Beyegue Djonko H.^1,, Tatang Tadjufo A.¹, Mvondo-Awono J.P.², Gafe Pelap H.¹, Tankou C.M.¹

Benefits associated with cover crops in direct seeding mulch-based cropping systems (DMC) often depend on the establishment of a highly productive cover crop community. The objective of this study was to assess biomass production for the implementation of DMC and its efficiency based on Land Equivalent Ratios (LER) of Brachiaria ruziziensis and Crotalaria retusa grown in different cropping systems on an Andosol in the Western Highlands of Cameroon. The six treatments were pure stands and combinations of one or two lines of each cover crop. These were assigned to experimental units in a randomized complete bloc design with four replications. Biomass production, ability to start DMC and Land Equivalent Ratios (LER) were used to compare treatments. B. ruziziensis produced 10.51 t DM ha^-1 in pure stands and 2.9 to 5.37 t DM ha^-1 in intercropping. C. retusa produced 5.03 t DM ha^-1 in pure stands and 2.88 to 5.28 t DM ha^-1 in intercropping. There were highly significant differences (p < 0.01) among treatments for total biomass production. Biomass production was significantly higher when two lines of B. ruziziensis were associated with a single line of C. retusa. Intercropping one line of B. ruziziensis and one line of C. retusa was the only combination that could not allow the implementation of DMC the following season. LER larger than 1 for the other intercropping indicated their superiority compared to pure stands. Growing B. ruziziensis and C. retusa during the first season with one line of one species and two lines of the other species, or two lines of each crop species were considered appropriate for the implementation of DMC. Results provided a basis for DMC implementation using intercropping of B. ruziziensis and C. retusa as cover crops during the first cropping season. Further studies are necessary to evaluate the residual effects of the biomass produced.

direct seeding mulch-based cropping systems (DMC), Brachiaria ruziziensis, Crotalaria retusa, intercropping, cover crops, biomass, LER (Land Equivalent Ratio)