Influence of Pterocarpus erinaceus Poir. on the Growth and Yields of Groundnut (Arachis hypogea L.) in Agroforestry Parks in the Districts of Tenghory and Kataba 1 (Bignona Department, Lower Casamance)
In Lower Casamance, Pterocarpus erinaceus occupies a very important place in agroforestry parks. It is often grown in association with the most important cash crop of the area, groundnut (Arachis hypogea L.). Thus, the objective of this study is to contribute to a better understanding of the interactions between trees and groundnut cultivation in agroforestry parks in Lower Casamance. To this end, in each of the two districts (Tenghory and Kataba 1) three Pterocarpus erinaceus trees were selected in three separate communes. For each P. erinaceus tree selected and following each of the four cardinal directions, three situations were defined: at R/2, at 1.5 R and at 2 R from the trunk, with R the radius of the crown. Thus, 12 yield squares were installed around each selected tree, for a total of 72 yield squares installed in the two districts. The parameters measured were the height of the peanut plants, the number of pods produced per plant, and the yield in flakes and pods. The results show that geographical orientation significantly influenced plant height (p = 0.004) but not the number of pods/plant (p = 0.6). As for the distance to the trunk of Pterocarpus erinaceus, it induced a significant variation in the number of pods/plant (p = 0.009) but did not induce a significant effect on the other parameters. Yields varied between 1.56 Tons M S /ha and 2.02 Tons M S /ha for the hay, and between 1.03 Tons M S /ha and 1.45 Tons M S/ha for the pods. The results of this study constitute a useful source of information for a better management of the productivity of the agroforestry parks of the department of Bignona.