Microsatellites markers associated with resistance to flower bud thrips in a cowpea F2 population derived from genotypes TVU-123 and WC36
Loading...
Date
2018
Journal Title
Journal ISSN
Volume Title
Publisher
African Journal of Biotechnology
Abstract
Breeding for resistance to flower bud thrips (Megalurothrips sjostedti) in cowpea has been hindered by
the quantitative nature of resistance. To identify simple sequence repeat (SSR) markers associated with
resistance to flower bud thrips that could be used for marker-assisted breeding, a F2 population was
generated from a cross between genotypes TVU-123 (resistant) and WC36 (susceptible). The population
was evaluated for thrips damage scores, thrips counts, and pods number per plant under artificial
infestation. Sixty-six microsatellites markers were screened between the two parental lines and seven
polymorphic markers were used for genotype 100 F2 plants. Single marker analysis was used to
evaluate an association between the markers and traits. Transgressive segregation among the F2 plants
for resistance to flower thrips was observed. A significant negative relationship was observed between
thrips damage scores and pods number per plant. Markers CP37/38 and CP215/216 were significantly
associated with thrips damage scores and thrips counts, respectively. The two markers explained 7 and
11.2% of the total variation in thrips damage scores and thrips counts with positive and negative
effects, respectively. Mainly additive gene effects were observed. A more detailed study using more
markers on these loci should provide better understanding of this complex trait.
Description
Keywords
Cowpea, Single marker analysis, Polymorphism, Simple sequence repeat (SSR) markers
Citation
Agbahoungba, S., Karungi, J., Sadik, K., Gibson, P., Edema, R., Assogbadjo, A. E., & Rubaihayo, P. R. (2018). Microsatellites markers associated with resistance to flower bud thrips in a cowpea F2 population derived from genotypes TVU-123 and WC36. African Journal of Biotechnology, 17(25), 767-778. DOI: 10.5897/AJB2018.16480