Integrated Management of <i>Striga hermonthica</i> in Sorghum Using <i>Glomus mosseae</i> , <i>Bacillus megaterium</i> , and Phosphorus

The root parasitic weed <i>Striga hermonthica</i>, a member of the Orobanchaceae family, is a major constraint to cereal production in sub-Saharan Africa. Its germination is triggered by host-derived stimulants, which are upregulated under phosphorus (P) and nitrogen deficiencies. This study evaluated the effects of the arbuscular mycorrhizal fungus <i>Glomus mosseae</i>, the phosphorus-solubilizing bacterium <i>Bacillus megaterium</i> var. phosphaticum (BMP), and inorganic phosphorus (P₂O₅), applied individually and in combination, on <i>S. hermonthica</i> incidence and sorghum (<i>Sorghum bicolor</i>) growth. Uncontrolled <i>S. hermonthica</i> parasitism reduced sorghum height by 48%-54% and shoot biomass by 71%. <i>G. mosseae</i> alone reduced <i>S. hermonthica</i> emergence and biomass by 87%-100% and 93%, respectively, while increasing sorghum height by 89%-115% and shoot biomass by 351%. The combination of <i>G. mosseae</i> with BMP increased sorghum height by 116%-139% and shoot biomass by 314%. BMP alone reduced <i>S. hermonthica</i> emergence and biomass by 57%-65% and 68%, respectively, and phosphorus alone reduced <i>S. hermonthica</i> emergence and biomass by 29%-42% and 51%, respectively. The combinations of <i>G. mosseae</i> with BMP, <i>G. mosseae</i> with phosphorus, and <i>G. mosseae</i> with BMP and phosphorus achieved reductions in <i>S. hermonthica</i> emergence of 93%-100%, 82%-100%, and 87%-100%, and reductions in biomass of 93%, 87%, and 65%, respectively. Phosphorus suppressed arbuscular mycorrhizal fungus colonization, while BMP had no significant effect. These findings highlight the potential of <i>G. mosseae</i> and <i>Bacillus megaterium</i>, individually and in combination, as biocontrol agents for reducing <i>S. hermonthica</i> and improving sorghum growth in low-fertility soils.