On the grounds of the classification by Marechal, Vigna vexillata belongs to the genus Vigna, subgenus Plectotropis, section Plectotropis. It is a wild species distributed in Africa and Asia which is highly resistant to the pod sucking bug and moderately to the legume pod borer. V. vexillata has raised researchers' interest because some of its accessions are highly resistant to the storage weevil which attacks cultivated cowpea V. unguiculata (subgenus Vigna, section Catiang). In previous studies, V. vexillata and other wild Vigna species were compared with cowpea on the basis of isozyme variability. This research has emphazised that cowpea and V. vexillata although showing a high genetic distance, are isozymically closer to each other than V. unguiculata is to other species belonging to the section Catiang. In order to go deeply into the genetic relationships within V. vexillata, 43 accessions, each with 6-7 individuals, were subjected to starch gel electrophoresis and intraspecific isozyme variability was evaluated. A tris/citrate buffer pH 7.5 containing L-cystine, L-ascorbic acid and polyvinylpyrrolidone 40,000, was used for isozyme extraction from young leaves; extracts were aliquoted and kept at -80°C. Isozyme variations at GOT, LAP, ME, PGM, SKDH, 6PGDH, IDH, MDH SOD and PGI loci were studied. For the electrophoretic run, a buffei composed of histidine/citric acid pH 6.5 or lithium hydroxide/borate pH 8.4 was utilised. The former was used for SKDH, G6PDH, IDH, MDH and SOD. and the latter for GOT, LAP, ME, PGM and PGI. Over 19 regions of activity were scored, and polymorphism arnon^ accessions was observed for nine enzyme systems: GOT, LAP, ME, 6PGDH IDH, MDH, SOD, SKDH and PGI. PGM was monomorphic. Allozyme frequencies were used for statistical analysis to calculate Nei'; genetic distance and diversity parameters. A UPGMA dendrogram based or the genetic distances was constructed.
Intraspecific relationships in Vigna vexillata based on isozyme variation
Sonnante G;Perrino P
1995
Abstract
On the grounds of the classification by Marechal, Vigna vexillata belongs to the genus Vigna, subgenus Plectotropis, section Plectotropis. It is a wild species distributed in Africa and Asia which is highly resistant to the pod sucking bug and moderately to the legume pod borer. V. vexillata has raised researchers' interest because some of its accessions are highly resistant to the storage weevil which attacks cultivated cowpea V. unguiculata (subgenus Vigna, section Catiang). In previous studies, V. vexillata and other wild Vigna species were compared with cowpea on the basis of isozyme variability. This research has emphazised that cowpea and V. vexillata although showing a high genetic distance, are isozymically closer to each other than V. unguiculata is to other species belonging to the section Catiang. In order to go deeply into the genetic relationships within V. vexillata, 43 accessions, each with 6-7 individuals, were subjected to starch gel electrophoresis and intraspecific isozyme variability was evaluated. A tris/citrate buffer pH 7.5 containing L-cystine, L-ascorbic acid and polyvinylpyrrolidone 40,000, was used for isozyme extraction from young leaves; extracts were aliquoted and kept at -80°C. Isozyme variations at GOT, LAP, ME, PGM, SKDH, 6PGDH, IDH, MDH SOD and PGI loci were studied. For the electrophoretic run, a buffei composed of histidine/citric acid pH 6.5 or lithium hydroxide/borate pH 8.4 was utilised. The former was used for SKDH, G6PDH, IDH, MDH and SOD. and the latter for GOT, LAP, ME, PGM and PGI. Over 19 regions of activity were scored, and polymorphism arnon^ accessions was observed for nine enzyme systems: GOT, LAP, ME, 6PGDH IDH, MDH, SOD, SKDH and PGI. PGM was monomorphic. Allozyme frequencies were used for statistical analysis to calculate Nei'; genetic distance and diversity parameters. A UPGMA dendrogram based or the genetic distances was constructed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
