Submitted to: International Symposium on Cucurbits Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: June 8, 2009
Publication Date: September 20, 2009
Citation: Weng, Y. 2009. An Inter-varietal Cucumber Linkage Map with 133 New Microsatellite Markers [abstract]. International Symposium on Cucurbits Proceedings. p. 22.
The cucumber (Cucumis sativus var. sativus L.) recombinant inbred line (RIL) population from inter-variety cross of G421 with H19 has been used extensively in genetic mapping of yield- and fruit quality-related QTLs with molecular markers. However, only ~200 molecular markers, mostly AFLPs and RPADs, have been placed on this map limiting its utility in molecular breeding or map-based gene cloning studies. In the present study, microsatellite markers developed from cucumber whole genome sequences were used for linkage mapping in the G421 × H19 RIL population. In total 960 genomic SSRs were tested, and 821 were able to amplify PCR products in G421 and H19, of which 17.0% (140/821) were polymorphic between the two lines as revealed by 3% agarose gel electrophoresis. Linkage analysis with 46 RILs enabled assignment of 132 of the 140 marker loci into seven linkage groups with a total map length of 888.4 cM. The number of loci mapped in linkage groups 1 through 7 was 10, 9, 25, 14, 32, 34 and 12 respectively. As compared with the SSR map developed from the RIL population of inter sub-specific cross between Gy14 and PI 183967 (C. sativus var. hardwickii Alef), no recombination suppression was observed, and the marker orders supported the notion of possible structural inversions in chromosomes 4 and 6 between the two subspecies. By integration of previously mapped loci, the inter-varietal G421 × H19 linkage map now has 332 molecular markers placed on it.