OSU releases new hazelnut variety resistant to filbert blight

April 22, 2005

OSU's Santiam hazelnuts

Unblanched and blanched kernels of OSU's newest hazelnut variety, Santiam. The trees are completely resistant to eastern filbert blight. Photo: Becky McCluskey, Dept. of Horticulture

CORVALLIS – The new hazelnut variety, 'Santiam', just released by the Oregon State University Agricultural Experiment Station, offers Oregon hazelnut growers an effective tool in their fight against the destructive plant disease eastern filbert blight, which has infected many of the state's hazelnut orchards.

Santiam is the first main hazelnut crop variety developed by OSU's long-running hazelnut breeding program to have complete resistance to eastern filbert blight, according to Shawn Mehlenbacher, OSU Agricultural Experiment Station researcher and hazelnut breeding program leader. Santiam also is an early-maturing hazelnut variety with high-yield efficiency, he said.

Oregon is the top hazelnut producer in the country, annually producing about 99 percent of the U.S. hazelnut crop. Last year's Oregon hazelnut harvest earned over $30 million in farm gate sales.

Eastern filbert blight is a fungal disease that kills trees via the growth of cankers that slowly girdle branches, limbs and tree trunks. This leads to die-off of leaf growth in the tree canopy and eventual death of the entire tree. Spores of the disease spread from tree to tree and orchard to orchard.

Willamette Valley hazelnut growers first noticed effects of the blight in 1986. They tried to control it by using fungicide sprays, pruning infected branches and planting blight-resistant hazelnut varieties.

Despite these efforts eastern filbert blight has continued to destroy hazelnut trees and the disease has been blamed for removal of several hundred acres of hazelnut orchards from production in recent years.

Developing a hazelnut variety with full resistance to the blight has been a top priority for the OSU Agricultural Experiment Station hazelnut breeding program over the past three decades.

“The introduction of Santiam is a major step in our efforts to support the state's hazelnut industry,” said Mehlenbacher. Breeding development work will continue on varieties that combine eastern filbert blight-resistance with improved hazelnut quality, he added.

Santiam has been released to the public with no restrictions. Hazelnut tree nurseries in the Willamette Valley now have the variety and are producing trees through micropropagation (tissue culture) and grafting.

Author: Bob Rost
Source: Shawn Mehlenbacher