit plants and screen breeding populations for individual plants with ideal characteristic combinations.

The woodland strawberry was the original strawberry cultivated in Europe in the 17th Century. It is cousin to a modern Christmas favourite, the garden strawberry, one of the youngest cultivated fruits originating around 250 years ago through modern plant breeding techniques.

The complete genome of the woodland strawberry, Fragaria vesca, is published in the prestigious journal Nature Genetics and includes only 206 million DNA base pairs, encoding close to 35,000 genes.

The apple genome, published in August 2010, is three times the size. The strawberry genome is the second smallest plant genome to be sequenced - the sequence for Arabidopsis, widely used as a model in plant studies, is about 125 million DNA base pairs and was first published in 2000.

The group working on the strawberry genes sequenced the wild plant's genome by breaking it up into millions of short segments which were sequenced individually and then reassembled.

Plants tend to have far more complex DNA than animals, and the scientists identified 34,809 genes in the wild strawberry. Humans have around 20,000 to 25,000 genes.

Scientists said in August they had decoded and published almost all of the highly complex genome of wheat, a staple food for more than a third of the world's people.

- NZPA