Project Number: 1245-21220-251-02
Project Type: Specific Cooperative Agreement

Start Date: Jul 21, 2009
End Date: Sep 30, 2013

Objective:
1. Evaluate potential biologically active control measures in controlled conditions and the field. 2. Monitor the location-specific variation in scab resistance of potato breeding material and newly released cultivars by field testing (national trials).

Approach:
Potato seed pieces of 3 popular but scab-susceptible varieties (Yukon Gold, Ranger Russet and Atlantic) will be treated with several individual non-pathogenic isolates of Streptomyces, and planted in Pennsylvania and Michigan fields with high common scab pressure. Treatments will be planted in 4 replicates in a randomized block design, and evaluated at harvest for incidence and severity of common scab. Field test varieties for scab resistance in multiple locations. A total of 20 newly-released potato cultivars and advanced breeding selections plus four popular cultivars as checks (Atlantic, Ranger Russet, Russet Burbank and Superior) will be tested in common scab nurseries in 4 locations, embodying a range of environmental conditions and different pathogen populations. Locations are in Aberdeen, ID, Becker, MN, E. Lansing, MI and University Park, PA. A randomized complete block with three replications of 4 hills will be planted for each clone. At harvest, each tuber will be rated for percent surface area covered with lesions and type of lesion. Data from cooperating sites will be analyzed. The resulting comparison and ranking of susceptibility to predominant Streptomyces isolates will be made available to growers to help them select the most scab-resistant cultivars for their region.