|DOUCHES, DAVID - Michigan State University
Submitted to: American Journal of Potato Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/27/2017
Publication Date: 12/29/2017
Citation: Jansky, S.H., Douches, D., Haynes, K.G. 2017. Transmission of scab resistance to tetraploid potato via unilateral sexual polyploidization. American Journal of Potato Research. 95(3):272-277. https://doi.org/10.1007/s12230-017-9628-7.
Interpretive Summary: Common scab of potato is caused by a soil-borne bacterial pathogen. The disease results in losses of marketable yields, as tubers with scab lesions are discarded during grading. Common scab cannot be controlled effectively with cultural practices, so host plant resistance is the best option for disease control. In this paper, we describe the transfer of resistance from exotic potato germplasm into clones that can be used as parents in breeding programs. This germplasm has the potential to contribute to improved resistance to common scab in new potato cultivars.
Technical Abstract: Resistance to common scab continues to be a high priority trait for potato breeders. We have identified a source of resistance in the diploid wild potato relative Solanum chacoense and have introgressed it into cultivated potato by crossing it to a dihaploid. A clone generated by crossing two full-sib hybrids is highly resistant and produces both 2n pollen and 2n eggs. This clone, named 4-48, is homozygous for a major QTL for scab resistance derived from S. chacoense. Clone 4-48 was reciprocally crossed to the cultivars Megachip, Pike, and White Pearl. Resistance was transferred to tetraploid offspring, with transmission through the male parent generally more effective than through the female parent. The majority of progeny exhibited stability for resistance to common scab across environments. This germplasm will be useful for breeding new resistant cultivars.