This study evaluates the productivity of cotton and sorghum in a shea-based
agroforestry system in northernBenin.
Tomboutou and Gounarou villages were respectively selected in the shea
parklands of Bembèrèkè and Kandi. Within each parkland and village, three
classes of tree crown diameter for shea trees (4 -8
m, 8 -10 mand <10 m), were
defined after the inventory phase. In each class of crown diameter, three trees
intercropped with cotton and sorghum were randomly selected among the 18 to 21
farms in each of the two village territories. The crops were planted in
accordance with the technical procedures recommended by the national
agricultural extension service. The following data was collected for sorghum
and cotton on1 m2area
under the crown and outside the crown, in the four cardinal directions of each
sample tree: crop height, fresh biomass per crop and buds per cotton plant.
Data analysis revealed a very significant difference in the variables (height
of sorghum and cotton, biomass of cotton and sorghum, number cotton buds) between
the areas under the crown and those outside the crown (P < 0.01). The
productivity variables for sorghum, i.e.,
average plant height and average biomass, dropped by 9.75% and 29.31%, respectively,
when planted under the crown. Cotton under the crown was 6.58% shorter compared
to plants outside the crown. Average bud production and average fresh biomass
for cotton plants was 13.06% and 36.06% less, respectively, when planted under
the crown of shea trees.