The cultivation of maize, the second crop after cassava in terms of consumption in the Kisangani region, is faced with edaphic constraints aggravated by itinerant slash and burn agriculture. Our study proposes the use of biochar enriched with compost tea to remove these constraints. The chemical characteristics of biochar are: 2.48 to 4.68 c. moL.g-1 for the acid functions; 0.64 to 1.03 c. moL.g-1 for basic functions; 8 for the pH at the point of zero load; 64 to 103% for retention capacity; 875.3 mg.g-1 for the iodine index. From a microbiological point of view, out of around thirty isolates, the majority of Gram-negative bacilli corresponding to the genera Nitrosomonas, Azotobacter and Nitrobacter were identified. The experimental site was arranged according to the Device in complete random blocks with 4 blocks and 4 plots of dimensions 6 m x 4.5 m each corresponding to the following 4 treatments: T0 (witness); T1 (Biochar over 2 mm in diameter); T2 (Biochar 2 mm in diameter); T3 (Biochar 2 mm in diameter and enriched with compost tea). The average yields obtained increase during 8 cropping seasons under all the treatments and vary from 2.38 t.ha-1 under T0 to 7.39 t.ha-1 under T3. They are relatively higher in the dry season than in the rainy season with an average increase of around 18% and a marginal rate of return for grain maize of 4.4 under T3. Compost tea-enriched biochar, due to its resilience, with substantial aftereffects is an important input for climate-smart agriculture.

The poor management of soil fertility is the major edaphic constraint in the production of Okra, a vegetable highly appreciated by consumers in Kisangani. The objective of our study is to test the different combinations of organic manure in order to determine the most efficient ones on the yield of two varieties of okra in urban agriculture in Kisangani. Okra cultivation is seen as a climate-resilient and income-generating activity. The different treatments are determined in relation to the varieties studied. For the Indiana variety: T0, T1, T2 and T3 represent the control, the biochar, the compost tea and the biochar*compost tea combination respectively. The same treatments apply to the Clemson spineless variety. The experimental device adopted is that of split plot with 3 repetitions. The response of the test plant to the treatments applied was assessed on all the plants except the border plants. The results of the experimental treatments, the relationships between the biological parameters of different populations were respectively compared and determined. Yields vary by variety and treatment. Yields of the Indiana variety are 47.4 t.ha-1 under biochar associated with compost tea against 33.8 t.ha-1 under Clemson spineless. The marginal rate of return for the Indiana variety is 4.4 under the biochar*compost tea combination versus 2.1 for the Clemson spineless variety. Biochar combined with compost tea is proving successful in urban okra farming in Kisangani.