Potential of Aqueous Extract of Jatropha curcas on the Control of Post-harvest Rot of Sweet Orange (Citrus sinensis L.) Fruits in Wukari

The study was conducted in Wukari Local Government Area of Taraba State, located in North-Eastern region of Nigeria on Longitude 9.783˚E and Latitude 7.850˚N. A total of ninety (90) sweet orange fruits (Citrus sinensis) were collected from three different markets within Wukari town between the months of March 2018 and June 2018. Observation for the level of fungal growth and fruit rot was made daily for 7 days and results were recorded, percentage rot severity was determined. Wukari New Market had the highest percentage incidence in the study area (83 %), followed by Wukari Yam Market (66.7 %). The least rot incidence was recorded in Wukari Old Market (60 %). Among the three isolates, A. niger causes the most severe rot. Mycelia covering up to 85.8%, the pathogenic effect was rated highly pathogenic. While Aspergillus sp. causes least severe rot with mycelia covering up to 39.9%, the pathogenic effect was rated moderately resistance. Leaves and seeds of the test plant were thoroughly washed, air dried and grinded separately into a fine powder using mortar and pestle. For seeds extraction, four different dilution concentrations were prepared by adding 5g, 10g, 15g, and 20g of the fine powder into a 100mls distilled water separately in a 250ml beaker. It was left to stand for 24 hours and then filtered through three fold of sterile cheesecloth to obtain crude aqueous extracts. For leaves extraction, only the highest dilution concentration of the seed extraction was used. The phytochemical characteristics of the plants investigated are summarized as Alkaloid, Glycosides, Terpenoids, and Sapronins were present in seed and leaf extracts. Flavonoids were absent in both seed and leaf extracts. Tannins, Reducing sugar and Phenols are only present in the leaf extract. The design was a Completely Randomized Design (CRD) with three replicates. The variables considered were fungal isolates and concentrations of the extracts. All data were analyzed statistically using the Statistical Package for Social Sciences (SPSS) program. Means that are significant were separated by the test of Least Significance Difference (LSD). The study recommends that this promising plant extract be further evaluated in multi-location that share same agroecology zone