Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 31, 1995
Publication Date: N/A
Interpretive Summary: To improve the disease resistance of potato plants, potato breeders are using genetics to incorporate new traits from wild potato species into commercial potato cultivars. This approach, however, is not without its pitfalls, because some wild plants owe their disease resistance to higher levels of toxic compounds than their cultivated relatives. Therefore, we have begun studying the chemistry of a wide variety of new potato varieties. We have found that many new disease resistant varieties produce a different spectrum of compounds than older varieties. Further tests to evaluate the role of these compounds in disease resistance are in progress, and should help breeders to develop disease resistant commercial potato varieties.
Technical Abstract: Rishitin, lubimin and solavetivone were the major sesquiterpenes found in 46 cultivars and breeding selections of potato (Solanum tuberosum L.). Concentrations of total sesquiterpenes were low or undetectable in untreated tuber slices, but ranged from 5 to 101 ug/g fresh weight four days after treatment with the elicitor arachidonic acid. Seven genotypes produced significantly (P<.01) higher sesquiterpene concentrations than Russet Burbank (17 ug/g), a widely grown commercial cultivar. More than half of the genotypes tested were significantly (P<.01) different from Russet Burbank in sesquiterpene composition due to higher ratios of lubimin or solavetivone, both of which are reported to be biosynthetic precursors of rishitin. The highest ratios of solavetivone to total sesquiterpenes were strongly correlated with derivation from S. tuberosum spp. andigena CPC 1673 which confers the H1 gene for resistance to the golden nematode (Globodera rostochiensis).