Parasitism of plum tree (Dacryodes edulis, Burseraceae) by Loranthaceae in the locality of Fotetsa-Dschang (West-Cameroon)

Plum tree (Dacryodes edulis) in Cameroon is a fruiting and shading tree in agro ecosystems. It is of nutritional, medicinal and economical values to local population. Its productivity is reduced partially in some localities by the Loranthaceae parasites. These parasites were censured on plum trees in all the nine villages of the locality Fotetsa (West Region of Cameroon) where they are mainly shading plants in coffee farms. In each village, all fruits bearing plum trees located in a perimeter of 1850 × 60 m were observed and characterized using the stem diameter, number of Loranthaceae present and the taxon of the parasite. At Fotetsa, four Loranthaceae species attack plum trees: these are Tapinanthus apodanthus, Phragmanthera capitata, Tapinanthus oleifolius and Viscum congolense. The rate of parasitism varied significantly (from 41.46 to 62.74%) between the nine villages of the locality of Fotetsa in function of the different classes of plum tree stem circumference. Also, the number of Loranthaceae per plum tree varied in function of localities with maxima within 17 and 29 Loranthaceaae per tree. In each village, average mean number of Loranthaceaae per tree and average mean stem circumference were correlated. Considering the negative impact of Loranthaceae parasite on fruiting plant production, it is imperative to envisage preventive methods (limitation of species propagation) and curative methods (mechanical destruction of species fixed on the host plant) for fight against these hemiparasite phanerogames.