GROWTH AND YIELD OF MAIZE ALLEY CROPPED WITH LEUCAENA-LEUCOCEPHALA AND FAIDHERBIA-ALBIDA IN MOROGORO, TANZANIA

This study examined the effect of alley cropping of Leucaena leucoceph ala and Faidherbia albida on wood biomass, maize grain yield and soil nitrogen status. The treatments were: trees planted alone at 1 x 5 m s pacing; trees intercropped with maize and a sole maize crop. Mulch bio mass averaged 6.18 and 0.97 t ha(-1) for L. leucocephala and F. albida , respectively. Corresponding wood production was 1.71 and 1.11 t ha(- 1). Both total N and inorganic N (NO3--N plus NH4+-N) were higher unde r F. albida and lowest under L. leucocephala. Similarly, foliar N conc entration in maize was higher in plots intercropped with F. albida and least in L. leucocephala intercropping. Maize grain yield was little affected by the tree intercrop as competition for resources was reduce d through periodic pruning and clean weeding. There was no gain in mai ze grain yield due to the presence of L. leucocephala and F. albida. T hese results suggest that alley cropping in Gario is justified for woo d production but not for increasing maize grain yield.