Use of essential oils from local plants as potential bio-herbicides to deplete Striga hermonthica seedbank

The parasitic weed Striga hermonthica (Del.) Benth, is a major biotic constraint to the production of cereal crops, particularly sorghum in Africa. The research was aimed to evaluate the allelopathic properties of local plants to inhibit Striga hermonthica weed from Burkina Faso. In this respect, the bio-herbicidal effect of essential oils from 10 local aromatic plants on the germination of S. hermonthica seeds, was evaluated. The research was conducted in 2017 at the phytopathology and weed science laboratory of INERA (Institut de l'Environnement et de Recherches Agricoles) located at Kamboinsé, Burkina Faso.The research using essential oils with 10% dilutions from 10 local aromatic plants were evaluated to inhibition of S. hermonthica germination. Dilutions of 0.2% and 0.4% were applied on conditioned Striga seeds to test their ability to induce Striga germination. Parameters were analyzed using the ANOVA, and the means were compared using DMRT at level of 5%. Germination data of Striga seeds were analyzed using the GenStat Release 12.1 software. The results showed that oils from Cymbopogon citratus (10%)inhibited completely the germination. The ones from Cymbopogon nardus L. and Lippia multiflora Moldenke also inhibited significantly the germination rate compared to the untreated control. Dilutions of 0.2% from four plants essential oils significantly stimulated germination by 5.26% to 60.64% (C. citratus). As we can observe from the above, the oil some essential oils contain metabolites that can be used as bio-herbicides to control S. hermonthica and improve cereal yield. Their use in field conditions can limit environmental pollution and contribute to fight against climate change.