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Studies on the pathological evaluation and nutritional composition of golden melon was carried out in the Plant Pathology and Food Science and Technology Laboratories in the Rivers State University. The freshly harvested fruits of the golden melon had high amount of moisture (58±0.04), sucrose, total solid, lipid with very low ash (0.56±0.00). Mineral composition analysis also revealed high amount of calcium (98.5±0.01), moderate quantity of potassium, and low amount of phosphorus (21.4±0.00). Vitamins A and C were also present in the fruits. Other components found were lactic acid and saponnins which occurred in minute quantities.Pathological evaluation of the associated fungi showed that five different fungi with varying degrees of incidence were associated with the spoilage of the fruits of golden melon. These fungi were Botrytis cinerea (60%), Aspergillus flavus(30%), Aspergillus niger and Aspergillus tamari (5%) respectively while Muccor species recorded the highest incidence (70%). However, all the fungal isolates were found to be pathogenic causing soft rot characterized by oozing of water with offensive odour.

Research study was carried out to assess the biocidal effect of aqueous extracts of Curcuma longa, Zingiber officinale, Citrus limon peel and synthetic fungicide Mancozeb against Rhizopus stolonifer using the poisoned food technique on PDA. Various concentrations (50, 75, and 100%) of extracts from the rhizomes of C. longa, Z. officinale, the peel of C. limon and Mancozeb (0.002%) significantly inhibited the mycelia growth of R. stolonifer after 3 days. Effects of the synthetic fungicide (Mancozeb) comparative to the plant extracts were also determined. Although the extracts showed varying degrees of antifungal efficacy, 100% concentration of Z. officinale (58.96%) proved to be more potent against R. stolonifer than the other plant extracts but was lower and significantly different when compared with Mancozeb (73.31%) at (P≤0.05) after 3 days. Extracts of C. longa and C. limon peel showed a lower inhibition level ranging from 45.01% to 56.98% and 9.57% to 18.73% respectively and were significantly different when compared with Mancozeb at (P≤0.05). Inhibition of fungal growth increased with a corresponding increase in extract concentration and days. The plant leaf extracts effectively inhibited the mycelial growth of pathogen in vitro after 3 days. In vivo study was carried out using spore suspensions of R. stolonifer. Fresh, healthy and surface sterilized Irish potato tubers were inoculated with 6.4 x 104 spores/ml and treated with aqueous extracts of C. longa, Z. officinale and C. limon peel after 24 hours. The result showed that all plant extracts had significant effect on disease severity in tubers inoculated with R. stolonifer. However, 100% concentration of Z. officinale gave the best rot reduction caused by R. stolonifer with severity score of 0.33 but it was not significantly different at (p<0.05) from mancozeb which had a severity score of 0.67. However, they were significantly different at (p<0.05) from the inoculated control (3.33). There were variations in weight loss but no significant difference was observed among the various treatment methods adopted.

Antifungal property of A. paniculata on fungal isolates from Citrullus colocynthis was investigated. Citrullus colocynthis were bought from traders in a major market in Abia State, Nigeria. The melon seeds were first cleaned and disinfested by keeping them in a freezer at -50C for 7 days to kill all hidden infestations. The disinfested seeds were dried in a Gallenkamp oven at 40oC for 4 hours before they were stored in plastic sterile containers with tight lids. Fresh plant of A. paniculata was collected from botanical garden of the Rivers State University and was identified in the botany department. The leaves of the plant were shade dried and blended into fine powder. Twenty grams (20g) of the powdered leaves was extracted using methanol and ethanol. The filtrate was evaporated and the resulting crude extract was used for antifungal sensitivity test. Fungi associated with rotted C. colocynthis were identified using standard microbiological methods. The antifungal activity of the extracts was carried out using the well in agar diffusion method. In this method, 48 hours old fungal isolate was inoculated on dried Sabouraud Dextrose Agar plates in duplicates. five wells were bored using sterile 6mm cork borer on the dried seeded plates before 0.2ml of the different concentrations of 100, 50, 25, and 12.5mg/ml of the methanol extracts were transferred into the wells using sterile pipettes. Aspergillus flavus, Rhizopus arrhizus, Aspergillus niger, Rhizopus sp and Mucor sp were identified from the melon seeds. The zone diameters of methanolic extract of A. paniculata on Rhizopus arrhizus, A. niger, A. flavus, Rhizopus sp and Mucor sp were 11.50±0.71, 19.50±0.71, 34.50±0.71, 15.00±0.00 and 17.00±0.00mm, respectively. The zone diameters of ethanolic extract of A. paniculata on Rhizopus arrhizus, A. niger, A. flavus, Rhizopus sp and Mucor sp were 0.00±0.00, 16.50±0.71, 34.50±0.71, 20.50±0.71 and 0.00±0.00mm, respectively. There were significant differences (P ≤ 0.05) in the antifungal activity of the extract across the fungal isolates. The antifungal activity of the leave extracts showed that the ethanolic extract and the methanolic extract were very active on the fungal isolates and the antifungal activities of the extract was greatly influenced by the concentration of the extract, with higher concentrations of extract having high zone diameter.