GENETIC DIVERSITY AND EVALUATION OF MARKERS LINKED TO RESISTANCE AND PUNGENCY GENES IN CAPSICUM SPECIES

No Thumbnail Available
Date
2017
Authors
Adeyemo, O. A.
Ukaonu, C. C.
Agboola, T. D.
Nzoniwu, N. A.
Udoh, B. E.
Kehinde, A. G.
Journal Title
Journal ISSN
Volume Title
Publisher
Nigerian Journal of Genetics
Abstract
The genetic diversity and evaluation of markers linked to resistance and pungency genes will be useful for understanding the level of genetic variation to ensure future genetic resources for crop improvement and conservation. This study of the genetic relationships among 25 cultivars of pepper belonging to Capsicum annuum, Capsicum frutescens and Capsicum chinense collected from some states of Nigeria were assessed with nine simple sequence repeats and ten inter-simple sequence repeats. The SSRs and ISSRs produced an average number of alleles per locus of 4.5 and 9 respectively. The average polymorphic information content obtained with SSR markers was 0.62. Using the genetic distances, dendrograms were produced by the UPGMA method. Based on the SSR data, the grouping of the 25 cultivars of pepper indicated that there is species type discrimination and it also shows the existence of close genetic relationships among them. The relationship among cultivars based on ISSR data appears to show more of close relationship among the pepper species. The Mantel test between two Jaccard‟s similarity matrices gave r = 0.27, showing a moderate fit correlation between SSR and ISSR-based data. An analysis of markers linked to resistance genes revealed that some cultivars evaluated possess alleles against potyviruses (PVY-0, PVY-1) and common strains of Tobacco etch virus (TEV) pathogen resistance. In the present study, 14 Capsicum lines possessed the pungent allele. The molecular markers have helped to understand the level of genetic diversity and alleles of resistance to pathogens and pungency genes that exist among cultivars.
Description
Keywords
Pepper, SSR and ISSR markers, resistance genes, pungency
Citation
Oyenike Arike Adeyemo, Collins Ukaonu Chidimma, Tolu David Agboola, Nnamdi Abiola Nzoniwu, Bright Essien Udoh and Adekunle Gbolaga Kehinde. 2017. Genetic diversity and evaluation of markers linked to resistance and pungency genes in Capsicum species. Nigerian Journal of Genetics. 31(1): 252 -268.