A consensus linkage map identifies genomic regions controlling fruit maturity and beta-carotene-associated flesh color in melon (Cucumis melo L.).
The nutritional value and yield potential of US Western Shipping melon (USWS; Cucumis melo L.) could be improved through the introgression of genes for early fruit maturity (FM) and the enhancement of the quantity of beta-carotene (QbetaC) in fruit mesocarp (i.e., flesh color). Therefore, a set of 116 F(3) families derived from the monoecious, early FM Chinese line 'Q 3-2-2' (no beta-carotene, white mesocarp) and the andromonoecious, late FM USWS line 'Top Mark' (possessing beta-carotene, orange mesocarp) were examined during 2 years in Wisconsin, USA to identify quantitative trait loci (QTL) associated with FM and QbetaC. A 171-point F(2-3) based map was constructed and used for QTL analysis. Three QTL associated with QbetaC were detected, which explained a significant portion of the observed phenotypic variation (flesh color; R (2) = 4.0-50.0%). The map position of one QTL (beta-carM.E.9.1) was uniformly aligned with one carotenoid-related gene (Orange gene), suggesting its likely role in QbetaC in this melon population and putative relationship with the melon white flesh (wf) gene. Two major (FM.6.1 and FM.11.1; R (2) >or= 20%) and one minor QTL (FM.2.1; R (2) = 8%) were found to be associated with FM. This map was then merged with a previous recombinant inbred line (RIL)-based map used to identify seven QTL associated with QbetaC in melon fruit. This consensus map [300 molecular markers (187 co-dominant melon and 14 interspecific; 10 LG)] provides a framework for the further dissection and cloning of published QTL, which will consequently lead to more effective trait introgression in melon.
Cuevas
H E
HE
Department of Plant Breeding and Plant Genetics, University of Wisconsin-Madison, Madison, WI, USA. hcuevas@uga.edu
Staub
J E
JE
Simon
P W
PW
Zalapa
J E
JE
D000704:Analysis of Variance; D002874:Chromosome Mapping; D028463:Cucumis melo / Q000235:genetics* / Q000254:growth & development; D004843:Epistasis, Genetic; D020224:Expressed Sequence Tags; D005638:Fruit / Q000235:genetics* / Q000254:growth & development*; D017343:Genes, Plant; D018745:Genome, Plant / Q000235:genetics*; D018598:Minisatellite Repeats; D010858:Pigmentation / Q000235:genetics*; D040641:Quantitative Trait Loci / Q000235:genetics; D012044:Regression Analysis; D026801:Synteny / Q000235:genetics; D019207:beta Carotene / Q000235:genetics / Q000378:metabolism*
D019207:beta Carotene