Parasitic plant species of food crops in Africa: biology and impact, study in Mali. 1. Identification and biology of parasitic plants. 2. Impact of parasitic plants based on the results of a study in Mali (1991-1994.
A study was carried out in 7 villages in southern Mali between 1991 and 1994, leading to the identification of Alectra vogelii, Striga gesnerioides, Buchnera hispida, Striga hermonthica, Striga aspera, Striga asiatica, Rhamphicarpa fistulosa, Striga passargei, Striga brachycalyx, Striga bilabiata ssp. rowlandii and Striga linearifolia. A survey of farmers highlighted the problems caused by parasitic plants and identified the species concerned and methods for their control. Six species frequently infest crops in the villages studied, and Striga hermonthica was present on all sites. Smallholders know the parasitic plants but they are unaware of how they reproduce and are generally unable to recognize the different species. Distributions of different species and degrees of infestation were mapped. The distributions can be explained by environmental conditions, previous land use, and the effect of runoff on dispersal. As a result of infestation, land is abandoned, sometimes leading to outmigration. Infestation patterns were examined as a function of the infestation density and various other factors relating to the farming system. Nearly half of the village farmland surveyed was infested, with 43% of the land potentially at risk. Infestations vary depending on the type of field, the crop grown (sorghum, millet, maize), and the cropping practices (intercropping or monocropping). From authors' summary. KEYWORDS: TROPAG | Alectra vogelii | Striga asiatica | Striga aspera | Striga gesnerioides | Striga hermonthica | Rhamphicarpa fistulosa | weeds | parasitic plants | Striga | pest surveys | weed control | farm surveys | cereal crops | MALI | Mali-Sud.