ARS | Publication request: Tuber Dormancy Lasting Eight Years in the Wild Potato Solanum Jamesii

Submitted to: American Journal of Potato Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 3, 2009
Publication Date: April 1, 2010
Citation: Bamberg, J.B. 2010. Tuber Dormancy Lasting Eight Years in the Wild Potato Solanum Jamesii. American Journal of Potato Research. 87(2):226-228.

Interpretive Summary: Potato growers and consumers would benefit from better control of tuber dormancy (seed potatoes sprouting just when desired, and the harvested crop not sprouting at all). Control of dormancy could also prove useful for preservation of genetic stocks in potato genebanks. Most potato tubers remain firm, healthy and unsprouted for less than a year, even in refrigeration. But we found that the wild potato species Solanum jamesii collected from the southwest USA had tubers that remained in viable condition much longer. For the best population, one-third of the tubers were unshriveled, and over 90% of those sprouted and produced normal plants after eight years in refrigeration. Discovery of this extreme dormancy should open opportunities for research to better understand the underlying physiology and genetics, and thereby find techniques to more effectively manipulate dormancy in the potato crop.

Technical Abstract: Control of tuber dormancy is of interest for commercial potato production and for germplasm preservation in the genebank. Solanum jamesii plants were collected by the author from the wild in New Mexico and Arizona, USA in 1998 and grown in the greenhouse. Tubers harvested in 1999 were placed in paper bags in a continuous 40F (5C) tuber storage cooler. No sprouting was observed through fall of 2007 but some tubers had shriveled. Firm tubers were moved to room temperature and planted in the greenhouse in January 2008. After three months, an average of nearly 50% of tubers had sprounted and produced normal plants. This extreme eight year tuber dormancy in S. jamesii should be a valuable research tool for study of dormancy physiology in potato.