Laboratoire de Physiologie et Production Végétale, Université Marien N’GOUABI, Faculté des Sciences et Techniques, BP.69. Brazzaville, Republic of the Congo
Eggplant is a vegetable fruit plant mostly consumed in Congolese daily menus. The low yield observed is due to the low content in mineral element in the soil. The chemical fertilizers used by producers are expensive and harmful to the environment. This study aims to improve the productivity of local eggplant cultivars by supplying chicken manure. Plantlet from Solanum eathiopicum, Solanum eathiopicum gilo, Solanum eathiopicum gilo-anguivi and Solanum macrocarpon are fertilized with 100, 200 and 300g of chicken manure, thus constituting the doses D1, D2 and D3. These treatments are compared to unfertilized one (D0). The experimental design was randomized complete block in three replicates. A block has 45 subplots and 4 plants per subplots were observed in relation to the plant height, neck diameter, the number of leaves per plant and the number of branches. They also relate to the number of fruits per plant, the fruit length and diameter, the average fruit weight. The addition of 200g of chicken manure per pocket significantly improves the vegetative growth of 4 local eggplant cultivars. At this dose, it is noted an early emission of flowers and buds, a high number of blooming flowers and 1176 fruits/plants. The C3 cultivar, S. eathiopicum gilo-anguivi, is more productive than three others. The dose of 300g per pocket was harmful to vegetative growth, it causes flower drop and reduced yield. Chicken manures are an asset to increase eggplant productivity in the tertiary sand of Brazzaville.
Grewia coriacea Mast. (Malvaceae) is fruiting tree of the Congolese spontaneous flora used in traditional pharmacopee to cure several pathologies. Its fruits are clustered and very appreciated by local populations for the jus their produce. They are green when unripe and become blackish red at the gustatory maturity. Given this change of color we aimed at assessing the total polyphenols and flavonoid content in the epicarp, the mesocarp and nuts of the fruits at various stages from physiological maturity, maturiy, early gustatory and gustatory maturity from dosage on the spectrophotometer. Based on the importance of phenolic compounds in treatments of several pathologies, this approach would provide an indication to consumers and trade-therapists using the fruits. Results showed the richness of the phenolic compounds in the fruits of G. coriacea which are more stocked at the gustatory maturity nevertheless the fruit period or the maturity stage considered. The aqueous solution better extracts total polyphenols with 11.47 mg EAG/g MS followed by the hydroethanolic extract with 9.1 mg EAG/g MS. Similarly, the aqueous and hydroethanolic solutions extract very well the total flavonoids with 21.46 mg EAG/g MS and 22.60 mg EAG/g MS respectively. Fruits of G. coriacea can be considered in this study as a source for phenolic compounds which have beneficial effects on the human organism notably in reducing the risk for development of several pathologies.