[01] Kaanjo Tersoo, Department of Botany, University of Agriculture Makurdi, Makurdi, Nigeria. [02] Iheukwumere Charles Chidozie, Department of Botany, University of Agriculture Makurdi, Makurdi, Nigeria. [03] Omoigui Lucky Osabuohien, Department of Plant Breeding and Seed Science, University of Agriculture Makurdi, Makurdi, Nigeria. [04] Olasan Joseph Olalekan, Department of Botany, University of Agriculture Makurdi, Makurdi, Nigeria. [05] Ugbaa Macsamuel Sesugh, Department of Plant Breeding and Seed Science, University of Agriculture Makurdi, Makurdi, Nigeria.

This study was carried out to show the usefulness of SSRs markers in characterizing tomato genotypes and to provide vital information to the geneticists for genetic improvement through development of better tomato varieties with increased fruit yield and quality. A total of 22 tomato accessions were planted in a 4 liter plastic container at University of Agriculture Makurdi screen house. 6 SSR primers were used for the characterization at the Molecular Biology Laboratory of University of Agriculture Makurdi. CTAB protocol for DNA extraction was used to obtain DNA from 23 day old leaves of accessions and amplified via PCR in a thermo-cycler. PCR products were run on 2.5% agarose gel stained with ethidium bromide and visualized under UV light. The bands formed were scored in a binary pattern for analysis. Result revealed a total of 126 bands generated across the accessions with Polymorphic Information Contents values of the SSR primers ranged from 0.703 to 0.967 with a mean value of 0.866 which shows that, they are highly informative for genetic analysis. Cluster analysis grouped the tomato accessions into three distinct clusters based on Euclidean correlation coefficient distance with cluster I, II and III having 42%, 40% and 14.0% of genetic similarity respectively. It also revealed a total of five pairs of duplicates, reducing the total number of genotypes to 5 which indicate that a very low genetic diversity existed among the genotypes obtained in these regions. The results obtained in this study will serve as a guide to agronomists and geneticists in germplasm management and improvement of tomato by intercrossing genotypes belonging to cluster III (NGB-00722 and Akeakpev) and cluster II (Roma VF, Tropimech and Mngishim) to create a suitable genotype with increased fruit yield and quality to enhance tomato production that will be helpful in the development of rural agro-industries in North central and Western Nigeria.

Characterization, Tomato, SSR, Polymorphism and Intercrossing

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