Use of Local Plant Aqueous Extracts as Potential Bio-herbicides against Striga hermonthica (Del.) Benth. in Burkina Faso

Abstract

This study was conducted to evaluate the allelopathic properties of endogenous plant species against Striga hermonthica (Del.) Benth., a root parasitic weed. In this respect, twenty five water extracts and eight freeze dried water extracts from sixteen plant species were screened in bio-assays to test their ability to induce or inhibit the germination of S. hermonthica seeds. Striga seeds were conditioned either in 10% water extracts or in 10% diluted lyophilisats to check their inhibition effect on Striga seed germination. Three doses, 1, 5 and 10% of water extracts were applied on conditioned Striga seeds to test their ability to induce Striga germination. Aqueous extracts from four plant species reduced Striga seed germination by 95.8 to 99.8% compared to the untreated control. Aqueous extracts from two others also significantly reduced Striga germination by 93.1 and 86.3%, respectively. Lyophilisats from four species inhibited Striga seeds germination, whereas that of two others reduced Striga seeds germination by 93.5 and 99.6%, respectively. Only 1% aqueous extracts of Ceiba pentandra and Eucalyptus camaldulensis significantly stimulated Striga seed germination by 39.2 and 38.9%. These results pointed out that the metabolites produced by some of the local plant species may have the potential to be used as bio-herbicides to control S. hermonthica and enhance cereals yield.