ASSOCIATION BETWEEN SOLAVETIVONE PRODUCTION AND RESISTANCE TO GLOBODERA-ROSTOCHIENSIS IN POTATO

High ratios of solavetivone to total sesquiterpenes were previously as sociated with derivation from a Bolivian accession of potato (Solanum tuberosum ssp. andigena CPC1673) that also confers the H1 gene for res istance to Globodera rostochiensis (golden nematode). To test the rela tionship between solavetivone production and nematode resistance, the inheritance of these traits was determined using four crosses among po tato clones that are nematode-susceptible homozygotes or nematode-resi stant heterozygotes. Progeny from each cross were screened for tuber s esquiterpene production after treatment with arachidonic acid and for nematode resistance by counting individual cysts on roots of plants in oculated in the greenhouse. Nematode resistance exhibited dominant, si ngle-gene segregation. A wide range of sesquiterpene levels and ratios of solavetivone to total sesquiterpenes was recovered among the proge ny, indicating that these are complex traits. There was no correlation between sesquiterpene levels and nematode resistance, but ratios of s olavetivone to total sesquiterpenes of nematode-susceptible and nemato de-resistant progeny were significantly different in all four crosses (p < 0.01 by t tests of least-squares means). These data indicate that a gene or genes that control solavetivone accumulation are located on potato chromosome V close to the H1 locus for resistance to G. rostoc hiensis.