Colorado Potato Beetle Resistance in Somatic Hybrids of Diploid Interspecific Solanum Clones

Abstract

The Colorado potato beetle (CPB) is a major insect pest that is controlled mainly through the use of pesticides. Development of potato clones with multiple forms of host plant resistance may provide a stable alternative or supplemental form of CPB control. Tetraploid hybrids were developed by somatic fusion of diploid interspecific Solanum clones with different forms of resistance to CPB. Hybrids were created between a clone containing leptine glycoalkaloids and four clones producing glandular trichomes. One fusion produced vigorous hybrids that were analyzed for CPB resistance traits. Somaclonal variation among hybrids was detected for trichome density and resistance to feeding by adult and larval beetles. Somatic hybrids were less resistant than the parents in adult feeding preference trials, but several were more resistant than either parent in larval feeding trials. Future studies are needed to determine whether clones producing both glandular trichomes and leptines express resistance that is more stable than that of clones with only one resistance factor.