Proximate analysis of some Jatropha curcas L. (Jatropha) Germplasm from Sokoto and Kebbi States

Jatropha curcas (Linnaeus) belongs to the family Euphorbiaceae and is closely related to other important cultivated plants like rubber tree and castor. Nigeria being a tropical country has wide variations in climatic and soil conditions and therefore has a wide variety of oil crops such as Jatropha. But the paucity of information on the proximate composition and utilization of its seeds in Nigeria is a problem when it comes to the genetic improvement of the crop. Information about nature and extent of genetic variability present in the Jatropha germplasm and association of various proximate compositions is a pre-requisite in planning successful breeding programme. The objectives of the study were to determine the variation in the proximate composition of some Jatropha curcas L. genotype seeds, determine the correlation among the proximate compositions in the Jatropha and suggest the best genotypes in terms of the proximate composition. The experiment was conducted in the laboratory of Product Development Research Programme of the Institute for Agricultural Research, Ahmadu Bello University, Zaria. Data were collected on the proximate compositions of the seeds: moisture, ash, protein, lipid, fibre and carbohydrate content and analyzed. Phenotypic correlations were computed for all the proximate compositions. Rank summation index was generated to identify the best genotype in terms of the proximate compositions. Significant differences were observed for all proximate compositions studied except the lipid which showed highly significant variation for all the genotypes. Highly significant correlations were observed between protein and lipid content (r = 0.67). Sokoto3 and Kebbi10 ranked first and last with rank summation indices of 14 and 118 respectively. The results obtained indicated the presence of appreciable amount of variability within the genotypes to be exploited for improvement. Sokoto3 was found to be the best genotype in terms of the proximate composition.