Identification of varieties based on only morphological traits is limited by the influence of environment on such morphological traits. Deoxyribonucleic acid (DNA) fingerprinting offers an efficient system of identifying varieties at the DNA level without any environmental interference. This work used 20 Simple Sequence Repeat (SSR) markers to characterise twenty-two cowpea [Vigna unguiculata (L.) Walp] varieties for the purposes of varietal protection and further assessed for genetic diversity. This study was conducted at the Biotechnology laboratory of Council for Scientific and Industrial Research-Crops Research Institute, Ghana (CSIR-CRI). The varieties were made up of 15 cultivars released by CSIR-CRI, Ghana, 5 cultivars released by CSIR-Savannah Agricultural Research Institute, Ghana (SARI), 1 advanced line, 1 landrace and 1 exotic variety. Nineteen out of the 20 SSR markers used in this study were polymorphic. These polymorphic primers generated a range of 1 to 6 alleles per primer with polymorphic information content (PIC) varying from 0.107 (SSR-6608) to 0.656 (SSR-6613). Allele frequency ranged from 0.136 (SSR- 6371) to 0.841 (SSR-6608) with mean of 0.445. With the aid of Darwin software, dissimilarity matrix and a dendrogram were generated from the molecular data to evaluate and group the varieties based on genetic resemblance. Three pairs of varieties (Agyenkwa and Adom; Hewale and Ayiyi; Zamzam and Hewale) recorded the highest genetic distance of 0.652 each. The genetic information gathered for each variety has been made available to the breeding institutions. The genetic diversity detected among the varieties fingerprinted will be helpful to plant breeders in selecting parents for future cowpea improvement programmes.
Souza, R.P., Machado, E.C., Silva, J.A.B., Lagoa, A.M.M.A. and Silveira, J.A.G. (2004) Photosynthetic Gas Exchange, Chlorophyll Fluorescence and Some Associated Metabolic Changes in Cowpea (Vigna unguiculata) during Water Stress and Recovery. Environmental and Experimental Botany, 51, 45-56. https://doi.org/10.1016/S0098-8472(03)00059-5
Singh, B.B. and Ajeigbe, H. (2007) Improved Cowpea-Cereals-Based Cropping Systems for Household Food Security and Poverty Reduction in West Africa. Journal of Crop Improvement, 19, 1-2. https://doi.org/10.1300/J411v19n01_08
International Fund for Agricultural Development, IFAD (2000) Report and Recommendation of the President to the Executive Board on Proposed Technical Assistance Grants for Agricultural Research and Training by CGIAR-Supported International Centres. 69/R.27.
Xiong, H., Shi, A., Mou, B., Qin, J., Motes, D., Lu, W., Ma, J., Weng, Y., Yang, W. and Wu, D. (2016) Genetic Diversity and Population Structure of Cowpea (Vigna unguiculata L. Walp). PloS One, 11, e0160941. https://doi.org/10.1371/journal.pone.0160941
Senior, M.L., Murphy, J.P., Goodman, M.M. and Stuber, C.W. (1998) Utility of SSRs for Determining Genetic Similarities and Relationships in Maize Using an Agarose Gel System. Crop Science, 38, 1088-1098. https://doi.org/10.2135/cropsci1998.0011183X 003800040034x
Badiane, F.A., Gowda, B.S., Cisse, N., Diouf, D., Sadio, O. and Timko, M.P. (2012) Genetic Relationship of Cowpea (Vigna unguiculata) Varieties from Senegal Based on SSR Markers. Genetics and Molecular Research, 11, 292-304. https://doi.org/10.4238/2012.February.8.4
Wamala, E.N., Muoma, J. and Wekesa, C. (2016) Genetic Diversity of Cowpea (Vigna unguiculata (L.) Walp.) Accession in Kenya Gene Bank Based on Simple Sequence Repeat Markers. International Journal of Genomics, 1-5. http://doi.org/10.1155/2016/8956412
Diouf, D. and Hilu, K.M. (2005) Microsatellite and RAPD Markers to Study Genetic Relationships among Cowpea Breeding Lines and Local Varieties in Senegal. Genetic Resources and Crop Evolution, 52, 1957-1967.
Sawadogo, M., Ouedraogo, J.T, Gowda, B.S. and Timko, M.P. (2010) Genetic Diversity of Cowpea (Vigna unguiculata L. Walp.) Cultivars in Burkina Faso Resistant to Striga gesnerioides. African Journal of Biotechnology, 9, 8146-8153. https://doi.org/10.5897/AJB10.1175
Adetiloye, I.S., Ariyo, O., Alake, C.O., Oduwaye, O. and Osewa, S. (2013) Genetic Diversity of Some Selected Nigerian Cowpea Using Simple Sequence Repeats (SSR) Marker. African Journal of Agricultural Research, 8, 586-590. http://www.academicjournals.org/ajar
Doumbia, I.Z., Akromah, R.A. and Asibuo, J.Y. (2014) Assessment of Cowpea Germplasms from Ghana and Mali Using Simple Sequence Repeat (SSR) Markers. International Journal of Agriculture and Forestry, 4, 118-123.
Botstein, D., White, R.L., Skolnick, M. and Davis, R.M. (1980) Construction of a Genetic Linkage Map in Man Using Restriction Fragment Length Polymorphisms. The American Journal of Human Genetics, 32, 314-331.
Afiukwa, C.A., Kunert, K.J., Vorster, J., Cullis, C.A. and Ubi, B.E. (2011) Microsatellite Association with Seed Protein Content and Flowering Time in Nigerian Cowpea Cultivars. African Journal of Biotechnology, 10, 18064-18064.
Choumane, W., Winter, P., Weig, F. and Kahl, G. (2000) Conservation and Variability of Sequence Tagged Microsatellites Sites (STMSs) from Chickpea (Cicer aerietinum L.) within the Genus Cicer. Theoretical and Applied Genetics, 101, 269-278. https://doi.org/10.1007/s001220051479