OREGON STATE UNIVERSITY

Potato clones resist "Virus Y"

07/18/1997

POWELL BUTTE, Ore. - Genetically altered clones of popular potato varieties could be just the ticket for potato producers looking for built-in resistance to potato virus Y, an aphid-spread disease notorious for taking a huge toll on potato yields.

Tests at Oregon State University branch experiment stations show the clones, which could be released for grower use in five years, can save up to 40 percent of yields lost to virus disease.

"Even though our tests show the clones yield about 10 percent less than standard varieties, that's a lot better than a 40 percent loss," said Steve James, research agronomist at the Central Oregon Research Center, headquartered at Madras, who is coordinating the virus project. "Currently, growers spend $100 to $200 per acre on insecticides to control the aphids. Growing PVY (potato virus Y)-resistant clones would reduce pesticide applications and put that money in growers' pockets."

At the central Oregon center's Powell Butte branch, James receives clones developed by former OSU microbiology researcher Bill Dougherty. James increases seed for research trials and screens the potatoes for agronomic characteristics. "We want clones with good yield, tuber size and tuber quality, in addition to having resistance to PVY," James said.

Research trials on clone yields, quality and virus resistance are also being run by OSU researchers Dan Hane, an agronomist at OSU's Hermiston Research and Extension Center, and Ken Rykbost, superintendent of OSU's Klamath Experiment Station. Under test are genetically altered versions of Russet Burbank, Russet Norkotah and Shepody potato varieties.

Eleven genetically altered Narkotahs, two Shepodies and 10 Russet Burbanks have been put through tests at the three OSU branch experiment stations and at a University of California facility at Tulelake, Calif. In 1996 trials, virus-infected potatoes yielded 40 percent less than virus-free potatoes in plots at Hermiston, 20 percent less at Tulelake and seven percent less at Klamath Falls.

Rykbost said several clones look promising for release as commercial varieties, but they must go through formal testing in a western regional evaluation program involving Oregon, Idaho, Washington, California, Colorado, Texas and New Mexico. Each potential variety is tested in all seven states by land grant universities and the USDA, he added.

"If our tests show we have potatoes with PVY resistance and yields even close to those of standard varieties now available, we should have something really worthwhile for commercial production."