Location: Vegetable Crops Research Unit
Title: Breeding for resistance to early blight in potato (Solanum tuberosum L.) Authors
Submitted to: American Phytopathological Society
Publication Type: Abstract Only
Publication Acceptance Date: May 12, 2014
Publication Date: N/A
Technical Abstract: Early blight of potato (Solanum tuberosum L.), caused by Alternaria solani, is a major cause of economic losses in many potato growing regions. We have identified two early blight resistant clones EB24-24 and EB24-3, which are hybrids between the cultivated (S. tuberosum) potato clone US-W4 (2x=24) and the wild diploid clone S. raphanifolium. These two early blight resistant clones have been crossed as a female to the diploid inbred line M6, which is homozygous for the Sli, which overcomes self-incompatibility in diploid potatoes. Twenty-three plants of EB24-24×M6 and three plants of EB24-3×M6 were spray inoculated with a sporangial suspension of A. solani strain 208m2 at a concentration of 20,000 sporangia/ml. Seventeen BE24-24×M6 plants and one EB24-3×M6 plant were retained because they were resistant and produced seeds following self-pollination. A second EB resistance screen was carried out on the EB24-24xM6 family using drop inoculation on a detached leaf and spray inoculation of whole plants with sporangial suspensions of A. solani (20,000 sporangia/ml). One F1 clone from each family was selected and the F2 generation was planted for both families. These families are being evaluated for seed germination, seedling vigor, fertility, self-compatibility, and early blight resistance. The population with the best segregation for early blight resistance will be genotyped using the SolCAP Illumina 8303 array. Our goal is to identify molecular markers associated with early blight resistance for use in marker-assisted selection.