GENETIC DIVERSITY AND PHYLOGENETICS OF FOUR RELEASED COWPEA (Vigna unguiculata (L.) Walp) VARIETIES (FUAMPEA-1, FUAMPEA-2, FUAMPEA-3 AND FUAMPEA-4) USING SIMPLE SEQUENCE REPEATS MARKERS

Abstract

Cowpea improvement has continued to play key roles in the quest for national food security. This work elucidated the molecular genetic diversity and phylogenetics among four released cowpea varieties (FUAMPEA-1, FUAMPEA-2, FUAMPEA-3 AND FUAMPEA-4). DNA was extracted from 14 day old seedlings using the CTAB method. A total of nine (9) SSR (Simple Sequence Repeats) markers were employed in DNA amplifications. Binary matrix was generated from banding profiles of gel images and uploaded into the Minitab 17.0 software for analysis. Polymorphic Information Content (PIC) was computed for the primers and cowpea varieties. Cluster analysis was carried out using the Single Linkage method measured on Euclidean Distance. Four primers (CLM1190, CLM0342, RB38 and RB7) produced maximum of two bands each resulting in 15.4% polymorphism and 0.977 Polymorphism Information Content (PIC). Varietal Polymorphic Content (VPC) varied from 15.4% in FUAMPEA-2 as the lowest to 38.5% in FUAMPEA-1 as the highest. FUAMPEA-1 had the lowest genetic similarity index (19.82). Dendrogram further showed that FUAMPEA-2 and FUAMPEA-3 were more closely related than others with about 46.55 similarity index. Therefore, FUAMPEA-1 was the most divergent and genetically diverse variety followed by FUAMPEA-4. These are potential genetic resource material that can used to develop more cultivars when their inherent agronomic traits and genes coding for the traits are identified and tapped.