title: Identification of malodorous, a wild species allele affecting tomato aroma that was aelected against during domestication.
abstract: Vegetable cultivation favored the inclusion of pleasant aromas in the produce, whereas unpleasant aromas were selected against. Introgression lines, generated by hybridization of a cultivated tomato (Lycopersicon esculentum) to its wild relative L. pennellii, were used to map quantitative trait loci (QTL) that influence tomato aroma. A marked undesirable flavor was detected by taste panelists in L. pennellii fruits and was related to an introgressed segment from the short arm of chromosome 8. Analysis of the ripe fruits' volatiles of chromosome 8 introgressed lines revealed an up to 60-fold increase in the levels of 2-phenylethanol and phenylacetaldehyde, as compared to the cultivated tomato. This effect was associated with a 10 cM segment originating from the wild species. Although 2-phenylethanol and phenylacetaldehyde have favorable contribution to tomato aroma when present at low levels, phenylacetaldehyde has a nauseating objectionable aroma when present in levels >0.005 ppm. The loss of the ability to produce high levels of phenylacetaldehyde contributed to the development of desirable aroma of the cultivated tomato. The findings provide a genetic explanation for one of the aroma changes that occurred during the domestication of the tomato.
authors.affiliation: Institute of Field and Vegetable Crops, Newe Ya'ar Research Center, Agricultural Research Organization, P.O. Box 1021, Ramat Yishay, Israel.
authors.forename: Yaakov
authors.initials: Y
authors.lastname: Tadmor
authors.forename: Eyal
authors.initials: E
authors.lastname: Fridman
authors.forename: Amit
authors.initials: A
authors.lastname: Gur
authors.forename: Olga
authors.initials: O
authors.lastname: Larkov
authors.forename: Elena
authors.initials: E
authors.lastname: Lastochkin
authors.forename: Uzi
authors.initials: U
authors.lastname: Ravid
authors.forename: Dani
authors.initials: D
authors.lastname: Zamir
authors.forename: Efraim
authors.initials: E
authors.lastname: Lewinsohn
mesh_terms: D000079:Acetaldehyde / Q000031:analogs & derivatives* / Q000032:analysis; D000483:Alleles; D002874:Chromosome Mapping; D017343:Genes, Plant; D018551:Solanum lycopersicum / Q000235:genetics*; D009812:Odorants; D010626:Phenylethyl Alcohol / Q000032:analysis; D012641:Selection, Genetic; D013649:Taste; D014835:Volatilization
chemical_list: D000079:Acetaldehyde; D010626:Phenylethyl Alcohol; C013192:phenylacetaldehyde