, Volume 208, Issue 1, pp 143–155 | Cite as

Association analysis of cowpea bacterial blight resistance in USDA cowpea germplasm

  • Ainong ShiEmail author
  • Blair BuckleyEmail author
  • Beiquan MouEmail author
  • Dennis Motes
  • J. Bradley Morris
  • Jianbing Ma
  • Haizheng Xiong
  • Jun Qin
  • Wei Yang
  • Jessica Chitwood
  • Yuejin Weng
  • Weiguo Lu


Cowpea bacterial blight (CoBB, Xanthomonas axonopodis pv. vignicola, Xav) is the most important bacterial disease of cowpea (Vigna unguiculata) because it prevalent in all major cowpea growing areas worldwide, and the use of host resistance is the primary method to control this disease. Genetic diversity and association analysis were conducted for CoBB resistance in 249 USDA germplasm accessions, originally collected from 42 countries. Genotyping by sequencing (GBS) was used for single nucleotide polymorphism (SNP) discovery. A total of 1031 SNPs were used for genetic diversity and association analysis in this study. Three well-differentiated genetic populations and admixtures were postulated in the cowpea panel by STRUCTURE 2.3.4 and MEGA 6. Association analysis for CoBB resistance was done using single marker regression, general linear mode, and mixed linear mode using Tassel 5, GAPIT and QGene 4. Four SNP markers (C35046071_1260, C35084634_455, scaffold96328_3387, and scaffold96765_4430) were identified to be strongly associated with CoBB resistance with >70 % selection accuracy. These markers can be utilized in cowpea breeding for CoBB resistance through marker-assisted selection.


Cowpea Vigna unguiculata Bacterial blight Single nucleotide polymorphism (SNP) Genotyping by sequencing (GBS) Association analysis 



This work was supported by USDA-ARS GRIN GERMPLASM EVALUATION PROPOSAL for National Plant Germplasm System (NPGS) by Crop Germplasm Committee (CGC) with Project Number: 6046-21000-011-15. Cowpea germplasm accessions were provide by USDA-ARS at GRIFFIN, GA Station. The cowpea_Genome_0.03.fa (6750 scaffolds or contigs) ( was kindly provided by Dr. Timothy J. Close at University of California Riverside, CA, USA.

Supplementary material

10681_2015_1610_MOESM1_ESM.xlsx (653 kb)
Supplementary material 1 (XLSX 653 kb)


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Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  • Ainong Shi
    • 1
    Email author
  • Blair Buckley
    • 2
    Email author
  • Beiquan Mou
    • 3
    Email author
  • Dennis Motes
    • 4
  • J. Bradley Morris
    • 5
  • Jianbing Ma
    • 1
  • Haizheng Xiong
    • 1
  • Jun Qin
    • 1
  • Wei Yang
    • 1
  • Jessica Chitwood
    • 1
  • Yuejin Weng
    • 1
  • Weiguo Lu
    • 1
  1. 1.Department of HorticultureUniversity of ArkansasFayettevilleUSA
  2. 2.LSU AgCenter, Red River Research StationBossier CityUSA
  3. 3.Crop Improvement and Protection Research UnitUSDA-ARSSalinasUSA
  4. 4.Vegetable Research CenterUniversity of ArkansasAlmaUSA
  5. 5.Plant Genetic Resources Conservation UnitUSDAGriffinUSA

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