THE SECRETS of the potato have been revealed as scientists release a genetic analysis of the humble spud. The study should help efforts to breed better disease resistance into this important international food crop.
Teagasc was the Irish partner in a Dutch-led “potato genome sequencing consortium”. The analysis, which began in 2006, involved 29 research groups in 14 countries studying the world’s most important non-grain food crop.
The genetic study has helped explain why it is so difficult to breed attributes such as disease resistance, yield and nutritional value into the potato. Details were released yesterday in the journal Nature.
The work shows the potato has more than 39,000 genes, at least 10,000 more than a human. It also reveals that once it was carried from its ancestral home in South America, it suffered from “acute inbreeding depression”.
This left it “susceptible to many devastating pests and pathogens, as exemplified by the Irish potato famine”.
Having the tuber’s genetic blueprint available should help change this. “The potato genome sequence provides a platform for genetic improvement of this vital crop,” the authors say.
“The biological insights afforded by the genome sequence are fascinating, but Teagasc’s main interest in participating in the project was to utilise the data to breed better potato varieties,” said Dr Dan Milbourne of Teagasc’s crops environment and land use research programme at Oak Park, Co Carlow.
Teagasc researchers had been breeding potatoes for more than 40 years, work that had led to popular varieties such as Rooster and Cara, said potato breeder Dr Denis Griffin. It currently takes 10 to 12 years to breed successful new varieties, but having the genetic sequence could reduce this significantly.
Teagasc breeders were already making use of the research findings in their efforts to boost disease resistance, Dr Milbourne added. “This will increase our ability to breed highly disease- resistant potato varieties. Later we should be able to expand this to more genetically complex characteristics such as cooking quality and nutrient uptake by the plant to reduce fertiliser use, which can be very difficult to breed for.”
The potato is central to global food security given it is the world’s third most important food crop. World production in 2009 reached 330 million tonnes, according to figures from the Food and Agriculture Organisation of the United Nations.
