Réhabilitation de la fertilité des sols par usage des bioressources (Crotalaria juncea L. et Brachiaria ruziziensis G.&E.) en zone cotonnière de l’Extrême-Nord, Cameroun

Abstract : One of the major challenge of the international community is to solve the problem of crop yield loss and food insecurity, attributed to the abandon of agricultural soils due to erosion and loss of their fertility. The present work is involved with objective to contribute to agroecological rehabilitation of soil fertility through the direct seeding mulch-based cropping system (DMC). To conduct this work, the experimental plots were conducted in cotton zone of Far-North of Cameroon (Kodek and Zouana), on randomized Fischer plots design with 7 modalities and 4 repetitions with bioresource Crotalaria juncea under maize; and in real production milieu with Brachiaria ruziziensis under cotton, concerning 50 farmers in Far-North Cameroon. The physical, chemical and biological soil samples’ characteristics were analyzed, with also the production parameters of Crotalaria, maize and cotton. The soil analysis shows that in the two experimental sites, soils are sandy-silt at 20 cm depth and the proportion of coarse soil elements is weak in Kodek (12.90%) but important in Zouana (42.03%). There is increase in organic matter content on soil covered by Crotalaria juncea but less than the ideal content 5% (1.38 to 2.09% in Kodek and 1.67 to 2.24% in Zouana) and biological activity is more intensive; structural stability, water and minerals retention capacity are also improved. The C/N ratio varies from 13.30 to 30.31 in Kodek and from 16.00 to 24.75 in Zouana. The CEC at pH7 varies from 9.12 to 13.3 meq/100 g in Kodek and from 7.6 to 12.18 meq/100g in Zouana. There is also fined that 85% of Crotalaria juncea plants in Kodek and 75% in Zouana have nodules, and respectively 6.71 and 5.60 nodules/plant and then 61.96% and 51.22% efficacious nodules, having leghemoglobine. The mean height of Crotalaria juncea, is 1.81 and 2.41 m; the mean plant density is 165503 and 170601 plants/ha; and total dry biomass is 19.03 and 15.74 tons/ha respectively in Kodek and Zouana. The nitrogen fertilizer replacement value obtained from exudates on Crotalaria juncea-maize (CM) association system is 40 and 38 kg N/ha; and value obtained on mulch of Crotalaria juncea (C) after partial mineralization is 196 and 184 kg N/ha respectively on Kodek and Zouana sites. The maize yield improvements are obtained on DMC compared to reference witness unfertilized plot (N0) both in association (CM) 14.08% (2638.63 against 2312.87 kg/ha) in Kodek and 13.89% (2778.53 against 2439.69 kg/ha) in Zouana; and on mulch (C): 38.03% (3192.42 against 2312.87 kg/ha) in Kodek and 34.72% (3286.80 against 2439.69 kg/ha) in Zouana. In the farmer’s conditions, yield gain of cotton on Brachiaria ruziziensis in DMC is 19.43% compared to reference (1506.20 against 1261.44 kg/ha). Besides, there is reduction of work time and production cost in DMC and also, the improvement of net added value compared to witness. Hence, the DMC contribute to rehabilitate the degraded soil fertility and to ameliorate the crop yield. However, the public service support and the actor’s consultation on soil and biomass conservation will enhance this productive and environment protective system.
Complete list of metadatas

Cited literature [275 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02305183
Contributor : Taïda Pierre Hinimbio <>
Submitted on : Thursday, October 3, 2019 - 7:13:56 PM
Last modification on : Saturday, October 5, 2019 - 1:10:08 AM

File

Thèse Doctorat PhD Hinimbio.p...
Files produced by the author(s)

Identifiers

  • HAL Id : tel-02305183, version 1

Collections

Citation

Taïda Pierre Hinimbio. Réhabilitation de la fertilité des sols par usage des bioressources (Crotalaria juncea L. et Brachiaria ruziziensis G.&E.) en zone cotonnière de l’Extrême-Nord, Cameroun. Agronomie. Université de Maroua (Cameroun), 2019. Français. ⟨tel-02305183⟩

Share

Metrics

Record views

63

Files downloads

20