|Plaisted, Robert - CORNELL UNIVERSITY|
Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 21, 1997
Publication Date: N/A
Interpretive Summary: Nematodes are minute worms that attack potato roots and tubers and cause serious crop losses. Our research has shown that a gene for resistance to nematodes is tightly linked to the production of specific natural defense chemicals in potatoes. These results will aid potato breeders in developing better nematode resistant varieties of potato.
Technical Abstract: High ratios of solavetivone to total sesquiterpenes were previously associated with derivation from a Bolivian accession of potato (Solanum tuberosum ssp. andigena CPC1673) that confers the H1 gene for resistance to Globodera rostochiensis (golden nematode). To test the relationship between solavetivone production and nematode resistance, the inheritance of these traits was determined using four crosses among potato clones that are nematode-susceptible homozygotes or resistant heterozygotes. Progeny from each cross were screened for tuber sesquiterpene production after treatment with arachidonic acid, and for nematode resistance by counting individual cysts on roots of plants inoculated in the greenhouse. Nematode resistance exhibited dominant, single gene segregation. A wide range of sesquiterpene levels and solavetivone ratios was recovered among the progeny, indicating that these are complex traits. There was no correlation between sesquiterpene levels and nematode resistance, but solavetivone ratios of nematode-susceptible and nematode-resistant progeny were significantly different in all four crosses (P <.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. rostochiensis.