This research was carried out on the rice farming sites of the agronomic research substation of Finkolo in the sudan-Guinean zone of Mali. The objective was to test the efficiency of the application of some dosage of mineral manure in the production of rain rice. Specifically the study aimed to evaluate the effect of different dosages in the use or the cereal complex and of urea within the agronomic parameters of rice varieties (NERICA 4 and 8). The experimental setup used was a bloc factorial conducted three times. The dosage of 100 and 200 kg ha-1 of the cereal complex to the best performance on the whole parameters measured of the rice. Moreover, the growth in hight and the straw yiel were better due to the application of 100 and 150 Kg ha-1 of urea. The Nerica 8 was more performant in paddy yield compared to Nerica 4. The application of mineral manure should be recommanded in rain rice farming in order to improve the production in the ameliorated varieties because it enhances noticeably the yield. In order to obtain a better efficiency in the use of the mineral manure, above all the nitrogen fertilizer, a suited localisation for the application is required.

Objective: To characterize the weed flora in the corn-growing plots and assess their harmfulness in the Haut-Sassandra region in the center-west of the Ivory Coast.Methodology and results: The weed flora of the maize crop in the Haut-Sassandra region was evaluated using the method called « field tour ».Results: The work made it possible to identify 105 species of weeds belonging to 80 genera distributed in 27 families.The dominant families are: The Poaceae (37,81%), the Asteraceae (10,48%), the Euphorbiaceae (8,57%), the Fabaceae (8,57%) and the Rubiaceae (6,67%). Dicotyledons are in the majority with 67% of species.Agronomically speaking, Croton hirtus, Porophyllump ruderale, Mitracarpus villosus, Digitaria gayana and Brachiara villosa are the most harmful weeds in the area.Conclusion and appliation of the results: This study mmade it possible to characterize the weed flora of maize. The data obtained are necessary for the development of effective control means.