ABSTRACT

The study reports the results of analysis of chromosomes of Vigna subterraneap rformed in the mitotic prometaphase and metaphase stages using conventional techniques. The somatic chromosome study was done using the shoot rneristem as the root tips persistently showed very low mitotic indices. The result revealed somatic chromosome number of 2n =22. There was no evidence of polyploidy in any of the four (4) accessions. The chromosome morphology was described on the basis of the centromere position, From the F.% value, it was evident that the different accessions showed wide range of variation in their karyotypes. The F. % range of 33.33 to 50.00 was recorded for Ac-0 I. Ac-02 and Ac-03. They had metacentric and submetacentric chromosomes while Ac-04 had F.% range of 25.00 to 50.00. With the exception of the 9" chromosome pair that was telocentric, the chromosomes were mostly metacentric and submetacentric. The correlation studies between the am, lengths and the chromosome length showed positive and significant relationship apart from AC-02, where the relationship between the short ann and the chromosome length was nonsignificant. Since the accessions were diploid. the uniformity in chromosome number of the four accessions investigated is a clear indication that they may have evolved from a common ancestor, fanning a homogeneous assemblage.