Herbicide tolerance in diploid 1EBN and 2EBN potato species

Bradeen, J. M. and D. S. Mollov

University of Minnesota, Department of Plant Pathology, 495 Borlaug Hall, 1991 Upper Buford Circle, St. Paul, MN 55108

Wild potato species are rich sources of genes for improvement of cultivated potato. Superseries Stellata encompasses diploid 1EBN and 2EBN species grouped into nine series. These species are documented sources of resistance to biotic and abiotic stresses. Identification and characterization of useful genes in these species often requires field evaluations, yet little has been reported on the cultivation of these materials. In this two year study, tolerance of seedlings of ten diploid potato species to two commonly used broadleaf herbicides, linuron and metribuzin, is evaluated. Each species is represented by four populations and a total of five herbicide treatments are employed. Comparison of visual ratings and aboveground biomass fresh weights revealed variable responses to herbicide treatments. On average, metribuzin treatment reduced biomass accumulation and seedling survival more than did linuron treatment. Only Solanum pinnatisectum was tolerant of both linuron and metribuzin. Solanum cardiophyllum, S. jamesii, and S. trifidum may be segregating for tolerance to linuron. Species grouped into a common series based on morphological and molecular data do not necessarily respond to herbicide treatment in the same manner. The results of this experiment may assist researchers in establishing field cultivation methods for seedlings of wild potato species.