title: Genetics of flavonoid, carotenoid, and chlorophyll pigments in melon fruit rinds.
abstract: External color has profound effects on acceptability of agricultural products by consumers. Carotenoids and chlorophylls are known to be the major pigments of melon (Cucumis melo L.) rinds. Flavonoids (especially chalcones and anthocyanins) are also prominent in other fruits but have not been reported to occur in melons fruit. We analyzed the pigments accumulating in rinds of different melon genotypes during fruit development. We found that melon rind color is based on different combinations of chlorophyll, carotenoids, and flavonoids according to the cultivar tested and their ratios changed during fruit maturation. Moreover, in "canary yellow" type melons, naringenin chalcone, a yellow flavonoid pigment previously unknown to occur in melons, has been identified as the major fruit colorant in mature rinds. Naringenin chalcone is also prominent in other melon types, occurring together with carotenoids (mainly β-carotene) and chlorophyll. Both chlorophyll and carotenoid pigments segregate jointly in an F(2) population originating from a cross between a yellow canary line and a line with green rind. In contrast, the content of naringenin chalcone segregates as a monogenic trait independently to carotenoids and chlorophyll. Transcription patterns of key structural phenylpropanoid and flavonoid biosynthetic pathway genes were monitored in attempts to explain naringenin chalcone accumulation in melon rinds. The transcript levels of CHI were low in both parental lines, but C4H, C4L, and CHS transcripts were upregulated in "Noy Amid", the parental line that accumulates naringenin chalcone. Our results indicate that naringenin chalcone accumulates independently from carotenoids and chlorophyll pigments in melon rinds and gives an insight into the molecular mechanism for the accumulation of naringenin chalcone in melon rinds.
authors.affiliation: Newe Yaar Research Center, ARO, PO Box 1021, Ramat Yishay 30095, Israel. tadmory@agri.gov.il
authors.forename: Yaakov
authors.initials: Y
authors.lastname: Tadmor
authors.forename: Joseph
authors.initials: J
authors.lastname: Burger
authors.forename: Ilan
authors.initials: I
authors.lastname: Yaakov
authors.forename: Ari
authors.initials: A
authors.lastname: Feder
authors.forename: Smadar E
authors.initials: SE
authors.lastname: Libhaber
authors.forename: Vitaly
authors.initials: V
authors.lastname: Portnoy
authors.forename: Ayala
authors.initials: A
authors.lastname: Meir
authors.forename: Galil
authors.initials: G
authors.lastname: Tzuri
authors.forename: Uzi
authors.initials: U
authors.lastname: Sa'ar
authors.forename: Ilana
authors.initials: I
authors.lastname: Rogachev
authors.forename: Asaph
authors.initials: A
authors.lastname: Aharoni
authors.forename: Hagai
authors.initials: H
authors.lastname: Abeliovich
authors.forename: Arthur A
authors.initials: AA
authors.lastname: Schaffer
authors.forename: Efraim
authors.initials: E
authors.lastname: Lewinsohn
authors.forename: Nurit
authors.initials: N
authors.lastname: Katzir
mesh_terms: D002338:Carotenoids / Q000032:analysis* / Q000235:genetics; D047188:Chalcones / Q000032:analysis / Q000235:genetics; D002734:Chlorophyll / Q000032:analysis* / Q000235:genetics; D028462:Cucumis / Q000737:chemistry* / Q000235:genetics*; D005419:Flavonoids / Q000032:analysis* / Q000235:genetics; D005638:Fruit / Q000737:chemistry*; D005838:Genotype; D010858:Pigmentation; D012333:RNA, Messenger / Q000032:analysis
chemical_list: D047188:Chalcones; D005419:Flavonoids; D012333:RNA, Messenger; D002734:Chlorophyll; D002338:Carotenoids; C027329:naringenin chalcone