Comparison of genomic SSR and EST-SSR markers for estimating genetic diversity in cucumber
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Thirteen genomic microsatellite (gSSR) and sixteen expressed sequence tag (EST)-SSR (eSSR) markers were compared to estimate genetic diversity among 29 cucumber (Cucumis sativus L.) accessions. gSSR markers detected mean 4.46 alleles with a mean polymorphic information content (PIC) of 0.664, against eSSR markers with mean 3.38 alleles and a mean PIC of 0.397. gSSRs amplified more null alleles than eSSRs. Genetic diversity within the accession set was estimated by construction of dendrograms using gSSR or eSSR data. There was a clear consistency between gSSR and eSSR trees in terms of positioning of most cucumber germplasms. gSSR markers could separate various types of cucumber germplasms on the whole, although clustering of some accessions was not based on their geographical origins in eSSR tree. eSSR markers identified an independent sub-cluster containing five accessions resistant to downy mildew, suggesting a probable relationship between eSSRs and disease-resistance trait in cucumber. The Mantel test between gSSR and eSSR matrices revealed a good fit correlation (r = 0.836). The general dendrogram constructed using the combined data of gSSRs and eSSRs was similar to those obtained separately with each marker.
Additional key wordsCucumis sativus dendrograms polymorphic information content
- EG, EO, NC, OP, SC
Europe greenhouse, Europe open-field
- north China
occident processing and south China accessions, respectively
expressed sequence tag microsatellite
expressed sequence tag
polymorphic information content
unweighted pair group method using arithmetic averages
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This work is supported by National Key Technology R & D Program (No. 2009BADB8B02). We are grateful to Prof. Jiancan Feng, College of Horticulture, Henan Agricultural University, for his assistance in the laboratory work on this project.
- Dijkhuizen, A., Kennard, W., Havey, M.J., Staub J.E.: RFLP variation and genetic relationships in cultivated cucumber. — Euphytica 90: 79–87, 1996.Google Scholar
- Jaccard, P.: Nouvelles recherches sur la distribution florale. — Bul. Soc. Vaudoise Sci. Nat. 44: 223–270, 1908.Google Scholar
- Pitrat, M., Chauvet, M., Foury, C.: Diversity, history, and production of cultivated cucurbits. — Acta Hort. 492: 21–28, 1999.Google Scholar
- Rohlf, F.J.: NTSYS-pc: Numerical Taxonomy and Multivariate Analysis System, Version 2.1. — Exeter Publications, New York 2000.Google Scholar
- Watcharawongpaiboon, N., Chunwongse, J.: Development and characterization of microsatellite markers from an enriched genomic library of cucumber (Cucumis sativus). — Plant Breed. 127: 74–81, 2008.Google Scholar