Potato and Sweetpotato Breeding and Genetics Programs

Department of Horticultural Science
Project Leader: Dr. G Craig Yencho
Researcher and Extension Associate: Mark Clough

This project is an on going effort to develop improved germplasm that expresses natural resistance to the Colorado Potato Beetle (CPB), one of the most significant insect pests of potato. Previous studies (Sinden et al. 1986 and others) have shown that a few accessions of the wild diploid potato species, Solanum chacoense, possess a a rare class of glycoalkaloids, leptines I and II, that are potent CPB feeding inhibitors. A unique feature of the leptines is that they are expressed only in the foliage, not the tubers. This is beneficial from a breeding perspective because glycoalkaloids at elevated levels in tubers are toxic to humans and livestock. We are currently working with a population of potatoes derived from a cross between S. tuberosum (4x) and a tetraploid S. chacoense (4x) developed by Dr. Lind Sanford, USDA/ARS Potato Geneticist. Our goal is to develop improved germplasm and/or cultivars that express high levels of resistance to CPB and we are using a combination of conventional and marker-assisted breeding techniques to facilitate this work.