|Bae, Jin Joo - UNIV OF WISC, MADISON|
|Rouse, Doug - UNIV OF WISC, MADISON|
Submitted to: American Journal of Potato Research
Publication Type: Abstract Only
Publication Acceptance Date: January 15, 2007
Publication Date: February 15, 2007
Citation: Bae, J., Jansky, S.H., Rouse, D. 2007. Early generation selection for resistance to verticillium wilt [abstract]. American Journal of Potato Research. 84(1):75. Technical Abstract: Verticillium wilt (VW) of potato, caused primarily by the fungus Verticillium dahliae, is an important soil-borne disease that causes yield loss. Resistance to VW exists in potato germplasm and is used by breeders during cultivar development. Breeders could make more rapid progress toward the development of VW resistant clones if they had an effective early generation selection strategy. The purpose of this study was to determine whether selection for VW resistance could be carried out in the first tuber generation on single hills. One hundred fifty two clones from 19 families were planted as single hills on a V. dahliae-infested field. Each plant was scored for vine maturity, VW symptom expression, yield and stem colonization (colony forming units (cfu) in dried basal stem segments). Clones were tentatively classified as resistant or susceptible based on symptom expression, yield, or both. The efficiency and reliability of this selection strategy was determined by comparing single hill data to stem colonization scores in the second clonal generation, which consisted of replicated four-hill plots. The best selection efficiency resulted from selection against more than 20% of symptom expression in early August and less than 2 lb. of yield at harvest. With this selection strategy, 30% of the clones were discarded; 80% of the clones that were retained were resistant to VW. When selection was based on symptom expression, decisions made earlier in the growing season were more effective than those made later in the season.