Project Number: 1275-21220-223-02
Project Type: Specific Cooperative Agreement

Start Date: Sep 06, 2007
End Date: Jul 31, 2010

Objective:
Characterize isolates of P.erythroseptica found in the Northeast. Evaluate methods for best identifying cultivars with pink rot resistance. Evaluate chemical products for controlling pink rot.

Approach:
Tubers showing pink rot symptoms will be collected from growers in NY, PA, and neighboring States to allow the pathogen to be isolated and characterized. The field studies will be conducted on the farm of John Johnson in Athens, PA. Greenhouse plant inoculations and tuber inoculations will be performed at Cornell to establish if these methods reflect field observation. Greenhouse and tuber screening are slow, and labor intensive, hence an in vitro plantlet screening method will be evaluated. We will alert the Co-operative extension agents in NY, PA, DE, VE, and ME of our interest in obtaining tubers infected with pink rot. The isolates from tubers from the various geographic locations will be established in culture. Genomic DNA will be isolated from the cultures and RAPD analysis performed to establish if the isolates are metalaxyl sensitive or resistant. Sixteen cultivars and fingerlings will be evaluated in a field with a history of pink rot. The cultivars evaluated in the field will be grown in the greenhouse (10 replicates, plants/cultivar/treatment) and the soil will be artificially inoculated with pink rot or sterile water. The number of infected tubers/plant/treatment and the severity of infection will be recorded at harvest.