Leaf Protein Electrophoresis and Taxonomy of Species of Jatropha L. (Euphorbiaceae)

The systematic relationship existing among members of the all important genus Jatropha was studied using leaf protein electrophoresis. The aim was to identify possible taxonomic importance of the protein profile in the estimation and elucidation of the taxonomic affinity of the six species of Jatropha (Jatropha curcas Linn., J. podagrica Hook., J. gossypifolia Linn., J. mutifida Linn., J. tanjorensis Ellis & Saroja and J. integerrima Linn.) found in Nigeria. The species were screened for total protein banding patterns using gel electrophoresis. Young leaves (0.8 g) of the plants were washed with distilled water and macerated with sterile mortar and pestle in 0.8% Phosphate Buffer-Saline (PBS) containing 0.4 M NaCl at pH 8.0. Results reveal that protein banding pattern was taxon specific. Generic band occurs at 8.3. The highest number of interspecific bands (4) exists between J. podagrica and J. multifida. Variations exist not only in the number of bands but also in the intensity of the bands. Sokal and Sneath coefficient of similarity ranges between 11.1-44.4 %. Single linkage Cluster Analysis (SLCA) of the relative mobility values of the protein in the taxa shows partial agreement with current sub generic and sectional delimitation of the species based on morphology and anatomy of the species.