Aqueous extracts from indigenous plant in Burkina Faso with bio-herbicide properties to reduce Striga hermonthica (Del.) Benth propagation

Abstract

Background: The genus Striga includes 11 parasitic plants species of food crops in at least 50 African countries. Striga hermonthica (Del.) Benth. is a major biotic constraint to the cereal crops production in Africa. It is the most widespread species in fields in Burkina Faso and grows on all types of soil inducing losses estimated at 35–40% on sorghum and millet. The substantial reductions in yield caused by S. hermonthica contribute significantly to an insufficient food supply for the populations in the area. Methods: This study aims to identify local plants with bio-herbicidal properties for the management of S. hermonthica. The inhibiting and stimulating effect of aqueous extracts from 13 local plant species on the germination of S. hermonthica seeds was assessed in vitro. Results: The aqueous extracts from the leaves of Azadirachta indica A. Juss, Jatropha curcas L., Jatropha gossypiifolia L., Lawsonia inermis L. and those from the leafy stems of Cassia obtusifolia L., Crotalaria retusa L., Phyllanthus amarus L. completely inhibited germination of Striga. Five other plant extracts significantly stimulated germination, of which the highest germination rate (60%) was recorded with the extract from Euphorbia hirta L. leafy stems. Conclusions: The plant extracts thus constitute an ecological avenue for S. hermonthica control. Further experiments could lead to the formulation of bio-herbicides against the parasitic plant to improve cereal production while limiting environmental pollution.