Project Number: 500-42-001-59
Project Type: Grant

Start Date: Mar 31, 2004
End Date: Mar 30, 2005

Objective:
Evaluate advanced breeding lines from all US breeding programs for infection with a complex of P. infestans isolates of the US genotype; evaluate tuber resistance to P. infestans on germplasm with foliar resistance, and summarize the data and distribute report to the breeders.

Approach:
Advanced breeding lines and cultivars will be planted in a randomized complete block design with three replications in early June. Percent foliar infection will be visually assessed weekly following inoculation during August and early September. The evaluations will conclude when the susceptible lines reach 100% infection. To compare the reactions of the potato lines across years, the Relative Area Under the Disease Progress Curve (RAUDPC) will be calculated for each line. RAUDPC is the Area Under the Disease Progress Curve (AUDPC) divided by the maximum AUDPC (100 X the total number of days after inoculation). Analysis of variance will be performed on the RAUDPC values. The least significant differences (LSD) will be calculated using the SAS general linear models procedure. Surface sterilized tubers will be inoculated with a sub-peridermal injection of a zoosporangia suspension of different virulent biotypes of P. infestans. Ten control tubers will be inoculated with cold (4oC) sterile distilled H2O. After inoculation, tubers will be stored at 10C and samples taken for destructive sampling at 40 days after inoculation. Sample tubers will be sectioned transversely in a series from base of tuber to apical end. As infected potato tuber tissue darkens in response to late blight progress through the tuber, an image analysis-based rating of the tuber symptom levels will be made.

Project Team

Bennett, A. Rick David Douches - Professor 301-504-6915

Related National Programs

Plant Diseases (303)