Allozyme frequency distribution patterns at two gene loci of the phosphoglucomutase and one gene locus of fumarate hydratase enzymes in nine cowpea (Vigna unguiculata (L) Walp) landraces in three agroecological zones

Abstract

Allozyme diversity at the gene loci of the Phosphoglucomutase and Fumarate hydratase enzymes were studied in cowpea landraces,with accession numbers 87/139, 87/142, 87/157, 87/30, 87/37, 87/55, 87/77, 87/81, and 87/83. Leaf protein of the accessions were extracted and subjected to starch gel electrophoresis. Two gene loci and one gene locus were assayed for phosphoglucomutase and fumarate hydratase enzymes, respectively. The two phosphoglu-comutase gene loci were designated PGM1* and PGM2*, with three and four alleles, respectively. The fumarate hydratase gene locus was designated FH1* with three alleles. Mean allele frequencies for PGM1*-1, PGM1*-2, and PGM1*1-3 are 0.470 " 0.011, 0.389 " 0.010, and 0.134 " 0.012, respectively. Mean allele frequencies for PGM2*1-1, PGM2*-2, PGM2*-3, and PGM2*-4 were 0.445 " 0.052, 0.475 " 0.038, 0.062 " 0.019, and 0.017 " 0.010, respectively. Mean allele frequencies FH1*-1, FH1*-2, and FH1*-3, were 0.294 " 0.106, 0.470 " 0.085, and 0.236 " 0.064, respectively. Allele frequencies for PGM1*-1, PGM2*-1 and FH1*-1 were highest in the deciduous forest zone. The alleles PGM1*-2, PGM2*-2 and FH1*-2 were highest in the Guinea savanna zone, while the highest frequencies for alleles PGM1*-3, PGM2*-3, PGM2*-4 and FH1*-3 occurred in the Sudan savanna zone. Alleles PGM2*-3, PGM2*-4 and FH1*-3 showed cline effects with increase in their allelic frequencies from the deciduous forest zone to the Sudan savanna zone; allele PGM2*-1 showed cline effect with an increase in frequency from the Sudan savanna zone to the deciduous forest zone.

JOURNAL OF THE GHANA SCIENCE ASSOCIATION Volume 2 No. 3 (2000) pp. 136-143