Colorado potato beetle (Coleoptera: Chrysomelidae): expression of resistance in Solanum berthaultii and interspecific potato hybrids

A wild potato species, S. berthaultii Hawkes, and its interspecific hybrids with the commercial potato, S. tuberosum L., were evaluated for resistance to the Colordao potato beetle (CPB), Leptinotarsa decemlineata (Say) in field and laboratory studies in New York. Field-collected summer adults produced nearly 3-fold more eggs on S. tuberosum cv. Katahdin than on S. berthaultii over a 7-day period. Egg masses laid on "Katahdin" were 61% larger than those laid on S. berthaultii . In field cage plots of S. berhaultii , CPB larval development was retarded and vary few larvae survived to adulthood. Densities of overwintered CPB adults and defoliation levels were significantly reduced on S. berthaultii . A hybrid family had intermediated levels of defoliation and adult CPB densities. During the second CPB larval larvae were reduced 90 and 87%, respectively, on the hybrid family and 96 and 97%, respectively, on S. berthaultii compared with CPB densities on S. tuberosum .