Researchers from Michigan State University describegenetic toolsto
develop potato varieties with improved resistance to the devastating
Colorado potato beetle.

The research team explored the wild relatives of domesticated potatoes
for their natural defenses against these beetles as these wild plants
make their own beetle-killing compounds. They compared the chemical
profiles of hundreds of individual potatoes with their resistance to the
Colorado potato beetle in the field and found chemical signatures that
could predict resistance.

To go around the complication of potatoes having four copies of
eachgene, the team led by Natalie Kaiser used diploid potato varieties,
those that naturally only have two copies of each gene. But many diploid
potato varieties are self-incompatible, so Kaiser and her team developed
diploid potatoes that are self-compatible. Through this process, Kaiser
and her team discovered that multiple genes and the environment
determine whether some potatoes can produce self-fruit and seed.

The new potato varieties and genetic tools will allow researchers to
"examine the genetic foundations of self-fertility, and insect and
disease resistance," says Kaiser. "This way, we can create new potato
varieties that were previously infeasible," she added.

Breeding beetle-resistant potatoes | American Society of Agronomy
[www.agronomy.org]